Defending the Northwest Forest Plan Oregon Wild store All Events Also a part of this series:Hardesty Mountain Roadless Area: Vigilance, Close Calls, & HeroesLookout Mountain: Roadless Beacon of the OchocosBeloved Metolius RiverEvery Wild Place Has a Story Puckery sweet huckleberries lined the upper Badger Creek trail within easy reach Ancient western red cedars flared branches like bird wings and silver firs rose columnar and elegant among Engelmann spruce A Pacific wren dueted with a silvery stream protects many centuries-old trees and ecosystems of breathtaking diversity I would learn of one lucky break that likely made a key difference in Badger Creek’s inclusion in the Oregon Wilderness Bill of 1984 That story of a fateful aerial flight came from Dave Corkran Hood Forest Study Group (no longer active) and lives in Portland with his wife Char A beloved history teacher at Portland’s private Catlin Gabel High School for 35 years his environmental passion remains strong at age 89 My phone call with Dave skimmed the surface of his lifetime engaged with the wilds—from surveying potential wilderness areas in Wyoming and Montana after passage of the 1964 Wilderness Act to fighting to save the Bull Run watershed (Portland’s drinking water) from logging “Have you been to the top of Lookout Mountain?” he asked evoking that spectacular 360-degree view of Mt and Three-Fingered Jack from the 6525-foot-high summit “Ruth and Ken Love were the most interested in our group in saving Badger Creek,” he said The couple coauthored a Guide to Trails of Badger Creek 92 pages of detailed hikes and a list of birds The Portland couple founded a member group of Oregon Wilderness Coalition (OWC) The Badger Creek Association consisted of themselves—Ruth and Ken OWC encouraged people passionate about specific wild areas to form a group and grow the coalition There’s power in naming wild places under threat The story Dave would tell me about Ken’s flight over the proposed Badger Creek Wilderness with Representative Les AuCoin is one I’m betting few people have heard If Ken were alive today (he passed in 2021) I think he’d be pleased more people know of this fortunate day The flight was part of a successful effort by the Mt Hood Forest Study Group to get the attention of politicians reluctant to clash with the timber industry “We finally persuaded Senator Mark Hatfield and Congressman Les AuCoin to look at all proposed wilderness areas around Mt Hood,” Dave said Representative AuCoin strained to hear Ken’s words above the noise of the propellers Perhaps he was extolling the wild forests fed by three main creeks—Badger But the savvy legislator registered something else He saw where the plane was heading—east to a treeless landscape somewhere toward Dufur “So instead of looking at the timber below him he saw all that country without trees and figured this place wouldn’t impinge on logging,” Dave said I heard him chuckling and could picture him shaking his head in amusement He knew Ken hadn’t meant to give the congressman that impression The final version of the 1984 bill included old growth forests in the Mt Hood area in Badger Creek Wilderness as well as Salmon-Huckleberry Wilderness (44,600 acres) Oregon Wild and its long list of coalition members achieved a significant victory statewide—adding 21 new Wilderness areas and expanding eight existing ones Every one of those areas has a story of people championing the places they loved The 1984 Act added more than 860,000 acres to the Wilderness preservation system in Oregon the state total is almost 2.2 million acres.—with 350,000 acres added since 1984 Before my conversation with Dave Corkran ended I couldn’t resist asking him if he’d known Brock Evans the legendary eco-warrior hired by Dave Brower in 1967 as the Sierra Club’s Pacific Northwest field representative— and still active as a board member of Greater Hells Canyon Council from his home in La Grande Start agitating for the area to be set aside Wild areas are far more than lines on the map They are headwaters of drinking watersheds strongholds for great forests capturing and storing massive amounts of carbon Draw a line….Trace the wilderness boundaries on a map with your finger Celebrate Wilderness—the green protected places free from roads Draw the lines around Oregon’s more than five million acres of roadless wilds on national forests In this year of decade anniversaries—60 for the Wilderness Act and 40 for the Oregon Wilderness Act—there’s no better time than now to pull out the maps and dream big To keep up our spirits and remember why it’s all worth it I believe in revitalizing our spirits often I am back on the Badger Creek trail picking huckleberries until my fingers stain purple I kneel to notice the low-down way of vanilla leaf and twinflower Run my fingers over ferns like feathers and into icy spring water trickling by a tipped-up tree root of a great fallen fir  Spread my arms wide around the buttressed trunk of a western redcedar and pines before I zip open my tent beside Gumjuwac Creek flowing under great downed trees to a confluence with Badger Creek I give gratitude to all that shapes wild forests and is so often misunderstood—fungi and trees packed tight together in their way of companionship Honor the legacy of those who came before us Take a Hike: Badger Creek Trail Oregon’s Ancient Forests, a Hiking Guide, by Chandra LeGue, Oregon Wild—for several hikes in the Mt. Hood area outside of protected Wilderness, including Fifteen Mile Creek—just north of Badger Creek Wilderness. (Buy it here!) Gumjuwac: The name originates from an early sheepherder called Gum Shoe Jack known for tromping around in his rubber boots—or gum boots Hood National Forest lands have been the home of many peoples Gumjuwac-Tolo Research Natural Area: Designated in 1996, the 3600 acres within the Badger Creek Wilderness Area encompass a high diversity of forest and stream ecosystems. Natural areas are tracts of wildlands that serve as prime examples of distinct natural features and ecosystems Badger Creek Trail to Lake – Chandra and Marina’s Tree Species list including a few that might be considered shrubs but grew to tree size so we included them (elderberry) While we noticed orderly shifts of species by elevation (like mountain hemlocks we were struck by surprising companionships n this east-west transition zone Oregon’s wolves appear to be bouncing back within the numbers there are some concerning trends The Bureau of Land Management failed to consider harm to ecosystems and failed to follow required environmental review processes Staying informed is the first step to becoming a public lands and native wildlife advocate ©2024 Oregon Wild | Privacy Policy Volume 2 - 2019 | https://doi.org/10.3389/ffgc.2019.00079 This article is part of the Research TopicForest Management Alters Forest Water Use and Drought VulnerabilityView all 13 articles To mitigate negative impacts of drought stress in the face of climate change mixtures of tree species such as those between European beech (Fagus sylvatica) and silver fir (Abies alba) are assumed to lower risks in forest management This study investigates the influence of mixing beech and fir on tree growth in general and in particular on tree species responses to the extreme drought event of 2003 we analyzed basal area increment series and carbon isotope composition (δ13C) in wood of ~160 trees from three mixed-species sites in Germany and one site in Croatia Overall growth performance for both fir and beech increased with proportions of the admixed species when accounting for the interactions with tree size and competition intensity Mixing improved growth of large trees for both species irrespective of neighborhood density whereas smaller trees benefitted only in denser neighborhoods Positive mixing effects on radial growth were more pronounced in fir compared to beech yet the latter benefitted by admixture of fir with regard to growth recovery following drought Both the resistance of radial growth against reduction during drought as well as the variation of isotopic composition throughout the drought period were not affected by mixing indicating that water-use in these two species was not complementary under drought stress Although trees from both species exhibited growth reductions during the drought fir maintained higher absolute growth levels than beech during the drought Both species benefited from growing in mixed neighborhoods but complementary effects depended on tree size and neighborhood density Mixing fir and beech leads to positive or neutral effects on growth performance of trees also in response to an extreme drought event Since increasing tree species richness also spreads the risks associated with extreme events mixtures of beech and fir can be recommended as a possible alternative for more drought-sensitive stands such as spruce monocultures Neither of these studies analyzed the growth response of beech to drought when it was mixed with fir and it remains unclear if benefits for fir came at the expense of beech or if both species benefitted from mixing with regard to their drought response no study has investigated the effect of mixing on drought sensitivity in terms of both radial growth and isotopic composition for fir and beech if mixing these two species improves the drought tolerance of both species we analyzed basal area increment (BAI) of 160 trees from three sites in south-western Germany and from one site in Croatia with a particular focus on periods of extreme drought stress For beech and fir trees growing in neighborhoods of different admixture proportions we tested whether mixing influenced the resistance and resilience of growth to severe soil drought conditions we compared the carbon isotope composition (δ13C) among years with different climatic conditions for trees in mixed vs We hypothesized that for both silver fir and European beech: (1) Benefits of mixing on overall growth are similar for the two species and show similar patterns over time (2) Mixing leads to a positive effect on the overall growth performance of both species but benefits vary with tree size and neighborhood competition (3) Drought tolerance of trees is higher in mixed compared to monospecific neighborhoods Data were collected at four sites, three in the Black Forest in South-western Germany and one that was close to the city of Gospic in Croatia in the Velebit mountains (Table 1). Climate among sites in the Black Forest varies with altitude (ranging from 400 to 860 m.a.s.l.) corresponding to a decrease in mean temperature from 9.8 to 8.6°C and an increase of annual precipitation from 1,130 to 1,370 mm (Table 1) The Croatian site has similar annual precipitation as the highest-elevation site in the Black Forest Soils at all sites are Cambisols which developed on limestone in Croatia and on paragneiss or sandstone at the German sites Forest stands were selected for sampling based on the following criteria: (1) Mixed stands dominated by fir and beech with each species having at least 30% of total stand basal area; percentage of other species below 15% basal area (2) Heterogeneous mixing within the stand; including sections with monospecific patches of each species as well as parts with fine-grained tree-wise mixtures (3) More or less even-aged and early mature stands (4) Maximum of one thinning intervention in the last 5 years and stumps had to be datable to permit identification of the timing of interventions during the last decade Site and stand description for the three study sites in Germany and the fourth site in Croatia approximately twenty trees per species were selected evenly across three groups of neighborhood composition reflecting differing mixture proportions of fir and beech comprising trees with mostly conspecific neighbors trees being surrounded by an even mix of the two species and trees surrounded by heterospecific neighbors Additional selection criteria for sample trees were that they had to (1) be of at least co-dominant status; (2) show no visible signs of injuries or loss in vitality; (3) have not more than one tree of a third species in their neighborhood; (4) have neighborhoods of comparable density (+/– closed conditions) and (5) not be part of the neighborhood of the next sample tree to avoid spatial correlation The minimum distance between the selected trees within each stand varied among stands depending on their age and size diameter at breast height (DBH) and extracted at that height two cores with an increment borer from perpendicular directions starting upslope and going in clockwise direction Assuming that spatial extent of above ground competition also reflects below ground competition trees were considered to be actual neighbors if their crown interfered with the crown of the central trees we determined species identity and DBH and measured the distance to the central tree to determine neighborhood density and composition The well-documented Pan-European drought event of 2003, also obvious in precipitation and temperature data at the study sites (Figure 1) was selected for analyzing the effect of mixing on the drought response of growth Climate diagrams for two weather stations in Gospic in Croatia (top) and Conventwald in Germany (bottom) depicting mean temperature (red) and sum of precipitation (blue) of the vegetation period (May to September) from 2000 to 2014 (15) δ13C values were calculated using the following equation where 13Rsample is the 13C/12C ratio of the sample, and 13Rstandard denotes the 13C/12C ratio of the standard. Values are expressed in per mil (%0) by multiplying the δ value with the factor 1000 (Coplen, 2011; Brand et al., 2012) The δ13C values are given on the δ13CIAEA-603–LSVEC scale by analyzing the samples against a calibrated in-house-standard (Acetanilide: −30.06 ± 0.05%0) A quality control standard (Caffeine: −40.46 %0) was interspersed between samples The daily precision of the sequences was equal to or better than 0.1%0 (1) Temporal analyses to test for the overall effect of mixing on growth complementarity of the two species over time (H1) (2) Neighborhood analyses to determine the effect of mixing and other growth-relevant parameters on tree growth for a period for which exact data on neighborhood competition and composition were available (H2) (3) Drought response analyses to test the influence of mixing on drought tolerance of trees (H3) Summary statistics (means and standard deviation SD in brackets) for response variables and (continuous) predictors used in the three models related neighborhood analysis (testing H2) and drought response analysis (testing H3) To examine if growth of the two tree species was positively affected by mixing and if mixing effects persisted over time, we calculated the response variable complementarity of annual growth (BAI) of the period 2000–2016 as a modification of the mixing response suggested by Vitali et al. (2018) and Forrester et al. (2013) as: temporal trends of BAI series were tested separately for each site and species using linear regression The log transformation was applied on the response variable meanBAI3 to obtain normal residuals After determining the optimal random structure “*” denotes that main effect and interactions of the respective variables are considered in the model and the “1|x” notation denotes a random intercept with grouping variable x (a) Admixed_prop: Admixture proportions (%) based on Hegyi-index (b) Hegyi: a modified version of the competition index according to Hegyi (Lee and Gadow, 1997) (c) BAL: Basal area of trees larger than the focal tree in m2 (d) Martonne: an aridity-index (Martonne, 1926) The effect of mixing on drought tolerance of beech and fir trees was analyzed using the following response variables regarding the growth and isotopic variation throughout the drought period. For tree growth, we calculated three drought response variables by dividing the observed growth into resistance of radial growth to drought (RES), its recovery from drought (REC), and the resilience to drought (RESIL) as suggested by Lloret et al. (2011) as a log transformation was applied on all indices (except for RESILBAI calculated with 2 year periods which could be directly used without any transformation) For analyses of carbon isotopic composition (δ13C) in tree-rings, we selected the same years (2002–2004) that were used to calculate growth responses to drought. Analogous to calculations of growth resistance and following the analysis done by Schaefer et al. (2017) the drought resistance of δ13C (RES13C) was quantified as the ratio between the value of the dry year and the wet pre-DY (Equation 4a) so that a higher value of RES13C reflects a smaller increase in δ13C in the dry year indicating a lower stomatal response and thus a lower level of drought stress the recovery and resilience of δ13C following drought was calculated as the ratio between the post-DY 2004 and the DY 2003 (REC13C Equation 4b) and between the post-DY 2004 and the pre-DY 2002 (RESIL13C The ratios RES13C and RESIL13C could be directly used as response variables in our models while REC13C had to be log-transformed to obtain a normal distribution To visualize the overall mixing effect on growth and isotopic response to drought, the complementarity of drought responses was calculated using the same framework as used for BAI (Equation 1) according to Vitali et al. (2018) as: where RespMix is the average value of each of the drought response indices (resistance and resilience of BAI and 13C) of each tree in mixed neighborhoods and RespMono is the average value of either response of all trees in mono-specific neighborhoods from the same species and site Means of annual basal area increments (BAI) of trees from two species (fir: blue and beech: gray) at four sites (Conventwald Trend-lines and bands represent smoothed conditional means using linear model (geom_smooth function Stars indicate a significant trend (p < 0.05) over time which was detected based on linear regression of BAI vs For beech, decreasing BAI trends over time are visible at two sites (Hexental and Croatia), while fir shows decreasing growth only at the Hexental site (Figure 2). Both species exhibited positive BAI trends at the Freiamt site but this is most likely an age-related effect as trees at this site were considerably younger than at the other sites (Table 1) Annual means and SE (thin bars) of complementarity (%) of basal area increments (BAI) of beech (gray) and fir (blue) for years 2000–2016 Complementarity of BAI reflects the average growth (BAI) of trees experiencing interspecific interactions compared to that of trees which are subjected to intraspecific interactions (see Equation 2 for calculation) Parameter estimates with standard errors (S.E.) of linear mixed model fit for temporal analyses by REML t-tests using Satterthwaite approximations to degrees of freedom for complementarity of BAI Annual means and SE (thin bars) of complementarity (%) of basal area increments (BAI) of beech (gray) and fir (blue) for years 2000–2016 for the 4 sites (Conventwald Bands represent loess-smoothed conditional means (geom_smooth function with ‘loess' and formula “y ~ x” with span = 1 Complementarity of BAI reflects the average growth (BAI) of trees experiencing interspecific interactions compared to that of trees which are subjected to intraspecific interactions (see Equation 2 for calculation) Average tree growth from 2014 to 2016 (meanBAI3) increased significantly with admixture proportions for fir at two sites while no relationship between meanBAI3 and admixture proportions was found for beech at any site (Figure 5). However, results of the most parsimonious mixed model indicate that in the presence of several confounding factors, meanBAI3 was positively related to admixture proportions in both species (p < 0.05) (Table 4) This highlights the need to take into account additional growth-relevant factors Results of the mixed model indicated a direct positive effect of DBH on meanBAI3 (p < 0.001) and a direct negative effect of the competition index on meanBAI3 (p < 0.01) model outcomes showed two significant positive interactions of the relationship between admixture proportion and meanBAI3 with DBH and the Hegyi-index (both p < 0.001) The selection of the random effect structure (using REML) led to site as the most important random effect The random effect variances showed a moderate variability of the signal among sites Since meanBAI3 values assumed after transformation approximately a range of 3.6 the standard deviation of 0.40 represents 11% of the range of the response (likewise the standard deviation of 0.40 for the residual error represents 11% of the response range) Relationship of (transformed) response variable meanBAI3 (average BAI of last 3 years) with admixture proportions for beech (gray) and fir (blue) trees at 4 sites (Conventwald Pearson-r and p-values refer to results of linear regression for each species and site separately Parameter estimates with standard errors (S.E.) of the best linear mixed model fit for neighborhood analyses by REML t-tests using Satterthwaite approximations to degrees of freedom both species were combined for these predictions Figure 6. Comparison of model predictions (see Table 4) for the relationship between the (back-transformed) response meanBAI3 (y-axis) (average BAI from 2014 to 2016) with increasing admixture proportions (x-axis) in % for (A) trees of different dimensions in terms of DBH and (B) for 3 levels of neighborhood competition Hegyi = 0.5 (blue) The selection of random effect structure (using REML) pointed to site as the most important random effect and the random effect variances showed a low variability of the signal among sites (The standard deviation for site represents merely <7% of the range of the responses and the standard deviation for residual error represents <18% of the response range) Parameter estimates with standard errors (S.E.) of linear mixed model fit for drought analyses by REML t-tests using Satterthwaite approximations to degrees of freedom for the response variables reflecting growth and isotopic response to 2003 drought: resistance (RES) and resilience (RESIL) of BAI and δ13C Complementarity effects of mixing on growth responses to the 2003-drought of European beech (gray) and silver fir (blue) in terms of resistance during drought (RES) and resilience to drought (RESIL) using (A) one and (B) two year(s) in the pre- and post-drought period Stars (***P < 0.001 and ****P < 0.0001) indicate significant differences between the 2 species for each index and “ns” indicates no significant difference between the 2 species (P > 0.05) based on t-tests Note that T-test was done for with transformed (∧0.25) data while figure depicts raw data Comparison of means (SE depicted as thin bars) of carbon isotopic composition δ13C in wood of the years 2002 and 2004 between trees growing in monospecific (gray) and mixed (red) neighborhoods for beech (left) and fir (right) ns indicates that there is no significant difference between mixed and monospecific neighborhoods within species based on t-test Complementarity effects of mixing on isotopic response to the 2003-drought of European beech (gray) and silver fir (blue) in terms of resistance during drought (RES) recovery following drought (REC) and resilience to drought (RESIL) “ns” Indicates no significant difference (P > 0.05) between the 2 species for each index based on t-tests Results of this study highlight the importance of incorporating data on actual neighborhood composition and competition when examining the effects of mixing on growth performance of individual species Positive effects of mixing on overall growth performance were more pronounced in fir than in beech yet the latter benefitted more from admixture of fir with regard to the growth recovery following drought both the growth resistance during drought as well as the variation in isotopic composition throughout the drought period were not affected by mixing In the following we will first discuss our results in the same order as our hypotheses; regarding (1) effects of mixing on the overall and temporal growth performance of trees (2) the interactive effect of mixing with other growth-relevant factors on overall growth performance and (3) how mixing affected the drought response of trees Whether or not mixing may improve water or nutrient availability of the two species cannot be ascertained on the basis of this study Our findings with regard temporal trends of complementarity and growth should be interpreted with caution as we analyzed only the most recent 16 years our study shows that such broad trends may not occur at every site and that variability among sites in magnitude and direction is very high recovery and resilience in fir compared to beech they analyzed several drought events and sites across a larger climatic gradient Viewed from another perspective, the finding of comparable growth and resistance of isotopic composition indicates that the overall faster growth of trees in mixed compared to monospecific neighborhoods was not a disadvantage for either of the species during drought (Forrester, 2014) as has been reported for other species combinations (Metz et al., 2016) The complementarity of growth recovery was significantly higher in beech than in fir. This finding of greater mixing benefits for beech than for companion species is in agreement with other studies (Mölder and Leuschner, 2014; Metz et al., 2016). In contrast to our finding, fir trees growing in more functionally diverse stands recovered more quickly (Gazol et al., 2016) The positive effects of fir trees on growth recovery of beech imply lower competitive stress once water became less limiting in the post-drought year. We can only speculate about the actual mechanisms behind the competitive reduction in beech in the year following the drought event. One possible explanation could be that beech fine-root systems with lower construction costs can recover more quickly from the drought (Meier and Leuschner, 2008) Neither the resilience of growth and of δ13C was affected by species or mixing which is most likely due to persisting water shortages in 2004 which is also indicated by δ13C values and growth not returning to pre-drought levels at the majority of sites Both species benefited from growing in mixed neighborhoods but complementarity effects were dependent on tree size and neighborhood density Results of this study demonstrate that mixing silver fir and European beech leads to positive or neutral effects on growth performance of trees also in relation to an extreme drought event Our results demonstrate that mixing fir and beech offers no advantages for mitigating growth responses during periods of extreme water shortage mixing fir and beech can help to improve the growth recovery following drought in beech but not in fir faster growth rates of trees of both species in mixed compared to monospecific neighborhoods have no disadvantages for their response to drought mixtures of beech and fir may be considered at appropriate sites as an alternative for more drought-sensitive Norway spruce forests The datasets generated for this study are available at: https://freidok.uni-freiburg.de JB conceived the study and acquired funding for the project JB and JS designed the study and discussed and interpreted the results and contributed to the writing of the final manuscript Financial support by the Federal Minister of Agriculture (BML) and the Federal Minister of Environment (BMU) via the Federal Institute of Agriculture and Nutrition (BLE) in the frame of the project Buchen-Tannen-Mischwälder zur Anpassung von Wirtschaftswäldern an Extremereignisse des Klimawandels (BuTaKli) within the program Waldklimafondsis gratefully acknowledged (Grant No The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest We gratefully acknowledge the help of district forester Johannes Wiesler from the community Hexental in Breisgau-Hochschwarzwald for his personal support and the provision of an additional sampling site The authors thank the forestry districts Breisgau-Hochschwarzwald and Emmendingen in Germany and Mladen Ivankovic from the Croatian Forest Research Institute Gopsic for supporting this study by providing data on tree composition of the forest stands and Bárbara Magdalena San Martín for their assistance in fieldwork We express our gratitude to Sven Hofmann and Nanja Unger for the many hours spend in the lab during sample preparation and processing of growth data The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/ffgc.2019.00079/full#supplementary-material Seasonal variation in delta13C and delta18O of cellulose from growth rings of Pinus radiata CrossRef Full Text | Google Scholar Biodiversity promotes tree growth during succession in subtropical forest Tree rings indicate different drought resistance of a native (Abies alba Mill.) and a nonnative (Picea abies (L.) Karst.) species co-occurring at a dry site in Southern Italy “Ecological stability of mixed-species forests,” in Mixed-Species Forests CrossRef Full Text | Google Scholar How do mixing tree species and stand density affect seasonal radial growth during drought events Larger trees suffer most during drought in forests worldwide Adaptive forest management in central Europe: climate change impacts Contrasting effects of environmental change on the radial growth of co-occurring beech and fir trees across Europe and European beech modify competitive interactions in central European mature mixed forests Improved precision of coupled delta13C and delta15N measurements from single samples using an elemental analyzer/isotope ratio mass spectrometer combination with a post-column six-port valve and selective CO2 trapping; improved halide robustness of the combustion reactor using CeO2 Condés Climate modifies tree interactions in terms of basal area growth and mortality in monospecific and mixed Fagus sylvatica and Pinus sylvestris forests Condés Mixing effect on volume growth of Fagus sylvatica and Pinus sylvestris is modulated by stand density CrossRef Full Text | Google Scholar Guidelines and recommended terms for expression of stable-isotope-ratio and gas-ratio measurement results Structural diversity promotes productivity of mixed uneven-aged forests in southwestern Germany Dănescu Stability of tree increment in relation to episodic drought in uneven-structured Temporal variation of competition and facilitation in mixed species forests in Central Europe Morphological plasticity of European beech (Fagus sylvatica L.) in pure and mixed-species stands CrossRef Full Text | Google Scholar Growth variations of Common beech (Fagus sylvatica L.) under different climatic and environmental conditions in Europe—a dendroecological study Google Scholar Carbon isotope discrimination and photosynthesis CrossRef Full Text | Google Scholar The spatial and temporal dynamics of species interactions in mixed-species forests CrossRef Full Text | Google Scholar Transpiration and water-use efficiency in mixed-species forests versus monocultures: effects of tree size Predicting the spatial and temporal dynamics of species interactions in Fagus sylvatica and Pinus sylvestris forests across Europe A review of processes behind diversity—productivity relationships in forests CrossRef Full Text | Google Scholar Drought responses by individual tree species are not often correlated with tree species diversity in European forests Complementarity in mixed-species stands of Abies alba and Picea abies varies with climate Google Scholar Functional diversity enhances silver fir growth resilience to an extreme drought CrossRef Full Text | Google Scholar Post-drought resilience after forest die-off: shifts in regeneration Potential risks for European beech (Fagus sylvatica L.) in a changing climate Grissino-Mayer Evaluating crossdating accuracy: a manual and tutorial for the computer program COFECHA Google Scholar Having the right neighbors: how tree species diversity modulates drought impacts on forests Does drought influence the relationship between biodiversity and ecosystem functioning in boreal forests Tree diversity does not always improve resistance of forest ecosystems to drought Climate change may cause severe loss in the economic value of European forest land Mixing effects in Norway Spruce—European beech stands are modulated by site quality Northern forest tree populations are physiologically maladapted to drought leaf phenology and photosynthetic activity in promoting complementary use of light among coexisting species in temperate forests CrossRef Full Text | Google Scholar Tree diversity drives forest stand resistance to natural disturbances Competition for light and water play contrasting roles in driving diversity-productivity relationships in Iberian forests Rapid climate change-related growth decline at the southern range edge of Fagus sylvatica CrossRef Full Text | Google Scholar lmerTest package: tests in linear mixed effects models CrossRef Full Text | Google Scholar Environmental controls over carbon dioxide and water vapor exchange of terrestrial vegetation Mixed stands reduce Abies alba tree-ring sensitivity to summer drought in the Vosges mountains Sensitivity of French temperate coniferous forests to climate variability and extreme events (Abies alba Iterative bestimmung der konkurrenzbäume in Pinus densiflora beständen Google Scholar Components of tree resilience: effects of successive low-growth episodes in old ponderosa pine forests CrossRef Full Text | Google Scholar Silver-fir (Abies alba MILL.) neighbors improve water relations of European beech (Fagus sylvatica L.) L'indice d'aridité CrossRef Full Text | Google Scholar Darcy's law predicts widespread forest mortality under climate warming CrossRef Full Text | Google Scholar “Relationships between tree height and carbon isotope discrimination,” in Size- and Age-Related Changes in Tree Structure and Function Belowground drought response of European beech: fine root biomass and carbon partitioning in 14 mature stands across a precipitation gradient CrossRef Full Text | Google Scholar Site-adapted admixed tree species reduce drought susceptibility of mature European beech The symmetry of competitive interactions in mixed Norway spruce Multiple factors modulate tree growth complementarity in Central European mixed forests Mölder European beech grows better and is less drought sensitive in mixed than in pure stands Tree neighbourhood effects on radial increment CrossRef Full Text | Google Scholar A basal area increment model for individual trees growing in even- and uneven-aged forest stands in Austria CrossRef Full Text | Google Scholar II and III to the fifth assessment report of the Intergovernmental Panel on Climate Change IPCC Google Scholar The effect of biodiversity on tree productivity: from temperate to boreal forests CrossRef Full Text | Google Scholar Pinheiro, J., Bates, D., DebRoy, S., Sarkar, D, and R Core Team. (2019). nlme: Linear and Nonlinear Mixed Effects Models. Available online at: https://CRAN.R-project.org/package=nlme (accessed September 27 Google Scholar Drought-driven growth reduction in old beech (Fagus sylvatica L.) forests of the central Apennines A re-evaluation of Reineke's rule and stand density index CrossRef Full Text | Google Scholar Tree species mixing can increase maximum stand density CrossRef Full Text | Google Scholar Forest stand growth dynamics in Central Europe have accelerated since 1870 Comparison between the productivity of pure and mixed stands of Norway spruce and European beech along an ecological gradient Effect of tree species mixing on the size structure CrossRef Full Text | Google Scholar Resistance of European tree species to drought stress in mixed versus pure forests: evidence of stress release by inter-specific facilitation R Core Team (2014). R: A Language and Environment for Statistical Computing. Vienna, Austria. Available online at: http://www.R-project.org/ (accessed September 27 PubMed Abstract | Google Scholar Past and future evolution of Abies alba forests in Europe - comparison of a dynamic vegetation model with palaeo data and observations Stable carbon isotopes in tree rings of beech: climatic versus site-related influences CrossRef Full Text | Google Scholar Drought stress reaction of growth and Δ13C in tree rings of European beech and Norway spruce in monospecific versus mixed stands along a precipitation gradient Isotope signals as climate proxies: the role of transfer functions in the study of terrestrial archives CrossRef Full Text | Google Scholar Mitigation of drought by thinning: short-term and long-term effects on growth and physiological performance of Norway spruce (Picea abies) Heavy and frequent thinning promotes drought adaptation in Pinus sylvestris forests A recent growth increase of European beech (Fagus sylvatica L.) at its Mediterranean distribution limit contradicts drought stress The past ecology of Abies alba provides new perspectives on future responses of silver fir forests to global warming Overyielding in mixed forests decreases with site productivity CrossRef Full Text | Google Scholar Silver fir stand productivity is enhanced when mixed with Norway spruce: evidence based on large-scale inventory data and a generic modelling approach van der Maaten-Theunissen Drought sensitivity of Norway spruce is higher than that of silver fir along an altitudinal gradient in southwestern Germany Disentangling biodiversity and climatic determinants of wood production Model-based assessment of ecological adaptations of three forest tree species growing in Italy and impact on carbon and water balance at national scale under current and future climate scenarios Silver fir and Douglas fir are more tolerant to extreme droughts than Norway spruce in south-western Germany Know your neighbours: drought response of norway spruce silver fir and douglas fir in mixed forests depends on species identity and diversity of tree neighbourhoods Referencing strategies and techniques in stable isotope ratio analysis ConFlo III - an interface for high precision δ13C and δ15N analysis with an extended dynamic range doi: 10.1002/(SICI)1097-0231(19990715)13:13<1237::AID-RCM633>3.0.CO;2-C Patterns of drought tolerance in major European temperate forest trees: climatic drivers and levels of variability Zur Baumarteneignung bei Klimawandel: ableitung der Trockenstress-Anfälligkeit wichtiger Waldbaumarten aus Jahrringbreiten Google Scholar Mixed Effects Models and Extensions in Ecology With R CrossRef Full Text | Google Scholar Citation: Schwarz JA and Bauhus J (2019) Benefits of Mixtures on Growth Performance of Silver Fir (Abies alba) and European Beech (Fagus sylvatica) Increase With Tree Size Without Reducing Drought Tolerance Received: 16 September 2019; Accepted: 11 November 2019; Published: 26 November 2019 Copyright © 2019 Schwarz and Bauhus. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) distribution or reproduction in other forums is permitted provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited in accordance with accepted academic practice distribution or reproduction is permitted which does not comply with these terms *Correspondence: Julia A. Schwarz, anVsaWEuc2Nod2FyekB3YWxkYmF1LnVuaS1mcmVpYnVyZy5kZQ== Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher 94% of researchers rate our articles as excellent or goodLearn more about the work of our research integrity team to safeguard the quality of each article we publish and website in this browser for the next time I comment Δdocument.getElementById( "ak_js_1" ).setAttribute( "value" Website Design by Blaser Consulting Volume 6 - 2023 | https://doi.org/10.3389/ffgc.2023.1252462 This article is part of the Research TopicOld-Growth Forests of Southeast Europe and their Relevance for Forest ManagementView all 5 articles Species-rich mixed silver fir (Abies alba Mill.) forests dominated in the northern Apennines anthropogenic land use provoked a sharp silver fir decline approximately 5000 years bp The conservation of the silver fir in this region was mainly due to the establishment of monastic orders that preserved and even planted silver fir for its spiritual and economic value the best silver fir stands were included in the Parco Nazionale delle Foreste Casentinesi (FCNP) and have been submitted to low-intensive management or strict protection regardless of past land use and cultural history we have (1) analyzed the current structure of three silver fir forests that have had different ownership histories and (2) compared the structure of the three Italian forests among them and with two old-growth forests from the Dinaric Alps as a reference of naturalness The results show that the current structures of the three Italian forests are very different among them and are strictly related to past land use and Even if the Italian forests have experienced decades of low-intensity management or strict protection they are currently structurally very different from Dinaric old-growth forests Developing an old-growth structure in these forests can be very slow and The results also highlight the importance of recognizing protected areas as cultural landscapes that host an important biocultural diversity The current risk is that by applying almost exclusive biodiversity-centered management and setting difficult or impossible-to-achieve biodiversity goals the greatest richness of most European parks The Apennines are characterized by high forest cover and high regional tree species diversity and provide essential ecosystem services to millions of people. However, past anthropogenic land use has profoundly affected forests of the Apennine region (Vacchiano et al., 2017) and outweighed by far the effects of macroecological constraints in the Holocene (Henne et al., 2012; Brown et al., 2013) Intensive forest utilization occurred from medieval times until the first half of the 20th century. In the last decades, socioeconomic changes caused the abandonment of traditional farming or grazing activities in mountain settlements and the re-establishment and increment of forest cover (Frascaroli, 2013; Marini Govigli et al., 2021; Agnoletti et al., 2022) most of the pure or mixed silver fir forests in the northern Apennines have been included in the Parco Nazionale delle Foreste Casentinesi (FCNP) thereby creating both positive synergies and new challenges for the conservation of their naturalistic value and the historical most pure and mixed silver fir stands have been submitted to low-intensive management or strict protection regardless of past land use and cultural history more than 8,000 ha are covered by monospecific and monolayered silver fir forests and more than 23,000 ha of forests are covered by mixed forests with conifers and broadleaves This study is focused on three sites, the forests of Camaldoli, La Verna, and Sasso Fratino, which have had different land-use and land-ownership histories. We selected two forests of the Dinaric Alps, the forests of Perućica (BiH) and Biogradska Gora (MNE), as old-growth reference forests belonging to the same forest type (Sabatini et al., 2018) The specific objectives of this study are as follows: - to analyze the role of monastic rules and the spiritual attitude of religious orders in shaping the forest structure and composition of the current silver fir forests of the northern Italian Apennines - to compare the current structure of these forests against old-growth forests of the Dinaric Alps - to discuss the current forest dynamics and the effectiveness of present management policies on conserving the cultural heritage and restoring biodiversity We conducted this study in three forests of the FCNP established in 1993, containing some of the best remnants of silver fir in the northern Apennines. The forests of Camaldoli (CAM), La Verna (VER), and Sasso Fratino (SFR) are closely located and have similar site characteristics (Table 1; Figure 1) SFR has been strictly protected since 1959 (the core area where our study area is located) CAM and VER have had no harvesting and locally low-intensity forest tending Study areas that were relatively structurally uniform were selected in each forest based on their representativity and conservation status we selected 29–50 ha study areas in each forest that were relatively structurally uniform and representative of the current forest structure and 120 m for BGO) was superimposed on the 1:10.000 raster map resulting in a variable number of sampling plots ranging from 29 to 37 Classical forest structure attributes for living trees (basal area and density of snags having dbh > 47.5 cm) and regeneration (density of saplings divided by species) were used to assess the between-forest variability and the between-plot variability Other between-forest parameters were the species composition calculated as a proportion of a particular species on a broad basal area and the diameter distribution Between-plot variability was explored by using a multivariate approach. Two principal components analyses (PCAs) were performed to investigate the correlation structure among living trees, regeneration, and CWD attributes. The first PCA was performed on the Italian study areas only, and the second one was performed to compare the forest structure of Italian vs. Dinaric study areas. PCAs were performed using PC-ORD 7.10 (McCune & Mefford 1999) statistical packages and their statistical significance was tested by the Monte Carlo permutation method based on 10,000 runs with randomized data it results from the coexistence of monolayered dominant silver fir stands with a normal distribution and a dense intermediate-suppressed beech layer that has progressively been artificially established in recent decades Beech accounts for 55% of the trees but only 10% of the basal area Dominant trees are smaller (average of the 10 largest trees ha−1: 77 cm) than in VER and SFR because of past intensive management The volume of CWD (57 m3 ha−1) is mainly a consequence of the endogenous competition mortality observed in the last 50 years (only two snags and 1 log ha−1 with diameter > 50 cm) after the cessation of thinning The regeneration density (287 individuals ha−1) is low Diameter distribution in the five study areas the slope (closer to 100% and much higher than VER and CAM) reduces CWD accumulation in situ The regeneration density (943 individuals ha−1) in SFR is higher than that in CAM and VER The regeneration density (280 individuals ha−1) in VER is low and is less favorable for the ungulate wintering The two Dinaric study areas have similar forest structures and show relevant differences from the Italian ones The volume of living trees of Dinaric OGF is 994 m3 ha−1 in PER and 1,021 in BGO. The diameter distribution is a rotated sigmoid typical of the old-growth stage (Motta et al., 2015b) Beech accounts for 37% (PER) and 38% (BGO) of the basal area Dominant trees reach a relevant size and an average size (10 largest tree ha−1) of 117 cm in PER and 124 cm in BGO The volume of CWD in the Dinaric study areas is much higher than that in the Italian study areas with the values being 411 m3 ha−1 in PER and 375 in BGO The difference in the CWD quantity can be explained mainly by the critical incidence of large snags (respectively 103 ha−1 and 97 with a diameter of >50 cm in PER and BGO) and logs (respectively 46 ha−1 and 41 with a diameter of >50 cm in PER and BGO) The Shannon diversity index and diameter standard deviation are higher in the Dinaric study areas than in the Italian ones The regeneration density is also much higher in the Dinaric study areas than in the Italian study areas (2,313 individuals ha−1 in PER and 3,107 individuals in BGO) showing the continuity of the recruitment in the forest dynamics coherent from the old-growth stage characterized by continuous minor scale disturbances the regeneration is less affected by ungulate browsing (15% browsed silver firs in PER and 23% in BGO) The carbon stock in the Dinaric forests (aboveground biomass and CWD) is 25% higher in the Dinaric study areas than in the Italian ones The maximum ages reached by the dominant trees range from 164 (CAM) to 303 (SFR) years in the Italian sites (Table 3) The age in the Dinaric sites is much older reaching more than 480 years in both sites which represent two of the best-preserved old-growth forests in southern Europe we can hypothesize that the oldest trees are near their maximum biological age Release from suppression for the five study sites (gray bars: percent of trees showing abrupt growth release; dotted line: sample depth) The forest structures of the Apennine study areas are different, and this diversity is expressed by the distance between their centroids in the ordination environment (Figure 4) VER is characterized by lower basal area (BA) and high biodiversity related to both species (SH_sp) and structure (SH_dbh) CAM and SFR are characterized by a higher basal area (BA) but silver fir is dominant at CAM and beech at SFR Another considerable difference between the latter areas is the amount of regeneration (higher at SFR) and CWD (higher at CAM) Principal component analysis of 99 plots of 3 sites of the Italian Apennines (CAM By adding the two reference study areas (PER and BGO) to the ordination analysis, we observed a marked difference between the Apennine study areas and the two OGFs of the Dinaric Alps (Figure 5) The latter is characterized by a higher amount of CWD This multivariate comparison highlights the similarities between the two OGFs of the Dinaric Alps and their marked structural distance from the Apennine study areas Principal component analysis of 161 plots of 3 sites of the Italian Apennines (CAM La Verna) and 2 sites of the Dinaric Alps (PER Starting from the middle of the 20th century the State Forestry Agency made an extensive post-war restoration through the entire forest by planting silver fir in the clear-cut areas and of beech under the cover of the dominant silver fir which originated the current intermediate and suppressed beech layers The current monolayered structure of most of the Camaldoli study area reflects the central European silvicultural principles based on clear-cutting and dense artificial afforestation of silver fir and thinning of the monolayered stands introduced by Karl Siemon more than the Benedictine monastic approach The current irregular forest structure reflects the past sporadic but intense harvesting followed by some decades of strict protection Probably because of its importance for past charcoal production the beech dominates all the vertical layers and still shows signs of past coppicing Sporadic silver fir veteran trees surrounded by beech were probably left when the beech was coppiced as reserves due to the difficulty of transporting the trees out of the forest The chronology of the releases from suppression in the last decades shows that natural processes (small-scale disturbances) are slowly shaping the forest structure the management has been based on salvage low-intensity restoration loggings Even if it has always been managed with low intensity that has had a continuous forest cover without large clear-cuts or coppicing There was a significant difference between Benedictine and Franciscan rules and this different “spiritual” and “behavioral” attitude has substantially affected the landscape that is still visible today The productive but sustainable benedictine management model contrasted with the Franciscans’ more “natural” approach The history of SFR (located 3 km from Camaldoli and 16 km from La Verna) is slightly different for its different ownership and relative remoteness (located on the northern side of the Apennines with no road crossing the forest) and its slope steepness The forest structure has been more influenced by intense but sporadic harvesting and by local farmers more interested in firewood than timber Consequently, there was a higher incidence of beech coppiced, and many charcoal kiln platforms are still visible today. At the same time, the sporadic harvesting and the difficulties of wood extraction have allowed the conservation of some old and large trees. The last silvicultural intervention dates back to 1936, and in the last decades, the natural dynamics have shaped and partially overlapped the previous anthropogenic structure (Travaglini et al., 2012) All the studied Apennine forests, although they have been strictly protected for more than 60 years as is the case of SFR or have had in recent decades only low-intensity or sanitary interventions (CAM and VER), still have structural characteristics very different from the Dinaric old-growth forests (Figure 5) The Italian study areas have much higher living tree biomass than low-intensity managed forests (Motta et al., 2015b) and close to the amount of old-growth stands in SFR and CAM (Table 2) This amount is mainly due to the cessation/substantial reduction of harvesting in the last decades still there are significant differences with Dinaric OGFs where both beech and silver fir reach their biological age limits the Shannon diversity index and standard deviation of the diameter are higher in the Dinaric forests highlighting the presence of a wide range of development stages characterized by different tree sizes The studied forests represent the northern Apennines’ most important silver fir remains. The conservation of these forests is mainly due to the “monastic silviculture” that has preserved and even planted and spread the silver fir for economic and spiritual purposes (Agnoletti and Paci, 2001) Even if the three studied forests are relatively close and share similar site conditions their current structures are significantly different The differences are mainly due to past ownership and different monastic rules and spiritual attitudes The monks have created a cultural landscape and a peculiar biocultural diversity over the centuries even with other historical contributions (the most important one is due to the Bohemian forest engineer Karl Siemon who managed Camaldoli and most of the silver fir forests in the 19th century) There are currently substantial structural differences between Apennine forests and Dinaric old-growth forests mainly due to the amount and the quality of CWD The risk is that by applying almost exclusive biodiversity-centered management and setting difficult or even impossible-to-achieve biodiversity goals which is the greatest richness of most European parks The raw data supporting the conclusions of this article will be made available by the authors MR developed the conception and the method of the study GM made the multivariate ordination analyses All authors contributed to the article and approved the submitted version Thanks to Reparto Carabinieri per la Biodiversità di Pratovecchio (Pratovecchio All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher “Tuscany” in Italian historical rural landscapes Google Scholar Google Scholar Silver fir in Tuscany from XIV to XX century” in Le Sapin - Enjeux anciens Google Scholar Cultural values and forest dynamics: the Italian forests in the last 150 years CrossRef Full Text | Google Scholar CrossRef Full Text | Google Scholar The long way back: development of central European mountain forests towards old-growth conditions after cessation of management CrossRef Full Text | Google Scholar Structure and dynamics of a beech forest in a fully protected area in the northern Apennines (Sasso Fratino Ordini religiosi e modalità di rapporto col bosco: le fonti di Camaldoli e La Verna Google Scholar “La gestion des forêts par les ordres religieux: camaldoli vallombreuse et La Verne” in Abbayes et monastères aux racines de l'Europe Google Scholar Google Scholar “Monitoraggio compositivo e strutturale della foresta de La Verna (Italia - AR) attraverso la gestione selvicolturale dal 1890 a oggi” in Second international congress of Silviculture Designing the future of the forestry sector Ciancio (Firenze: Accademia Italiana di Scienze Forestali) Google Scholar “Cenni storici” in La Riserva Naturale Integrale di Sasso Fratino 50 anni di conservazione della biodiversità Bottacci (Pratovecchio: CFS/UTB Pratovecchio) Google Scholar La Riserva Naturale Integrale di Sasso Fratino Google Scholar Gap-phase dynamics in the old-growth Forest of Lom PubMed Abstract | CrossRef Full Text | Google Scholar Multi-proxy study of Holocene environmental change and human activity in the central Apennine Mountains What is unmanaged forest and how does it sustain biodiversity in landscapes with a long history of intensive forestry CrossRef Full Text | Google Scholar Legacies of past human activities on one of the largest old-growth forests in the south-east European mountains Wild ungulate overabundance in Europe: contexts CrossRef Full Text | Google Scholar The old charcoal kiln sites in central Italian forest landscapes Site and stand effects on coarse woody debris in montane mixed forests of eastern Italian Alps CrossRef Full Text | Google Scholar The cultivation of Castanea sativa (mill.) in Europe from its origin to its diffusion on a continental scale Structural and ecological characteristics of mixed broadleaved old-growth forest (Biogradska Gora - Montenegro) The value of long-term history of small and fragmented old-growth forests for restoration ecology Catholicism and conservation: the potential of sacred natural sites for biodiversity management in Central Italy CrossRef Full Text | Google Scholar Shrines in Central Italy conserve plant diversity and large trees Natural disturbance and stand structure of old-growth northern white-cedar (Thuja occidentalis) forests Identifying growth releases in dendrochronological studies of forest disturbance CrossRef Full Text | Google Scholar Is there a relation between ecological practices and spirituality Le vicende storiche e demografiche italiane come causa dei cambiamenti del paesaggio forestale Annali Accademia Italiana di Scienze Forestali 55 Google Scholar Google Scholar Impacts of changing climate and land use on vegetation dynamics in a Mediterranean ecosystem: insights from paleoecology and dynamic modeling IPCC (2006) “2006 IPCC guidelines for national greenhouse gas inventories” in A primer Prepared by the National Greenhouse Gas Inventories Programme Google Scholar Overview of the use of natural variability concepts in managing ecological systems Google Scholar Google Scholar Large-diameter trees control forest structure and function in successional temperate forests Risultati delle ricerche in foreste vergini europee Annali Accademia Italiana di Scienze Forestali 9 Google Scholar Long-term changes in Italian mountain forests detected by resurvey of historical vegetationdata Lindenmayer Some guiding concepts for conservation biology CrossRef Full Text | Google Scholar Quantifying the effect of sampling plot size on the estimation of structural indicators in old-growth forest stands CrossRef Full Text | Google Scholar Ecological importance of large-diameter trees in a temperate mixed-conifer Forest Marini Govigli From religion to conservation: unfolding 300 years of collective action in a Greek sacred forest CrossRef Full Text | Google Scholar Martin-Benito Development and long-term dynamics of old-growth beech-fir forests in the Pyrenees: evidence from dendroecology and dynamic vegetation modelling Google Scholar Large trees dominate carbon storage in forests east of the Cascade crest in the United States Pacific northwest "La foresta della Verna in Casentino (AR): influenza della gestione selvicolturale degli ultimi secoli sulla struttura della foresta" In: Congresso Nazionale di Selvicoltura: accademia Italiana di Scienze Forestali Google Scholar Mölder When beech strikes back: how strict nature conservation reduces herb-layer diversity and productivity in central European deciduous forests Morales-Molino Long-term responses of Mediterranean Mountain forests to climate change fire and human activities in the northern Apennines (Italy) Toward a definition of the range of variability of central European mixed Fagus-Abies-Picea forests: the nearly steady-state forest of Lom (Bosnia and Herzegovina) forest structure and regeneration in the Valbona Forest reserve spatio-temporal dynamics and disturbance regime of the mixed beech–silver fir–Norway spruce old-growth forest of Biogradska Gora (Montenegro) Development of old-growth characteristics in uneven-aged forests of the Italian Alps Growth trends and dynamics in sub-alpine forest stands in the Varaita Valley (Piedmont Italy) and their relationships with human activities and global change CrossRef Full Text | Google Scholar Structure and stand development in three subalpine Norway spruce (Picea abies (L.) karst.) stands in Paneveggio (Trento CrossRef Full Text | Google Scholar Tree rings reveal signs of Europe’s sustainable forest management long before the first historical evidence Müllerová Detecting coppice legacies from tree growth Gap disturbance regime in an old-growth Fagus-Abies forest in the Dinaric Mountains CrossRef Full Text | Google Scholar Google Scholar Disturbance regime of a cold temperate forest as deduced from tree-ring patterns: the Tantaré ecological reserve CrossRef Full Text | Google Scholar Foresta e monaci di Camaldoli: un rapporto millenario tra gestione e conservazione Google Scholar Comparative analysis of dendroecological methods used to assess disturbance events CrossRef Full Text | Google Scholar CrossRef Full Text | Google Scholar Protection gaps and restoration opportunities for primary forests in Europe Sarmiento-Mateos Designing protected areas for social–ecological sustainability: effectiveness of management guidelines for preserving cultural landscapes Scherzinger Qualitäts- ziele einer dynamischen Waldentwicklung Google Scholar Schweingruber presentation and interpretation of event years and pointer years in dendrochronology Google Scholar History of nature protection in the Sutjeska National Park CrossRef Full Text | Google Scholar Caratteri comparati delle abetine primarie delle Alpi dinariche e delle abetine secondarie delle Alpi orientali italiane Google Scholar structure and genetic dating of an old-growth beech-fir forest in the northern Apennines (Italy) Forest dynamics and disturbance regimes in the Italian Apennines CrossRef Full Text | Google Scholar van Beeck Calkoen Ungulate management in European national parks: why a more integrated European policy is needed The line intersect method in forest fuel sampling Google Scholar Changes in forest cover in the Foresta della Lama (Casentino forests National Park) from Karl Siemon and Anton Seeland 1837 forest management plan Land-use history as a guide for forest conservation and management CrossRef Full Text | Google Scholar The mid-Holocene extinction of silver fir (Abies alba) in the southern Alps: a consequence of forest fires Palaeobotanical records and forest simulations Investigating sacred natural sites and protected areas for forest area changes in Italy Sacred natural sites and biodiversity conservation: a systematic review Dukić V and Nola P (2023) Monastic silviculture legacies and current old-growthness of silver fir (Abies alba) forests in the northern Apennines (Italy) Received: 03 July 2023; Accepted: 06 November 2023; Published: 07 December 2023 Copyright © 2023 Motta, Garbarino, Berretti, Bono, Curovic, Dukić and Nola. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) *Correspondence: Renzo Motta, cmVuem8ubW90dGFAdW5pdG8uaXQ= by Gabe Katzman — More than 7,000 people were without power in Snohomish County on Sunday The Snohomish County Public Utility District's (PUD) outage map showed 7,203 customers affected by the outage at 2 p.m The main areas affected appeared to be near Silver Firs Only 15 customers with without power as of 8 a.m. Monday, according to the Snohomish PUD outage map KOMO News has reached out to the Snohomish County PUD about the cause of the outage The cause of the outage is not currently known To report an outage, head to the PUD website. highly curated editorial content brings attention to hidden gems Share LinkHere Are The 10 Richest Cities In WashingtonLists the 10 richest cities in Washington state based on median income and poverty rates a few of our counties have certain advantages like housing some of our larger corporations The places on this list are home to some of the wealthiest people in the state—so if you’re considering moving to one of them After researching and checking out HomeSnacks we've determined that the following towns are the 10 richest cities in Washington The lake for which the town is named is also a beautiful place to visit MS / YelpSilver Firs, which you’ll find in Snohomish County near Mill Creek has a median income of $102,480 and a poverty level of 3.6% The 22,400 people who live in this lovely place are definitely doing well The $110,456 median income and 5% unemployment rate make it 10th on the list of the richest areas in Washington state Choose your stateAlabamaAlaskaArizonaArkansasNorthern CaliforniaSouthern CaliforniaColoradoConnecticutDelawareFloridaGeorgiaHawaiiIdahoIllinoisIndianaIowaKansasKentuckyLouisianaMaineMarylandMassachusettsMichiganMinnesotaMississippiMissouriMontanaNebraskaNevadaNew HampshireNew JerseyNew MexicoNew YorkNorth CarolinaNorth DakotaOhioOklahomaOregonPennsylvaniaRhode IslandSouth CarolinaSouth DakotaTennesseeTexasUtahVermontVirginiaWashingtonWest VirginiaWisconsinWyomingSubscribe... Enjoy your own private fishing pond and then head to one of Missouri's underrated fishing spots with a stay at this cozy cabin. Thanks for subscribing. We’ll see you in your inbox! The dates displayed for an article provide information on when various publication milestones were reached at the journal that has published the article activities on preceding journals at which the article was previously under consideration are not shown (for instance submission All content on this site: Copyright © 2025 Elsevier B.V. Metrics details At the 1000 km geographical distance in Dinaric montane forests of silver fir (Abies alba Mill.) and European beech (Fagus sylvatica L.) the tree response from the north-western sites towards southern warmer and dryer sites was performed during three consecutive growing seasons (2011 positioned in uneven-aged beech and fir forests above 800 m along the geographical gradient the physiological and morphological response to light intensity were measured in predefined light categories based on the analysis of hemispherical photos Radial growth was analysed on all plots and compared to precipitation Analysis showed a decrease in the cumulative precipitation and no change in temperature between plots Beech was most efficient in the open area light conditions while fir proved most efficient under shelter Physiological response for beech increased towards SE and reached its maximal values in the middle of transect while fir’s response decreased from the NW towards SE Tendency to plagiotropic growth decreased from NW to SE in both species Growth response to climatic parameters is weak stronger in fir than in beech and decreasing towards SE It is a large tree important for site productivity which forms many special habitats as a veteran or slow decomposing dead tree Fir is economically much appreciated and the most important conifer tree species within the Dinaric region the increasing atmospheric CO2 content and higher temperatures are expected to result in favourable effects on forest growth and wood production while increasing drought and disturbance risks are likely to outweigh positive trends in southern and eastern Europe the studied tree response from the southern warmer and dryer sites may serve as a most probable future prediction for the same species-response on currently less extreme sites Our aim was (1) to compare physiological and morphological responses of beech and fir along the defined 1000 km geographical gradient (2) to evaluate differences in same light categories of both species between managed and old growth forest and (3) to verify the connection between radial growth of adult stand with ecophysiological and morphological traits of both species along the gradient with several protected old-growth remnants scattered throughout the area Research area and the location of plots Boxes (A–D) represent regions with extracted gridded meteorological data Assimilation response was measured in saplings of fir and beech in June and July during three consecutive growing seasons (2011 Age of the trees varied between 5–12 years Fresh leaves were weighed and scanned for the leaf area Leaves were dried at 105° for 24 hours until constant weight and weighed for the dry mass in the lab to provide leaf mass per area (LMA) [g/m2] The light-response was measured with an LI-6400 portable system on at least four leaves/locations per tree located in the upper third of the tree-crown Light saturation curves were established to compare the net assimilation (Amax) in young beech and fir trees in the same light conditions All assimilation measurements were performed in field at a constant temperature of the measurement block (20 °C) airflow 500 µmols−1 and different light intensities: 0 Maximum assimilation (Amax) rates for the light saturation curves were used for comparisons of responses between different light categories and plots The limiting value of light was defined after measurements of the ratio after three consequential growing seasons (2011 the values under same light-intensity conditions were compared between plots (how closed/open the mature stand was) Plagiotropic behaviour between different plots was assessed by comparison of data into an exponential-decay-3 parameter curve (1) Y is the quotient between the length (l) and the height of saplings (h) and A We used the same software for quality control of measured tree-ring width sequences Tree ring series were then visually and statistically cross-dated using PAST-5 Amax and Φ were tested with the two-way ANOVA with species (beech and fir) and light (open Analyses of variance (ANOVA) and HSD Tuckey post hoc test were used after testing data to meet conditions of normality p < 0.01 (**) and p < 0.001 (***) were considered significant Data analysis and correlation between measured variables was performed with Statistica data analysis software system (2011) Average air temperature and total precipitation within the April-September (1985–2015) growing period on studied plots (left) and differences in average cumulative precipitation (mm) and in average air temperature (°C) between 1995–2004 and 2005–2015 windows during the same growing period (right) When comparing precipitation and temperature values of two different consecutive referential periods 1995–2004 and 2005–2015 within April-September, the drop of total precipitation and rise of average annual air temperature was confirmed (Fig. 2 evident decrease of precipitation between periods amounted to between 10–20 mm with the exception of plots 10 and 11 while the temperature rise ranged between 0.33°–0.65 °C on all studied plots Foliar nitrogen and leaf mass per area; bars are standard errors Assimilation (Amax) - left and Quantum yield (Φ) - right in three different light categories for beech and fir on studied plots Values of different light categories belonging to the same plot are shifted to avoid overlapping Differences in Amax and Φ between same light categories were significantly different for both beech and fir (Table 3) Different response in beech and fir is confirming our former research showing increasing Φ in beech with increasing light intensity and the opposite Differences are even more pronounced along the geographical gradient showing increase in Φ for beech towards the SE in all light categories and decrease in Φ for fir Post-hoc analysis confirmed statistically significant differences between all categories of light for both Amax and Φ except on locations with old growth reserves where no significance has been confirmed between forest edge and open light categories for both beech and fir Maximal Φ for beech was observed in open light Evident shift of Φ in the edge category towards the open light in all old growth reserves was observed for both species compared to managed forests, while in managed forests the distribution of light categories was more even (Fig. 4) Amax and Φ for both fir and beech confirmed stronger relation between average annual precipitation than between average annual temperature. Relation between Φ and temperature was more pronounced for fir than beech (Table 4) Light intensity at the deflection point (DP) Triggering light intensity (decrease in shade tolerance) increased from NW towards SE (from plot No Shaded parts represent old growth reserves Relation between DP and precipitation along the studied range was more pronounced for the growing season (R2beech = 0.82 and R2fir = 0.75) than for the whole year-period (R2beech = 0.64 and R2fir = 0.67) Stronger relation between the morphological response (DP) and temperature on the whole gradient was confirmed more for the growing period (R2beech = 0.36; R2fir = 0.26) than for the entire year (R2beech = 0.25; R2fir = 0.12) Radial growth response for fir in four selected regions (A–D) to different climatic parameters - average monthly temperature Palmer Drought Severity Index (PDSI) and 3-month Standardized Precipitation Index (SPI-3) Dark circles and dark bars indicate statistically significant bootstrapped correlations Temperature (T) influenced the growth of fir in regions A and B correlation between p and radial growth decreases while correlation between SPI3 and PDSI are the same as in region A We believe these results indicate tree growth as more sensitive to long-term rather than short term water deficit we confirmed only weak correlation between climate variables and fir radial growth only PDSI shows correlation between February PDSI (till September of the preceding year) and radial growth Weak negative correlations between T and radial growth in August and September indicate that water required for the growth is accumulated during the winter in a form of snow and slowly released during the growing period no significant correlations between any of the studied climatic variables and radial growth were confirmed Only two weak correlations between T- a positive in December of the preceding year and a negative in September of the year of ring formation were evident Both were weak and on the edge of significance Radial growth response to climate for beech in four selected regions (A–D) (see Fig. 6) Comparison of tree growth response to climate between managed and old-growth reserves did not confirm any differences; management of studied forests is evidently close-to-natural processes in old-growth reserves without significant disturbances caused by forest management we identified altogether 53 pointer years (PY) for fir and 50 for beech 26 PY were positive and 27 were negative; for beech 27 years were positive and 23 were negative with B and C having significantly more than regions A and D We couldn’t find only a single PY year that would be common to all four regions and both tree species Only one positive PY (1958) was common to beech in all four regions for example 1930 was positive for fir and beech in regions B Hot and dry 2003 is only visible in tree rings of fir in regions B and D while hot and dry 2006 is visible only in fir in region A beech seems to be more drought tolerant than fir who confirmed increase in proportion of chamaephytes hemicryptophytes and therotypes towards SE in mesophylous beech forests of SE Europe We relate comparable amount of nitrogen content in leaves on all plots with similar temperature and site conditions Φ for beech was highest in the central range (Bosnia and Herzegovina) and for fir in the NW part of the transect (Slovenia gaps are created after disturbances and present an opportunity for overgrowing of the present tree species below which plagiotropic growth is evident In old growth reserves (Fig. 4 - No plagiotropic growth in beech and fir was triggered by smaller light intensities (DP) than in managed forests Assimilation rates (Amax) and efficiency (Φ) were also higher than on neighbouring managed forest sites Fir growth response to climate was slightly stronger than in beech Both variables - T and p have stronger influence on growth of fir than on beech Climate signal in fir diminished from NW to SE where only drought indices remain significant while beech response to climate was weaker on all plots and diminished who studied beech growth and climate response in a relatively dense network of beech sites in Serbia and Bosnia & Herzegovina confirmed that beech responded to climate only at a lower and in some cases also at the upper timberline Beech in the optimal altitudinal distribution range shows weak response to climate and mainly responses to other Our study confirms this significant relation in regions A Fir response to climate has a clear spatial element: in NW July T and p (together with drought indices) were the most influential factors in region B a wider time frame of the response ranging from May till August for p while in region C the main driving factors are p in May and PDSI indicating importance of water availability at the beginning of the growth only PDSI and SPI-3 correlated with growth confirming again water availability as a major factor influencing the radial growth Disadvantages of uneven-aged forestry include the reliance on shade tolerant species which can be hampered by climatic conditions of open areas created by disturbances Physiological and morphological differences are even more pronounced along the geographical gradient showing efficiency increase in beech towards the SE in all light categories and decrease in fir Morphologic changes indicate reduced shade tolerance towards SE for both species Reasons for such response might be in the natural range of the species distribution or better plasticity in beech compared to fir Fir in the SE part reaches its southernmost range of natural distribution where droughts and precipitation deficit are more pronounced compared to the NW region of the study Physiologic and morphologic responses within growth areas (A–D) along the studied gradient Our findings add evidences of divergent tree response in the Mediterranean basin and show a gradual transition between forests where positive (temperate) and negative (Mediterranean) growth trends dominate We believe that preservation of uneven-aged structure emphasis on fir regeneration and reduction of ungulates present key steps for further stability in those close-to-nature mixed forest ecosystems European Atlas of Forest Tree Species Publ https://w3idorg/mtv/FISE-Comm/v01/e01493b (2016) Ecology and silviculture of silver fir (Abies alba Mill.): A review Silvicultural tools to develop irregular and diverse forest structures Ecological Requirements of Abies alba in the French Alps Derived from Dendro Ecological Analysis Increasing aridity is enhancing fir (Abies alba Mill.) water stress in its south-western distribution limit Ugibanje i obnavljanje jele u prebornim šumama Gorskog Kotara Dendroecological assessment of the complex causes of decline and recovery of the growth of fir (Abies alba Mill.) in Southern Germany Waldschadenuntersuchungen am Stammkern von erwachsenen Tannen im dinarischen Tannen - Buchen - Wald Structural dynamics and synchronous silver fir decline in mixed old-growth mountain forests in Eastern and Southeastern Europe Tree rings indicate different drought resistance of native (Abies alba Mill.) and a nonnative (Picea abies (L.) Karst.) species co-occurring at a dry site in Southern Italy Contribution of working group II to the fourth assessment report of the intergovernmental panel on climate change Local adaptation in European firs assessed through extensive sampling across altitudinal gradients in southern Europe Primary production in Mediterranean-climate ecosystems regenerating after fire and longer lasting heat waves in the 21st century Impacts of climate change on natural forest productivity–evidence since the middle of the 20th century Black pine (Pinus nigra Arn.) growth divergence along a latitudinal gradient in Western Mediterranean mountains Thermal acclimation of photosynthesis: a comparison of boreal and temperate tree species along a latitudinal transect Predicting the impacts of climate change on the distribution of species: are bioclimate envelope models useful Evaluating the sources of potential migrant species: implications under climate change Co‐occurrence patterns of trees along macro‐climatic gradients and their potential influence on the present and future distribution of Fagus sylvatica L Building the niche through time: using 13,000 years of data to predict the effects of climate change on three tree species in Europe Radial growth response of four dominant boreal tree species to climate along a latitudinal gradient in the eastern Canadian boreal forest A latitudinal gradient in tree growth response to climate warming in the Siberian taiga Distinct effects of climate warming on populations of silver fir (Abies alba) across Europe structure and abundance of silver fir (Abies alba Mill.) indicate its decline Depression and growth recovery of silver fir in uneven-aged Dinaric forests in Croatia from 1901 to 2001 Forestry: An International Journal of Forest Research 88 Placing unprecedented recent fir growth in a European‐wide and Holocene‐long context Frontiers in Ecology and the Environment 12 The prospects of silver fir (Abies alba Mill.) and Norway spruce (Picea abies (L.) Karst) in mixed mountain forests under various management strategies Karte der natürlichen Vegetation Europas/Map of the Natural Vegetation of Europe Some morphological characteristics of the Dinaric Karst A comparative analysis of recent changes in Dinaric uneven-aged forests of the NW Balkans in different silvicultural systems of the high Dinaric karst Updated high‐resolution grids of monthly climatic observations–the CRU TS3 Physiological plant ecology: ecophysiology and stress physiology of functional groups silver fir and Norway spruce advance regeneration to increased light levels following natural disturbance Gap size and position influence variable response of Fagus sylvatica L Different Respones to Gaps Among Shade‐Tollerant Tree Species Norway spruce conversion: options and consequences ATRICS - a new system for image acquisition in dendrochronology Bunn, A. G. A dendrochronology program library in R (dplR). Dendrochronologia 26, 115–124, https://doi.org/10.1016/j.dendro.2008.01.002 (2008) Zang, C. & Biondi, F. treeclim: an R package for the numerical calibration of proxy-climate relationships. Ecography 38, 431–436, https://doi.org/10.1111/ecog.01335 (2015) Geographical and ecological differentiation of F agus forest vegetation in SE Europe Foliar morphological and physiological plasticity in Picea abies and Abies alba saplings along a natural light gradient Comparison of new foliar nutrient thresholds derived from van den Burg’s literature compilation with established central European references Soil water balance performs better than climatic water variables in tree species distribution modelling Syntaxonomische Revision der südmitteleuropäischen Buchenwälder Syntaxonomical revision of the beech forests of southern Central In Silver fir (Abies alba Mill.) in Croatia (ed B Prpić) 269-277 (Akademija šumarskih znanosti Regeneration growth in different light environments of mixed species and needle structure of silver fir (Abies alba Mill.) seedlings under different canopies in different categories of forest edge–vertical abundance in two silvicultural systems Functional ecology of advance regeneration in relation to light in boreal forests Ergebnisse der Buchen-Voranbauversuche im Harz unter besonderer Berücksichtigung der lichtökologischen Verhältnisse Waldumbau von Nadelholzreinbeständen in Mischbestände treeclim: an R package for the numerical calibration of proxy‐climate relationships Apical dominance ratio as an indicator of the growth conditions favouring Abies alba natural regeneration under Mediterranean environment Morphological plasticity in seedlings of three deciduous species under shelterwood under-planting management does not correspond to shade tolerance ranks Main patterns of variability in beech tree-ring chronologies from different sites in Slovenia and their relation to climate Hacket-Pain, A. J. & Friend, A. D. Increased growth and reduced summer drought limitation at the southern limit of Fagus sylvatica L., despite regionally warmer and drier conditions. Dendrochronologia 44, 22–30, https://doi.org/10.1016/j.dendro.2017.02.005 (2017) Stjepanović, S. et al. The Impact of Adverse Weather and Climate on the Width of European Beech (Fagus sylvatica L.) Tree Rings in Southeastern Europe. Atmosphere 9, https://doi.org/10.3390/atmos9110451 (2018) Stojanović, D. B., Levanič, T., Matović, B., Stjepanović, S. & Orlović, S. Growth response of different tree species (oaks, beech and pine) from SE Europe to precipitation over time. Dendrobiology 79, 97–110, https://doi.org/10.12657/denbio.079.009 (2018) Canham, C. D., Murphy, L., Riemann, R., McCullough, R. & Burrill, E. Local differentiation in tree growth responses to climate. Ecosphere 9, e02368, https://doi.org/10.1002/ecs2.2368 (2018) Dendroecological assessment of the complex causes of decline and recovery of the growth of silver fir (Abies alba Mill.) in Southern Germany Bosela, M. et al. Effects of post-glacial phylogeny and genetic diversity on the growth variability and climate sensitivity of European silver fir. Journal of Ecology 104, 716–724, https://doi.org/10.1111/1365-2745.12561 (2016) The influence of monthly and periodical meteorological parameters on the radial growth of Silver fir Nagel, T. A., Levanič, T. & Diaci, J. A dendroecological reconstruction of disturbance in an old-growth Fagus-Abies forest in Slovenia. Annals of Forest Science 64, 891–897, https://doi.org/10.1051/forest:2007067 (2007) Dorado-Linan, I. et al. Geographical adaptation prevails over species-specific determinism in trees’ vulnerability to climate change at Mediterranean rear-edge forests. Glob Chang Biol, https://doi.org/10.1111/gcb.14544 (2018) Explaining the low‐temperature range limits of temperate tree species Comparing close-to-naturesilviculture with processes in pristine forests: lessons from Central Europe Silviculture in an uncertain world: utilizing multi-aged management systems to integrate disturbance Long-term changes of structure and tree species composition in Dinaric uneven-aged forests: are red deer an important factor Ungulate herbivory modifies the effects of climate change on mountain forests Download references The authors acknowledge the financial support from the Slovenian Research Agency (research core funding P4-0107 Program research group “Forest Biology Ecology and Technology” at the Slovenian Forestry Institute and projects V4-1820 J4-5519 “Paleoclimate data enhances drought prediction in the W Balkan Region” and J4-8216 “Mortality of lowland oak forests - consequence of lowering underground water or climate change?” Authors express their sincere gratitude to R Special thanks are due to Dr Nenad Potočić BSc in Engineering Nail Kryeziu and Prof Dr Mitko Karadelev performed sampling and did the analysis of physiological and morphological response The authors declare no competing interests Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations Download citation DOI: https://doi.org/10.1038/s41598-019-52670-z Anyone you share the following link with will be able to read this content: Sorry, a shareable link is not currently available for this article. Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily. ‘I could not believe it when I saw what happened’ A historic tree in Ramsey planted to mark the visit of Queen Victoria and Prince Albert has fallen victim to Storm Darragh. Two silver firs were planted at Claughbane farmhouse in 1847 when Victoria and Albert visited the island – one for each royal. These trees were even mentioned in the poem ‘The Home Place’ by celebrated Manx poet Josephine Kermode - known by her pen name Cushag - when she lived at Claughbane. The tree planted for Prince Albert fell during a storm on January 22, 1990, and, sadly, the one for Queen Victoria was toppled overnight on Saturday into Sunday despite being around 100ft high. Jasmine Lilleby, whose mum lives at Claughbane, is currently visiting and was there at the weekend. She is sad to see the tee fall but admits it could have been worse. She said: ‘I could not believe it when I saw what happened. It is very sad and I had a few moments yesterday. ‘The garden looks so different now. It was the focal point of the whole garden. If Josephine described them as Herculean back in approximately 1905, you can imagine the size of this tree today. ‘Luckily, it feel away from the property into the other trees and stopped just at the border. Had it fallen the other way it would have hit the house and probably the bedroom in which I’m sleeping. ‘Claughbane is well known in Ramsey and the community here probably know about the trees too. So it is a real loss.’ The Isle of Man felt the full force of Storm Darragh over the weekend as winds of up to 80mph downed trees, shut roads and left homes without power. The Department of Infrastructure (DoI) were called out to over 160 locations across the island as staff worked to clear more than 200 downed trees. An amber weather warning for severe winds, issued by the Ronaldsway Met Office, came into effect at 3am on Saturday morning (December 7) and remained in place until 11.59pm on Saturday evening. The worst of the storm hit the island at 4am on Saturday morning as winds tore down a number of trees, blocking a number of areas. Tel: 01624 695695[email protected]Follow us Further Links Owned or licensed to Tindle Newspapers Ltd. | Independent Family-Owned Newspapers | Copyright & Trade Mark Notice & 2013 - 2025 Volume 3 - 2020 | https://doi.org/10.3389/ffgc.2020.00036 This article is part of the Research TopicDrought-induced Forest and Tree MortalityView all 4 articles Forest dieback is manifested as widespread loss of tree vigor Forest dieback is becoming increasingly frequent and extended This is the case of the south-western Spanish Pyrenees where keystone species such as Silver fir reach their xeric and southern distribution limits While dieback of this species has been widely documented in this area we still lack methodologies to forecast the vulnerability of these forests in response to increasing drought stress so as to anticipate their potential dieback in the future Here we study multiple features of Silver fir forests and trees to evaluate whether previous growth rates and their growth trends are valid predictors of forest dieback we validate our methodology revisiting two Silver fir sites sampled two decades ago The defoliation degree was strongly related with radial growth and growth trends differed between moderately to highly defoliated trees and non-defoliated trees those in which 25% of the sampled trees showed defoliation > 50% were located at low elevation and received less rainfall in summer than forests showing no dieback Trees showing high defoliation presented lower growth rates than non-defoliated trees we ratified that defoliation has increased considerably over the last two decades in one of the two revisited sites but we were unable to accurately forecast growth trends in both sites particularly in the site not showing dieback The retrospective assessment of growth rates and trends offers valuable information on the vulnerability of Silver fir trees to drought we are still far from being able to forecast the vulnerability of Silver fir forests to increasing drought A systematic monitoring of growth across a wide tree-ring network of sites might provide valuable information to advance in this direction it remains unclear why some Silver fir populations are more vulnerable to drought than others and which variables can be used as early warning signals to identify and forecast forest vulnerability dendrochronology provides a useful tool to place in a temporal framework whether growth trends can inform on tree vulnerability and whether this vulnerability results in realized dieback at the stand level Two of these forests were revisited in 2019 to study their evolution 20 years later and dendrochronological methods were applied in them have lower growth rates than non-declining trees; (ii) the occurrence of negative growth trends as a consequence of the loss of resilience capacity to drought is more evident in defoliated trees and indicates their vulnerability to drought; and (iii) long-term negative growth trends can be used to evaluate forest dieback at the stand level calcic cambisols and eutric cambisols dominate in the study sites Characteristics of the studied silver fir stands Low SPEI values were observed for the years 1986–1987 The sites were sampled between 1999 and 2000 a 500-m long and 20-m wide belt transect (0.1 ha) was sampled oriented around the contour lines in a representative zone of the stand Between 10 and 15 dominant and codominant individuals were selected to represent the main conditions of the stand We measured the size (diameter at breast height; dbh) and height of each tree and measured the orientation elevation and slope of the terrain in which the tree was located We also estimated tree recent vigor by observing the abundance of epicormic shoots along the main stem and presence of abnormal growth in the crown apex (e.g. “stork’s nest,” dead and broken branches defoliation); mistletoe abundance (Viscum album L.) in the crown; and cone production based on the estimated number of cone rachises observed in the uppermost crown for the 1999 and 2000 crops Each tree was evaluated visually to estimate the percentage of defoliation in five classes based on the percentage of crown defoliation (Müller and Stierlin, 1990): class 0 0–10% defoliation (non-declining tree); 1 >91% defoliation or only retaining red needles (recently dead tree) The last tree ring they formed at 1.3 m was dated before the sampling year using dendrochronological methods we sampled as many declining trees as there were within the selected 0.1 ha belt transect based on the percentage of trees with severe defoliation (>50% crown defoliation) In addition, we measured the number and dbh of all trees and shrubs with a height greater than 1.3 m found within a circular plot 7.62 m in radius placed around each subject tree. After that, we described the immediate neighborhood of each tree (i) as related to all its measured neighbors (j) using the Lorimer (Li) competition index (Lorimer, 1983) The data obtained from this field sampling were also used to estimate the mean density (stems ha–1) and basal area (m2 ha–1) of Silver fir in each stand. Finally, we also estimated the richness and diversity of the main vascular, woody plant species within the circle of 7.62 m radius around each subject sampled tree and calculated the Shannon–Wiener diversity index (Magurran, 1988) a drought index which accounts for temporal differences in drought severity as a function of temperature and precipitation accounting from three to 12 months before June) Negative and positive SPEI values indicate dry and moist conditions The percentage growth change filter of Nowacki and Abrams (1997) was applied to identify abrupt growth changes (releases) for the 1950–1999 period we calculated the ring-width medians of subsequent 10-year periods along all the individual growth series the percentage of positive (PGC) growth change was defined as: Releases were defined as those years with PGC > 75% in at least two radii of each sampled tree. Finally, ring widths were converted to basal area increments (BAI, cm2 year–1) assuming a circular outline of stems (Visser, 1995) as: where R is the radius of the tree and t is the year of tree ring formation. BAI is commonly assumed to be a more meaningful indicator of tree growth than ring width because it removes variation in radial growth attributable to increasing circumference while preserves long- and short-term changes in growth (LeBlanc et al., 1992) We used a Principal Component Analysis as the starting configuration for the iterative fitting procedure of the NMDS and set 100 as the maximum number of iterations noting the stress values obtained in the ordinations we chose the number of dimensions equal to two to yield optimal ordinations Values are given as means ± standard errors throughout the text We compared the defoliation patterns and the growth in the two revisited stands (BA and CA) The Kruskal–Wallis Rank Sum Test was used to compare tree dbh and their defoliation degree between sites and sampling periods Simple correlation analyses were used to compare BAI of trees sampled in 1999–2000 and in 2019 for the period 1965–2000 we used the GAMM of BAI to project the growth of the trees into the 2001–2016 period we used the data of the trees sampled in the 2019 campaign we compared the projected and the observed BAI of stands resampled in 2019 Descriptive statistics of the tree-ring width and basal area increment series basal area increment) comparisons between non-declining and declining Silver fir trees (A) and trajectories of selected non-declining silver fir forests (FA and BA sites) and those showing dieback (PE The dark line represents the average BAI over all the individuals sampled in the stand and the shaded areas show the 95% confidence intervals for the mean The dashed line (secondary right y axis) represents the number of trees sampled in each stand Blue and brown colors are used to differentiate the non-declining from declining stands showing dieback respectively The first and second NMDS axes accounted for a 26 and 14% of the variance in the data, respectively (Figure 3A). Tree defoliation was positively related to (in decreasing order of importance): presence of abnormal growth features in the crown apex, mistletoe abundance, winter precipitation, tree age, and the frequency of growth releases (Figure 3B) Defoliation was negatively associated with tree-ring width and summer precipitation during 1990–1994 A stand with a high frequency of growth releases was more likely to be more defoliated Stands with higher summer precipitation and tree-ring width during 1990–1994 were less likely of being defoliated Main variables based on tree-level data which are related to forest decline as displayed in the ordination diagram based on the first two NMDS dimensions (A) and the ranking of those most highly related with crown defoliation (B) The lower graphs shows the Spearman correlation (rs) of tree variables and defoliation (n = 360 trees; white bar The uppermost scatter plot shows the relationship between the first NMDS axis scores and mean tree-ring width for the 1990–1994 period (note the low growth of an old but undefoliated tree indicated with the arrow) Trees are represented according to their crown defoliation (filled symbols crown > 50% defoliation; empty symbols The variables scores have been displaced to improve clarity Variables and their abbreviations are as follows: age presence of abnormal growth features in the crown apex; BA basal area in the neighborhood of each sampled tree; competition percentage of total annual precipitation recorded during fall/summer/winter; h mean tree-ring width/index for the 1990–1994 period; N summer precipitation recorded during the 1990–1994 period; release number of releases during the past five decades; soil indicating marked growth reductions in those trees Summary of the Generalized additive mixed model selected to predict basal area increment as a function of drought (SPEI03 tree diameter at breast height (dbh) and tree age at 1.3 m Figure 4. Observed growth trends for trees with different defoliation degree (A) and the effect of year on basal area increment (BAI) (B). The effect of year on BAI was dependent on defoliation according to the generalized additive model selected (Table 3) Different colors are used to represent the effect of year on BAI at different defoliation classes (0 to 5 from low to complete defoliation; see the tree sketches) Blue and brown colors differenciate non-declining (defoliation degree 0–2) from declining trees (3–5) Values close to zero indicate no influence of year on BAI Shaded areas represent standard errors for the mean and the effects in (A,B) respectively Dieback in the CA site has intensified over the last two decades since the percentage of trees showing complete defoliation or recently dead has increased from 0 to 21% in site BA no defoliation was observed in the 1999–2000 and 2019 samplings no differences in defoliation degree between BA and CA were found when data from the 1999–2000 sampling was compared (χ2 = 2.02; P = 0.16) significant differences in defoliation between these sites were observed when data from the 2019 sampling were compared (χ2 = 14.50; P < 0.01) The projection of BAI for the period 2000–2016 according to the GAMM fitted to the BAI of the 1999–2000 sampling data showed negative growth trends in both the CA and BA sites (Figure 5) We found a significant positive relationship between the observed and the projected BAI series for the period 2000–2016 in both CA (r = 0.36; P < 0.01) and BA (r = 0.68; P < 0.01) sites we did not find significant differences at the stand level neither in CA nor in BA basal area increment) trajectories in a non-declining (A site BA) Silver fir site and a showing dieback (B Black lines and gray areas represent the mean BAI and its 95% confidence intervals (CIs) Blue and brown lines and corresponding shaded areas represent the mean BAI and 95% CIs of the trees sampled in 2019 in the non-declining and the silver fir stand showing dieback respectively The purple line and dashed area represents the mean of the projected BAI (and 95% CIs) according to the generalized additive mixed effect model While we found a good correlation between observed and forecasted BAI values in the non-declining BA stand the results were less robust in the CA stand showing dieback These results emphasize that a single model of growth is not robust enough to project the strong variability in growth between trees and years while negative growth trends may inform about vulnerability at the tree level within stands they do not provide a tool to forecast stand dynamics in response to recent warming we encourage the continuous monitoring of tree defoliation and the updating of growth data in similarly vulnerable tree populations as a tool to better understand how growth trends can help us better forecast silver fir decline The extraordinary convergence of these two extreme events can be the explanation for the widespread dieback of several populations are reliable indicators of dieback at the tree level The lack of influence of April temperature can be explained because its effect can be partially accounted for the drought index potential biotic interactions with other tree species (e.g. album) were omitted for the sake of simplicity and to avoid overfitting the model we still need to answer which forests are more vulnerable and how can we anticipate their decline monitoring those sites that were sampled two decades ago may provide very valuable information and enhance our ability to forecast its vulnerability monitoring and updating crown defoliation and combining those data with a retrospective quantification of radial growth in trees of different vigor (defoliation classes) are useful tools to forecast forest vulnerability in response to drought stress We applied these ideas to the recent dieback of Silver fir forests in some Pyrenean sites We found that: (i) declining growth patterns are good indicators of dieback in Silver fir and (ii) revisiting study sites where dieback and defoliation had been previously monitored helps to better forecast the loss of tree vigor Negative growth trends in defoliated individuals started years before defoliation can be observed those individuals displaying very negative growth trends within stands can be considered vulnerable Sites showing dieback were clustered in the western part of our study area where summer precipitation is lower than in eastern sites where defoliation rates and growth decreases were lower than in sites at higher elevations and showing not dieback All datasets generated for this study are included in the article/Supplementary Material All authors developed the original idea of the study carried out the field sampling and tree-ring measurements and contributed to discussing and editing the final text This study was supported by projects FunDiver (CGL2015-69186-C2-1-R) and FORMAL (RTI2018-096884-B-C31) from the Spanish Ministry of Science GS-B was supported by a Spanish Ministry of Economy Industry and Competitiveness Postdoctoral grant (FJCI 2016-30121; FEDER funds) The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/ffgc..00036/full#supplementary-material On underestimation of global vulnerability to tree mortality and forest die-off from hotter drought in the Anthropocene Google Scholar A global overview of drought and heat-induced tree mortality reveals emerging climate change risks for forests Ecology and ecophysiology of circum-Mediterranean firs in the context of climate change CrossRef Full Text | Google Scholar Silver fir decline in the Vosges mountains (France): role of climate and silviculture Google Scholar Temperate forest trees and stands under severe drought: a review of ecophysiological responses adaptation processes and long-term consequences Placing unprecedented recent fir growth in a European-wide and Holocene-long context Model Selection and Multimodel Inference: a Practical Information-Theoretic Approach Google Scholar Evolución de abetares del Pirineo aragonés Google Scholar Early-warning signals of individual tree mortality based on annual radial growth A synthesis of radial growth patterns preceding tree mortality “The multiple factors explaining decline in mountain forests: historical logging and warming-related drought stress is causing silver-fir dieback in the Aragón Pyrenees,” in High Mountain Conservation in a Changing World Synergistic effects of past historical logging and drought on the decline of Pyrenean silver fir forests Forest growth responses to drought at short- and long-term scales in Spain: squeezing the stress memory from tree rings To die or not to die: early-warning signals of dieback in response to a severe drought The impact of a needleminer (Epinotia subsequana) outbreak on radial growth of silver fir (Abies alba) in the Aragón Pyrenees: a dendrochronological assessment Google Scholar Chorological maps for the main European woody species Árboles y Arbustos de la España Peninsular Google Scholar Tree growth as indicator of tree vitality and of tree reaction to environmental stress: a review CrossRef Full Text | Google Scholar Redefining temperate forest responses to climate and disturbance in the eastern United States: new insights at the mesoscale An evaluation of errors in tree age estimates based on increment cores in Kahikatea (Dacrycarpus dacrydioides) Google Scholar Irreversible impact of past land use on forest soils and biodiversity doi: 10.1890/0012-9658(2002)083[2978:iioplu]2.0.co;2 CrossRef Full Text | Google Scholar Google Scholar Google Scholar constrain European beech and Silver fir growth in their southern distribution limits Forest resilience to drought varies across biomes Aleppo pine forest from across Spain show drought-induced growth decline and partial recovery Hernández Biotic factors and increasing aridity shape the altitudinal shifts of marginal Pyrenean silver fir populations in Europe On the increased frequency of Mediterranean drought CrossRef Full Text | Google Scholar Computer-assisted quality control in tree-ring dating and measurement Applying metric and nonmetric multidimensional scaling to ecological studies: some new results CrossRef Full Text | Google Scholar Google Scholar Prevalence of individual-tree growth decline in red spruce populations of the southern Appalachian Mountains CrossRef Full Text | Google Scholar Silver fir defoliation likelihood is related to negative growth trends and high warming sensitivity at their southernmost distribution limit CrossRef Full Text | Google Scholar Tests of age-independent competition indices for individual trees in natural hardwood stands CrossRef Full Text | Google Scholar Increasing aridity is enhancing silver fir (Abies alba Mill.) water stress in its south-western distribution limit Google Scholar Google Scholar “Abies alba in Europe: distribution usage and threats,” in European Atlas of Forest Tree Species (Brussels: Publication Office of the European Union) Google Scholar PC-ORD Multivariate Analysis of Ecological Data Google Scholar Mechanisms of plant survival and mortality during drought: why do some plants survive while others succumb to drought An evaluation of relative robustness of techniques for ecological ordinations Google Scholar Sanasilva Tree Crown Photos with Percentages of Foliage Loss Google Scholar Radial-growth averaging criteria for reconstructing disturbance histories from presettlement-origin oaks doi: 10.1890/0012-9615(1997)067[0225:rgacfr]2.0.co;2 CrossRef Full Text | Google Scholar Decline of silver fir (Abies alba Mill.) stands in the Spanish Pyrenees: role of management CrossRef Full Text | Google Scholar Impacts of drought at different time scales on forest growth across a wide climatic gradient in north-eastern Spain Stand history: an alternative explanation of red spruce radial growth reduction CrossRef Full Text | Google Scholar Ecological requirements of Abies alba in the French Alps derived from dendro-ecological analysis Sánchez-Salguero Climate extremes and predicted warming threaten Mediterranean Holocene firs forests refugia Sánchez-Salguero Assessing forest vulnerability to climate warming using a process-based model of tree growth: bad prospects for rear-edges Sangüesa-Barreda drought and pathogens interact and contribute to forest dieback Spatiotemporal variability in tree ring growth in the Central Pyrenees: climatic and site influences doi: 10.1890/0012-9615(2003)073[0241:svitgi]2.0.co;2 The representative concentration pathways: an overview Vicente-Serrano A multiscalar drought index sensitive to global warming: the stamdardized precipitation evapotranspiration index Vicente-Serrano Evapotranspiration deficit controls net primary production and growth of silver fir: implications for Circum-Mediterranean forests under forecasted warmer and drier conditions Vicente-Serrano A high resolution dataset of drought indices for Spain “Los pirineos,” in La Vegetación de España Rivas-Martínez (Alcalá de Henares: Universidad De Alcala Servicio De Publicaciones) Google Scholar Note on the relation between ring widths and basal area increments Google Scholar What is the potential of silver fir to thrive under warmer and drier climate Characteristics of trees predisposed to die Google Scholar On the average value of correlated time series with applications in dendroclimatology and hydrometeorology doi: 10.1175/1520-0450(1984)023<0201:otavoc>2.0.co;2 Generalized Additive Models: An Introduction with R Google Scholar Sangüesa-Barreda G and Camarero JJ (2020) Forecasting Forest Vulnerability to Drought in Pyrenean Silver Fir Forests Showing Dieback Copyright © 2020 Gazol, Sangüesa-Barreda and Camarero. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) *Correspondence: J. Julio Camarero, ampjYW1hcmVyb0BpcGUuY3NpYy5lcw== Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher. 94% of researchers rate our articles as excellent or goodLearn more about the work of our research integrity team to safeguard the quality of each article we publish. Volume 10 - 2022 | https://doi.org/10.3389/fevo.2022.907492 This article is part of the Research TopicPast Interactions Between Climate, Land Use, and VegetationView all 22 articles The conifer tree species Norway spruce (Picea abies) silver fir (Abies alba) and Douglas fir (Pseudotsuga menziesii) are important elements in tree species composition and forest management of Central European forests but their potential to thrive under anticipated climatic changes is still debated controversially This study contributes a multivariate analysis of resilience components based on increment cores sampled at breast height of Norway spruce silver fir and Douglas fir trees growing along elevational gradients in Southwestern Germany We aimed to gain novel insights into the species-specific and elevational response of tree growth and wood density variables during the extreme drought events of the years 2003 and 2018 Our results for Norway spruce corroborate projections of its ongoing decline during climate change as the reductions of wood density and biomass production indicated high drought sensitivity at all elevations resilience indices of mean tree-ring density tree-ring width and biomass production were even lower after the drought of 2018 compared to the previous drought of 2003 a potential substitute tree species for Norway spruce showed unexpected results with resistance and resilience indices being significantly lower in 2018 compared to 2003 indicating that silver fir might be more vulnerable to drought than previously expected the superior growth rates and higher levels of drought tolerance of Douglas fir were especially pronounced during the drought of 2018 and visible across the entire elevational gradient even though high coning intensity was present for all investigated tree species as a possible confounding factor to exacerbate the drought stress effects in the study region Norway spruce shows lower drought tolerance than silver fir and Douglas fir Species-specific differences in drought responses are similar for both drought events Douglas fir shows superior growth rates and higher wood density compared to silver fir and Norway spruce Location of the study region in Southwestern Germany with the three established elevational transects in the Black Forest Sample size and mean values (with standard deviations in parentheses) of elevations tree age at breast height (t1.3) and slope for all sample trees grouped by species and elevational level Shaded areas represent the 2.5 and 97.5 % percentiles of annual deviations from the 30-year mean for the baseline climate period 1991-2020 All calculations and statistical data analyses were conducted in the R-programming environment (R Core Team, 2022) Besides the annual values of tree-ring width and maximum latewood density we also calculated for each tree-ring the mean tree-ring density (d¯) and estimated the annual stem radial biomass increment for the sampled increment cores using Equation 1: only the tree-rings of the years 2019 and 2020 were available as increment cores in the three replications were sampled before the growing season 2021 we included mean tree-ring density (d¯) maximum latewood density (mxd) and stem radial biomass increment (rbi) in a multivariate analysis of resilience components and calculated the drought tolerance indices resistance (Rt) recovery (Rc) and resilience (Rs) as follows: where Dr represents for the drought year j (2003 or 2018) the raw values of the measured variable k (trw, d¯, mxd or rbi) of tree i, whereas PreDr and PostDr denote the average values of the two pre-drought and two post-drought years, respectively. The raw data that were used to calculate the Lloret-indices for each variable are presented in Supplementary Figures 2–5 The drought tolerance indices were tested for significant differences between species using bootstrapped t-tests for unpaired samples with 10,000 replications with a Satterthwaite approximation to the degrees of freedom (Efron and Tibshirani, 1993; Kohl, 2020). Bootstrapped p-values were adjusted using the false discovery rate to account for multiple inference (Benjamini and Hochberg, 1995) The same statistical procedure was used when testing for significant differences of raw measurements between tree species during the pre-drought drought and post-drought years as the Lloret-indices only represent relative values and occlude different absolute growth levels To test for significant differences of the Lloret-indices between the drought years 2003 and 2018 bootstrapped t-tests for paired samples were used to account for non-independence of repeated measurements we calculated sample means with bias corrected and accelerated (bca) confidence intervals based on bootstrapping the sample mean 10,000 times To examine if drought tolerance indices of the investigated species varied with increasing elevation we subsetted the data on the tree species level and formulated linear mixed-effects models with random intercepts as follows: During the 2001–2005 period all tree species, and in particular Norway spruce, showed the highest intensity of coning in the post-drought year 2004. Douglas fir showed stronger coning intensity than silver fir and Norway spruce in the pre-drought year 2016. During the time period 2001-2020, the highest mean coning intensities were documented in the drought year 2018 for all investigated tree species (Supplementary Figure 6) In this chapter we present the species-specific drought tolerance indices in respect to the drought events of 2003 and 2018 All mentioned differences of the average values in the text below are significant between species and drought events (p < 0.05) recovery (E–H) and resilience (I–L) indices of mean tree-ring density tree-ring width and stem radial biomass increment of Norway spruce (PCAB) silver fir (ABAL) and Douglas fir (PSME) for the two extreme drought events of the years 2003 and 2018 Error bars indicate bootstrapped 95% confidence intervals of the sample means based on 10,000 replications Different lowercase letters above the error bars indicate significant differences between tree species within drought events Different uppercase letters above the error bars indicate for each species significant differences between both drought events (p < 0.05) This chapter describes the effects of elevation on the drought tolerance indices of the investigated species for the 2003 and 2018 drought events β1 coefficients) or differences in elevational trends between species were significantly different from zero based on bootstrapped 95% confidence intervals Silver fir and Douglas fir showed competitive levels of trw and rbi during the pre-drought growth levels of silver fir dropped much closer to Norway spruce This study presented a multivariate analysis of resilience components in respect to the extreme drought years 2003 and 2018 our results for Norway spruce corroborate projections of its ongoing decline during climate change as the reductions of wood density and biomass production indicated high drought sensitivity at all elevations showed unexpected results with resistance and resilience indices being significantly lower in 2018 compared to 2003 We conclude that silver fir might be more vulnerable to drought than previously expected Silver fir might also be increasingly susceptible to the effects of climate change if drought events coincide with fructification years and if post-drought years include periods of transient water stress as well Future research should explore the potentially non-linear growth responses of silver fir to the effects of temperature and water availability We speculate that the tipping point from positive to negative impacts of global warming on productivity of silver fir might be reached earlier than previously projected superiority in growth rates and growth resilience of Douglas fir was especially pronounced during the drought of 2018 The raw measurements used for data analysis can be made available by the authors upon reasonable request DS wrote the manuscript with support from TM DS conducted the measurements of tree-ring width and wood density DS performed the final data analysis with suggestions of H-PK This work was supported by the German Federal Ministry of Food and Agriculture and the German Federal Ministry for the Environment Nature Conservation and Nuclear Safety with grants: 22W-K-4-148 We acknowledge support by the Open Access Publication Fund of the University of Freiburg and Lea Kopp for technical support during field and laboratory work We are grateful to the local forest administration to facilitate our field work activities We also thank all reviewers of this manuscript for their helpful comments and valuable suggestions The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fevo.2022.907492/full#supplementary-material Rapid hydraulic collapse as cause of drought-induced mortality in conifers Compensatory mechanisms mitigate the effect of warming and drought on wood formation Barton, K. (2020). MuMIn: Multi-model inference. Available online at: https://CRAN.R-project.org/package=MuMIn (accessed July 18 Google Scholar Fitting linear mixed-effects models using lme4 CrossRef Full Text | Google Scholar Controlling the false discovery rate: A practical and powerful approach to multiple testing CrossRef Full Text | Google Scholar BMEL (2014). Dritte Bundeswaldinventur - Ergebnisdatenbank. Available online at: https://bwi.info/ (accessed February 23 Google Scholar Adaptive forest management in central Europe: Climate change impacts The influence of climate and management on survival probability for Germany’s most important tree species Growth responses to climate in a multi-species tree-ring network in the Western Carpathian Tatra Mountains Response of tree-ring density to climate in Maine Google Scholar Thinning increases drought tolerance of European beech: A case study on two forested slopes on opposite sides of a valley Temporal and spatial high-resolution climate data from 1961 to 2100 for the German National Forest Inventory (NFI) DWD (2022). DWD Climate Data Center (CDC): Grids of monthly averaged daily air temperature (2m), total precipitation, accumulated potential evapotranspiration over grass and soil moisture under grass and sandy loam over Germany. Available online at: https://opendata.dwd.de/climate_environment/CDC/grids_germany/monthly/ (accessed July 29 Google Scholar Google Scholar Tree-growth analyses to estimate tree species’ drought tolerance Impact of drought on the temporal dynamics of wood formation in Pinus sylvestris Drought and reproductive effort interact to control growth of a temperate broadleaved tree species (Fagus sylvatica) Mountain forest growth response to climate change in the Northern Limestone Alps CrossRef Full Text | Google Scholar “Technological properties of Douglas-fir wood,” in Douglas-fir: An option for Europe Schuler (Joensuu: European Forest Institute) Das Stammdickenwachstum von Buchen und Tannen in Baden-Württemberg unter dem Einfluss von Witterung und Klimaveränderungen – Langfristige Trends und kurzfristige Reaktionen auf Trockenheit Freiburg: Albert-Ludwigs-Universität Freiburg Google Scholar “Impact of the drought in 2003 on intra- and inter-annual stem radial growth of beech and spruce along an altitudinal gradient,” in TRACE - Tree rings in archaeology volume 4: Proceedings of the Dendrosymposium 2005 Schleser (Jülich: Forschungszentrum Jülich) PAST4 Q19 – Personal analysis system for tree ring research: Instruction manual Google Scholar Kohl, M. (2020). MKinfer: Inferential statistics. Available online at: http://www.stamats.de (Accessed February 23 Google Scholar “Management of douglas-fir,” in Douglas-fir: An option for Europe Google Scholar “Wachstum der Weißtanne in Südwestdeutschland: Entwicklung Klima-Risiko und Verjüngung,” in Wälder im klimawandel – Weißtanne und küstentanne Bayerische Landesanstalt für Wald und Forstwirtschaft (LWF) (Freising: Bayerische Landesanstalt für Wald und Forstwirtschaft) Google Scholar The geographical distribution of genetic variation of silver fir (Abies alba Pinaceae) in relation to its migration history CrossRef Full Text | Google Scholar A reassessment of carbon content in wood: Variation within and between 41 North American species CrossRef Full Text | Google Scholar Xylem phenology and growth response of European beech silver fir and Scots pine along an elevational gradient during the extreme drought year 2018 The 2018 hot drought pushed conifer wood formation to the limit of its plasticity: Consequences for woody biomass production and tree ring structure Substitution effects of wood-based products in climate change mitigation Google Scholar Components of tree resilience: Effects of successive low-growth episodes in old ponderosa pine forests CrossRef Full Text | Google Scholar Within-ring variability of wood structure and its relationship to drought sensitivity in Norway spruce trunks Ninety-five years of observed disturbance-based tree mortality modeled with climate-sensitive accelerated failure time models The wood density of surviving Douglas-firs to the 2003 drought and heat wave Freiburg: Forstliche Versuchs- und Forschungsanstalt Baden-Württemberg (FVA) Google Scholar Longer and faster: Intra-annual growth dynamics of Douglas fir outperform Norway spruce and silver fir over wide climatic gradients Five decades of growth in a genetic field trial of Douglas-fir reveal trade-offs between productivity and drought tolerance CrossRef Full Text | Google Scholar The summers 2003 and 2015 in South-West Germany: Heat waves and heat-related mortality in the context of climate change CrossRef Full Text | Google Scholar R Core Team (2022) R: A language and environment for statistical computing Google Scholar Wood density as a screening trait for drought sensitivity in Norway spruce Phenology of wood formation in larch (Larix decidua Mill.) trees growing along a 1000-m elevation gradient in the French Southern Alps San-Miguel-Ayanz Luxembourg: Publications Office of the European Union Google Scholar High-Frequency densitometry - a new method for the rapid evaluation of wood density variations CrossRef Full Text | Google Scholar Die Fichte: Ein handbuch in 2 bänden Google Scholar The past matters: Previous management strategies modulate current growth and drought responses of Norway spruce (Picea abies H A first assessment of the impact of the extreme 2018 summer drought on Central European forests Quantifying growth responses of trees to drought—a critique of commonly used resilience indices and recommendations for futures studies Impacts of fructification on biomass production and correlated genetic effects in Norway spruce (Picea abies [L.] Karst.) Google Scholar Cell structure in tree rings: Novel methods for preparation and image analysis of large cross sections Mean annual wood density variations of Larix gmelinii (Rupr.) Effects of intra-seasonal drought on kinetics of tracheid differentiation and seasonal growth dynamics of Norway spruce along an elevational gradient Responses of tree species to heat waves and extreme heat events Carbon content of tree tissues: A synthesis CrossRef Full Text | Google Scholar Zuwachstrend und Stressresilienz von Tanne und Fichte im Vergleich Google Scholar van der Maaten-Theunissen “Climate response of radial growth of silver fir (Abies alba Mill.) and Norway spruce (Picea abies (L.) Karst.) in the Black Forest Germany,” in TRACE - Tree rings in archaeology volume 10: Proceedings of the proceedings of the dendrosymposium 2011 van der Maaten-Theunissen Wood density variations of Norway spruce (Picea abies (L.) Karst.) under contrasting climate conditions in southwestern Germany Google Scholar van der Maaten-Theunissen Climate-growth relationships at different stem heights in silver fir and Norway spruce CrossRef Full Text | Google Scholar van der Maaten-Theunissen “History of introducing Douglas-fir to Europe,” in Douglas-fir: An option for Europe Vejpustková Climate response of Douglas fir reveals recently increased sensitivity to drought stress in Central Europe CrossRef Full Text | Google Scholar Seasonality matters—The effects of past and projected seasonal climate change on the growth of native and exotic conifer species in Central Europe Analysis of wood density profiles of tree stems: Incorporating vertical variations to optimize wood sampling strategies for density and biomass estimations Technical aspects of applying high frequency densitometry: Probe-sample contact sample surface preparation and integration width of different dielectric probes Exploring high frequency densitometry calibration functions for different tree species Seifert T and Kahle H-P (2022) Multivariate drought stress response of Norway spruce silver fir and Douglas fir along elevational gradients in Southwestern Germany Copyright © 2022 Stangler, Miller, Honer, Larysch, Puhlmann, Seifert and Kahle. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) *Correspondence: Dominik Florian Stangler, ZG9taW5pay5zdGFuZ2xlckB3d2QudW5pLWZyZWlidXJnLmRl Volume 10 - 2019 | https://doi.org/10.3389/fpls.2019.00214 This article is part of the Research TopicForest Genetic Monitoring - Preventing Forests Loss in a Changing ClimateView all 5 articles Root-associated fungal communities are important components in ecosystem processes impacting plant growth and vigor by influencing the quality and flow of nutrients and water between plants and fungi Linkages of plant phenological characteristics with belowground root-associated fungal communities have rarely been investigated and thus our aim was to search for an interplay between contrasting phenology of host ectomycorrhizal trees from the same location and root-associated fungal communities (ectomycorrhizal saprotrophic and pathogenic root-associated fungi) in young and in adult silver fir trees The study was performed in a managed silver fir forest site Twenty-four soil samples collected under two phenologically contrasting silver fir groups were analyzed for differences in root-associated fungal communities using Illumina sequencing of a total root-associated fungal community Significant differences in beta diversity and in mean alpha diversity were confirmed for overall community of ectomycorrhizal root-associated fungi whereas for ecologically different non-ectomycorrhizal root-associated fungal communities the differences were significant only for beta diversity and not for mean alpha diversity At genus level root-associated fungal communities differed significantly between early and late flushing young and adult silver fir trees We discuss the interactions through which the phenology of host plants either drives or is driven by the root-associated fungal communities in conditions of a sustainably co-naturally managed silver fir forest As processes in host and ECM fungi phenology need further clarification we are going to anticipate the relations in our study solely as an interplay between the host tree phenology and age and the root-associated fungal community we describe the community composition structure of root-associated fungi in a silver-fir dominated forest (2) tree age and (3) a combination of phenology and tree age We hypothesize that ECM and other root-associated fungal species richness (alpha diversity) differ based on phenological characteristics and tree age and is expected to be higher in association with adult and earlier flushing silver fir trees For adult stands it has been reported to be associated with more diverse and species richer fungal communities compared to young stands while for earlier flushing silver fir tree we expect to find higher fungal species richness due to earlier availability of photosynthates (Hypothesis 1) As plant and microbial processes vary throughout the season which has a strong impact on carbon and nitrogen availability we suspect that ECM and other non-ECM root-associated fungal community structure will have significantly different species turnover among trees with contrasting phenology and based on tree age (Hypothesis 2) and that consequently we will observe a significant difference in ECM and other non-ECM root-associated fungal genera abundances among the four analyzed groups roots were homogenized into a fine powder using a Retsch mixer mill (Retsch DNA was extracted from 50 mg of individual soil sample root powder using Reagent DNeasy Plant Mini Kit (Qiagen, Hilden, Germany) following manufacturer’s instructions. Additional DNA purification was done with Geneclean Turbo Kit (MP Biomedicals, Solon, OH, United States). Twenty-four differentially barcoded gITS7 forward primer and ITS4 reverse primer (Ihrmark et al., 2012) were used to amplify the ITS2 region of fungal ribosomal DNA PCR mix contained 2.5 μl 10× polymerase buffer 0.5 μl of PCR Nucleotide Mix (10 mM) 0.75 μl of polymerase (2 U μl−1; Pfu DNA polymerase: Dynazyme DNA polymerase PCRs were carried out in three replicates per sample using the following thermocycling conditions: initial 5 min at 94°C followed by 30 cycles at 94°C for 30 s 72°C for 30 s and final cycle of 7 min at 72°C each PCR product was run on 1% agarose gel Triplicates from the same root sample were then merged and purified with MinElute PCR Purification Kit (Qiagen the DNA concentration was determined by Qubit 2.0 United States) and equimolar concentrations were sequenced on Ilumina MiSeq (300 bp paired end) We used the most commonly used diversity indices: OTU richness which calculates the proportional abundance of each species and is interpreted as equivalent to OTU evenness which calculates the proportional abundance of the most abundant species and can be interpreted as OTU dominance Observed differences in fungal community composition between sites (beta diversity) were quantified with a pairwise permutational multivariate analysis of variance (pairwise PERMANOVA) based on the Bray-Curtis distance matrix Differences in overall fungal community composition were visualized using non-metric multidimensional scaling analysis (NMDS) ordinations using the Bray-Curtis distance matrix One-way ANOVA with Tukey contrasts was used to examine the difference in alpha diversity among the four groups (adult late and early flushing trees and young late and early flushing trees) The homogeneity of variance assumptions was checked with a Levene test (P = 0.102) Multivariate generalized linear models (MV-GLMs; Wang et al., 2012) were used to examine the differences in ECM and endophytic saprophytic and pathogenic genera abundances between phenologically different adult and young silver fir trees Multivariate and unadjusted univariate P-values were obtained by Wald tests both using 10,000 Monte Carlo permutations saprotrophic and pathogenic fungal genera with abundance higher than 1% were included in the plot The overall analysis was based on a total of 367,294 fungal ITS2 sequences that remained after the removal of non-fungal sequences and unclassified sequences at a kingdom or family level and length trimming following the Illumina MiSeq sequencing The overall dataset was divided into ECM OTUs and endophytic saprotrophic and pathogenic root-associated fungal OTUs The NMDS showed significantly different ECM communities between early and late flushing young trees (PERMANOVA, P = 0.003), while ECM communities of adult silver trees partially overlapped, with no significant differences between early and late flushing trees (PERMANOVA, P = 0.991) (Figure 1) Ectomycorrhizal (ECM) fungal community ordination plot based on communities from early/late flushing and adult/young silver fir trees calculated on a Bray-Curtis distance with a non-metric multidimensional scaling analysis (NMDS) ordination Presented are centroids of each groups of samples The ECM community significantly differs between early and late flushing young silver fir trees (PERMANOVA but not between early and late flushing adult silver fir trees (PERMANOVA Also, in the case of ecologically different non-ECM root fungal communities (Figure 2) NMDS showed significantly different endophytic (PERMANOVA P = 0.004) and pathogenic root fungal communities (PERMANOVA P = 0.004) between early and late flushing young silver fir trees while all three groups of non-ECM fungal communities of adult silver fir trees overlapped with no significant differences between early and late flushing trees (PERMANOVA endophytes saprotrophic (B) and pathogenic (C) fungal community ordination plots based on communities from early/late flushing and adult/young silver fir trees (A) Endophytic fungal community significantly differs between early and late flushing young silver fir trees (PERMANOVA (B) The saprotrophic fungal community also significantly differed between early and late flushing young silver fir trees (PERMANOVA (C) The same was revealed for the pathogenic fungal community which significantly differed between early and late flushing young silver firs (PERMANOVA Alpha diversity results coincide with differences in ECM observed in NMDS plots and supported with PERMANOVA. One-way ANOVA with Tukey contrasts conducted on mean alpha diversity among four groups of samples revealed significantly higher ECM fungal richness (Figure 3) in late flushing young silver fir trees compared to earlier flushing young trees (ANOVA whereas for ECM fungal richness of adult silver fir trees only the influence of interaction between phenology and age was observed We did not observe significant differences in mean evenness in ECM communities (ANOVA whereas the ECM community sampled from late flushing young silver fir trees showed significantly less dominance compared to late flushing adult silver fir trees (ANOVA Figure 3. Mean alpha diversity with +/- standard deviation of root-associated fungi as displayed as richness, evenness and dominance (Hill, 1973) of ectomycorrhizal (ECM) fungi based on community analyses from early/late flushing and young/adult trees There is a significant difference in OTU richness between early and late flushing young silver fir trees (ANOVA P = 0.033) and in dominance of the ECM fungal community between late flushing young silver fir trees and late flushing adult trees (ANOVA Different letters mark significantly different results (Tukey HSD test There was no significant difference (P > 0.106) in mean alpha diversity of the endophytic saprotrophic or pathogenic root-associated fungal community Among the 3,753 ECM fungal OTUs found in 24 root samples 2772 (73.8%) were identified to genus and 2150 (57.2%) to species level Among the 1681 non-ECM root-associated fungal OTUs found 1316 (78.2%) were identified to genus and 706 (41.9%) to species the most abundant ECM fungi were assigned to genera Russula endophytic fungi assigned to genera Meliniomyces Oidiodendron Phialocephala and saprophytic fungi Luellia were among the most abundant root-associated fungi and represented 27.5% of all sequences For adult silver fir trees, MV-GLM showed significant more abundant (Supplementary Table S1) ECM fungal genera Amanita, Cenococcum, Clavulina, Lactifluus, Sebacina and unclassified genera assigned to the order Entolomataceae (MV-GLM, P < 0.037) with early flushing adult silver fir trees compared to late flushing adult trees (Figure 4) we observed significantly more abundant ECM genera Amphinema Elaphomyces and unclassified genera assigned to Tricholomataceae (MV-GLM P < 0.037) with early flushing silver fir trees P < 0.011) which were significantly more abundant in association with late flushing silver fir trees Figure 4. Abundances of individual ectomycorrhizal (ECM) fungal genera on silver fir in relation to phenology and age. Different signs mark significantly higher genera abundances between early and late flushing trees separately for adult and young silver fir trees (Multivariate generalized linear models, ∗∗∗P < 0.001; ∗∗P < 0.01; ∗P < 0.05). For all genera abundances results, see Supplementary Table S1 In the case of non-ECM root-associated fungal genera (Figure 5) associated with adult silver fir trees, MV-GLM showed significant differences in abundances of endophytic fungal genera, namely Cryptosporiopsis, Oidiodendron, Phialocephala and of unclassified genera from the order Helotiaceae (MV-GLM, P < 0.049) (Supplementary Table S1) MV-GLM revealed significant differences in endophytic root-associated fungal genera Oidiodendron and the saprophytic root-associated fungal genus Luellia and in unclassified genera assigned to Myxontrichaceae whose abundance was higher in early flushing young trees the endophytic genus Meliniomyces and unclassified genera from endophytic Helotiaceae and saprotrophic Hyaloscyphaceae (MV-GLM P < 0.043) were significantly more abundant in association with late flushing silver fir trees Root-associated fungi assigned to unclassified Venturiaceae were the only pathogenic fungi with abundance higher than 1% and with significant differences between early and late flushing young silver fir trees (MV-GLM whereas we found no significant difference in mean alpha diversity of the endophytic saprophytic and pathogenic root-associated fungal community although some significant differences in abundances of ECM genera have been observed early and late flushing adult trees still show similar overall ECM community structure with no significant community composition turnover Yet their exact role in framing the plant partner phenology remains unexplored The significant interplay between the host tree phenology and root-associated fungal community was confirmed for young silver fir trees All four analyzed groups of root-associated fungal communities significantly differed between early and late flushing young silver fir trees as there was no significant difference in root-associated communities of phenologically contrasting adult silver fir trees There was also no significant difference in root-associated fungal communities between adult and young silver fir trees in general Mean alpha diversity analysis confirmed significant difference in fungal richness and dominance only for the ECM fungal community of silver fir trees whereas there was no significant difference in mean alpha diversity for the other three groups of non-ECM root-associated fungal communities saprophytic and pathogenic fungal genera between phenologically contrasting adult and young silver fir trees were confirmed which is in line with previously cited results This study is one of the few in which root-associated fungal communities are linked to the host tree phenology which gave us interesting results and an insight into the possible effect of root-associated fungi on host phenology and vice versa since a significant interplay between root-associated fungal communities and phenologically contrasting host trees was confirmed The analyzed dataset for this study can be found in the MG-RAST public database, under ID number mgm4821901.3 (Link: https://www.mg-rast.org/linkin.cgi?metagenome=mgm4821901.3) performed the NGS with the assistance of TM contributed to site selection and site parameters assessed by DF and performed the statistical analysis with the contribution of NŠ The study was funded by the Young Researcher Scheme (Slovenian Research Agency) and co-financed by The Research Programme P4-0107 Forest Biology and Technology (Slovenian Research Agency) The LIFEGENMON project (LIFE ENV/SI/000148) and a Short-Term Scientific Mission (STSM) granted by COST action FP1305 (BioLink) The authors acknowledge help in fieldwork from Miran Praznik (Slovenia Forest Service Regional Unit Maribor) and lab assistance from Barbara Štupar and Melita Hrenko (SFI) Reviewers are acknowledged for their contribution to improvement of the manuscript in the revision process The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fpls.2019.00214/full#supplementary-material Schwäbisch Gmünd: Einhorn-Verlag Google Scholar Clavulina-Membranomyces is the most important lineage within the highly diverse ectomycorrhizal fungal community of Abies religiosa Aronesty, E. (2011). ea-utils: Command-Line Tools for Processing Biological Sequencing Data. Available from: https://github.com/ExpressionAnalysis/ea-utils Google Scholar Mycorrhizal colonization of Pinus muricata from resistant propagules after a stand- replacing fire Evaluation of the internal colonization of Atriplex canescens (Pursh) Nutt Roots by dark septate fungi and the influence of host physiological activity Google Scholar ITSx: improved software detection and extraction of ITS1 and ITS2 from ribosomal ITS sequences of fungi and other eukaryotes for use in environmental sequencing Mycorrhizal and saprotrophic fungal guild compete for the same organic substrates but affect decomposition differently Root morphology and mycorrhizal symbiosis together shape nutrient foraging strategies of temperate trees Carbon sequestration is related to mycorrhizal fungal community shifts during long-term succession in boreal forests Fungi in ectomycorrhizal associations of silver fir (Abies alba Miller) in Central Italy CrossRef Full Text | Google Scholar The role of ectomycorrhizal communities in forest ecosystem processes: new perspectives and emerging concepts Stand age effects on boreal forest physiology using a long time-series of satellite data CrossRef Full Text | Google Scholar human-pathogenic species in the Herpotrichiellaceae are phenotypically similar to saprobic or phytopathogenic species in the Venturiaceae UPARSE: highly accurate OTU sequences from microbial amplicon reads Is forest mushroom productivity driven by tree growth Fernandez-Toiran Stand age and sampling year effect on the fungal fruit body community in Pinus pinaster forests in central Spain CrossRef Full Text | Google Scholar Études sur les mycorrhizas endotrophes Google Scholar Systematics of the genus Sphaerobolus based on molecular and morphological data with the description of Sphaerobolus ingoldii sp Gianinazzi-Pearson Recognition and Compatibility in Mycorrhizae,” in Genes Involved in Microbe-Plant Interactions Plant Gene Research (Basic Knowledge and Application) Google Scholar Regulation of mycorrhizal infection by hormonal factors produced by hosts and fungi CrossRef Full Text | Google Scholar a new anamorph genus for root-associated fungi with phylogenetic affinities to Rhizoscyphus ericae ( = Hymenoscyphus ericae) Diversity and evenness: a unifying notation and its consequences CrossRef Full Text | Google Scholar Endophytes – characteristics and possibilities of application in forest management CrossRef Full Text | Google Scholar Host phenology and potential saprotrophism of ectomycorrhizal fungi in boreal forests CrossRef Full Text | Google Scholar Below-ground-above-ground plant-microbial interactions: focusing on soybean New primers to amplify the fungal ITS2 region – evaluation by 454-sequencing of artificial and natural communities Dark septate endophytes – are they mycorrhizal CrossRef Full Text | Google Scholar Mycorrhizal functioning of Phialocephala fortinii with Pinus contorta on glacier forefront soil: interactions with soil nitrogen and organic matter Dark septate endophytes: a review of facultative biotrophic root-colonizing fungi CrossRef Full Text | Google Scholar Belowground carbon allocation by trees drives seasonal patterns of extracellular enzyme activities by altering microbial community composition in a beech forest soil “Multiple alignment of DNA sequences with MAFFT,” in Bioinformatics for DNA Sequence Analysis Host associations between fungal root endophytes and boreal trees Towards unified paradigm for sequence-based identification of fungi Ectomycorrhizal community structure varies among Norway spruce (Picea abies) clones Types of ectomycorrhizae – their taxonomy Google Scholar Cytokinin production by two ectomycorrhizal fungi in liquid culture CrossRef Full Text | Google Scholar “Ozone stress and ectomycorrhizal root-shoot signaling,” in Mycorrhiza Google Scholar - Shift in fungal communities and associated enzyme activities along an age gradient of managed Pinus sylvestris stands Successions of sheathing mycorrhizal fungi pigment chemistry and ecology in Hygrophoraceae (Agaricales) Lukešova The potential of dark septate endophytes to form root symbioses with ectomycorrhizal and ericoid mycorrhizal middle European forest plants Seeking the elusive function of the root-colonising dark septate endophytic fungi CrossRef Full Text | Google Scholar is a beneficial associate of the grass Vulpia ciliata spp CrossRef Full Text | Google Scholar Oksanen, J. F., Blanchet, G., Friendly, M., Kindt, R., Legendre, P., McGlinn, D., et al. (2018). vegan: Community Ecology Package. R Package Version 2.4-6. Available at: https://CRAN.R-project.org/package=vegan Google Scholar Girdling affects ectomycorrhizal fungal (EMF) diversity and reveals functional differences in EMF community composition in a beech forest Above- and below-ground community structure of ectomycorrhizal fungi in three Norway spruce (Picea abies) stands in Switzerland emergent properties: endophytes and microbiomes From genus to phylum: large-subunit and internal transcribed spacer rRNA operon regions show similar classification accuracies influenced by database composition R Core Team (2016) R: A Language and Environment for Statistical Computing Vienna: R Foundation for Statistical Computing Google Scholar Ectomycorrhizal fungal diversity: separating the wheat from the chaff Google Scholar VSEARCH: a versatile open source tool for metagenomics Ectomycorrhizal fungal assemblages of Abies alba Mill A thirty-year survey reveals that ecosystem function of fungi predicts phenology of mushroom fruiting Cryptic species and host specificity in the ectomycorrhizal genus Strobilomyces (Strobilomycetaceae) CrossRef Full Text | Google Scholar New species and records of saprophytic ascomycetes (Myxotrichaceae) from decaying logs in the boreal forest CrossRef Full Text | Google Scholar The foundational role of mycorrhizal networks in self-organization of interior Douglas-fir forests CrossRef Full Text | Google Scholar and composition of hypogeous and epigeous ectomycorrhizal fungal sporocarps in young and old-growth stands of Douglas-fir (Pseudotsuga menziesii) in the cascade range of oregon Physiological interactions between symbionts in vesicular-arbuscular mycorrhizal plants CrossRef Full Text | Google Scholar Google Scholar Community structure of ectomycorrhizal fungi in a Pinus muricata forest: minimal overlap between the mature forest and resistant propagule communities Ectomycorrhizal lifestyle in fungi: global diversity Community composition of root-associated fungi in a quercus-dominated temperate forests: “codominance” of mycorrhizal and root-endophytic fungi Ectomycorrhizal fungal succession in mixed temperate forests van der Heijden Mycorrhizal ecology and evolution: the pas The composition of arbuscular mycorrhizal fungal communities differs among the roots spores and extraradical mycelia associated with five mediterranean plant species Using Next-Generation Sequencing (NGS) to uncover diversity of wood-decaying fungi in neotropical Atlantic forests Větrovský Analysis of soil fungal communities by amplicon pyrosequencing: current approaches to data analysis and the introduction of the pipeline SEED Voriškova Fungal community on decomposing leaf litter undergoes rapid successional changes Diverse helotiales associated with the roots of three species of artic ericaceae provide no evidence for host specificity Production of ectomycorrhizal mycelium peaks during canopy closure in Norway spruce forests mvabund –An R package for model-based analysis of multivariate abundance data CrossRef Full Text | Google Scholar Ecological linkages between aboveground and belowground biota Ectomycorrhizal communities associated with silver fir seedlings (Abies alba Mill.) differ largely in mature silver fir stands and in scots pine forecrops CrossRef Full Text | Google Scholar Ectomycorrhizal fungal communities of silver-fir seedlings regenerating in fir stands and larch forecrops CrossRef Full Text | Google Scholar ggplot2: Elegant Graphics for Data Analysis CrossRef Full Text | Google Scholar Železnik CASIROZ: root parameters and types of ectomycorrhiza of young beech plants exposed to different ozone and light regimes Železnik Fine root dynamics in slovenian beech forests in relation to soil temperature and water availability Grebenc T and Kraigher H (2019) Root-Associated Fungal Communities From Two Phenologically Contrasting Silver Fir (Abies alba Mill.) Groups of Trees Copyright © 2019 Unuk, Martinović, Finžgar, Šibanc, Grebenc and Kraigher. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) *Correspondence: Tina Unuk, dGluYS51bnVrQGdvemRpcy5zaQ== Learn the subtle differences between Douglas Steve Nix is a member of the Society of American Foresters and a former forest resources analyst for the state of Alabama sf-dvs / Flickr / CC BY 2.0 Matt Lavin / Flickr / CC BY-SA 2.0 USDA Natural Resources Conservation Service / Wikimedia Commons / CC BY 2.0 Firs and spruces have many similarities and are often confused with each other but firs have needles that are rounded at the tip and flattened Spruce needles are sharp at the tip and square so that they roll easily between your fingers Fir trees can be identified by their soft and flattened needles usually green to dark green in color and rounded at the tip and disintegrate before falling to the ground If you spot what you think is a fir with intact cones on the ground "Balsam Fir." Arboretum "Pacific Silver Fir." Northwest Conifers "California Red Fir." American Conifer Society "Noble Fir (Abies procera)." Washington State Department of Natural Resources "Grand fir." Government of British Columbia "Fraser Fir." National Christmas Tree Association "Conifers - Douglas Fir." United States Forest Service "Douglas fir." Northwest Conifers. Volume 14 - 2023 | https://doi.org/10.3389/fmicb.2023.1246874 Forests are increasingly threatened by climate change and the Anthropocene seems to have favored the emergence and adaptation of pathogens Robust monitoring methods are required to prevent biodiversity and ecosystems losses and this imposes the choice of bioindicators of habitat health Fungal communities are increasingly recognized as fundamental components in nearly all natural and artificial environments and their ecosystem services have a huge impact in maintaining and restoring the functionality of ecosystems We coupled metabarcoding and soil analyses to infer the dynamics of a fungal community inhabiting the old silver fir stand in Vallombrosa (Italy) which is known to be afflicted by both Armillaria and Annosum root rot by a windstorm which caused a partial falling and uprooting of trees was used as a comparison to infer the consequences of the ecosystem disturbance We demonstrated that the abundance of pathogens alone is not able to explain the soil fungal differences shown by the two areas The fungal community as a whole was equally rich in the two areas even if a reduction of the core ectomycorrhizal mycobiome was observed in the wind-damaged area accompanied by the increase of wood saprotrophs and arbuscular mycorrhizas We hypothesize a reshaping of the fungal community and a potentially ongoing re-generation of its functionalities Our hypothesis is driven by the evidence that key symbiotic and saprotrophic guilds are still present and diversified in the wind-damaged area and that dominance of single taxa or biodiversity loss was not observed from a mycological point of view we aim at providing evidence that fungal communities are fundamental for the monitoring and the conservation of threatened forest ecosystems The forest of Vallombrosa, today a Biogenetic State Nature Reserve and a Natura 2000 Site, is also famous because the monks of the Vallombrosa Abbey (Benedictine order) in the XVII century began a centuries-old tradition, widespread to much of Central Europe, of growing pure and coetaneous silver fir (Abies alba Mill.) stand that still characterizes part of the forest landscape (Ciancio and Nocentini, 2011) that is now managed by the State body Carabinieri Forestali In order to assess the soil microbial community in the silver fir stand at ‘Metato’ (Natural Reserve of Vallombrosa and characterized by both presence of undamaged and wind-damaged areas (stumps) we profiled soil fungal communities by using metabarcoding and combined sequencing results with soil physico-chemical parameters The objectives of this work were the following: to investigate relations in the soil fungal community associated with A We hypothesize that an ecological succession has occurred since the windstorm event and hence that each condition is associated to a peculiar functional guild: for instance A alba undamaged trees associate with ectomycorrhizal fungi while stumps and the surrounding vegetation cover associate with Mortierellomycetes According to the pedological map of Tuscany Region the soil is mainly classified as partially humic dystrudepts Wind-damaged (A) and undamaged (B) areas at the “Metato” site The gaps in the forest caused by the windstorm allowed an increase of grasses and undergrowth the dense canopy cover in the undamaged area impedes this phenomenon Soil collection was carried out in two areas located at least 20 m apart from each other: one of 59,400 m2 characterized by undamaged trees and the other of 50,600 m2 by wind-damaged stumps Sampling was done under six silver fir trees and six stumps: five soil cores (200 cm3 each) of topsoil from underneath the litter layer were collected around two meters from each tree or stumps in opposite directions and at least two meters from each other to avoid sampling of the same genet Each biological replicate consisted in a pool of five soil samples (coarse roots and stones were removed) resulting in a composite soil sample for each tree composite soil (500–750 g; mesh size 1 mm) was used for physico-chemical analyses and another for microbial community analysis by metabarcoding Significant differences between undamaged and wind-damaged samples were determined with Kruskal-Wallis test in R at a 0.05 value of p threshold and manually curated by an expert mycologist the ratio between the abundance of each family and the abundances of all other taxa (relative abundance) was plotted Taxa with a relative abundance <0.01% or that were above this threshold in less than 60% of samples were discarded Statistical significance of core relative abundances between healthy and diseased samples was calculated with Kruskall-Wallis test (p < 0.05) Alpha- and beta-diversity values were computed with phyloseq and QIIME2 The correlation between the abundance of Armillaria and Heterobasidion pathogens and soil physico-chemical parameters was calculated with the base “cor” R function and plotted with ggplot2 The correlation threshold for the analysis was set to 70% this dominance was attenuated in soils sampled in the wind-damaged area where Mucoromycota showed quite high relative abundance Agaricomycota were the dominant class in both areas Mucoromycota were mostly represented by Mortierellomycetes in the undamaged area; by contrast Glomeromycetes and Endogonomycetes contributed to the increase in Mucoromycota observed in the wind-damaged area Ascomycota were well-represented in both sites with an even distribution of abundances in Dothideomycetes Physico-chemical characteristics of soils collected near the same stumps and undamaged trees that were selected for metabarcoding the density plots show the number of samples (represented by dots) having a specific value in the wind-damaged or undamaged area Statistical significance is shown in letters (Kruskall-Wallis test 0.05 threshold) Overall composition of the fungal community in Vallombrosa (A) Basidiomycota were predominant overall in terms of relative abundance (i.e. their abundance over the abundance of all OTUs) The classes Agaricomycetes (B) and Mortierellomycetes (C) were predominant in Basidiomycota and Mucoromycota while Ascomycota (D) had a more even class distribution and (D) represent samples and are distributed according to the relative abundances of each class (y axis) At the family-level, the core microbiome of the whole site was represented, after unknown families, by Mortierellaceae (with at least 50% relative abundance in 10% of the samples) followed by families such as Cortinariaceae (mostly ectomychorrhizal), Russulaceae, and Hydnaceae (Mycorrhizal; Figure 4A). This core community was overall less represented in soil samples from the wind-damaged area (Figure 4B) (A) Core community composition in terms of predominance the fraction of samples (1 = all samples and 0 = no sample) in which a specific family had at least the relative abundance defined on the x axis Mortierellaceae were present at 3% relative abundance in all samples we divided the abundances of OTUs representing the core mycobiome by the abundance of all OTUs (relative abundance) The core fungal community was more abundant in the undamaged area (Kruskall-Wallis test at p < 0.05) we decided to use this index for further analyses even if it introduces an evolutionary point of view that does not fit the present investigation The color codes represent undamaged (a) vs wind-damaged (ad) samples and are placed on the vertical axis based on their alpha diversity values according to each index Significance values were calculated with ANOVA To further investigate the impact of fall of the trees on the alpha diversity of specific functional guilds, we measured the same alpha diversity indices on the ectomycorrhizal and wood-decay communities separately (Supplementary Figures S2, S3) Faith’s PD was higher for the wood-decay community in the wind-damaged area; by contrast all alpha diversity indices indicated a strong reduction of the ectomycorrhizal diversity as a consequence of fall of the trees To further highlight compositional differences of the mycobiota between soils sampled in the wind-damaged and undamaged area, we used both unweighted (phylogeny-based) and weighted (which further adds abundance data to the phylogeny-based method) UniFrac indices (Lozupone and Knight, 2005). In both cases beta diversity revealed a clear separation between soils from the wind-damaged area vs those sampled in the undamaged area (Figure 6) The color and shapes of the dots represent undamaged vs and both weighted and unweighted UniFrac indices were calculated The size of each dot (sample) is related to the Faith’s PD of that sample Both indices highlight a separation of the two areas in terms of mycobiota composition Differential abundance tree showing differentially-abundant Basidiomycota in the wind-damaged vs undamaged areas Red color for nodes and edges indicates over-representation in the wind-damaged condition The color intensities were calculated by summing all log2 fold changes of OTUs gathered at each node and branch We found no correlation between soil parameters and the abundance of Armillaria or Heterobasidion: it is possible that these potential abiotic stressors may have a negative impact on tree fitness and ectomycorrhizal communities it is likely that parameters such as C/N ratio and mineral content are directly influenced by the increased amount of dead plant material accumulated after the falling of the trees the ectomycorrhizal community is still detectable in the wind-damaged area and specific genera are core components of the “Metato” mycobiome Ectomycorrhizal Ascomycota were also present but were relatively less abundant in the investigated soils this diversity and specificity may lead to the hypothesis that an ectomycorrhizal succession is supporting habitat restoration in Vallombrosa Ectomycorrhizal fungi have different hyphal exploration types that vary from long-range to contact-range thanks to a long-range hyphal exploration type they maintain symbiotic associations with living trees in the undamaged area while extending their mycelial network in the proximity of fallen trees pointing out to different fundamental environmental services the plant succession in the wind-damaged area could stimulate a parallel microbial succession with rapid replacement of taxa with increasing adaptability to the rhizosphere Future development of this approach would arguably require monitoring of the fungal community over time which would help to identify when adverse conditions take place and which actors are at play before and after a disturbance The data presented in the study are deposited in the NCBI database GDR: conceptualization and funding acquisition The research was founded thanks to the EU LIFE program in the framework of the LIFE MycoRestore project (LIFE18/CCA/ES/001110) The authors want to thank the coordinator of the LIFE project the technicians Vincenzo Di Lonardo and Stefano Secci for helping in the field work Sara Di Lonardo and Luigi D’Aqui at IRET–CNR for soil analysis for the various essential support to the project and to the research the Carabinieri Biodiversity Group The Supplementary material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fmicb.2023.1246874/full#supplementary-material Allmér Wood-inhabiting fungal communities in woody debris of Norway spruce (Picea abies (L.) karst.) as reflected by sporocarps mycelial isolations and T-RFLP identification Google Scholar Forest tree growth is linked to mycorrhizal fungal composition and function across Europe Efficient computation of Faith’s phylogenetic diversity with applications in characterizing Ectomycorrhizal networks in the Anthropocene: from natural ecosystems to urban planning scalable and extensible microbiome data science using QIIME 2 CrossRef Full Text | Google Scholar DADA2: high-resolution sample inference from Illumina amplicon data Google Scholar Phylogenomics of Endogonaceae and evolution of mycorrhizas within Mucoromycota Google Scholar CrossRef Full Text | Google Scholar MUSCLE: multiple sequence alignment with high accuracy and high throughput PubMed Abstract | CrossRef Full Text | Google Scholar Google Scholar Metacoder: an R package for visualization and manipulation of community taxonomic diversity data CrossRef Full Text | Google Scholar CrossRef Full Text | Google Scholar Evolution and adaptation of forest and crop pathogens in the Anthropocene Kalntremtziou Evaluation of the lignocellulose degradation potential of Mediterranean forests soil microbial communities through diversity and targeted functional metagenomics Google Scholar Google Scholar CrossRef Full Text | Google Scholar Google Scholar Moderated estimation of fold change and dispersion for RNA-seq data with DESeq2 UniFrac: a new phylogenetic method for comparing microbial communities CrossRef Full Text | Google Scholar Google Scholar Phyloseq: an R package for reproducible interactive analysis and graphics of microbiome census data Recent insights on biological and ecological aspects of ectomycorrhizal fungi and their interactions Sheltering role of well-decayed conifer logs for forest floor fungi in long-term polluted boreal forests Google Scholar Significant increase in natural disturbance impacts on European forests since 1950 CrossRef Full Text | Google Scholar FastTree 2–approximately maximum-likelihood trees for large alignments CrossRef Full Text | Google Scholar Pulido-Chavez Rapid bacterial and fungal successional dynamics in first year after chaparral wildfire Google Scholar CrossRef Full Text | Google Scholar Ruiz Gómez Assessment of functional and structural changes of soil fungal and oomycete communities in holm oak declined dehesas through metabarcoding analysis CrossRef Full Text | Google Scholar Intestinal microbiome landscaping: insight in community assemblage and implications for microbial modulation strategies CrossRef Full Text | Google Scholar Negative linear or unimodal: why forest soil fungal latitudinal diversity differs across China PubMed Abstract | CrossRef Full Text | Google Scholar and δ15N variations driven by tree roots CrossRef Full Text | Google Scholar CrossRef Full Text | Google Scholar Improvement of phylogenies after removing divergent and ambiguously aligned blocks from protein sequence alignments Plant–microbiome interactions: from community assembly to plant health CrossRef Full Text | Google Scholar Localized reshaping of the fungal community in response to a forest fungal pathogen reveals resilience of Mediterranean mycobiota Google Scholar CrossRef Full Text | Google Scholar CrossRef Full Text | Google Scholar Della Rocca G and Mello A (2023) Responses of a soil fungal community to severe windstorm damages in an old silver fir stand Received: 06 July 2023; Accepted: 25 September 2023; Published: 10 November 2023 Copyright © 2023 Venice, Vizzini, Danti, Della Rocca and Mello. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) *Correspondence: Antonietta Mello, YW50b25pZXR0YS5tZWxsb0BpcHNwLmNuci5pdA== Posted by Mary West | Oct 20, 2023 2:51 pm | Day Trips & Destinations I stumbled on Sawtooth Trail looking for some exercise during the lunch break of a day-long conference in Truckee It’s hard to sit in a meeting anywhere in the Sierra Nevada Mountains and not look out any window at the uplifted granite glacier sculpted terrain and want to be outside I went to the internet to find a near-by trail Sawtooth Trail was close and promised great views.  Plenty of parking welcomed me to the trailhead No toilets here but plenty of room to wander This is a popular mountain bike trail so be prepared to step aside and let them pass by.  I ventured out the dusty trail and enjoyed the tent caterpillars dancing on their tents the Paintbrush was blooming and butterflies accompanied me along the path so at 30 minutes I stopped at a rock outcropping overlooking the river and range around me I wish I had more time to explore but I had more to learn back inside.  According to the Truckee Trails Foundation website “This trail is a winding single-track loop through a mix of high desert and Jeffrey Pine Forest.  It gains and loses the same 200 feet numerous times throughout its course   Some of the standout features of this trail are the two overlooks into the Truckee River Canyon and the available connectivity to other routes on the Mt or mountain bike ride.  The total loop is 9 miles.” To get to Sawtooth Trail on the Tahoe National Forest in Placer County take the first exit and stay on Donner Pass Road Stay right onto 06 Fire Road to the trailhead at 11632 06 Fire Road At the trailhead I found a simple sentiment that seemed to resonate with my social media friends.  Mary West is author of the book series Day Hiker – Gold Country Trail Guide I II and III (2nd edition Available on Amazon) The books are a collection of the Day Hiker columns where West shares her longtime love of the outdoors favorite hikes in Northern California’s Gold Country and beyond West was the recipient of the 2017 and 2019 CRAFT Award for Best Outdoor Column and the 2020 Craft Award for her second book in the series-Day Hiker Gold Country Trail Guide by the Outdoor Writers of California You can follow West on Facebook and Instagram About UsPrivacy PolicyTerms and ConditionsContact UsSubscribe for FREE! Advertise with UsBusiness DirectorySubmit a Press ReleaseBecome a ContributorJobs Nominate your favorite Businesses TODAY! Copyright © 2023, All Town Media, LLC,  An American Owned Company. All rights reserved. The Best of Times is going on right now! Make sure you get those nominations in before voting begins. Photo courtesy of Dr. Andrew Larson, University of Montana Download the NPS app to navigate the parks on the go. Pacific Northwest, 53,400 mi2 (138,300 km2) Western hemlock and Sitka spruce in the Cascade Province, Olympic National Forest, Washington. Vegetation.--The Cascade Province is primarily montane, but it ranges from sea level to altitudes above 5,000 ft (1,500 m). At the lowest elevations, there is a dense conifer forest of Douglas-fir, western redcedar, western hemlock, grand fir, silver fir, Sitka spruce, and Alaska-cedar. Numerous species of shrubs grow exceptionally well in this forest and around its margins. In many places, this vegetation is practically impenetrable. Although Douglas-fir is the most abundant tree at lower elevations in the region, it is not part of the climax forest. Western hemlock and several other species of fir are more tolerant of shade than Douglas-fir, and in mature forest stands, Douglas-fir cannot regenerate. On the western and southern slopes of the Olympic Mountains in Washington, hemlock is eventually displaced by the more shade-tolerant silver fir. In the humid conifer forests of southwestern Oregon, Alaska-cedar is replaced by silver fir and redwood. In the fog belt along the coast of northwestern California, redwood is the characteristic tree. Douglas-fir and other conifers associate with it to form perhaps the densest of all coniferous forests, with the world's largest trees. Some redwoods attain heights of more than 325 ft (99 m) and girths of more than 65 ft (19.8 m). A xerophytic forest of ponderosa pine grows along the dry eastern slopes of the Cascades, descending to 500 ft (150 m) along the eastern foot of the range at the Columbia River. This is typically open forest mixed with grass and shrubs. It occurs throughout the Southwest, the Sierra Nevada, the Rocky Mountains, and the Black Hills. An open, parklike stand of ponderosa pine, Deschutes National Forest, Oregon. The high, snowcapped mountains of the Cascades have a well-marked subalpine forest belt that reaches into British Columbia. Important trees are mountain hemlock, subalpine fir, whitebark pine, and Alaska-cedar. To the north, the subalpine forest becomes fragmentary or disappears completely. All but the highest peaks are covered by forest. In the Cascade Mountains of Oregon, timberline varies from 7,700 to 10,000 ft (2,350 to 3,050 m). Above timberline, there is an alpine zone with rich communities of shrubs and herbs. Perpetual snow is confined to small patches. Riparian forests in the Pacific Northwest are an exception to the general rule that conifers dominate in the region. Along the region's many rivers and streams, needleleaf trees are replaced by broadleaf species such as black cottonwood and red alder. This kind of forest occurs from southern Alaska south through Washington, Oregon, Idaho, and western Montana, continuing into northern California and the Sierra Nevada. Soils.--Andisols are extensive where underlain by volcanic ash. Moist Inceptisols are found west of the Cascades; dry soils predominate in the rain shadow east of the mountains. Fauna.--Common large mammals include elk, deer, mountain lion, bobcat, and black bear. Small mammals include mice, Douglas squirrels, martens, Townsend chipmunks, red tree voles, and bushytail wood rats. The more common birds are the winter wren, Townsend's warbler, chestnut-backed chickadee, red-breasted nuthatch, gray jay, and Steller's jay. The most important game birds are blue and ruffed grouse; there are hawks and owls in the northwestern part of the province. Spotted owl and marbled murrelet depend on remaining old-growth forests. Among the many species of amphibians that live in this region's moist, cool forests are the Pacific treefrog and the Pacific giant salamander. Reptiles include the northern alligator lizard and rubber boa. The many swift-flowing rivers of the region are high in dissolved oxygen and generally unpolluted, making them ideal habitats for various salmon and trout species. Volume 15 - 2024 | https://doi.org/10.3389/fpls.2024.1380275 This article is part of the Research TopicCombined Abiotic Interactions in Woody PlantsView all 10 articles Predicting global change mitigations based on environmental variables although yielding insightful hypothesis still lacks the integration of environmental responses Physiological limits should be assessed to obtain a complete representation of a species’ fundamental niche Detailed ecophysiological studies on the response of trees along the latitudinal gradient are rare They could shed light on the behaviour under different light intensities and other studied traits The forests of the Dinaric Mountains and the Carpathians represent the largest contiguous forest complexes in south-eastern Europe In uneven-aged Carpathian (8 plots) and Dinaric Mountain (11 plots) forests net assimilation (Amax) and maximum quantum yield (Φ) were measured for beech and fir in three predefined light intensity categories according to the indirect site factor (ISF%) obtained by the analysis of hemispherical photographs in managed and old growth forests The measurements were carried out under fixed environmental conditions in each light category per plot for three consecutive years Data from the last 50-year average period from the CRU TS 4.01 dataset were used for the comparison between Amax The highest Φ for beech were observed in the central part of the Dinaric Mountains and in the south westernmost and northwesternmost part of the Carpathians for both beech and fir while they were highest for fir in the Dinaric Mountains in the northwesternmost part of the study area The Φ-value of beech decreased in both complexes with increasing mean annual temperature and was highest in the open landscape Φ decreased with increasing mean annual temperature while in the Dinaric Mountains it increased with higher temperature and showed a more scattered response compared to the Carpathians Short-term ecophysiological responses of beech and fir were consistent to long-term radial growth observations observed on same locations The results may provide a basis and an indication of the future response of two tree species in their biogeographical range to climate change in terms of competitiveness existence and consequently forest management decisions soil carbon and nitrogen content and no significant affect connected with canopy gaps Our aim was to compare the physiological responses of beech and fir along the geographical gradient of the Carpathian and Dinaric Mountains (1) to assess differences in the same light categories of both species between managed and old forests (2) and to verify the relationship between climatic parameters and ecophysiological traits of both species along both geographical gradients (3) The Carpathians extend over a 1500 km long arc, the width of which varies from 170 km in the eastern and western parts to less than 80 km in the southern part of the mountain range (Warszyńska, 1995). The wide variety of favourable ecological conditions is reflected in the great diversity of plants and animals and the rich biodiversity (Mirek and Piekos-Mirkowa, 1992) with several protected old-growth forest remnants scattered across the area Figure 1 Research area and location of the permanent research plots along the Carpathian and Dinaric Mountains The green dots represent old-growth reserves Table 1 Characteristics of the research plot; the meteorological data were obtained from the website “Climate Explorer” (http://climexp.knmi.nl) for the period 1985-2020 including the annual totals and the values for the April-September growing season Figure 2 Average seasonal air temperature and precipitation (April-Sept. Leaves were dried to constant weight at 105°C for 24 hours and weighed in the laboratory to determine leaf mass per area (LMA) [g/m2] For the light saturation measurements, which were carried out in June and July in three consecutive growing seasons, at least 8 young trees of the same height that were not obstructed by their neighbours were randomly selected (sensu Čater and Levanič (2019) The age of the trees varied between 5-12 years The light response was measured with a portable LI-6400 (Li-Cor USA) system on at least four leaves/shoots per tree located in the upper third of the tree crowns All assimilation values were recorded after they had held constant for 2 min or until the coefficient of variability (CV%) dropped below 5% • Light saturation curves were generated to compare net assimilation (Amax) in young beech and fir trees under the same light conditions All assimilation measurements were performed in the field at a constant temperature of the measurement block (200C) an air flow of 500 µmols-1 and different light intensities: 0 The maximum assimilation rates (Amax) for the light saturation curves were used to compare the responses between different light categories and plots • The characteristic points of maximum quantum yield (Φ), defined as the maximum amount of fixed CO2 per amount of absorbed light quanta (Lambers et al., 1998) measured as the initial slope of the light response curve of CO2 fixation, were determined for each light category, species and plot, as described in Čater et al. (2014) Differences between the same years for the LMA Amax and Φ were tested using two-way ANOVA with tree species (beech and fir) and light (open Analyses of variance (ANOVA) and the HSD Tuckey post-hoc test were performed after testing data to meet conditions of normality p<0.01 (**) and p<0.001 (***) were considered significant correlation between the measured variables and multiple regression were performed using Statistica Data Analysis Software System (2011) In both complexes, the long-term average temperatures show more homogeneous conditions over the longer Dinaric area and more variable conditions in Carpathians. The average annual precipitation in the Carpathian region is lower and corresponds to the conditions in the southern Dinaric mountains. (plot 9) (Figure 2) The values of Ntot and LMA were slightly and not significantly lower in all categories in the Carpathian Mountains than in the Dinaric Mountains (Figure 3, Table 2) Figure 3 Foliar nitrogen (Ntot) and leaf mass per area (LMA); bars are standard errors Table 2 ANOVA for leaf nitrogen (Ntot) and leaf mass per area (LMA) in both regions Figure 4 Average quantum yield (Φ) in all light categories The shaded areas represent old growth reserves Table 3 ANOVA for maximum assimilation rate (Amax) and quantum yield (Φ) for beech and fir in different light conditions and complexes The highest values (Φ) for beech were observed in the central part of the Dinaric Mountains region and in the south westernmost and northwesternmost part of the Carpathian Arc for both beech and fir, while Φ for fir was highest in the Dinaric Mountains in the northwesternmost part of the studied area (Figure 4) Post-hoc analyses revealed significant differences between all light categories for Φ in Dinaric Mountains, except in the old-growth reserves, where no significant differences between forest edge and open light were confirmed for either species. In Carpathian Mountains differences between light categories were not so pronounced (Table 4) Table 4 Post hoc (HSD) analysis for quantum yield (Φ) for beech and fir between C (canopy) We confirmed positive correlation between Φ and annual precipitation, which increased with the light intensity for beech in all light categories and in both the Carpathian and Dinaric Mountains. The correlation was positive for fir, decreased with increasing light and was highest when the canopy was closed. Slope of the curve for fir was steepest for the closed canopies (Figure 5) Figure 5 Quantum yield (Φ) as a function of precipitation and temperature The quantum yield of beech in both complexes decreased with increasing mean annual temperature and was highest in the open. For fir in the Carpathian Mountains, Φ decreased with increasing mean annual temperature, while in the Dinaric Mountains it increased with higher temperature and showed a more scattered response compared to the Carpathian Mountains (Figure 5) Figure 6 Multiple regression coefficients between independent (average annual air temperature - Ta altitude - Alt) and dependent quantum yield (Φ) variables for both species The selected sites in both studied mountain complexes were above 800m a.s.l. to ensure comparable and similar climatic conditions. Altitude is the key factor controlling the microclimate in temperate mountain forest stands (Körner et al., 2016) The average annual temperatures at the selected Carpathian sites ranged between 12 and 14 0C with the exception of sites 4 and 1 while the average annual temperatures at the Dinaric sites showed more homogeneous conditions (13 to 14 0C) The average amount of precipitation in the Dinaric Mountains decreased evenly from the north-west to south-east while the amount of precipitation in the Carpathians decreased from west to east Φ was highest for beech in the central area (Bosnia and Herzegovina) and for fir in the north-western part of the transect (Slovenia while in the Carpathians it was highest at the beginning and end of the studied transect The responses (Φ) of the two species studied between the Carpathians and the Dinaric Mountains in the same light categories showed certain similarities: in both cases, Φ values were higher for beech in the open, and lowest under shaded canopies, and vice versa for fir - highest under shaded conditions and lowest in the open, confirming our previous studies (Čater and Levanič, 2013, 2019) With increasing precipitation, Φ increased in both fir and beech in the Carpathian and Dinaric Mountains, especially in fir, where the slope and dependence on shading increased. The correlation between Φ and mean annual temperature was negative at all sites for beech and fir in the Carpathians, while in the Dinaric Mountains the correlation was reversed for fir (Figure 5) The main reason for the negative correlation between Φ and increasing mean temperature in all light categories for fir could be the lower precipitation in the Carpathians The value of the correlation coefficient of the multiple regression increased with increasing number of independent variables and Φ for the beech in the Carpathians, while it remained the same for the Dinaric Mountains, which could indicate that the independent variables influence the beech differently in both mountain complexes (Figure 6 showed a similar dependence on an increasing number of the same independent variables in both the Carpathians and the Dinaric Mountains Our study confirmed a better light utilisation of fir in the shade and a different relationship with increased average temperatures in combination with lower precipitation The lower Φ of fir utilisation of high-intensity solar radiation compared to beech could be a competitive disadvantage in large gaps in the canopy which could limit the recruitment of species in the understorey or in small gaps the quantum yield of beech and fir showed the lowest values in the eastern part and the highest values in the west four different groups were formed according to similar growth responses: two northern regions - A (including plots 1-4) and B (plot 5) and two southern regions - C (plots 6-8) and D (plots 9-11) The average Φ corresponded well to the growth response of the same group (A D) and was more pronounced for the longer latitudinal distance than for the Carpathian Arc which is similar in distance but shorter in latitudinal scale Studies also indicate a different response of the species along its distribution range. The radial growth of silver fir has increased significantly in Central Europe over the last 30 years, while it has decreased in drought-prone Mediterranean regions (Büntgen et al., 2014). Furthermore, different growth patterns have been observed between northern and southern populations of silver fir in Italy (Carrer et al., 2010) relatively short-term ecophysiological responses of beech and fir provided information on the behaviour at three different light intensity categories compared to long-term radial growth observations The efficiency of beech increased with light intensity in all light categories and in both mountain complexes while the response of fir was the opposite The main difference between the two larger areas was the response of young fir to increasing temperatures which correlated positively with increasing temperatures in the Dinarides and negatively in the Carpathians this difference is related to the high precipitation in the Dinaric Mountains and the low precipitation in the Carpathians Our results may give an indication of how two important tree species in their biogeographical range will react to climate change in the future No plants or animals (including human) were harmed during this study The author(s) declare that financial support was received for the research The authors acknowledge the financial support from the Slovenian Research Agency (research core funding P4-0107 Program research at the Slovenian Forestry Institute J4-3086 and by the Young Researcher program of the Slovenian Research Agency and by the Czech Science Foundation GAČR No Growth response of European beech (Fagus sylvatica L.) and Silver Fir (Abies alba Mill.) to climate factors along the Carpathian massive Alba-Sánchez Past and present potential distribution of the Iberian Abies species: a phytogeographic approach using fossil pollen data and species distribution models doi: 10.1111/j.1472-4642.2010.00636.x CrossRef Full Text | Google Scholar Light and VPD gradients drive foliar nitrogen partitioning and photosynthesis in the canopy of European beech and silver fir Karte der natürlichen Vegetation Europas/Map of the Natural Vegetation of Europe Google Scholar Effects of post-glacial phylogeny and genetic diversity on the growth variability and climate sensitivity of European silver fir Contrasting tree-ring growth to climate responses of Abies alba toward the southern limit of its distribution area doi: 10.1111/j.1600-0706.2010.18293.x CrossRef Full Text | Google Scholar spruce and sycamore to rapid light exposure after large-scale disturbance CrossRef Full Text | Google Scholar CrossRef Full Text | Google Scholar CrossRef Full Text | Google Scholar CrossRef Full Text | Google Scholar Beech and silver fir’s response along the Balkan’s latitudinal gradient PubMed Abstract | CrossRef Full Text | Google Scholar Čavlović Effects of canopy opening on height and diameter growth in naturally regenerated beech seedlings CrossRef Full Text | Google Scholar and soil properties on soil CO2 efflux in beech-fir forests along the Carpathian Mts CrossRef Full Text | Google Scholar Latitudinal gradients as natural laboratories to infer species’ responses to temperature doi: 10.1111/j.1365-3040.2010.02114.x Human-derived landscape changes on the northern Etruria coast (western Italy) between Roman times and the late Middle Ages CrossRef Full Text | Google Scholar Vegetation ecology of central Europe (Cambridge: Cambridge University Press) Google Scholar CrossRef Full Text | Google Scholar Some morphological characteristics of the dinaric karst Google Scholar Climate change projections for the Mediterranean region CrossRef Full Text | Google Scholar The north european platform suture zone in poland Google Scholar Updated high-resolution grids of monthly climatic observations–the CRU TS3 CrossRef Full Text | Google Scholar Long-term patterns in soil acidification due to pollution in forests of the Eastern Sudetes Mountains Untersuchungen zur natürlichen Verjüngung des Bergmischwaldes: erste Ergebnisse eines Forschungsprojekts in den ostbayerischen Kalkalpen Google Scholar Short-term impacts of harvesting intensity on the upper soil layers in high karst Dinaric fir-beech forests Automatic thresholding for digital hemispherical photography CrossRef Full Text | Google Scholar Tree spatial patterns of Abies alba and Fagus sylvatica in the Western Carpathians over 30 years Tree spatial patterns of Fagus sylvatica expansion over 37 years CrossRef Full Text | Google Scholar Explaining the low-temperature range limits of temperate tree species Das mikroklima der kieferlochkahlschläge: III Google Scholar Plant physiological ecology (NewYork: Springer) CrossRef Full Text | Google Scholar Physiological plant ecology: ecophysiology and stress physiology of functional groups (New York: Springer Science & Business Media) Google Scholar Methodology comparison for canopy structure parameters extraction from digital hemispherical photography in boreal forests Synthesis report of the IPCC Sixth Assessment Report (AR6) Google Scholar photosynthetic rates and chlorophyll fluorescence images of sun and shade leaves of four tree species Growth patterns and sensitivity to climate predict silver fir decline in the Spanish Pyrenees CrossRef Full Text | Google Scholar Forest harvesting effects on soil temperature and respiration in a bottomland hardwood forest doi: 10.2136/sssaj1999.03615995006300030029x A 13-year change in ground-layer vegetation of Carpathian beech forests Google Scholar Photographic exposure affects indirect estimation of leaf area in plantations of Eucalyptus globulus Labill doi: 10.1111/j.1466-8238.2012.00767.x Marinšek doi: 10.1111/j.1654-109X.2012.01203.x CrossRef Full Text | Google Scholar Mauri, A., De Rigo, D., Caudullo, G. (2016). Abies alba in Europe: distribution, habitat, usage and threats (Luxembourg: European Atlas of Forest Tree Species Publ. Off. EU). Available at: https://w3id.org/mtv/FISE-Comm/v01/e01493b Google Scholar Co-occurrence patterns of trees along macro-climatic gradients and their potential influence on the present and future distribution of Fagus sylvatica L Comparison of new foliar nutrient thresholds derived from van den Burg’s literature compilation with established central European references Google Scholar “Geomorphology,” in Introduction to dinaric karst Google Scholar Flora and vegetation of the polish tatra mountains CrossRef Full Text | Google Scholar The natural disturbance regime in forests of the Dinaric Mountains: A synthesis of evidence L’influence de divers caract??res architecturaux sur l’apparition de la fourche chez le Fagus sylvatica en fonction de l’absence ou de la pr??sence d’un couvert Automatic thresholding for hemispherical canopy-photographs based on edge detection CrossRef Full Text | Google Scholar CrossRef Full Text | Google Scholar Rădulescu The plate-tectonics concept and the geological structure of the carpathians CrossRef Full Text | Google Scholar CrossRef Full Text | Google Scholar Dynamics of windthrow events in a natural fir-beech forest in the Carpathian mountains CrossRef Full Text | Google Scholar Trends and cyclical changes in natural fir-beech forests at the north-western edge of the Carpathians CrossRef Full Text | Google Scholar CrossRef Full Text | Google Scholar CrossRef Full Text | Google Scholar Hemispheric image modeling and analysis techniques for solar radiation determination in forest ecosystems CrossRef Full Text | Google Scholar Ecophysiological adaptations shape distributions of closely related trees along a climatic moisture gradient CrossRef Full Text | Google Scholar Limited filling of the potential range in European tree species doi: 10.1111/j.1461-0248.2004.00614.x CrossRef Full Text | Google Scholar Vološčuk The national parks and biosphere reserves in carpathians: The last nature paradises (Tatranska Lomnica Slovak Republic: Association of the Carpathian National Parks and Biosphere Reserves) Google Scholar European beech (Fagus sylvatica L.) and silver fir (Abies alba Mill.) rotation in the Carpathians—A developmental cycle or a linear trend induced by man Warszyńska Poland: Jagiellonian University Publication) Google Scholar Branch xylem vascular adjustments in European beech in response to decreasing water availability across a precipitation gradient Syntaxonomische Revision der südmitteleuropäischen Buchenwälder Syntaxonomical revision of the beech forests of southern Central Europe doi: 10.1127/0340-269X/2002/0032-0337 CrossRef Full Text | Google Scholar Acclimation of leaves to contrasting irradiance in juvenile trees differing in shade tolerance Drought hardening of European beech (Fagus sylvatica L.) and silver fir (Abies alba Mill.) seedlings in mixed cultivation CrossRef Full Text | Google Scholar Determining digital hemispherical photograph exposure for leaf area index estimation CrossRef Full Text | Google Scholar Adamič PC and Dařenova E (2024) Response of beech and fir to different light intensities along the Carpathian and Dinaric Mountains Received: 01 February 2024; Accepted: 22 April 2024;Published: 08 May 2024 Copyright © 2024 Čater, Adamič and Dařenova. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) *Correspondence: Matjaž Čater, bWF0amF6LmNhdGVyQGdvemRpcy5zaQ== †ORCID: Matjaž Čater, orcid.org/0000-0002-6791-3678Pia Caroline Adamič, orcid.org/0009-0000-5644-2535Eva Dařenova, orcid.org/0000-0002-2666-6869 Volume 5 - 2022 | https://doi.org/10.3389/ffgc.2022.937404 a synchronous beech expansion has been observed for many mixed mountain forests in southeastern Europe This change is associated with the interaction of various disturbances We analyzed structural changes in the Pecka old-growth forest in Slovenia during the last century using several inventories of the tree layer the density of silver fir in the regeneration layer and in the overstory steadily decreased silver fir accounted for about 60% of the growing stock whereas in 2013 it accounted for less than 13% This is likely because of silver fir’s decline in the canopy layer due to air pollution climate change may also have played an important role as silver fir also declined in southeastern European old-growth forests where air pollution was less pronounced and ungulate densities were low A gradual decline of silver fir in the overstory resulted in a decrease of overall tree density to 231 trees ha–1 while growing stock remained relatively high at 712 m3 ha–1 Median diffuse light at 1.3 m was 3.7% and regeneration density was 19,954 ha–1 No silver fir seedlings larger than 0.2 m were recorded Regression models indicated some evidence of niche partitioning between silver fir and beech many processes may be masked by the silver fir’s avoidance strategy the Pecka old-growth forest will likely reach an alternative stable state dominated by beech in a few decades This calls for immediate reduction of ungulate populations Despite the interaction of multiple disturbances the Pecka old-growth forest has maintained a relatively high overall growing stock and succession pathway with shade-tolerant beech This indicates the intrinsic resilience of natural forests The mechanisms discussed here can be applied to the future governance of old-growth and managed montane mixed forests while repeated measurements of regeneration in old-growth forests are rare Because of the longevity of trees and the need to exclude the confounding effects of management on forest structure long-term studies of old-growth forests are needed to verify whether the ecosystem is approaching an alternative stable state This type of research is rare because of the general lack of old-growth forests and dearth of long-term studies Thanks to a tradition of forest management planning that goes back more than a century, detailed long-term data on the stand structure and regeneration of the Pecka old-growth forest are available (Hufnagel, 1893) This makes it possible to gain a long-term insight into forest developmental dynamics and to predict future trends The objectives of the research were (1) to analyze the long-term dynamics of stand structure and regeneration and their relationships (2) to examine the relationship between regeneration and ecological factors (3) to verify whether the Pecka old-growth forest is already approaching a beech-dominated alternative stable state and (4) to propose guidelines for the governance of similar old-growth and managed montane forests in the Dinaric Mountains Considering the numerous natural and anthropogenic disturbances that have occurred in the Pecka old-growth forest we hypothesized that the growing stock would be significantly reduced that light conditions on the forest floor would improve and that pioneer and semi-light-demanding tree species would be represented in the regeneration We also hypothesized that the risk of complete silver fir decline was reduced due to improved air quality and increased culling of ungulates This study took into account nine tree inventories of the entire reserve. In 1893, trees were analyzed in an area twice the size of the present forest reserve, which was reduced compared to its original size; therefore, we present data only on the ratio of silver fir to beech (Hufnagel, 1893; Boncina et al., 2002, 2003) all trees with a diameter at a breast height (DBH) greater than 10 cm in the entire old-growth forest were inventoried by tree species Age and height categories of the sampled regeneration In the first period (1980–1995) a transition from the optimal to the selection and terminal phase was recorded while in the second period (1995–2007) the share of the initial phase increased at the expense of the other three phases This is likely related to the second windthrow in 2004 and a further decline of silver fir that typically characterizes the selection phase (1) Dynamics and structure of growing stock in the last half century (2) decrease in the proportion of silver fir in the growing stock over a 120-year period and (3) percentage of forest area per developmental phase the number of trees in the range of 20–50 cm in DBH decreased The curves for cumulative and species-specific DBH distribution followed a rotated sigmoid shape when plotted on a semi-logarithmic scale (logN) (graphs not shown) the decrease in tree density following the disturbances has not yet recovered while the growing stock remained relatively stable This means that there are fewer trees with larger trunks after all the above-mentioned disturbances Development of the distribution of the number of trees by DBH class in the Pecka old-growth forest (1) Trends in total regeneration densities by year (2) Changes in beech regeneration density per height class between years (3) Trends in the proportion of silver fir per height class (4) Comparison of the proportion of silver fir in the total tree density in three developmental stages of regeneration and in two extended DBH classes regeneration data originates from 1995 and 2007 Graphs (1) and (3) include 1-year-old seedlings within the small seedling category (h < 0.2 m) To infer future trends of silver fir development, its proportion in successive regeneration height and DBH classes are shown (Figure 3.4) Declines were observed over time in all developmental stages of the silver fir population This is most evident in the developmental stage between 0.2 and 5.0 m in height where the chronic overbrowsing of recent decades is most directly reflected we also found sycamore maple and Norway spruce during the 2007 inventory Their share in 1-year-old seedlings was 2% Among smaller seedlings (h < 0.2 m) while among larger seedlings and saplings (0.2 ≤ h < 2.5 m) we did not find any species other than beech sycamore maple and beech regeneration (older than 1-year-old seedlings and h < 2.5 m) In 54 years and seven regeneration inventories, no silver fir taller than 0.5 m was found in the regeneration. Low overall silver fir density was noted as early as 1963 (Figure 4.1). The peak of silver fir seedling density occurred in the 1980s during the acute decline of silver fir. It was followed by a marked decline that continues to this day. In all inventories, at least 50% of silver fir seedlings were damaged by deer (Figure 4.2) Beech browsing damage was assessed only in the last two inventories moderately browsed and severely browsed beech seedlings were 56 (1) Dynamics of silver fir regeneration density by age class and (2) browsing damage to small silver fir seedlings by year the average density and cover of small silver fir seedlings (h < 0.2 m) were 351 ha–1 and 0.1% while the average density and cover of small beech seedlings was 5,046 ha–1 and 3.8% While there were no larger silver fir seedlings the density and coverage of beech seedlings (0.2 m ≤ h < 1.3 m) were 10,351 ha–1 and 15.5% while small beech sapling density (1.3 m ≤ h < 2.5 m) and coverage were 2,180 ha–1 and 16.1% The best predictors for beech sapling coverage were larger beech seedling coverage (sD = 35.4) followed by total basal area (sD = 20.7) Results of the GLM analysis for silver fir presence (h < 0.2 m) and beech seedling and sapling cover predicted by light components and beech seedling coverage for 164 regeneration plots Effect display for significant factors in the regression model for the coverage of beech between 0.2 and 1.3 m height The gray areas represent 95-percent confidence envelopes around the fitted effects Small silver fir seedling presence was associated with the optimal phase while larger beech seedlings were associated with other developmental phases Small beech seedling and sapling coverage were not associated with developmental phases Small and larger beech seedling cover were negatively correlated with rockiness Small silver fir seedlings were frequently present under beech regeneration While the coverage of small beech seedlings indicated a positive relationship with the basal area of beech the relationship between small beech sapling coverage and total basal area was negative This is probably related to the low light levels in the understory and the low water holding capacity of soils on limestone All developmental stages of regeneration were at least indirectly positively associated with higher light levels; for example small beech sapling density was negatively related with total basal area This suggests that light is a resource that is in short supply in this type of old-growth forest We did not find large differences in the light environment at different heights in the understory It also appears that microsite conditions (light climate CWD) were less important than the overall conditions in the middle and upper stand layers we estimate that most silver firs with DBH < 20 cm in montane mixed old-growth forests are under canopy and stressed and do not produce seeds The research results document how combinations of natural and anthropogenic disturbances can completely change the tree species mixture of old-growth forests in a relatively short period of time compared to their developmental cycle the Pecka old-growth forest is also characterized by its location at the border of mixed montane forests which is why the silver fir decline has been particularly pronounced it can serve as a warning for other old-growth mixed forests in central and western Europe which are threatened with a similar fate The high growing stock and well-preserved forest microclimate indicates the high resilience of mixed montane forests Although the disturbances most likely deviated from the natural disturbance regime the forest has recovered due to the advanced regeneration of shade-tolerant beech while successional pathways with pioneer species have not yet been activated it does not seem appropriate to overemphasize the importance of pioneer stages in managed forests for adaptation to a higher intensity of natural disturbances the development of pioneer stages is more probable even at lower disturbance intensities managed forests are also in an advantageous position because of the possibility to support endangered species through silvicultural measures such as planting protection from browsing and competition regulation extremely endangered old-growth forests such as Pecka serve as a warning that changes in the management of ungulate populations are long overdue and DR developed the conception and the method of the study set up and performed the regression model statistics and wrote the first draft of the manuscript This research was supported by the Slovenian Research Agency (ARRS) under grants P4-0059 and J4-1765 and by the Pahernik Foundation Long-term use of uneven-aged silviculture in mixed mountain Dinaric forests: a comparison of old-growth and managed stands Effects of gap size and within-gap position on seedlings establishment in silver fir stands Google Scholar Regional and global emissions of air pollutants: recent trends and future scenarios doi: 10.1146/annurev-environ-052912-173303 CrossRef Full Text | Google Scholar Interactions between forest stands and microclimate: ecophysiological aspects and consequences for silviculture CrossRef Full Text | Google Scholar An indicator approach to capture impacts of white-tailed deer and other ungulates in the presence of multiple associated stressors Comparison of structure and biodiversity in the Rajhenav virgin forest remnant and managed forest in the Dinaric region of Slovenia CrossRef Full Text | Google Scholar current status and future prospects of uneven-aged forest management in the Dinaric region: an overview CrossRef Full Text | Google Scholar Comparison of the two main types of selection forests in Slovenia: distribution Long-term changes in tree species composition in the Dinaric mountain forests of Slovenia CrossRef Full Text | Google Scholar Comparative dendroclimatic study of Scots pine CrossRef Full Text | Google Scholar Disturbance interactions: characterization CrossRef Full Text | Google Scholar Drought-induced decline and mortality of silver fir differ among three sites in Southern France The rise of angiosperms pushed conifers to decline during global cooling Local seed dispersal in European silver fir (Abies alba Mill.): lessons learned from a seed trap experiment CrossRef Full Text | Google Scholar Jelka (Abies alba Mill.) v pomladku pragozda Pecka v zadnjih tridesetih letih Google Scholar Regeneration dynamics in a Norway spruce plantation on a silver fir-beech forest site in the Slovenian Alps CrossRef Full Text | Google Scholar Silver Fir Decline in Mixed Old-Growth Forests in Slovenia: An Interaction of Air Pollution CrossRef Full Text | Google Scholar Gap recruitment and partitioning in an old-growth beech forest of the Dinaric Mountains: influences of light regime Stand dynamics of Dinaric old-growth forest in Slovenia: are indirect human influences relevant CrossRef Full Text | Google Scholar Regeneration gap and microsite niche partitioning in a high alpine forest: are Norway spruce seedlings more drought-tolerant than beech seedlings Structure of silver fir (Abies alba Mill.) natural regeneration in the ‘Jata’ reserve in Poland CrossRef Full Text | Google Scholar Ecology and silviculture of silver fir (Abies alba Mill.): a review CrossRef Full Text | Google Scholar Grundlagen zur Beurteilung des Wildverbisses im Gebirgswald Google Scholar The growth potential of understorey silver fir and Norway spruce for uneven-aged forest management in Slovenia CrossRef Full Text | Google Scholar Disturbance history and dynamics of an old-growth mixed species mountain forest in the Slovenian Alps CrossRef Full Text | Google Scholar Water shortage affects the water and nitrogen balance in central European beech forests A review of damage by mammals in north temperate forests: 3 CrossRef Full Text | Google Scholar The effect of plant competition and simulated summer browsing by deer on tree regeneration CrossRef Full Text | Google Scholar Google Scholar Google Scholar Stand structural complexity of mixed old-growth and adjacent selection forests in the Dinaric Mountains of Bosnia and Herzegovina Comparative structural dynamics of the janj mixed old-growth mountain forest in bosnia and herzegovina: are conifers in a long-term decline Google Scholar Forest decline in Europe: development and possible causes light availability and vigour determine the response of Abies alba saplings to leader shoot browsing CrossRef Full Text | Google Scholar Europäische Urwälder der Bergstufe Google Scholar CrossRef Full Text | Google Scholar CrossRef Full Text | Google Scholar Vegetation of the Pecka virgin forest remnant Google Scholar Razvoj inicialne faze na vetrolomni povrsini v prajozdnem ostanku Ravna gora (Development of the initial phase after windthrow in the virgin forest remnant Ravna gora) Google Scholar Utjecaj ekoloskih i strukturnih cinilaca na prirodno pomladivanje prebornih suma jele i bukve u Gorskom kotaru Google Scholar Struktureller und entwicklungsdynamischer vergleich der fichten-tannen-buchen-urwälder rothwald-niederösterreich und corkova uvala-kroatien CrossRef Full Text | Google Scholar Darcy’s law predicts widespread forest mortality under climate warming CrossRef Full Text | Google Scholar “Functional relationships between old-growth forest canopies understorey light and vegetation dynamics of old-growth forests,” in Old-Growth Forests Google Scholar Pomlajevanje in nekatere razvojne znacilnosti bukovega in jelovega mladovja v pragozdu na Rogu Google Scholar Air and soil microclimates of deciduous woodland compared to an open site CrossRef Full Text | Google Scholar Impact of wild ungulates on forest regeneration and tree composition of mountain forests in the Western Italian Alps CrossRef Full Text | Google Scholar Intermediate wind disturbance in an old-growth beech-fir forest in southeastern Slovenia CrossRef Full Text | Google Scholar Simultaneous influence of canopy decline and deer herbivory on regeneration in a conifer-broadleaf forest A dendroecological reconstruction of disturbance in an old-growth Fagus-Abies forest in Slovenia CrossRef Full Text | Google Scholar Regeneration patterns after intermediate wind disturbance in an old-growth Fagus-Abies forest in southeastern Slovenia and dynamics in an old-growth forest landscape of southeastern Europe and mortality rates on coarse woody debris and forest floor—a study from a mixed beech forest in the Western Carpathians Gebirgsnadelwälder: Praxisorientierter Leitfaden für eine standortgerechte Waldbehandlung Google Scholar Conservation genetics of small relic populations of silver fir (Abies alba Mill.) in the northern Apennines “The research in Croatian virgin forests and the application of results to natural forests,” in Skrb Za Hrvatske Sume Od 1946 do 1996.: Unapredenje Proizvodnje Biomase Sumskih Ekosustava Dinarski Jelovo-Bukovi Gozdovi Na Kocevskem/Die Dinarischen Tannen-Buchenwälder im Gebiete von Kocevje Ljubljana: Slovenian Academy of Science and Art Google Scholar R Core Team (2019) A Language and Environment for Statistical Computing Google Scholar CrossRef Full Text | Google Scholar Architecture of Fagus sylvatica regeneration improves over time in mixed old-growth and managed forests CrossRef Full Text | Google Scholar Comparison of four methods for estimating relative solar radiation in managed and old-growth silver fir-beech forest Google Scholar Gap regeneration patterns in relationship to light heterogeneity in two old-growth beech-fir forest reserves in South East Europe Ugibanje i obnavljanje jele u prebornim sumama Gorskog Kotara Google Scholar Are overabundant deer herds in the eastern United States creating alternate stable states in forest plant communities Google Scholar Forest Reserves in Slovenia - Old-Growth Forest Pecka Ljubljana: Univerza Edvarda Kardelja v Ljubljani Google Scholar Effect of tree layer and microsite on the variability of natural regeneration in autochthonous beech forests European beech (Fagus sylvatica L.) and silver fir (Abies alba Mill.) rotation in the Carpathians–A developmental cycle or a linear trend induced by man Mixed Effects Models and Extensions in Ecology with R CrossRef Full Text | Google Scholar Fidej G and Rozenbergar D (2022) Toward a Beech-Dominated Alternative Stable State in Dinaric Mixed Montane Forests: A Long-Term Study of the Pecka Old-Growth Forest Copyright © 2022 Diaci, Adamic, Fidej and Rozenbergar. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) *Correspondence: Jurij Diaci, SnVyaWouRGlhY2lAYmYudW5pLWxqLnNp Metrics details The aim of this study was to elucidate how different nursery production methods influence the composition of and relationship between soil and root community levels of Abies alba we quantified the responses of samples of both community-level fine roots and surrounding soil to environmental changes evoked by various seedling production methods Fungi levels were identified based on their ITS 1 region and 5.8 S rDNA component Analysis was conducted using Illumina SBS technology and the obtained sequences were compared with reference samples deposited in the UNITE Chemical analysis of the soil was also performed Different nursery production methods resulted in a strong decoupling in the responses of fungal community levels between soil and roots Changes in growth conditions imposed by production methods were significant in determining species composition We found differences in fungal communities among functional groups of samples the dominant species of mycorrhizal fungi were Tylospora asterophora Mycorrhizal fungi in roots included Tuber anniae Specific soil substrate conditions significantly influenced fungal community composition leading to an increase in abundance of mycorrhizal fungi the effect of interactions between nutrient abundance and light availability on fungal community composition remains poorly understand due to difficulties in assessing all these variables the possible ways in which technologies associated with silver fir production can modify fungal composition have received little Location of the study site in the Międzylesie Forest District of the National State Forest and location of specific forest nurseries within the Międzylesie Forest District C—nursery under Scots pine canopy and natural regeneration in a silver fir stand Share [%] of phyla in fungal communities around fine roots and in soil represented. More information regarding individual treatments can be found in “Materials and methods” and “Molecular identification of fungal communities” sections The highest value for Margalef’s index, which defined relative species richness in relation to the total number of species and total number of all specimens in a given community, was recorded for the fungal community present in fine roots in the IIR treatment (3-year-old silver fir seedlings transplanted after their second year of growth in an open field nursery; Table 2) the lowest community abundance was found in the soil of the IIIS treatment (nursery production in containers with a peat bed) The fine roots of silver fir were characterised by a higher Shannon’s diversity index than that of the fungal community present in the soil reaching a maximum in fine roots in the IR treatment (3-year-old silver fir seedlings grown in an open field nursery) and a minimum in soil in the IIIS treatment which describes the proportions of individual species in the community and is defined by Shannon’s evenness index was highest for the fungal community in soil from the IR treatment and lowest in soil from the IIIS treatment As in the case of Shannon’s diversity index higher values for Shannon’s evenness index were obtained for the fungal community of fine roots which expresses the probability of finding two specimens belonging to the same species in a random sample was highest for the fungal community in soil from the IIIS treatment and lowest in fine root samples from the IR treatment Lower values of this index were obtained for the fungal community of fine roots than for that of soil The highest values of the dominance index were obtained for the fungal community in roots from the VR treatment (nursery under a Norway spruce canopy) whereas the lowest values were found in soil from the IIS treatment The analysis of variance resulted in χ2 = 131,265 for the structure of functional groups of fungi on roots The critical value of this statistic for the significance level p = 0.01 was χ2 = 59.70 indicating that the structure of the numbers of individual functional groups varied greatly both in the case of soil fungi and fungi isolated from roots It was assumed that the numbers of OTUs in individual groups obtained from soil and roots would correlate as the same fungi should be found on roots as in the soil in which the roots were growing A comparison of the numbers of OTUs in individual taxa from soil and from roots provided a Pearson’s correlation coefficient of r = 0.4883 (p = 0.01) although it was far from fully consistent and defined as moderate Linear correlation coefficients between quantitatively determined properties of soil and nursery container substrate, and the numbers of isolated fungi belonging to identified functional groups are presented in Table 3 The presence of mycorrhizal fungi in soil was related to a high ammonia nitrogen content and high acidity but the presence of these fungi on roots was not dependent on soil nutrient abundance High levels of phosphorus and magnesium did not promote the presence of saprotrophic fungi in soil A Shepard diagram indicated scatter around the regression between the inter-point distances in the final configuration (between each pair of species communities) and their original dissimilarities (Fig. 5), suggesting that original dissimilarities are well preserved in the reduced number of dimensions in the final configuration. Shepard diagram displaying statistics for goodness of fit between ordination distances and observed dissimilarity Only the most abundant fungal species were included (share > 1%) Results of the ANOSIM showed that there was a statistically significant difference (R = 0.34, p = 0.02) between fungal communities around fine roots and those in soil. In the case of nursery production, the NMDS indicated that a lack of difference between fungal species could not be rejected (R = 0.04, p = 0.42; Fig. 6). exiqua were considered to be good indicators because their Iv values were all very close to 1 indicating their strong association with soil A total of 51 species of fungi were identified could be identified as a diagnostic species with its occurrence restricted to soil (Iv = 1.000 A Shepard diagram computed for species of mycorrhizal fungi suggested that original dissimilarities were well preserved in the reduced number of dimensions in the final configuration (Fig. 7). Shepard diagram displaying statistics for goodness of fit between ordination distances and observed dissimilarity for communities of mycorrhizal fungi only The NMDS for mycorrhizal fungi revealed that samples were distinct based on place of sampling (root or soil; Fig. 8). The closer two points (samples) were on the graph, the more similar those points were considered to be. The ANOSIM statistic indicated a significant difference between species of mycorrhizal fungi based on place of sampling (R = 0.23 but no difference among methods of silver fir seedling production in the nursery (R = 0.0 the null hypothesis stating a lack of difference between species of mycorrhizal fungi could only be rejected in the case of place of sampling we found that the composition of soil fungal community depended on method of seedling production and was related to the soil conditions of cultivation sites We also observed that soil and root fungal communities varied in functional group dominance—mycorrhizal fungi dominated in fine roots whereas saprotrophs were primarily present in soil substrate our study of fungal communities also confirmed the presence of Cenococcum geophilum Although a greater abundance of short- or medium-distance mycorrhizal types may mirror growth conditions of forest nurseries in the early stages of seedling growth short distance exploration may not provide enough water to fulfil the water demands of older trees long taproots may not enhance foraging in deep soil layers although fungal composition and richness may be related to canopy conditions we observed in our study that the greatest richness was present within the IIR (SP21) treatment as a result of a great abundance of unique species In fine root samples from the IIR treatment the following species represented the majority: Tuber anniae anniae was a good indicator species of the root community because it only occurred in that community Amanita rubescens was identified as an indicator species making primary roots more accessible to other symbionts and pathogens As the role of PAC in fir-associated fungal communities has not yet been recognised dark septate endophytes in the fir rhizosphere/fungal community require further research which may be explained by variation in the responses of roots to the changes in growth conditions experienced by containerised seedlings in comparison to those faced by seedlings in open and canopied nurseries Lower levels of colonisation by mycorrhizal fungi is generally attributed to high fertilisation or shaded growth conditions which can both reduce the engagement of mycorrhizal fungi in resource acquisition and the availability of carbohydrates if application of high fertilisation in a container in the early stages of development reduces the ability of fir seedlings to establish mycorrhizal symbiosis at later stages of growth in the field Methods of fir production that prioritise allocation of resources to leaves to maximise carbon gain which could in turn threaten survival by reducing the probability of establishing beneficial mycorrhizal symbiosis The relatively low proportion of common species in the mycorrhizal community of containerised fir seedlings may be an obstacle to their further survival and highlights the requirement for artificial manipulation of the growth substrate by application of mycorrhizal inoculum The local conditions of the site likely did not allow for switches and adjustments of fungal partners to new conditions or limited the abundance of ectomycorrhizal fungi in the soil community the greatest diversity in the community of soil fungi was observed in samples from the natural regeneration site for fir whereas the greatest diversity in the community of root fungi was found in samples from the 3-year-old (2/1) fir seedlings transplanted after their second year of production The abundance of mycorrhizal fungi and low number of pathogens in the community of soil fungi from forest nurseries producing fir seedlings is a good sign indicating the quality of the nursery environment We found that similarities in the taxonomic composition and the population size of fungi in soil and on seedling roots existed and were demonstrable The relationship between the taxonomic composition and abundance of fungi and soil properties remains far from evident although our study confirmed a positive effect of soil ammonia nitrogen content and acidity on mycorrhizal fungi as well as a similarly negative effect of phosphorus and magnesium content on saprotrophic fungi Identification of soil fungal communities from nurseries producing silver fir seedlings made it possible to determine the spectrum of mycorrhizal fungi characteristic of this tree species at a given age (3 years) Tuber anniae was a good indicator species of root group because it occurred only in root samples as they were present in roots at all sites and were largely restricted to root samples fungal presence was very low in the container method of production treatment (peat substrate) indicating that artificial mycorrhization could be beneficial for the sustainable development of seedlings via this production method were collected from forest soil in a mature fir stand with natural regeneration The plant collection and use was in accordance with all the relevant guidelines and legislation Permissions were obtained from the nursery owners for collection of samples 30 soil samples (five samples per each treatment: IS VIS) and 30 fine-root samples from 3-year-old seedlings (five samples per each treatment: IR Samples were collected from soil at a maximum depth of 25 cm and each sample collection site was 20 m apart Individual soil samples were placed in a container and then thoroughly mixed to create a representative sample (approx Samples of fine roots were collected from the same plots (nested in treatments) as those from which soil samples were taken Root samples were packed into paper envelopes and soil samples were packed into plastic bags Each sample was packed separately and immediately taken to the laboratory where seedlings were removed from the ground and then root branches within the exposed root system were randomly selected Comparably sized subsamples of fine root branches (2 cm in length) were placed in 2-ml screw cap tubes The soil samples were analysed by the Seed Testing Station of the National Forests Research and Implementation Centre of State Forest in Bedoń N-NO3 and N-NH4 via an electrochemical method following extraction in 0.03 N acetic acid44 The reaction mixture consisted of 2.5 µl DNA and 12.5 µl 2× PCR MIX (A&A Biotechnology) with deionised water added to reach a final volume of 25 µl Amplification was run in a thermocycler with a cycle consisting of preliminary denaturation (94 °C the product was visualised on 1% agarose gel using Midori Green Advance DNA (Genetics) for staining The obtained product was purified and sequenced using SBS technology by Illumina (Genomed S.A. Sequencing was performed on a MiSeq sequencer in paired-end (PE) technology Negative samples (without DNA) were also sequenced to remove artifacts The raw data used in the compilation of the results can be found in Supplementary Appendix 3 and https://doi.org/10.6084/m9.figshare.23404070.v1 This process resulted in the creation of a table of OTUs OTU sequences not belonging to Fungi or Oomycota were removed from further analysis Rarefaction curves were determined for the obtained OTU library Comparisons between treatments (the comparison of proportions among different fungal phyla) were made using Pearson’s (χ2) test of homogeneity and Pearson’s linear correlation coefficients Values of indices obtained in the quantitative analysis were compared using a two-way analysis of variance the more dissimilar are the analysed groups Statistical significance was calculated by permuting the grouping vector to obtain the empirical distribution of the R value under the null hypothesis We conducted ANOSIM using the Vegan package in R environment (R Development Team and used 9999 permutations to assess the statistical significance of the test The data presented in this study are available on Baranowska, Marlena (2023). fungal community of 3-year-old silver fir (soil and fine roots).xlsx. figshare. Dataset. https://doi.org/10.6084/m9.figshare.23404070.v1 Kolekcja klonów jodły pospolitej (Abies alba Mill.) w Nadleśnictwie Międzylesie A strategy for restitution of silver fir (Abies alba Mill.) in the Sudety Mountains Silver fir (Abies alba Mill.) restitution in the Sudety Mountains—The characteristics of restored trees Adaptacja i wzrost potomstwa drzewostanów jodły pospolitej (Abies alba Mill.) na uprawie testowej w Nadleśnictwie Złotoryja Przemiana sposobu zagospodarowania lasu na przerębowy na przykładzie jednostki kontrolnej Chełmsko w Nadleśnictwie Kamienna Góra The soil fungal communities in nurseries producing Abies alba Pollen morphology and variability of Abies alba Mill Northern provenances of silver fir differ with acclimation to contrasting light regimes growth and photochemical efficiency of silver fir seedlings produced with different technologies Biotic and abiotic drivers of the tree growth and mortality trade-off in an old-growth temperate forest Effects of soil abiotic and biotic factors on tree seedling regeneration following a boreal forest wildfire An overview on drought induced changes in plant growth Host and habitat filtering in seedling root-associated fungal communities: Taxonomic and functional diversity are altered in ‘novel’ soils Effect of irrigation dose on powdery mildew incidence and root biomass of sessile oaks (Quercus petraea (Matt.) Liebl.) Effects of soil compaction and light on growth of Quercus pyrenaica Willd Substrate influences the height of one- and two-year-old seedlings of silver fir and European beech growing in polystyrene containers Fungal biodiversity and their role in soil health bacterial and fungal communities at the soil surface Long-term fertilization alters soil properties and fungal community composition in fluvo-aquic soil of the North China Plain Fungal communities in mycorrhizal roots of conifer seedlings in forest nurseries under different cultivation systems The fungal collaboration gradient dominates the root economics space in plants Managing plant surplus carbon to generate soil organic matter in regenerative agriculture Root system development and field establishment: Effect of seedling quality Rewitalizacja gleb w szkółkach leśnych (Centrum Informacyjne Lasów Państwowych Lactarius ectomycorrhizae on Abies alba: Morphological description Host effects on ectomycorrhizal fungal communities: Insight from eight host species in mixed conifer–broadleaf forests Diversity and species distribution of ectomycorrhizal fungi along productivity gradients of a southern boreal forest Ectomycorrhizal fungal communities in high mountain conifer forests in central Mexico and their potential use in the assisted migration of Abies religiosa Shift in fungal communities and associated enzyme activities along an age gradient of managed Pinus sylvestris stands Root-associated fungal communities from two phenologically contrasting silver fir (Abies alba Mill.) groups of trees Ectomycorrhizal communities associated with silver fir seedlings (Abies alba Mill.) differ largely in mature silver fir stands and in Scots pine forecrops The root-symbiotic Rhizoscyphus ericae aggregate and Hyaloscypha (Leotiomycetes) are congeneric: Phylogenetic and experimental evidence Lineages of ectomycorrhizal fungi revisited: Foraging strategies and novel lineages revealed by sequences from belowground Root mass carbon costs to acquire nitrogen are determined by nitrogen and light availability in two species with different nitrogen acquisition strategies Competitiveness of endophytic Phialocephala fortinii s.l.–Acephala applanata strains in Norway spruce roots Mycorrhiza reduces adverse effects of dark septate endophytes (DSE) on growth of conifers The effect of simulated warming on root dynamics and soil microbial community in an alpine meadow of the Qinghai-Tibet Plateau Trichoderma as biostimulant: Exploiting the multilevel properties of a plant beneficial fungus Arbuscular mycorrhizal fungi act as biostimulants in horticultural crops Metodyka analiz laboratoryjnych gleb i roślin (Uniwersytet Przyrodniczy we Wrocławiu Instytut Nauk o Glebie i Ochrony Środowiska Właściwości gleb leśnych i metody ich oznaczania (Instytut Ochrony Środowiska Illumina metabarcoding of a soil fungal community Organization of ribosomal DNA in the basidiomycete Thanatephorus praticola Fungi associated with Cyclaneusma needle cast in Scots pine in the west of Poland PIPITS: An automated pipeline for analyses of fungal internal transcribed spacer sequences from the Illumina sequencing platform A circadian gene expression atlas in mammals: Implications for biology and medicine Bengtsson-Palme, J. et al. Improved software detection and extraction of ITS1 and ITS2 from ribosomal ITS sequences of fungi and other eukaryotes for analysis of environmental sequencing data. Methods Ecol. Evol. https://doi.org/10.1111/2041-210X.12073 (2013) The UNITE database for molecular identification of fungi: Handling dark taxa and parallel taxonomic classifications Naïve Bayesian classifier for rapid assignment of rRNA sequences into the new bacterial taxonomy Ribosomal Database Project: Data and tools for high throughput rRNA analysis DEEMY—The concept of a characterization and determination system for ectomycorrhizae Ecological Diversity and Its Measurement (Springer Marine mammals harbor unique microbiotas shaped by and yet distinct from the sea How to bloom the green desert: Eucalyptus plantations and native forests in Uruguay beyond black and white perspectives Ecological patterns in multivariate assemblages: Information and interpretation of negative values in ANOSIM tests Analysis of similarities (ANOSIM) for 2-way layouts using a generalised ANOSIM statistic with comparative notes on permutational multivariate analysis of variance (PERMANOVA) Improving indicator species analysis by combining groups of sites Download references This study was financed by the State Forests National Forest Holding (Państwowe Gospodarstwo Leśne Lasy Państwowe—PGL LP) Programme of restitution of silver fir resources in the Sudeten Mountains—part 4 and part 5 The minor part of these results was presented at the international IUFRO Conference—Abies & Pinus 2022 “Fir and pine management in a changing environment: Risks and opportunities”; 19–22.09.2022; Sarajevo Natalia Kartawik & Wojciech Kowalkowski M.B.; writing-original draft preparation: M.B. W.K.; validation: W.B.; reviewing and editing: M.M.H. Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations Download citation DOI: https://doi.org/10.1038/s41598-023-48047-y a shareable link is not currently available for this article Sign up for the Nature Briefing newsletter — what matters in science The hard work of preparing for Christmas is over by Thanksgiving for Casey Grogan But the weeks leading up to Thanksgiving — and especially the week before — are the busiest of the year He owns or leases some 500 acres in the Willamette Valley and grows hundreds of thousands of trees he and other Oregon tree farmers are up from dawn to dusk harvesting packing and shipping trees to vendors all over the world Oregon is the biggest Christmas tree producer in the United States Growers and farmworkers harvested 4.7 million trees in 2017 according to the Pacific Northwest Association of Christmas Trees though Oregon also is the largest producer of Douglas firs in the country Some Oregon farms offer customers a chance to visit and chop down their own trees His trees are shipped across state and country lines to places as close as Seattle and as far away as Mexico Vendors want trees in their lots by Thanksgiving So the week before that is all-hands-on-deck Temperatures are only just beginning to climb above freezing already wrapped and tagged with different colored ribbon based on species and height Each tree will be lifted onto a conveyer belt A team of 4-5 people rotate in the semi-trailer hoisting the trees from the conveyer belt into the truck Griselda Castillo tallies every tree on a piece of paper to ensure each retailer gets exactly what it ordered They even give the farm its name: Silver Bells named for the silvery-blue tint on Grogan’s signature Silver Bells Blue Noble fir The broader species are native to the Pacific Northwest but the Silver Bells Blue he grows are a result of the tree’s migration to Denmark more than 100 years ago Danish horticulturists grew trees from seeds they brought from the Pacific Northwest and selectively kept the “best” ones: blue needles They grow more quickly and cost less to produce Douglas firs can grow at lower elevations and in warmer temperatures They are the Goldilocks choice of Christmas trees They're more “grower-friendly" than Nobles because they are more resilient but prettier than Douglas firs Nordmann firs were just 4% of Oregon’s Christmas tree stock in 2017; but their popularity is increasing Joel Amaral remembers his first day on the job in the first field of trees he ever planted Grogan considers him his “right-hand man.” He has planted countless trees since then And Amaral’s grown rather fond of them all standing in a field of freshly-cut trees waiting to be wrapped Amaral and his coworkers — three others year-round more during harvest season — meet the trees as seedlings The small seedlings are then planted in a freshly-prepared field — side-by-side Amaral and his team play a direct role in shaping these trees into the perfect cone-shaped Christmas trees people have grown to love Evergreen trees’ branches grow in clusters called a “leader,” carries buds that will eventually become their own branches Christmas tree farmers know how to clip buds depending on how they want the tree to grow They literally shape each tree as it grows But not all trees grown in the same field are ready at the same time The ones that aren’t are left for another year or two Grogan and his team will clear-cut the whole field and prepare it for the next batch It also makes Christmas tree farming a hard and "high-risk" industry to get into since you don’t make money until you sell trees who still help with business and logistics sometimes said in the on-farm office that doubles as Grogan’s brother’s house But even with his family’s help and a degree in Agricultural Business from Oregon State University Grogan said he still needed a new farmer loan to get started His parents bought it when he was six months old That it turned into a Christmas tree farm was almost an accident Charlie and Sally Grogan bought a home on 20 acres in 1976 complete with a field of newly-planted Christmas trees The family decided to grow the trees to maturity and quickly became enamored Most “new” Christmas tree farmers these days are people who already farm something else and want to diversify It’s also an industry that was cut in half more than a decade ago The 2008 recession hit Christmas tree farmers hard The ones that remained had to scale back their operations Consumers didn’t feel the crunch until the next rotation cycle Fewer trees planted in 2008 meant fewer trees for sale a decade later according to the National Christmas Tree Association “you’re going to find a tree,” Grogan said The median price of a fresh cut tree last year was $69.50 Related:Christmas tree permits now available for Oregon national forests A couple of miles up the road from the main farm another truck is brimming with freshly-cut trees to be taken back to the shipping lot It’s an entirely different scene from the main property pointing to a field that has been recently clear-cut The recession was the biggest change to the industry Grogan has seen slower change he and the industry must now confront: that of the climate But Oregon’s beloved Nobles do best in cooler temperatures The deadly heat dome in 2021 killed a whole field of Grogan's young trees “They held on for two or three days,” he said Grogan said he just bought more land on a farm at an elevation of 1,700 feet to plant new trees “We’re trying to move uphill instead of down,” he said Nordmanns also are more resistant to heat and can handle the heavy rain that falls lower in the valley which also may help explain their rise in popularity with growers They also are more resistant to pests — trees' second-biggest threat but a warming climate is making those changes more urgent Oregon State researchers are studying the growing practices that might be more resistant to heat like applying fertilizer at the time of planting (instead of shortly after) A few more acres away from the clear-cut field Most stand proud and green; but at least one in every row has turned that reddish-brown that signals death there are a lot of dead trees,” Grogan said Joel Amaral hasn’t had his own Christmas tree since his wife died three years ago Grogan puts a tree in his house every year he and his family pick and harvest a good one they take the “Charlie Brown” tree — one that probably wouldn’t sell What Grogan likes most about the holiday season is to think about how many families will sit around his trees on Christmas morning There was a screen above the field that displayed the number of people in attendance: somewhere in the ballpark of 40,000 (OSU’s Reser Stadium can hold up to 43,000 people) “It was almost equal to the number of trees we had cut that year,” Grogan said He looked out at the sea of people and imagined each and every one of them — plus their families — in front of one of his tree Christmas trees can survive at least 40 days out of the ground Grogan said — if you care for them properly Evergreen trees produce a “sap seal” that prevents water from being absorbed The seal forms on the bottom of freshly-cut trees “They key is to put [trees] in water while the sap seal is still broken,” Grogan said The easiest way to do that is to re-cut the bottom of your tree before you put it in water When the season is over, recycle your tree or find a local organization who will take it off your hands in exchange for a suggested donation to a nonprofit Shannon Sollitt covers agricultural workers through Report for America, a program that aims to support local journalism and democracy by reporting on under-covered issues and communities. Send tips, questions and comments to ssollitt@statesmanjournal.com Matt Bratlien saw something odd in the spacious suburb of Silver Firs A six-wheeled robot with the Amazon Prime logo on its sky-blue carapace was driving up and down the sidewalks and curbs Bratlien had encountered Scout a delivery robot Amazon is testing in the area including by ferrying real orders to customers Here’s what he didn’t see: Countless digital clones crawling through a virtual copy of the neighborhood that Amazon created with scans of the area collected by lasers Amazon knows a lot about the world thanks to data from its vast retail business and cloud computing platform It knows a 2-square-kilometer zone of Snohomish County in unusual detail—down to the position of weeds sprouting through the drainage grates The company’s digital copy mirrors the position of curbstones and driveways within centimeters and textures like the grain of asphalt within millimeters but declines to say exactly where they roam County Executive Dave Somers says Amazon consulted him and the sheriff’s office prior to launching and says he supports the project but doesn’t know exactly where Amazon tests Bratlien’s Facebook post geotagged Scout in Silver Firs a community of 21,000 with curving streets branched with cul-de-sacs; another person posted a photo of Scout in the same neighborhood Months after Amazon announced Scout was in testing Washington Governor Jay Inslee signed a bill that regulates delivery robots limiting their speed and weight and barring them from jaywalking This content can also be viewed on the site it originates from Matt Bratlien posted this image on Facebook after encountering an Amazon robot in March Amazon’s mapping and simulation technology is not just a research tool It could also help Amazon deploy the robots to new neighborhoods when they’re ready for general use “We've built it such that we can scale up to an entire city,” Scott says By the time Scout rolls into a new town for the first time its control system will have likely “seen” every seam in the pavement thousands of times before Amazon is a relative latecomer to the young world of delivery robots. Startup Starship Technologies, founded by two creators of Skype, and competitor Marble were delivering pizza and other food orders in early 2017 Amazon’s project appears to have begun in earnest late that year when it acquired Dispatch and the startup’s three cofounders joined Amazon Amazon’s size and deep investment in logistics set the company’s project apart. Scout joins a delivery fleet that includes 40 aircraft and 30,000 delivery vans. The company has deep experience with robotics; it employs more than 200,000 of them inside its retail operations to move shelves, load pallets, and sort packages Yet to drive safely around Silver Firs or any other neighborhood Scout must cope with challenges not seen inside Amazon’s finely controlled warehouses the robots are programmed to slow down and steer around people or animals—or stop if they come close But making Scout reliably self-sufficient requires gathering as much data as possible A virtual robot goes to work inside a digital recreation of a suburb north of Seattle Amazon built its simulated suburb in part with data from a cart similar in size to Scout that was towed behind a bicycle, capturing images using cameras and lidar, a type of 3D laser scanner used on autonomous car projects The company filled in its map with 3D data from aircraft surveys Amazon has experimented with a more powerful lidar too large for the bicycle cart although Scott declines to identify how it travels views from inside Amazon’s simulation can be hard to distinguish from photos of Silver Firs Look more closely and you notice glitches like smeary foliage Scott says his team has evidence that their fake world is accurate enough that algorithms trained on it also work on real world data Scout’s control system includes computer vision software that labels pixels in images from the robot’s camera as grass A version of that software trained on 400,000 hand-labeled photos of the neighborhood scored 0.98 on an internal accuracy test with a maximum score of 1 A version trained using only images from the virtual world scored 0.94 Scott says that’s close enough to show that the simulator can help Scout understand the real world; progress doesn’t depend entirely on collecting and labeling real photos He predicts even higher accuracy from training with a combination of real and simulated data The WIRED Guide to Artificial IntelligenceOne of the robot’s trickier challenges is navigating curb ramps when it needs to cross the street Collecting data solely by repeatedly driving the ramps would be time consuming Amazon engineers can minimize that by sending virtual Scouts through curb ramps at varied trajectories from different perspectives Kevin Peterson, cofounder and CEO of Marble, which is testing delivery robots in Concord, California, says his company has experimented with high-resolution simulations but found they weren’t useful enough. Instead, he says, Marble has used a technique called generative adversarial networks—also used in AI art projects—to create extra data to train its robots’ software Some unknowns about Amazon’s robotics project are questions of economics, not engineering. Scott says his team is aiming to make Scout “100 percent” autonomous—but can also imagine robots that sometimes call home for help. “Someone could manage hundreds of bots,” he says. The robot-to-human ratio that makes Scout a practical delivery option will depend on how often it needs help, and the financial costs and payoffs of robot package hauling. Scott says Amazon is focused on Scout for suburban deliveries for now, although Peterson of Marble says the economics are best in denser urban areas where drop offs are closer together. Amazon says Scout can travel miles at a time on a single charge, depending on the terrain and its loads. Bratlien, who unexpectedly met Scout on the streets of Silver Firs in March, was prompted to think about how such robots might help his IT business. Net-Tech currently uses courier services to rush laptops to customers who need them right away. “This could augment that,” Bratlien says. It is the essential source of information and ideas that make sense of a world in constant transformation The WIRED conversation illuminates how technology is changing every aspect of our lives—from culture to business The breakthroughs and innovations that we uncover lead to new ways of thinking the Governor’s Mansion is decorated for the holidays with a Sitka spruce tree from the Tongass National Forest. But Alaskans in the capital city aren’t just decking the halls with local greenery Listen now Cari Bowhay has worked through nearly 16 holiday seasons at Glacier Garden Nursery she thinks there’s something special about being here this time of year “It always smells like Christmas,” Bowhay said “It’s better than smelling like dirt the rest of the year and everybody seems to be 90 percent happier this time of year.” a variety of fir trees are leaned up against posts separated by type in different corrals These evergreens were barged up by the thousands from tree farms in Washington state Bowhay gestures to a Grand Fir that looks like a perfectly symmetrical cone “The tree farms definitely prune and shape all the trees to where they have that … nice tapered look,” Bowhay said Southeast Alaska has no shortage of trees growing outside. In fact, the City and Borough of Juneau and the Tongass National Forest allows people to harvest their own, within certain guidelines although you might poke yourself carrying it out of the woods But that classic-looking commercial Christmas tree presumably because it’s a little too cold for it,”  Brian Buma, an ecology professor at the University of Alaska Southeast There is a tree farm in Kodiak growing non-native Fraser firs But Buma says typically fir trees do well in places with dry It’s not exactly that they can’t handle the cold But access to sunlight and a long growing season is important for the tree’s competitive survival Buma says fir trees growing wild in Alaska isn’t out of the question “That’s something we’re actually thinking about,” Buma said “There’s things like silver fir that will presumably be moving north as the climate warms.” Silver firs have been spotted in parts of Southeast he says it can take decades for that type of tree to make a natural migration north “But the climate may be warming fast enough that people will start planting them in their yard far sooner you see them grow up naturally,” Buma said Buma says he likes the tradition of tromping through the woods and cutting down his own tree It’s a very sad looking spruce,” Buma said with a laugh “The only spot we can put it in our house is right in front of our heater.” Cari Bowhay says everyone has their own holiday tradition Hers includes buying fir trees barged up from Washington state “So we started coming here as a kid to get our Christmas tree “I get to enjoy the joy of seeing people coming in with their kids and bringing them in to see Santa and all that fun stuff.” Bowhay says spending time with family and friends — no matter where you get your tree — is what the holiday spirit is all about Find the right conifers to add beauty and structure to your landscape the most common conifer trees are pine trees but they belong to a different genus than blue pine Conifer trees are all perennially woody plants meaning they create a woody structure above-ground for their branches to grow on Most conifers bear cones that house the plant's seeds evergreens are plants that do not lose all their leaves or needles at once like deciduous trees and herbaceous plants Conifers are plants that house their seeds within cones (although some like yew and juniper look more like berries) Please enable JS and disable any ad blocker Caroline Donald visits the ancestral home of Clan Donald where the gardens are once again in safe hands and the historic trees will be given a boost with the planting of a new arboretum of endangered conifers When Andrew Peters first encountered the 40-acre gardens at Armadale Castle on the Sleat peninsula on Skye He found magnificent specimen trees from the 19th century as well as woodlands and exotic plants from across the globe But what made — and still makes — the place remarkable is not so much what is there but the fact that it is there at all on this rugged Hebridean island Tucked into a coastal pocket facing the mainland not only does the site benefit from the warm air of the Gulf Stream but it is protected by the lie of the land from the worst of the westerly winds ‘I love Armadale; it is pretty rare,’ says Mr Peters when the gardens were enjoying something of a heyday after the Clan Donald Lands Trust had stepped in to buy the castle and 22,000 acres of the once vast estate belonging to the Macdonald family just over a decade earlier such as montbretia and Rhododendron ponticum don’t wait for permission to take over and having watched the gardens slip into a genteel decline over the past 20 years or so Mr Peters spotted an advertisement for a ‘project gardener’ he saw it as a chance to re-energise them and make them worthy of international recognition He got the job and has been Armadale’s garden consultant since January 2019 Among his plans is a new arboretum that will be planted in existing woodland as part of the International Conifer Conservation Programme (ICCP) The project collects seeds of endangered species and grows them on to be replanted in various gardens so that there will be a resource from which to reintroduce them ‘We are getting about 140,’ says Mr Peters ‘together with 60 various plants from Chile Conifers already have a fine tradition here as the Victorian gardeners had the foresight to plant silver firs (Abies alba) as a shelterbelt; they now reach some 80ft or more and their distinctive forms can be spotted from 20 miles away tons of Irish topsoil were imported to make a comfortable home for specimen trees Mr Peters has not confirmed this was done for Armadale’s monkey puzzles Monterey cypruses and magnificent (now prostrate) Japanese cedar The castle itself — on the austere side and now a roofless ruin — was largely built on the site of an older house designed by James Gillespie Graham for the 2nd Baron Macdonald it is not that important; it was a badly built house of 1815 from the time following the Jacobite uprisings the product of the Anglicisation of the powerful Highland chiefs,’ admits Godfrey He is the 34th hereditary high chief of Clan Donald and talks on a bench overlooking the Sound of Sleat with dachshunds perched on his knees and those of his wife Having lived for many years at Kinloch Lodge on the estate Lord and Lady Macdonald have now passed the business on to their daughter but his great-grandfather Ronald was still in residence by the time Alexander married although ill for much of his life and not using the castle including the present Lord Macdonald’s grandfather were killed in the First World War (the fourth had died in the Boer War) and the estate was administered by trustees ‘so nobody really took the interest that was necessary in maintaining the fabric,’ explains Lord Macdonald We had peaches and grapes and other things a housekeeper would still draw the curtains Within three years of her retirement in the 1960s ‘Dry rot went through it like a dose of salts and that was the way it was when my father died in the 1970s,’ remembers Lord Macdonald Former clan chiefs may have enjoyed the benefits of an English education but that did not mean they learnt financial acumen ‘Looking back at the estate records of my father’s day it lost money every year.’ By the time the present Lord and Lady Macdonald took over ‘Due largely to death duties and other honourable debts the family had acquired over the years the bulk of the estate was sold.’ Encouraged by prominent members of the clan the couple packed their tartan outfits and set off for America to raise funds for a trust that was set up 50 years ago there is little to remind one that there was once a walled garden apart from a large clearing in the woodland and a hint of a wall Mr Peters has great plans for this space — once he has eradicated the Japanese knotweed it would be wonderful to reinstate it.’ Mr Peters also wants to make an online catalogue of all the trees we can start to communicate to Macdonalds right around the globe,’ he says he is determined to bring the gardens back to their former glory and beyond ‘I thought: “I am 61 years old; I promise to give them all my energy until I retire” — and that is what I am doing.’ Armadale Castle, Gardens and Museum of the Isles, Isle of Skye is open until November — see www.armadalecastle.com for details and times A 20% discount is on offer for visiting both Armadale and Attadale Their family histories are full of heads on spikes and villages being razed to the ground Bealach na Bà is as unforgettable and beautiful as it is nerve wracking Once essential elements of every brave Highlander’s armoury deadly dirks and sgian-dubhs provided protection against foes Nancy Mitford described the Highland games at Invertochie as ‘an extraordinary spectacle of apparently this delightful Borders castle was revived by bursts of sensitive restoration in the 19th and 20th centuries Dickies’ new Denim Trails collection combines authentic high-quality workwear in classic heritage styles with new bold fabric prints for a complete modern lifestyle The collection centres high quality materials that are both aesthetic and durable These classic staple pieces have been modernized while care has been given to maintain their original character with the inspiration of creating key timeless styles for men and women; a ‘Denim Uniform’ made using authentic 12 oz cotton denim enhanced with red stitch detailing souvenir style jersey garments and well-thought-out accessories This ‘uniform’ style features throughout the SS22 collection this season and makes reference to Dickies ‘100 uniform celebration’ in honour of Dickies’ 100 year anniversary this year and the many generations of workers the brand has stood alongside The collection has a deep colour palette with dark indigo for the denim pieces Garments throughout the range feature the Dickies script logo and a souvenir style embroidered design featuring a leopard and foliage graphic This collection’s key products include the Fort Lewis and Denim 100 pieces most notably the signature Fort Lewis Jacket made from 100% cotton twill and a bold interpretation of the Dickies heritage workwear jacket made for everyday use Other members of the Fort Lewis line include organic twill shirts tees (short and long-sleeved) and sweatshirts made from blue denim with contrasting ecru and red stitched reinforcements Other signature garments in this collection are the Silver Firs pieces crafted from organic cotton twill treated with a bold The key pieces of this sub-range include the Silver Firs Shirt the Silver Firs Short and the Silver Firs Pant the Silver Firs Shortall is the hero piece of the collection; a comfortable utility-inspired piece with a summertime aesthetic Accessories in this collection are bold and playful with the leopard print theme extending to a fluffy cotton towel Albertville AOP cap and Silver Firs Bucket hat – perfect for sunny beach days Denim Trails is a well-balanced collection of complimentary bold prints and timeless pieces that are comfortable functional and durable – a homage to Dickies’ rich history in workwear manufacture The Denim Trails Collection is available now from