Global change requires us to reframe the reference conditions underpinning ecosystem management. It has altered the resilience of the pre-industrial forest, driving its gradual transition toward novel forest ecosystems. Ecosystem management aimed at reducing the gaps between managed and natural forests will remain relevant to promote biodiversity, resilience and the sustainability of forest management, provided that our reference conditions are adapted to this transition. Management today needs a reference that tracks where the forest currently sits between past and projected conditions, i.e., the contemporary natural forest. This reference is neither the natural forest of the past nor that of the future but defined both by pre-industrial attributes that remain relevant and by projections of likely future states. We seek to characterize the novel natural disturbance dynamics and emergent successional trajectories to determine the variability of its key attributes. To operationalize this perspective, we propose using the successional trajectories of managed forests as a monitoring indicator of their resilience. Defining the contemporary natural forest will also allow us to adapt silviculture to enhance resistance, maintain resilience and facilitate transition. To manage the uncertainty associated with global change, this approach should be embedded within a framework of adaptive management.
Les changements globaux nous obligent à redéfinir les conditions de référence qui sous-tendent l’aménagement écosystémique. Ils ont altéré la résilience de la forêt préindustrielle, entraînant sa transition graduelle vers de nouveaux écosystèmes forestiers. L’aménagement écosystémique visant à réduire les écarts entre forêts aménagées et naturelles demeurera pertinent pour favoriser la biodiversité, la résilience et la durabilité de l’aménagement forestier, à condition que sa référence soit adaptée à cette transition. L’aménagement a aujourd’hui besoin d’une référence qui situe la forêt entre les conditions passées et projetées, i.e., la forêt naturelle contemporaine. Cette référence n’ est ni la forêt naturelle du passé ni celle du futur, mais se définit par des attributs préindustriels toujours pertinents et par des projections d’états futurs probables. Nous cherchons à caractériser les nouvelles dynamiques de perturbations naturelles et les trajectoires successionnelles émergentes pour déterminer la variabilité de ses attributs clés. Pour rendre cette perspective opérationnelle, nous proposons d’utiliser les trajectoires successionnelles des forêts aménagées comme indicateur de suivi de leur résilience. La définir permettra aussi d’adapter la sylviculture pour accroître la résistance, maintenir la résilience et faciliter la transition. Pour composer avec l’incertitude associée aux changements globaux, cette approche devrait s’inscrire dans un cadre de gestion adaptative.
Canada’s forest sector must maintain wood supply, carbon storage, biodiversity, and social values as climate change and other global stressors increase the risk of disturbance and threaten forest resilience. Climate-Smart Forestry (CSF) offers an important framework for integrating adaptation, mitigation, and socio-economic objectives, but practitioners often lack spatial decision support tools that connect stand-level actions to landscape-scale resilience under uncertain future conditions. We introduce DIVERSE, a pan-Canadian research partnership working across 22 managed-forest landscapes (>20 Mha) to implement and test the Functional Complex Network (FCN) approach as a spatially explicit, resilience-oriented planning method aligned with CSF. FCN represents landscapes as networks of stands and combines functional trait diversity and redundancy with network properties, including connectivity, centrality, and modularity, to identify where diversification, conservation, or spatial reconfiguration can enhance resilience while limiting ecosystem-wide risk. We summarize DIVERSE’s six integrated research themes and operational products: (1) vulnerability and trait baselines; (2) climate-adaptation guidance for species and seed sources; (3) FCN-based resilience assessment and prioritization; (4) climate and management scenario testing through landscape simulation; (5) socio-economic feasibility analyses; and (6) operational field experiments. DIVERSE will evaluate where and when FCN can improve the robustness of forest management in Canada and support the long-term sustainability of future Canadian forests.
AI (artificial intelligence) burst upon the scene a couple of years ago. Its pace of development has moved exceedingly rapidly, leading to widespread application, as well as generating concerns about where it all leads. This article focuses on the former, and in particular on the remarkable ability that AI has in generating computer code. The article attempts to demonstrate that ability by having ChatGPT’s Codex coding agent program solutions for two well-known forestry problems – simple point sample forest inventory compilation and the much more complex wood supply modelling. In step-by-step fashion, the article describes building functional Java language solutions for these two problems, using Unix on a Macintosh computer. The article notes that while using the Codex agent is not for the digitally challenged, it nonetheless does not require coding experience. The article demonstrates that Codex, and similar coding agents, offer incredible application opportunities in forestry. The article wonders if our forestry professionals and our forestry schools are attuned.
L’intensification et la diversification des usages du territoire soulèvent des enjeux environnementaux, économiques et sociaux croissants dans l’Est du Canada. Cette étude évalue les transformations territoriales et les conflits d’usage des terres dans la Péninsule acadienne (Nouveau-Brunswick) sur une période de 40 ans (1985–2025). L’objectif principal était de quantifier les changements d’occupation du sol et d’identifier les principaux moteurs anthropiques de ces mutations. En utilisant des séries chronologiques Landsat et Sentinel-2 traitées via l’algorithme Random Forest, la recherche a analysé un territoire de 167 100 hectares, incluant l’ancien champ de tir de Tracadie, avec une précision globale avoisinant 90 %. Les résultats révèlent une période de déboisement initial suivi d’une régénération (1985–2015), puis une expansion agricole rapide à partir de 2015. Globalement, le couvert forestier est passé de 81 % à 73 %, tandis que les terres agricoles ont progressé de 15 % à 23 %. Cette dynamique représente un gain net de plus de 14 200 hectares pour l’agriculture au détriment de la forêt acadienne, portant la superficie agricole totale à plus de 39 000 hectares en 2025. Cette expansion récente illustre la pression croissante exercée sur les massifs forestiers du secteur et expose les défis majeurs d’aménagement du territoire dans la Péninsule acadienne.
Thinning strategies based on release of individual crop trees sacrifice some Dominant trees to provide prescribed growing space. This study uses increment cores to reconstruct early growth and post-thinning response of Dominant, Codominant, and Intermediate white spruce released on two, three, or four sides. Three stands planted in the 1990s were commercially thinned in the winter of 2017/18, during the 2017–2021 drought period. Analysis of covariance was used to assess drought resistance in 2018, growth release relative to prior basal area increment, and absolute 5-year basal area increment, controlling for 2017 diameter. Intermediate trees showed significantly lower drought resistance and growth release with a 3-sided vs. 2-sided release, though resistance scores were all greater than 1.0. Dominant trees maintained stable resistance and growth release across thinning intensities. Years to breast height and diameter in 2008 were significantly different between crown classes and had strong, positive relationships with post-thinning basal area increment. Results suggest low thinning to the same residual stocking will avoid shock to Intermediate trees while maintaining the high growth potential of Dominant and Codominant trees, warranting further study to assess duration of the effect across a range of residual stocking.
This study examines the dynamics of Abies religiosa (Kunth) Schltdl. & Cham. decline in the Monarch Butterfly Biosphere Reserve (MBBR) of Mexico, and its relationship with climate change, using remote sensing data acquired by unmanned aerial vehicles (UAVs), also named drones. Carried out between April and October 2023 over a 25 ha area within the MBBR core zone, this study integrated LiDAR and multispectral imagery to detect and geolocate individual trees, assigning vitality classes based on the normalized difference vegetation index (NDVI). We also introduced a new metric, the Monthly Dryness Index (MDI), which combines temperature and precipitation to capture short-term fluctuations in dryness conditions and evaluate their influence on tree vigour. The results indicate a statistically significant decline in NDVI values in June 2023, coinciding with an increased MDI of 0.47 together with a +2.7°C heat wave anomaly, suggesting an extreme drought event. A transition in tree vigour was observed, with the proportion of healthy individuals decreasing from 37% in May to 18% in June, and weakened trees increasing from 56% to 72%, indicating a critical shift in stand health. Regression models showed that MDI effectively explained variations in the number of trees by vitality class, with consistently high coefficients of determination ( R² ≥ 0.94) across vitality classes (healty, weakened, highly weakened, and dead trees), highlighting the species’ vulnerability to heat waves during the dry season.
We evaluated the long-term effects of greenhouse inoculation with native ectomycorrhizal fungi on the survival and growth of planted jack pine ( Pinus banksiana) and black spruce ( Picea mariana) in boreal Ontario, Canada. Between 1997 and 1999, operational plantations were established with inoculated (IC) and non-inoculated (NI) seedlings, and we reassessed ten paired trials 20 to 25 years later. We evaluated both stand-level (i.e., tree density, basal area, and gross total volume) and individual-tree attributes (i.e., total height and QMD) across 195 fixed-area (200 m 2 ) plots (96 – IC, 99 – NI) and compared responses between species and treatments. Jack pine plantations inoculated with Hebeloma spp., established on dry, nutrient poor sites, showed sustained stand-level advantages, with significantly higher crop tree density (+17%), basal area (+26%), and gross total volume (+29%) relative to the NI controls. Inoculated jack pine blocks also supported fewer deciduous competitors, contributing to greater wood volume accumulation. In contrast, black spruce plantations, established on more nutrient rich, mesic sites, displayed modest and non-significant increases in stand-level metrics (+12–13%), alongside higher ingress of non-crop conifers such as balsam fir ( Abies balsamea). For both species, quadratic mean diameter and height did not differ between treatments, indicating that benefits arose from enhanced early survival rather than accelerated growth in inoculated individuals. Our results demonstrate that inoculation can improve long-term plantation performance on dry, nutrient-poor sites, commonly planted with jack pine, while responses on mesic sites, more commonly planted with black spruce, remain variable and context-dependent.
Effective forest management in the context of climate change requires adaptive approaches. One key strategy is increasing diversity to mitigate the associated risks. This study employs a functional approach to assess the diversity of the Monteregian forest (Canada) and provides management recommendations aimed at enhancing resilience. We integrated data from both already established tree species and species projected to migrate northward due to climate change. Using hierarchical clustering based on key functional traits—leaf nitrogen, specific leaf area, seed mass, and wood density—we identified functional groups that capture the ecological diversity of the region’s species pool (present and potential). Further, a cluster analysis from over 19 000 inventories identified recurrent forest types. Groups were not represented equally, thus reducing potential response to future risks. It would be advisable to prioritize some groups, through management or planting, to increase regional diversity. Our findings underscore the usefulness of functional diversity, advocating for forest management practices that foster a resilient and diverse forest community. The study’s recommendations provide actionable insights for foresters, emphasizing the need for strategic selection and conservation efforts to future-proof forests. The method can be easily adapted to other forest types and species pools.
Agroforestry systems (AFS) provide several benefits within agroecosystems. We sought to learn more about the perceptions of Quebec farmers practicing agroforestry, in order to compare their initial motivations with the perceived benefits and challenges encountered. To do this, we used the values of nature framework. Semi-structured interviews were conducted with a sample of 28 farmers in Quebec who had been implementing AFS for at least five years. Most of benefits mentioned are associated with non-economic instrumental values (e.g., wind control), and to a lesser extent, intrinsic (e.g., biodiversity) and relational (e.g., aesthetic appeal of the AFS) values. The challenges are primarily related to relational values, particularly maintenance, which requires resources largely provided by the farmers themselves, in a form of environmental stewardship, while agroforestry systems (AFS) offer ecological services that benefit the entire community. To overcome these challenges, farmers have proposed improvements that could be implemented by government authorities (e.g., tending subsidies, payments for ecosystem services) and by agroforestry advisors (e.g., dissemination of examples). Our results highlight that current government programs supporting AFS remain limited in their capacity to encourage greater adoption of these systems or their sustainability, as the success of AFS still largely depends on the value placed on them by farmers.
We used the forest carbon budget model FORCARB-ON2 to project carbon stocks in a forest ecosystem and harvested wood products (HWP) in the six ecoregions of Ontario’s managed forests. Carbon stock levels were predicted from 2021–2100 for three management scenarios with a constant harvesting level throughout the simulation horizon and for two natural development scenarios. Harvesting levels in three management scenarios reflected actual harvest volumes from 2011–2020 and 2001–2020 and planned harvest volumes (i.e., maximum harvest volume allowed in forest management plans) from 2011–2020. Natural development scenarios assumed no harvesting and either pre-suppression era or modern natural disturbance cycles. The results indicate that keeping harvest volumes at the historical levels (either 2011– 2020 or 2001–2020) would increase carbon stocks in forests and HWP by the end of the century. However, increasing harvesting to the maximum planned level would reduce stocks in both forest and combined forest–HWP pools. The analyzed management scenarios suggest there is room to increase harvest volumes to a level between historical and maximum planned, while maintaining various carbon stock indicators at 2021 levels. The results assume that forest growth, successional changes, and natural disturbance remain constant throughout this century. Changes to the above rates caused by climate change or widespread natural disturbances would affect future forest conditions and may alter predicted forest carbon stocks.
Black spruce breeding zones (BZs) in northwestern Ontario, Canada, were assessed for the feasibilities of expanding superior tree selection and orchard seed deployment across existing BZ boundaries under climate change. The assessment was based on performances of open-pollinated families in progeny tests established in four second-generation BZs. In these tests, families from outside BZs were tested alongside with families from within BZs. Results showed that trees grew faster with higher survival rates in southerly BZs than in northerly BZs. Within a BZ, families from southern BZs were taller, but with slightly lower survival rates in northerly BZs, while families from northern BZs were shorter with comparable survival in southern BZs. These patterns were consistent with results from provenance studies, suggesting potential benefits from deploying orchard seeds from southern BZs more northwardly, provided slightly lower survival rates not serious concerns. Genetic worth of breeding populations for the next generation could be improved by 4.6% in height when the top 100 genetically superior trees were selected with families within BZs. Allowing selection to include families from southerly BZs could lead to an average improvement of 4.9%. The implications for black spruce tree improvement programs are discussed.
Adaptive silviculture hinges on our capacity to predict future changes in tree species demography (e.g. growth, mortality) in response to climate change. Experimental tree translocation studies across climate gradients can help anticipate such changes. The TransX experiment is a network of provenance trials, ranging from North Carolina (US) to Quebec (CA), where populations of ten boreal and temperate tree species, and genetically improved genotypes of four commercially important tree species have been planted simultaneously and will be monitored for their response to gradients of 14.5°C in mean annual temperature and 600 mm in precipitation. The objectives of this experiment are to: 1) quantify the effect of climate on trait variation and plasticity across selected tree populations and species, and 2) assess how such trait variation relates to growth and survival. Here we outline the design of the experiment, and describe the research efforts to monitor annual survival, health, growth, leaf morphology and physiology, and track leaf phenology using time-lapse cameras. By exposing major tree species to a wide range of climate and site conditions, the TransX project will fill significant knowledge gaps on forest ecosystem responses to climate change and inform adaptive management strategies, such as forest assisted migration.
Les systèmes agroforestiers (SAF) procurent plusieurs bénéfices au sein des agroécosystèmes. Nous avons voulu en savoir davantage sur les perceptions des agriculteurs québécois pratiquant l’agroforesterie, afin de comparer leurs motivations initiales avec les bénéfices perçus et les défis rencontrés. Pour ce faire, nous avons mobilisé le cadre des valeurs accordées à la nature (values of nature). Des entretiens semi-dirigés ont été réalisés auprès d’un échantillon de 28 agriculteurs au Québec ayant implanté des SAF depuis au moins cinq ans. La majorité des bénéfices mentionnés sont associés aux valeurs instrumentales non économiques (p. ex. contrôle du vent), et dans une moindre mesure, intrinsèques (p. ex. biodiversité) et relationnelles (p. ex. beauté des SAF). Les défis sont liés principalement aux valeurs relationnelles, avec notamment l’entretien qui nécessite des ressources devant être largement fournies par les agriculteurs eux-mêmes, dans une forme d’intendance environnementale (stewardship), alors que les SAF offrent des services écologiques qui bénéficient à l’ensemble de la collectivité. Pour dépasser ces défis, les agriculteurs ont proposé des améliorations pouvant être mises en place par les autorités gouvernementales (p. ex. aide à l’entretien, paiements pour services écosystémiques), et par les conseillers en agroforesterie (p. ex. diffusion de bonnes pratiques). Nos résultats soulignent qu’actuellement, les programmes gouvernementaux de soutien aux SAF demeurent limités dans leur capacité à encourager une adoption plus importante de ces systèmes ou leur pérennisation, les succès des SAF reposant encore largement sur la valeur qui leur est accordée par les agriculteurs.
An experiment was established in 1986 near Dégelis in Québec, Canada, to measure the effects of initial planting density and commercial thinning combined with pruning on the wood quality and growth of black spruce (Picea mariana (Mill.) B.S.P.). A total of 8 levels of initial planting density ranging from 1111 stems/ha to 4444 stems/ha were compared. Except in control (unthinned) plots, commercial thinning from below was then carried out when basal area reached 28 m2/ha in each level of planting density. Analyses of variance were performed using generalized linear mixed models (GLMMs). Results show that black spruce wood quality was not affected by commercial thinning combined with pruning, but that it was closely linked to initial planting density. Growth variables were affected by both initial planting density and thinning scenario. Commercial thinning substantially reduced mortality rate, with thinned plots reaching a level 4.5 times lower than in unthinned plantations.
Canada is a forest nation. Its forests are spatially extensive, ecologically diverse, and of global importance. While national-level forest statistics are used for international reporting and comparison, they often fail to reflect the distinctive structure and stewardship context of Canada’s forest estate, which includes millions of hectares of remote, unmanaged forests alongside actively managed zones governed by provincial and territorial stewardship frameworks. In managed areas, harvesting levels are regulated, and regeneration, either through replanting or natural processes, is a legislated requirement. This coexistence of managed and unmanaged forests complicates interpretation of national statistics and can lead to mischaracterizations of forest conditions and management practices, both within Canada and abroad. This communication explores the challenges of comparing national forest statistics in a global context, using Canada as a case study. We highlight how Canada’s large geographic extent, variation in management intensity, and the coexistence of managed and unmanaged forest zones complicate cross-country comparisons, and in turn reinforce the value of forest assessments that emphasize core traits and directly measured attributes over derived or qualitative metrics.
Cet article est le quatrième d’une série qui analyse les enjeux contemporains en forêt tempérée au Québec. Nous y abordons plus précisément les changements climatiques en traçant d’abord un bref portrait du climat historique ainsi que de ses changements contemporains et anticipés. Nous discutons ensuite de leurs principaux impacts sur les écosystèmes forestiers, de même que des enjeux qui en découlent. De nombreuses études révèlent que depuis le milieu des années 1970, la hausse rapide des températures a des répercussions sur les écosystèmes forestiers, notamment sur la composition et la productivité des forêts, le régime de perturbations naturelles, le cycle biogéochimique des éléments, les populations fauniques et la production acéricole. Malgré tout, nous n’avons pas relevé de grands enjeux pour les 3 principales essences de la zone tempérée nordique du Québec (soit l’érable à sucre [Acer saccharum Marsh.], l’érable rouge [Acer rubrum L.] et le bouleau jaune [Betula alleghaniensis Britt.]) en lien avec les changements climatiques anticipés d’ici la fin du siècle. En effet, le climat de la zone actuelle est susceptible de demeurer à l’intérieur des conditions généralement rencontrées dans l’aire de répartition de ces espèces. De même, on ne semble pas anticiper de grands changements au régime de perturbations naturelles dans cette zone. Nous identifions néanmoins certains enjeux socioéconomiques et écologiques d’importance qui découlent des impacts des changements climatiques sur les écosystèmes forestiers.
Trees with poor stem form significantly reduce lumber recovery but the incidence of defects in managed stands is rarely translated into operational timber volume impacts. We assessed over 5 600 conifer trees in stands aged 20-40 years in central British Columbia (BC), Canada. We recorded the species, height and DBH of trees and the height of defects including forks, crooks, broken tops and stem infections of western gall rust (Cronartium harknessii) and atropellis canker (Atropellis piniphila). We queried local sawmills for their sawlog specifications and applied simplified versions of them to our sample trees in situ. We compared the sawlog volume of reference trees with the same measurements but without defects, to the actual sawlog volume after defective portions were removed, at log lengths of 3-7 m, 3 m being the minimum acceptable and 7 m, the preferred. Lodgepole pine (Pinus contorta var. latifolia) suffered significantly greater loss of potential sawlog volume proportionately than interior spruce (Picea glauca X P. engelmannii) and subalpine fir (Abies lasiocarpa). In mid-rotation lodgepole pine plantations, the impact of combined defects approached 20% of current potential sawlog volume at the preferred length of 7 m, with implications for commercial thinning opportunities and future sawlog-focused timber supply.
This paper is the fourth in a series on the topic of contemporary issues in Québec’s temperate forest. It focuses on the topic of climate change, beginning with a brief profile of climate history and changes, both contemporary and anticipated. It goes on to discuss the main impacts of climate change on forest ecosystems and the issues raised. Many studies have shown that rapidly rising temperatures since the mid-1970s have affected various aspects of forest ecosystems, including forest composition and productivity, natural disturbance regimes, the biogeochemical cycling of elements, wildlife populations and maple syrup production. Despite this, however, no major issues were identified for the three principal tree species in Québec’s northern temperate zone (i.e., sugar maple [Acer saccharum Marsh.], red maple [Acer rubrum L.] and yellow birch [Betula alleghaniensis Britt.]) as a result of anticipated climate change between now and the end of the century. The climate in the current temperate zone is likely to remain within the conditions generally encountered in these species’ range. Similarly, the natural disturbance regime in the zone is not expected to change significantly. However, we did identify some important socioeconomic and ecological issues arising from the impacts of climate change on forest ecosystems.
Here we return 24 years post-establishment to 30, one hectare stem-mapped plots initially installed in ≈ 20-year-old lodgepole pine (Pinus contorta var. latifolia) leading stands, in the central interior of British Columbia (BC), Canada. We use unmanned aerial vehicle (UAV) imagery and ground verification plots to estimate current volumes and compare this to forecasts based on initial plot conditions. Our results highlight the increasing level of uncertainty associated with forecasts of stand growth under changing environmental conditions and reaffirm the need for ongoing monitoring at multiple scales to capture unforeseen increases and decreases in stand productivity. At establishment, 74% of lodgepole pine trees were healthy, while 24 years later, only 56% remain so and although comandra blister rust (Cronartium comandrae) was the leading cause of mortality, a variety of biotic and abiotic damage agents compromised potential sawlog volume. Estimates of Site Index (SI) also changed considerably over the 24-year-period with 1/3 of the stands experiencing an increase of three metres or more. When we benchmarked growth and yield forecasts from the model TASS III v. 4.1.3.7 against UAV derived total volume estimates, only with updated SI estimates and revised rust mortality scenarios did the model accurately forecast current productivity.
