Hugues Power

• Ph.D.
• Researcher at Government of Quebec

Precommercial thinning reduces the density of young, high-density stands, promoting the growth of selected trees. However, existing growth models are calibrated for merchantable-sized trees and do not account for saplings, which limits their ability to simulate the changes induced by precommercial thinning. To address this gap, we developed EsPaCe,...

Background tree mortality can be defined as the death of trees that naturally occurs as stands develop, in the absence of major or sudden stand disturbances. The phenomenon is often linked to ontogeny and competition and generally affects individual trees, unlike catastrophic mortality, which affects most trees in the stand. To forecast stand chara...

Repeated diameter-limit cutting in mixedwood forests often leads to altered stand composition, quality, and regeneration, hence decreasing productivity and value over time. We studied the evolution of stand characteristics after diameter-limit cutting on a 15-year period, beginning from 11 to 43 years after cutting. We used 415 sample plots (200 m²...

Dans combien d’années sera-t-il possible d’effectuer la prochaine récolte dans un scénario de coupes partielles successives? Voici une information importante pour les aménagistes pratiquant des coupes partielles en forêt mixte tempérée. Pour obtenir un même volume lors de la prochaine récolte, le temps de rotation varie notamment selon l’intensité...

[English will follow] De 1995 à 1999, un réseau de suivi provincial a été établi pour mesurer les effets réels des coupes de jardinage exécutées dans les forêts du domaine de l’État. L’objectif était de vérifier si les hypothèses énoncées dans le Manuel d’aménagement forestier (MAF) relatives à la production se confirmeraient à la suite de l’applic...

Tree functional diversity can increase forest productivity by enhancing species interactions and providing greater growth stability. However, very few studies have examined the influence of tree community trait structure on survivor growth, recruitment and mortality simultaneously, which are the main drivers of forest population dynamics. Here, we...

Commercial thinning is a silvicultural treatment that has been practiced for centuries in Europe. However, in Eastern Canada, its application to naturally regenerated stands is much more recent, and long-term monitoring of this treatment realized in an operational context is rare. We monitored 135 paired sample plots (thinned and control) over a 20...

Since the mid 1990s, partial cuts have been widely used in yellow birch–conifer stands (BJR, bétulaies jaunes résineuses) in the temperate forests of Québec. We studied the impact of residual basal area on stand composition and on the time required to reconstitute enough merchantable basal area to allow for a second partial cut, according to the us...

Depuis plusieurs années, les coupes partielles sont utilisées dans les peuplements mixtes tempérés pour récolter périodiquement un volume de bois de qualité, tout en contribuant à l’établissement et à la croissance de la régénération d’essences désirées. L’atteinte de ces objectifs nécessite que la régénération préétablie contribue à remplacer le v...

Dans un contexte d’aménagement forestier durable, il est important de prévoir comment la régénération préétablie peut contribuer à remplacer la surface terrière et le volume marchand des arbres récoltés par coupes partielles en forêt mixte. Cependant, les connaissances qui permettent d’estimer la contribution des gaules à la surface terrière marcha...

Since the mid 1990s, partial cuts have been widely used in yellow birch–conifer stands (BJR, bétulaies jaunes résineuses) in the temperate forests of Québec. We studied the impact of residual basal area on stand composition and on the time required to reconstitute enough merchantable basal area to allow for a second partial cut, according to the us...

Tree recruitment is affected by numerous biotic and abiotic factors, including climate. However, the relative importance of climate variables in empirical models of tree recruitment remains to be evaluated. We fitted models of tree recruitment to 26 species in the province of Quebec, Canada. For a better understanding of the recruitment process, we...

Saplings (tree species whose diameter at breast height ranges from 1.1 to 9.0 cm) are important in forest growth and development. Their abundance and density can lead to specific forest successional trajectories and ecosystem characteristics. Yet, the consideration of saplings in forest management planning is a relatively new topic and is still rar...

Réaliser un diagnostic sylvicole complet en vue d’un traitement sylvicole requiert généralement que l’état de la régénération soit évalué à l’aide d’un inventaire par échantillonnage, particulièrement pour les peuplements dominés par l’érable à sucre (Acer saccharum Marsh.) ou le bouleau jaune (Betula alleghaniensis Britt.), dans lesquels les coupe...

Performing a complete silvicultural diagnosis before a silvicultural treatment generally requires assessing the state of regeneration with the help of an inventory by sampling, particularly for stands dominated by sugar maple (Acer saccharum Marsh.) or yellow birch (Betula alleghaniensis Britt.), in which partial cuts are recommended. This inventor...

Depuis le milieu des années 1990, des coupes partielles sont utilisées de manière généralisée dans les bétulaies jaunes résineuses (BJR) de la forêt tempérée du Québec. Nous avons étudié l’effet de la surface terrière résiduelle sur la composition du peuplement et sur le temps nécessaire pour reconstituer une surface terrière marchande permettant g...

Le modèle de croissance Artémis-2014 est utilisé pour le calcul des possibilités forestières et, lorsqu’il est jumelé au modèle d’évaluation de la rentabilité des investissements sylvicoles (Méris), pour les analyses de rentabilité économique. Sa plus récente mise à jour incorpore des mesures supplémentaires provenant de placettes échantillons perm...

Individual tree recruitment is an important element needed to understand stand dynamics, as it influences both stand composition and productivity. Forest growth simulators usually include recruitment models. The quality of recruitment predictions can have long-term impacts on estimations of forest growth, ecosystem health and the commercial utility...

The temperate mixedwood forests of eastern North America have been managed by partial cutting for several decades. To ensure that regeneration contributes to replacing the commercial-size stems that are removed by partial cutting, forest managers need to anticipate how saplings (i.e., regenerating trees with a diameter at breast height >1.0 cm) dev...

Le modèle de croissance par tige individuelle Artémis est utilisé pour prévoir l’évolution de placettes-échantillons lors des calculs de possibilité forestière ou des analyses de rentabilité économique. D’abord diffusé en 2009, il a été revu en 2014 (Artémis 2014 version 3.0.6) pour intégrer plus de mesures dans ses données de calibration. Afin de...

New silvicultural practices to meet the requirements of ecosystem-based forest management are being adopted operationally, even if the long-term outcomes remain unknown. In eastern Quebec, Canada, the conversion of plantations from even-aged to irregular or uneven-aged stands is being carried out in 10% of commercial thinning operations. Existing g...

Forest growth models are essential for forest management and the elaboration of forest policies. For model users, assessing the performance and the reliability of a model is essential. Hence, validation is an important step of model development. However, species-specific and observation year-related patterns in model error are rarely reported, alth...

Pour les utilisateurs, l’évaluation des performances et de la fiabilité d’un modèle de croissance est essentielle. Cependant, les biais spécifiques à l’espèce et à l’année d’observation sont rarement signalés, bien que des changements dans les conditions de croissance soient susceptibles d’augmenter la présence de tels biais dans les modèles. Dans...

Au cours des années 1970 et 1980, les forêts mixtes ont souvent fait l’objet de coupes à diamètre limite. Lors de ces interventions, la récolte des tiges de meilleure qualité était souvent effectué, laissant des peuplements résiduels dégradés dans lesquels les espèces non commerciales abondent alors que les tiges résiduelles d’essences désirées son...

Au cours des années futures, les changements climatiques modifieront les conditions de croissance des peuplements forestiers. La planification des activités d’aménagement forestier, y compris le calcul des possibilités forestières, doit en tenir compte. Pour ce faire, les courbes qui prévoient l’évolution dans le temps du volume produit par les peu...

Harvesting practices in temperate mixedwoods of eastern North America have a history of diameter-limit cuts, which have often resulted in degraded residual stands. In this study, we examined the factors influencing stand basal area (BA) and tree diameter growth in previously high-graded mixedwood forests, to understand which stands are more likely...

Multinomial équations were parameterized to estimate initial stem quality and its evolution over time for the main broadleaf tree species of Québec, Canada.

La qualité des tiges feuillues est un élément particulièrement important à considérer lors de la planification de l'aménagement forestier puisqu'elle est directement liée à la qualité et à la valeur des billes et des produits transformés qui en découlent. La qualité des arbres étant influencée par la dimension des tiges et leur milieu de croissance...

During the past decades, many growth models have been developed that can now be applied over large parts of Québec's forest. For the user, choosing the right model for a given territory of interest can be challenging. The present study aims to compare two forest growth models which can be used over most of Québec's commercial forest: Artémis, a tre...

Le phénomène du déclin de l’érable à sucre jumelé à celui de la prolifération du hêtre à grandes feuilles dans les érablières soulève de nombreuses questions et inquiète les aménagistes. En réponse à ce besoin de connaissances, la Direction de la recherche forestière du ministère des Forêts, de la Faune et des Parcs du Québec a constitué un comité...

Long-term success of forest management requires knowledge of standing tree characteristics and, an estimation of their evolution over time. In this study, hardwood stem quality was assessed using a specifically designed, non-destructive quality classification system that comprises four categorical output classes based on stem size and occurrence of...

Over the last two decades, patch cutting systems have been applied in Eastern Canada to regenerate uneven-aged yellow birch (Betula alleghaniensis Britton)-conifer stands. Yet, we still know very little about how the trees located in the between-patch matrix respond to treatments. This study compares growth, recruitment, and tree mortality of yello...

Most models of modulus of elasticity (MOE) and modulus of rupture (MOR) use classical dendrometric variables and do not use crown characteristics that are known to influence wood formation and properties. The objective of this study was to evaluate the benefit of including crown variables in black spruce MOE and MOR models. Values of MOE and MOR we...

For many years, forest growth models have been essential tools for managers wishing to predict stand growth. In Quebec (Canada), a tree-level forest growth simulator called Artémis was developed in 2009 by the provincial forest research department (Direction de la recherche forestière, Ministère des Forêts, de la Faune et des Parcs) to calculate an...

Maple syrup production is an important economic activity in north-eastern North-America. The beginning and length of the production season is linked to daily variation in temperature. There are increasing concerns about the potential impact of climatic change on this industry. Here, we used weekly data of syrup yield for the 1999-2011 period from 1...

Description of climate variables used in the construction of statistical models. (DOCX)

The foliage biomass–sapwood relationship (the pipe model) is critical for tree growth and is used in tree growth models for understanding the implications of this structural relationship on the allocation of resources. In this research, we compared this relationship for two commercially important and sympatric species, black spruce (Picea mariana (...

Key message Growth conditions related to inter-tree competition greatly influence black and white spruce foliage biomass and projected leaf area characteristics. Abstract Foliage characteristics such as biomass and area are important among other reasons because they can be related to tree growth. Despite their economic and ecologic importance, equa...

Black spruce (Picea mariana (Mill.) Britton, Sterns & Poggenb.) and white spruce (Picea glauca (Moench) Voss) are phylogenetically proximal species that differ in productivity. Crown characteristics of these two species have not been extensively studied, in spite of the importance of these two species to the Canadian boreal forest and the importanc...