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Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wood discoloration was investigated in 721 paper birch (Betula papyrifera Marsh.) trees from 146 sites across the managed forest of Quebec, Canada. Discoloration was present at breast height in 85% of trees, but its impact was limited in terms of tree basal area and volume, with proportions of 6.4% and 3.6%, respectively. These two measures were strongly correlated. Discoloration changed wood appearance but had no effect on microfibril angle and modulus of elasticity. Discolored wood was nevertheless denser, probably due to the accumulation of colored extractives. Predictive models were also developed and applied to 415 711 paper birch trees from 51 689 inventory plots across the province to study regional variation. Higher proportions of discolored basal area were obtained in the southwestern areas of the province where the climate is warmer and drier. In these areas, paper birch trees are larger and, likely, support bigger branches which can cause larger columns of discoloration when broken. Lower proportions were found in eastern regions where snowfall is more abundant. Smaller, more flexible branches in trees growing in these areas could explain this result. This study confirms the feasibility of large-scale mapping of wood discoloration in standing trees based on forest inventory and climate data. [ABSTRACT FROM AUTHOR]

Key Message: A model describing species composition, density and diameter distribution of saplings was developed from operational inventory data. It could be used as an input into growth models calibrated exclusively with merchantable trees to correct some recruitment bias. Important differences in distributions were found between plantations and naturally regenerated stands. Longer-term monitoring would be required to observe the effects of thinning treatments on saplings. Context: Saplings play important ecological and structural roles in forest stands. They also constitute the pool of candidate trees that are responsible for recruitment of merchantable sized trees. However, sapling information is often absent from regular inventory measurements (e.g. where no saplings are measured) even though they could be used as inputs in predicting recruitment in merchantable trees. Aims: The objectives were to develop models describing density and diameter distribution of saplings from operational inventories, e.g. having only merchantable tree inventory, and to evaluate how stand type (naturally regenerated stands and plantations) and various thinning treatments influence these distributions. Methods: Using data from both white spruce (Picea glauca [Moench] Voss) plantations and naturally regenerated balsam fir (Abies balsamea (L.) Mill.) stands having been commercially thinned, a zero-inflated poisson regression was used to model the stand density and a gamma regression to predict the two parameters of the Weibull used to characterize the diameter distribution. Results: Despite the fact that the operational inventory data is often limited (e.g. species, dbh, height), the accuracy of the models was good and unbiased. It could be integrated into growth models to complete missing sapling distributions and help to correct some recruitment bias. Important differences in species composition, density and diameter distribution were found between plantations and naturally regenerated stands, but only a moderate response in diameter distribution was observed with thinning treatments. Conclusion: These models will enable managers to estimate saplings in intermediate aged softwood forests of eastern Quebec using harvesting inventories or National Forest Inventory. Characterization of differences between plantations and naturally regenerated stands will be useful for integrating intensive plantation silviculture with ecosystem-based management. Longer-term follow-up would be needed to better evaluate the effects of thinning treatments. [ABSTRACT FROM AUTHOR]

White spruce breeding has traditionally focused on genetic improvement for high productivity, targeting mostly stem volume. However, new challenges, such as the effects of climate change on individual trees and ecosystems and the changing nature of forest products markets, require action to address these issues while providing improved stock for seed and seedling production. This work aims to define the relative importance of white spruce wood traits for the lumber industry, with the intent of guiding tree breeding programs. This manuscript examines: (1) wood features that are important for lumber, (2) the genetics of wood traits and their improvement and (3) the level of acceptance of raw material with optimal traits, as obtained from a survey conducted with sawmills. Stem diameter at stump height, wood density, bending strength and stiffness were determined as the most important properties for sawmills. Decay proportion, knot diameter, slope of grain and the proportion of compression wood were also determined as important for sawmills, but to a lesser extent. Breeding efforts aiming to produce lumber should focus on stems with improved growth that are capable of sustaining the production of dense wood in greater proportion. [ABSTRACT FROM AUTHOR]

The depleted state of the northern hardwood forests of Quebec, Canada has forced the hardwood flooring industry to adapt its production. American beech (Fagus grandifolia), a traditionally less desired species, is now increasingly being included in wood supplies to sawmills in western Quebec, where forest managers hope this resource can be valued before the onset of significant mortality and wood degradation from the beech bark disease. This study aimed: 1) to assess the preferences of consumers towards American beech flooring products compared to well known species traditionally used in this market; and 2) to compare results obtained in face-to-face surveys with web-based surveys of consumer preferences. Results from both survey types revealed that the finishing colour was the most important factor affecting the decision of respondents, followed by species and price. American beech ranked third in species preferences, just above birch. Divulgating species names only affected (positively) the perception of respondents towards oak. It was concluded that American beech could be included in the current wood flooring market, probably among cheaper options such as birch. The similarity of results from face-to-face and online surveys suggests that general trends in consumer preferences could be rapidly and cheaply assessed using the latter option. [ABSTRACT FROM AUTHOR]

Research Highlights: The spatial distribution of trees results from several ecological processes that can be difficult to measure. We applied a point process modelling approach that uses the diameter and species of neighbouring trees to represent inter-tree interactions through repulsive and attractive processes. Thinning treatments slightly influence the tree spatial distribution of trees in white spruce plantations. Integrating this "spatialiser" into growth models could help improve stand simulations following various thinning treatments over larger areas and longer periods. It could also allow for the use of spatially explicit models when tree position is not available. Background and Objectives: Tree spatial patterns result from several ecological processes and have important implications in forest ecology and management. The use of spatial information can significantly improve our understanding of forest structures. However, this implies intensive field work that is rarely integrated into forest inventories. The aims of this study were to develop a spatial distribution simulator of trees in white spruce plantations and to evaluate the influence of thinning treatments. Materials and Methods: A point process modelling approach was used to represent inter-tree interactions through repulsive and attractive process in white spruce (Picea glauca (Moench) Voss) plantations in eastern Quebec, Canada, that had been commercially thinned five years ago. Balsam fir (Abies balsamea (L.) Mill.) and hardwoods together can represent 30–40% of the basal area of these plantations. Results: The diameter and species of each tree's two closest neighbours were found to be the most important predictors in explaining the observed distances between trees. Despite the short period since thinning treatments, results showed that the treatment had slight significant effects on tree interactions. However, their impact on the global spatial distribution of stands is quite limited. Conclusions: Using only a few readily-available variables (species and diameter of trees), this "spatialiser" will make it possible to assign spatial coordinates to trees and generate realistic stand spatial structures even after various silvicultural treatments. [ABSTRACT FROM AUTHOR]