Larouche C.,Direction de la recherche forestiere |
Gauthier M.-M.,Direction de la recherche forestiere |
Roy V.,Direction de la recherche forestiere |
Blouin D.,Center d'enseignement et de recherche en foresterie de Sainte Foy inc.
New Forests | Year: 2015
We established a long-term experiment in a temperate mixedwood stand to evaluate the effectiveness of silvicultural treatments in regenerating a mixed-species cohort while maintaining the dominance of conifers. Silvicultural treatments included clearcutting using careful logging around advanced growth (CLAAG), uniform shelterwood (US), group shelterwood with (GS-s) or without scarification (GS), and an uncut control (control). After 10 years, height and ground-line diameter growth responses of advanced balsam fir (Abies balsamea [L.] Mill.) regeneration were substantial in CLAAG and GS compared to the control, and intermediate in US. Growth responses were proportional to increases in canopy light transmittance resulting from harvest. Advanced balsam fir regeneration had low mortality (<10 %) and a high potential for release as measured by the apical dominance ratio. At the stand level, however, a shift in species composition occurred in the regenerating cohort. Over the 10-year period, composition changed from conifer-dominated to hardwood-dominated in CLAAG, GS, and GS-s compared to the control. Scarification increased the magnitude of this shift by favoring shade-intolerant hardwoods. Results highlight the need to find a balance between releasing advance conifer regeneration and limiting competition from less desirable species. © 2015, Springer Science+Business Media Dordrecht.
Issues and solutions for intensive plantation silviculture in a context of ecosystem management [Enjeux et solutions pour la sylviculture intensive de plantations dans un contexte daménagement écosystémique]
Barrette M.,Ministere des Forets |
Leblanc M.,Ministere des Forets |
Thiffault N.,Ministere des Forets |
Thiffault N.,Laval University |
And 10 more authors.
Forestry Chronicle | Year: 2014
Forest plantations are recognized as a silvicultural tool for ensuring a timber supply that meets public expectations regarding sustainable forest management. However, they are also part of the silvicultural scenario that shows the greatest potential for the artificialization of natural forests. From a firsthand perspective, intensive plantation silviculture objectives may appear antagonistic to those of ecosystem management. Here we describe the process through which we defined and documented plantation issues, then propose potential solutions to allow the integration of intensive plantation silviculture into ecosystem management. We identify issues related to the scale, localization and spatial arrangement of plantations, the key attributes and resilience of natural forests, social acceptability, and the productivity and profitability of plantations. We also propose potential solutions likely to help manage plantations within a context of ecosystem management. These include modulating silvicultural treatments to enhance the naturalness of plantations, conducting treatments to obtain expected production rates, and ensuring that plantations are deployed across the landscape in a manner that integrates stakeholder concerns and considers the naturalness of the forest matrix.
Suffice P.,University of Québec |
Suffice P.,Center denseignement et de recherche en foresterie de Sainte Foy Inc. |
Joanisse G.,Center denseignement et de recherche en foresterie de Sainte Foy Inc. |
Imbeau L.,University of Québec |
And 2 more authors.
Forest Ecology and Management | Year: 2015
Irregular shelterwood cutting has been recently prescribed to improve the regeneration of semi-tolerant species such as yellow birch (Betula alleghaniensis B.), while also maintaining the complexity of natural mixed forests. However, its effects on forest dynamics are poorly known. In this study, we document the short-term effects of three irregular shelterwood cutting patterns on the establishment and composition of regeneration as well as on its use by snowshoe hare (Lepus americanus E.). Specifically, we compared uniform, gap, and strip cutting patterns with soil preparation, relative to uncut controls. We counted seedlings, browse, and hare pellets, and measured habitat characteristics after two growing seasons in micro-plots delimited in each of the shelterwood cutting patterns. The mixture of soil and humus resulting from scarification promoted yellow birch establishment. Yellow birch seedlings in gaps were more abundant than in controls, but their abundance was comparable to other irregular shelterwood patterns. All irregular shelterwood patterns promoted competition mainly by pin cherry (Prunus pensylvanica L.f.), beaked hazel (Corylus cornuta M.), and mountain maple (Acer spicatum Lam.). Snowshoe hare browse on yellow birch was low for all irregular shelterwood patterns. Moose browse pressure was higher than that from hare. We found no short-term impact of the snowshoe hare on yellow birch seedling establishment and survival. Snowshoe hare pellet counts suggested a preference for gaps. This result could be explained by increased food and protective cover from higher seedling and shrub densities in gaps than in other treatments. In the short-term, up to three years post-treatment, irregular shelterwood cutting helps to promote yellow birch regeneration, a semi-tolerant species, while maintaining habitat for snowshoe hare. © 2015 Elsevier B.V.