Response of aspen stands to forest tent caterpillar defoliation and subsequent overstory mortality in northeastern Ontario, Canada
- 15 September 2010
- journal article
- Published by Elsevier BV in Forest Ecology and Management
- Vol. 260 (10), 1853-1860
- https://doi.org/10.1016/j.foreco.2010.08.032
Abstract
Overstory mortality, understory tree recruitment, and vegetation development were assessed in trembling aspen (Populus tremuloides Michx.) stands following two recent episodes of forest tent caterpillar defoliation (Malacosoma disstria Hbn.) in northeastern Ontario. The results suggest that poplar (aspen and balsam poplar (Populus balsamifera L.)) mortality increased with consecutive years of insect defoliation occurring from the mid-1980s to mid-2000s and the proportion of poplars in the overstory, but decreased with improved pre-defoliation tree vigour (DBH increment). The first outbreak, which lasted from the mid-1980s to early 1990s, was more severe in terms of insect defoliation and contributed more to poplar mortality and decline. The decline began in the late 1990s and peaked in early 2000s. Poplar regeneration and understory shrubs responded rapidly to foliage loss to insect defoliation and mortality of overstory poplars. The regenerated poplars were able to maintain their growth under developing shrubs and residual overstory canopy and numbers were sufficient to compensate for the poplar trees lost to insect infestation. The defoliation-induced overstory decline will accelerate the transition of aspen stands to conifer dominance through enhanced conifer recruitment and growth, and reduced hardwood overstory in aspen-dominated stands, while hardwood dominance will persist in pure aspen stands. From a timber supply perspective, the decline caused by forest tent caterpillar defoliation could delay the availability of aspen stands for harvesting by 40–50 years.Keywords
This publication has 22 references indexed in Scilit:
- Mountain maple and balsam fir early response to partial and clear-cut harvesting under aspen stands of northern QuebecCanadian Journal of Forest Research, 2004
- Predicting landscape patterns of aspen dieback: mechanisms and knowledge gapsCanadian Journal of Forest Research, 2004
- Testing forest ecosystem management in boreal mixedwoods of northwestern Quebec: initial response of aspen stands to different levels of harvestingCanadian Journal of Forest Research, 2004
- Dynamics of North American boreal mixedwoodsEnvironmental Reviews, 2002
- A review of the regeneration dynamics of North American boreal forest tree speciesCanadian Journal of Forest Research, 1999
- Decomposition of aspen, spruce, and pine boles on two sites in MinnesotaCanadian Journal of Forest Research, 1993
- Apical dominanceThe Botanical Review, 1991
- Carbon/Nutrient Balance of Boreal Plants in Relation to Vertebrate HerbivoryOikos, 1983
- Long-Term Effects of Defoliation of Aspen by the Forest Tent CaterpillarEcology, 1964
- Mortality of Overstory Trembling Aspen in Relation to Outbreaks of the Forest Tent Caterpillar and the Spruce BudwormEcology, 1958