PARENT SESSION
Poster Session 2: Forest Ecology
Monday, August 8, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal
Enrichment of degraded early-successional forests : analysis of a six year experiment in north-eastern North America.
Paquette, Alain1, Bouchard, André1, Cogliastro, Alain1, 1 Institut de recherche en biologie végétale;, Montréal, Québec, Canada
ABSTRACT- New forestry practices are being proposed or revisited throughout the world as natural regeneration of disturbed stands in rural communities likely will be too slow and unpredictable to provide the forest products and services required by increasing population growth. Enrichment planting is one such practice that preserves the actual stand. Artificial regeneration is introduced under a managed canopy so as to promote the growth of the planted trees while limiting the successional setback associated with clear-cuts. In the Monteregie region of southern Quebec, two centuries of severe deforestation and high-grading, followed by episodes of increase and decrease of agricultural activities, created a landscape of poorly regenerated patches of young forest stands without much economical value. Two such young early-successional tree stands of agricultural origin were enriched with red oak and black cherry in 1998 as a test for improving productivity in degraded stands in the northernmost part of the temperate forest of eastern North America. A release treatment was applied during the third growing season. The height increment after six years is analyzed with respect to canopy openness, presence of an intermediate vegetation layer, understory competition, and white-tailed deer predation. Height increment is positively associated with the opening of the upper canopy, and negatively with predation, which was not increased by the release. Understory competition was not significant. The release treatment succeeded in significantly increasing available light at 50 cm, 1 m and 2 m above ground, but this effect was rapidly compensated by the growth of the stand, re-closing the canopy. Planted trees, particularly red oak, responded well to the release treatment. When released, red oak had growth increments superior to published results for the species, with only a moderate thinning of the stand. Black cherry has survived but would require further release to achieve growth that better reflects its potential.é
Key words: Enrichment under-planting, Shelterwood, Quercus rubra, Prunus serotina