Les successions secondaires sur sites mésiques dans le Haut-Saint-Laurent, Québec, Canada

Abstract

Secondary succession on mesic sites was studied in 10 forest stands in the Haut-Saint-Laurent region, using diameter-class distribution and dendrochronological analysis. Size-class ordination allowed the determination of two seral successions associated with forest communities of clear-cut or abandoned field origin. Forest cutting favors vegetative resprouting of Tilia americana, Ostrya virgininiana, and Prunus serotina rather than seed invasion of species from neighbouring communities. Fraxinus americana, Betula populifolia, and Ulmus americana colonize abandoned fields. Whatever the nature of the disturbance, strong regeneration and high shade tolerance leads to the eventual dominance of the sugar maple and to what appears to be succession convergence. However, a situation where the sugar maple is replaced by the American beech is an old community raises questions concerning the stability of the so-called climax maple forest.