FACTORS AFFECTING GERMINATION AND EARLY SURVIVAL OF YELLOW BIRCH (Betula lutea Michx.) IN QUEBEC

Abstract

Very few studies directly concerning the factors which favor yellow birch re~roduction can be found in the bulk of literature on the management of ~o r t h e r n Hardwoods. A number of papers exist, however, w&ch show the place of yellow birch in virgin and cut,over forest stands. The only intensive investigation ever made of the species was conducted in the Adirondack Forest by McCarthy and Belyea (1920). The writers mentioned among others the following facts leading to the study of the species: yellow birch possesses certain advantages over-the three important competing hardwoods -beech, sugar maple, and red maple-in seizure of devastated areas. These advantages are the greater motility of yellow birch seeds; large annual crops of seeds having few enemies; the capacity of the seeds to germinate on deep humus or partially decayed wood and successful rooting through deep layers of such material to the mineral soil; the species in its seedling and sapling stages grows quickly enough to compete with tolerant hardwoods and assures the tree a dominant place in the ultimate stand of trees. Moreover, the crown of birch interce~ts less light than those of the m a ~l e s and beech. so that it allows a bette; growthuof the understory of scktwoods. ina all^, cut-over lands were observed to have dense stands of young birch, and it was believed that the ultimate forest. would have a larger percentage of birch than the virgin forest.