They are frequently covered with a resinous matter, as in balsam-poplar and horsechestnut, or by a thick downy covering as in the willow.
Next in importance after spruce, in the interior, is birch, and then balsam poplar.
A small Western balsam poplar P. trichocarpa is found along the footpath on Dog Kennel Hill.
They contain the poplar or aspen (Populus tremuloides), balsam poplar (Populus balsamifera), and paper or canoe birch (Betula papyrifera).
The flora of the Hudsonian and the Canadian zone consists largely of white and black spruce, tamarack, canoe-birch, balsam-poplar, balsam-fir, aspen and grey pine.
