The River Birch has simple, alternately arranged leaves that have a ovate to deltoid (triangular) shape, a pointed tip, and a doubly serrate margin. The leaf is dark green above and pale green and pubescent (hairy) below. In some leaves, the capillary veins between axillary veins are easily visible.
Twig and Bud Identification
The twig is green-gray and densely pubescent when young with small, fuzzy hairs that will fade with age. There are also numerous small pale lenticels (pores) present. The bud is pubescent at first, then only at the fringes of its bud scales. It is dark reddish-brown, as is the mature twig.
The River Birch has a distinctive peeling bark that peels horizontally in irregular patches of various colors, from cream to pink-orange. The older bark becomes more scaly.
The fruits of the River Birch are the mature female catkins, still in a conical shape but with thin greenish-brown seed coats sticking out between the now-brown scales in a hanging cluster. They mature in late spring and summer.
The River Birch is monoecious; both male and female flowers exist on one tree, albeit not within the same flower. Both the male and female flowers are catkins. The male catkins are hanging, yellow-brown, and much longer than the female catkins, which are upright on the branch, green with red stigmas, and scaled. They both bloom in early spring.