Betula nigra catkins long, the male catkins pendulous, the female catkins erect. The fruit is unusual among birches in maturing in late spring; it is composed of numerous tiny winged seeds packed between the catkin bracts. "Betula nigra" is a tree that falls into the family of Betulaceae, which is commonly known as the Birch or Alder Family. This family comprises six genera ("Alnus, Betula, Carpinus, Corylus, Ostrya," and "Ostryopsis)" and includes alders, birches, hornbeams, and hazelnuts. Species within this family, along with "Betula nigra", are shrubs or trees that grow along stream sides or in poorly drained soils throughout the Northern
Chrysolepis three sweet, edible nuts, eaten by the indigenous peoples. The fruit also provides food for birds and wildlife. "Chrysolepis" is related to the subtropical southeast Asian genus "Castanopsis" (in which it was formerly included), but differs in the nuts being triangular and fully enclosed in a sectioned cupule, and in having bisexual catkins. "Chrysolepis" also differs from another allied genus "Castanea" (chestnuts), in nuts that take 14–16 months to mature (3–5 months in "Castanea"), evergreen leaves and the shoots having a terminal bud. There are two species of "Chrysolepis" — "Chrysolepis chrysophylla" and "Chrysolepis sempervirens" — which like many species