Sweet birch

Appearance

''Betula lenta'' is a medium-sized deciduous tree reaching 30 m tall, exceptionally to 35 metres with a trunk up to 60 cm diameter. Heights of 50 feet to 80 feet are more typical.

In younger trees the bark is characteristic of most birches, with smooth bark and distinct horizontal lenticels. It is sometimes mistakenly identified as a cherry tree. In older tree specimens the bark develops vertical cracks into irregular scaly plates revealing rough dark brown bark patterns. This, however, only occurs in mature, or ancient, trees and these specimens are not often identified by the public as ''B. lenta'' due to the difference between the tree's smooth young bark and the tree's rough, cracked and plated mature bark.

The twigs, when scraped, have a strong scent of wintergreen due to methyl salicylate, which is produced in the bark. The leaves are alternate, ovate, 6–15 cm long and 4 to 8 cm broad, with a finely serrated margin. The flowers are wind-pollinated catkins 2.5–3 cm long, the male catkins pendulous, the female catkins erect. The fruit, maturing in fall, is composed of numerous tiny winged seeds packed between the catkin bracts. Seed production mainly occurs in trees that are between 40 and 200 years old, although light crops may occur as early as 15 years and as long as the tree lives.