Betula lenta is a deciduous Tree growing to 24 m (78ft 9in) at a fast rate.
It is hardy to zone (UK) 3. It is in flower in April, and the seeds ripen in October. The species is monoecious (individual flowers are either male or female, but both sexes can be found on the same plant) and is pollinated by Wind.
Suitable for: light (sandy), medium (loamy) and heavy (clay) soils, prefers well-drained soil and can grow in heavy clay soil. Suitable pH: acid, neutral and basic (alkaline) soils and can grow in very acid soils.
It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.
Betula lenta (sweet birch, also known as black birch, cherry birch, mahogany birch, or spice birch) is a species of birch native to eastern North America, from southern Maine west to southernmost Ontario, and south in the Appalachian Mountains to northern Georgia.
Betula lenta is a medium-sized deciduous tree reaching 30 m (98 ft) tall, exceptionally to 35 metres (115 ft) with a trunk up to 60 cm (2.0 ft) diameter. Heights of 50 feet (15 m) to 80 feet (24 m) 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 (unlike the more commonly known birches) 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 (which the public is most familiar with) 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 (2.4–5.9 in) long and 4 to 8 cm (1.6–3.1 in) broad, with a finely serrated margin. The flowers are wind-pollinated catkins 2.5–3 cm (0.98–1.2 in) 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.