Black Birch (Betula lenta)

A deciduous tree from the Birch Family (Betulaceae)

Black Birch is a tree found in the Appalachian region of the United States, mostly in moist ravines where there are cool summers. In Ohio, it is only native along the western edge of the Allegheny Plateau. It is prized for its hard, heavy wood (used as a finish wood or veneer, and often stained or varnished), and its excellent yellow fall color. It is named for its mature black bark that resembles that of Black Cherry, and it is also known as Cherry Birch or Sweet Birch. Its twigs, if broken, have the strong scent of wintergreen (Yellow Birch also has this trait, but with reduced aroma), and the leaves and twigs may be distilled to extract this flavoring.

When found in the open, Black Birch may reach 50 feet tall and 40 feet wide as an individual tree. As a member of the Birch Family, it is related to the Alders, Hornbeams, Filberts, and Hophornbeams, in addition to other Birches. It is often found growing alongside Yellow Birch (with which it is often confused) in regions where they overlap, inhabitating cool forests, moist ravines, and also colonizing fields and roadway cuts.

Planting Requirements - Black Birch prefers moist, rich, deep, well-drained, acidic soils in sites that have relatively cool summers. It tolerates drier soils, and somewhat tolerates soils of alkaline or neutral pH, but does not compete well in the wild or perform well in urban landscapes under these conditions. It grows in full sun to partial shade, and is found in zones 3 to 7.

Potential Problems - Black Birch, like most Birches, has many pathogens (leaf diseases, trunk rot, bark cankers) and pests (bronze birch borer being the worst) which can cause either cosmetic or lethal injury to the tree. The most common cases where this occurs is when the tree is grown outside of its natural range, where it undergoes environmental stresses (high pH soils, dry soils, hot summers, and mild winters) that make it much more subject to biological attack.

Leaf Identification Features

Leaves of Black Birch are alternate, elliptical to ovate, and singly to doubly serrated on their margins.

In summer they are dark green and shiny, and densely clothe the twigs and branches in the tree canopy. In autumn, the leaves of Black Birch turn bright yellow and gold, considered by most to be the best and most consistent of any Birch.

Other Identification Features

In winter, the immature catkins (male flowers) of Black Birch hang from the slender twigs, and create a slightly more dense region of the canopy where they predominate (the upper reaches in the top photo).

The female flowers form within the lateral buds and are not seen until early leaf emergence the following spring on this monoecious species. Fertilized female flowers give rise to green cones in spring, which later turn brown and shatter, releasing their seeds in late summer and early autumn.

The texture of Black Birch in winter is medium-fine, with the ascending branches having thin, hairless twigs and small, sharply-pointed buds. The twigs, if broken, have the strong scent of wintergreen (Yellow Birch also has this trait, but with reduced aroma).

Black Birch has young branches with a smooth, glistening, brown to red-brown to black bark in winter, with prominent, lighter-colored lenticels. Young trunks have the same traits, but transition to brown-black bark that breaks up into plates and scales with age.