Birch, Round Leaf

Description:

Virginia round-leaf birch is a small, deciduous tree endemic to Smyth County in western Virginia. This tree was only known through a herbarium specimen collected in 1914 until it was rediscovered in the wild in 1975. Though only one, dwindling, naturally-occurring population is known today, planting efforts using ex-situ propagated progeny has increased the overall population in the wild.

Mature plants will reach 15-30′ tall with a 10-20′ wide, oval to pyramidal-shaped canopy. Exceptional specimens exceeding 45′ tall have been recorded. Mature bark is grey-brown in color, relatively smooth and thin with slender, horizontal lenticles. The twig bark is dark reddish-brown to nearly black with scattered, round lenticles. The leaves and inner bark are aromatic and produce a wintergreen scent. The 1-2″ long and 1-1.75″ wide foliage has irregularly serrated margins, ranges in shape from almost circular to broadly elliptic, and turns bright yellow in the fall. The upright, green female catkins emerge in mid-spring along the twig ends and will reach 0.75-1″ long. They mature to brown and release small, winged nutlets (samaras) in the fall. The pendulous male catkins will expand to reach up to 2.5″ long in spring. Similar to (and sometimes listed as a variety of) B. lenta, although genetic analysis has upheld its species status and pointed to B. alleghaniensis as the more closely related species.