Betula uber Betula uber Betula uber, Virginia round-leaf birch, is a rare species of tree in the birch family. One of the most endangered species of North American trees, it is endemic to Smyth County, in the U.S. state of Virginia. It is part of the temperate broadleaf and mixed forests biome. The tree was first described in 1918 as a variety of "Betula lenta", and elevated to species status in 1945. It hybridizes with "B. lenta" and it has been suggested that it is actually a round-leaved mutant form of "B. lenta". Some authorities prefer to treat it as a variety.
Terminalia sericea to tall. The bark is a reddish or greyish brown colour and peels away in strips. The bluish-green leaves tend to be clustered at the tips of the branches. They are ovate with entire margins and both the upper and lower surfaces are clothed in silvery hairs. The flowers are white and are borne in short axilliary spikes. They have an unpleasant smell and may be pollinated by flies. The fruit are winged nuts containing a single seed and turn a darker pink colour as they ripen. They may remain attached to the branch for a year and are dispersed