Common Name: Virginia round-leaf birch
Type: Tree
Family: Betulaceae
Native Range: Virginia
Zone: 5 to 7
Height: 15.00 to 30.00 feet
Spread: 10.00 to 20.00 feet
Bloom Time: April to May
Bloom Description: Green female catkins and greenish-yellow male catkins
Sun: Full sun to part shade
Water: Medium
Maintenance: Medium
Suggested Use: Shade Tree, Naturalize
Flower: Insignificant
Leaf: Fragrant, Good Fall
Culture
Best grown in rich, slightly acidic, evenly moist, well-draining, humusy loams in full sun to part shade. Most likely hardy in Zones 5-7. Because of the relative rarity of this species in cultivation, its preferred growing condition are not well studied. Will likely do well in climates and growing conditions similar to those preferred by Betula lenta and B. alleghaniensis.
Noteworthy Characteristics
Betula uber, commonly called 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.
Genus name is the Latin name for birch.
The specific epithet uber means "abundant" or "fruitful", in reference to the female cones that line the twigs.
The common name Virginia round-leaf birch refers to the native range of this species as well as the shape of its foliage.
Problems
No major pest or disease problems of note have been recorded in wild populations. However most birches are susceptible to to a wide range of pest and disease issues, including aphids, birch skeletonizer, birch leafminer, canker, leaf spot, and leaf rust, so it is can be presumed that this species would suffer from at least some of these typical pests and pathogens.
Uses
Woodland edges, streambanks, parks, lawn specimens.