Louisville, KY (Zone 6b) | January 2015 | positive
Virginia Roundleaf Birch may is one of the rarest native U.S. tree species still growing in the wild. The only known natural population g...Read Morerows along a creek in Smyth County in southwest Virginia. First described in 1916, it was feared extinct until about 20 trees were found in 1975.
Seeds were collected from the existing trees and planted in other selected areas, and by 1992 a total of more than 1400 plants were growing at 20 different locations. A 2006 census found 900. In 1994 the U.S. Fish and Wildlife Service changed the official status of the species from Endangered to Threatened. As a result, it is now possible for you to grow this plant on your own property.
The tree, which is also called Ashe Birch, can reach a mature height of about 40 ft. But 20 ft. Seems to be its average height. It has a narrow trunk and an oval crown of many slender branches. Unlike most birches, it has dark bark and distinctly rounded leaves. Both leaves and bark release a wintergreen scent when crushed. In the fall the tree produces a small cone-shaped fruit containing tiny nutlets.
The existing wild trees might be the last survivors of what was once a more widespread species. But they could also be early specimens of a newly-evolved species which hasn't yet had time to expand into a larger area. The wild trees are located near some Sweet Birches (Betula lenta), and the two species appear to be closely-related. It's possible that the roundleaf birch is a recent evolutionary split-off.
Since little is known about this tree's growing requirements, it is assumed they are similar to its close relate B. lenta, please share your experiences and observations. B. uber may be a bit more heat tolerant than B. lenta since it naturally occurs in the southern portion of zone 6. B. lenta has done very well in the Midwest, so might uber. If grown in zone 7, it should probably be grown on a northern exposure to help keep the soil from drying in summer heat.
Forest Farm has offered it in the past. Searching a few days ago, I could only find it through Nebraska Statewide Arboretum.
Betula uber (Dec) (z6) (ENa,Bon)
Once thought to be extinct & still very rare, this small 20-25' Birch has dark bark with a winte...Read Morergreen fragrance to its leaves; (these plants are grown from seed collected from cultivated trees, not wild). Sun/Med
Virginia Roundleaf Birch may is one of the rarest native U.S. tree species still growing in the wild. The only known natural population g...Read More
Betula uber (Dec) (z6) (ENa,Bon)
Once thought to be extinct & still very rare, this small 20-25' Birch has dark bark with a winte...Read More