Allegheny blackberry

Appearance

Characteristics can be highly variable. It is an erect bramble, typically 5 feet but occasionally rarely over 8 feet high, with single shrubs approaching 8 feet or more in breadth, although it usually forms dense thickets of many plants. Leaves are alternate, compound, ovoid, and have toothed edges.

Canes adorning an armorment of pickles, with white, 5-petal, ¾ inch flowers in late spring and glossy, deep-violet to black, aggregate fruit in late summer. Shade intolerant.

Distribution

The presence of "Rubus allegheniensis" influences the dynamics of the understory vegetation of many forests in the eastern United States. An abundance of "Rubus allegheniensis" encourages new tree seedlings. Where the effects of herbivorous animals reduce the abundance of Allegheny blackberry, a competitor, "Dennstaedtia punctilobula", takes over. Where "Dennstaedtia punctilobula" becomes common, the growth of tree seedlings is restricted.

Concentrations of "Rubus allegheniensis" increase greatly after events that destroy taller shrubs and trees and thus permit more light into the understory, such as fires or widespread blowdown. These populations often decline in later years as the tree seedlings sheltered by the blackberry canes grow and reduce the amount of light reaching the lower levels.

Habitat

The presence of "Rubus allegheniensis" influences the dynamics of the understory vegetation of many forests in the eastern United States. An abundance of "Rubus allegheniensis" encourages new tree seedlings. Where the effects of herbivorous animals reduce the abundance of Allegheny blackberry, a competitor, "Dennstaedtia punctilobula", takes over. Where "Dennstaedtia punctilobula" becomes common, the growth of tree seedlings is restricted.

Concentrations of "Rubus allegheniensis" increase greatly after events that destroy taller shrubs and trees and thus permit more light into the understory, such as fires or widespread blowdown. These populations often decline in later years as the tree seedlings sheltered by the blackberry canes grow and reduce the amount of light reaching the lower levels.