Himalayan blackberry
(Rubus armeniacus Focke)

Overview

Appearance

Rubus armeniacus is a perennial shrub, that is native to Eurasia. Stems grow to 15 ft. (4.6 m) before arching and trail the ground for up to 40 ft. (12.2 m).

Foliage

The leaves of the prima cane (first year shoots) are 2.8-7.9 in. (0.9-2.4 cm) long and are palmately compound with 5 leaflets. In the second year, several side shoots are produced (flora canes) having smaller leaves with 3 leaflets. The leaflets are oval and toothed with thorns along the underside of the mid-rib.

Flowers

No flowers are produced in this plant’s first year of life. Flowering occurs in late spring to early summer; when white to pale pink flowers develop on the flora canes. Flowers have five petals, numerous stamens and are 0.8-1 in. (2-2.5 cm) in diameter.

Fruit

Fruits are an aggregate of drupelets that are black, when mature, and 0.5-0.8 in. (1.3-2 cm) in diameter.

Ecological Threat

As the plant grows and the stems touch the ground they root at the nodes, producing a dense thicket that shades out other plant species.

Resources

• Element Stewardship Abstract - The Nature Conservancy

Selected Images

Maps

Invasive Listing Sources

• California Invasive Plant Council
• Georgia Exotic Pest Plant Council - Category 3
• Jil M. Swearingen, Survey of invasive plants occurring on National Park Service lands, 2000-2007
• John Randall, The Nature Conservancy, Survey of TNC Preserves, 1995.
• Missouri SRISP Species List
• Native Plant Society of Oregon, 2008
• New Jersey Invasive Species Strike Team 2017 Invasive Species List
• Non-Native Invasive Plants of the City of Alexandria, Virginia
• Oregon Noxious Weeds
• Pacific Northwest Exotic Pest Plant Council, 1998
• Reichard, Sarah. 1994.  Assessing the potential of invasiveness in woody plants introduced in North America. University of Washington Ph.D. dissertation.
• Washington Noxious Weeds
• WeedUS - Database of Plants Invading Natural Areas in the United States
• Wisconsin Noxious Weeds
• Wisconsin's Invasive species rule – NR 40

References