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