Himalayan blackberry

Himalayan Blackberry (Rubus armeniacus) is a highly invasive shrub that forms dense, thorny thickets which crowd out native vegetation and block wildlife movement. It spreads rapidly by both seed and vegetative shoots, allowing it to dominate disturbed areas, woodland edges, and streambanks.

Although primarily established in western states such as Oregon, Washington, and California, it could become a serious threat if introduced in Wisconsin. Anyone who encounters this species should report it immediately to the Wisconsin Department of Natural Resources to help prevent its spread and protect native habitats.

Ecological Threat

• This species was once introduced into the United States as a horticultural blackberry.
• Prefers full sun; also shade tolerant, flooding and drought-resistant, and adaptable to various open and wooded habitats, wetlands, riparian areas, old fields and disturbed areas.
• Forms dense, impenetrable thickets in natural habitats, dominating the forest understory by shading and crowding out native plants and impeding tree establishment.
• Spreads via seed, vegetatively through rhizomes, and by tip-rooting (tips of canes root upon contact with the ground).
• Birds readily eat and disperse the fruits, resulting in new infestations far from the initial source.
• Very invasive and widespread across the western United States, as well as in the Northeast.