Acroptilon repens (Russian knapweed)

Acroptilon repens

Photo courtesy David Chang

Acroptilon repens (Russian knapweed) is a perennial forb (family Asteraceae) found heavily through out California. It may have allelopathic properties. This plant is toxic to horses and crowds out native species.

Cal-IPC Inventory rating: Moderate

Cal-IPC Resources on Acroptilon repens

• California Invasive Plant Inventory Assessment Form (pdf) - Information gathered by Cal-IPC on the impacts, rate of spread, and distribution of invasive plants in California. Does not include management information.
• Cal-IPC News - Articles from our quarterly newsletter. (None for this species.)
• Cal-IPC Symposium Proceedings - Presentations and papers from our annual Symposium. List of articles on Acroptilon repens.

Cal-IPC News Articles

• None for this species.

Symposium Proceedings

• Carrithers, V., B. Miller, et al. (2005). Aminopyralid: A new reduced risk active ingredient for control of broadleaf invasive and noxious weeds. California Invasive Plant Council Symposium 2005. Chico, CA.
• Clines, J. (2005). Preventing weed spread via contaminated hay and straw. California Invasive Plant Council Symposium 2005. Chico, CA.
• Donaldson, S., W. West, et al. (2003). Getting the job done: Working within the regulatory environment at Lake Tahoe to manage weeds. California Invasive Plant Council Symposium 2003. Kings Beach, California.
• Gerlach, J. D. (1997). How the west was lost: Reconstructing the invasion dynamics of yellow star-thistle and other plant invaders of western rangelands and natural areas. California Exotic Pest Plant Council Symposium '97. Concord, CA.
• Smith, R. L., V. F. Carrithers, et al. (2006). Managing rangeland invasive plants with Aminopyralid (MilestoneTM). Cal-IPC Symposium. Rohnert Park, CA.

Other Resources on Acroptilon repens

• USDA PLANTS database - Federal database with information on identification and distribution, and links to websites in individual states.
• Jepson Online Interchange for California Flora - Information on taxonomy, biology, and distribution from the UC Berkeley Jepson Herbarium.
• The Nature Conservancy Management Summary - Information compiled by TNC land managers. Photos included for some species.
• CalFlora - Distribution information by county based on submitted observations and herbarium specimens.
• CalPhotos - Images of plants taken mostly in California.
• Natural Resource Projects Inventory - State database with information on resource management projects throughout California. Query by the species of interest.

Printer-friendly version