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Buffalobur identification and control: Solanum rostratum

Buffalobur identification and control

Solanum rostratum

buffalobur flowers and stem
Although buffalobur is native to the midwestern United States, it is widely introduced elsewhere. It has been introduced to the Pacific Northwest multiple times, often as a seed contaminant in flowers, vegetables and even birdseed. It can spread quickly by seed and is able to grow in a wide range of conditions. The burs are a serious nuisance to wool producers even in the plant's native range and this spiny plant can be a real pest on a farm or in range areas.


Legal status in King County, Washington


Buffalobur is a Class C noxious weed in Washington, selected by the King County Noxious Weed Control
Board for required control. In King County, property owners are required to control it when it occurs on their property. It is also on the Washington quarantine list (also known as the prohibited plants list) and it is illegal to buy, sell or offer it for sale in the state of Washington. It has a very limited distribution in Washington. For more information on noxious weed regulations and definitions, see Noxious weed lists and laws.

Additional information on buffalobur

What to do if you find this plant in King County, Washington


Please notify us if you see buffalobur growing in King County. Our program staff can provide the property owner or appropriate public agency with site-specific advice on how best to remove it. Also, because buffalobur is not established in King County, we have an opportunity to stop it from spreading if we act quickly. We map all known locations of regulated noxious weeds such as buffalobur in order to help us and others locate new infestations in time to control them.

Buffalobur photos


buffalobur plant

Report buffalobur in King County, Washington

Locate buffalobur in King County, Washington

Related information

Related agencies

Program offices are located at 201 S. Jackson St., Suite 600, Seattle, WA 98104. To contact staff, see the Noxious Weed Control Program Directory, send an email, or call 206-477-WEED (206-477-9333).