Diffuse Knapweed

BC Min of Agr BC Min of Agr L Scott L Scott

Plant Bio

Common Name:Diffuse knapweed
Family:Asteraceae
Genus:Centaurea
Species:diffusa Lam.
Classification/Rank:Extremely Invasive
Method of Transportation:By seeds stuck on vehicles, in hay and on/through animals.
Habitat/Range:Well drained soils in open areas such as grasslands and open forests. Can also establish along roadsides. Cannot tolerate excessive moisture or cultivation.

Description

Diffuse knapweed (Centaurea diffusa)is a weed of dry, open landscapes. It has sharp white spines ("bracts") on the flower-head and usually has white disk flowers (although they can be purplish). It is a biennial or short-lived perennial and it grows up to 1 m tall. This plant forces out native species and it's allopathic properties (which alter the chemistry of the soil) can prevent other plants from growing in the same vicinity. 

For more information on Diffuse knapweed check out the Weeds BC Diffuse knapweed info sheet or contact the NWIPC. If you would like to report this weed call the NWIPC at 1-866-44WEEDS or use the Report-A-Weed application.

News

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posted: August 28, 2018
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