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

view all news »
posted: August 13, 2018
Invasive fish found breeding near Prince George - Don’t Let It Loose!

The province says an invasive fish - commonly sold as feed for other fish - has been found breeding in a tributary to the Fraser...

posted: August 12, 2018
Clean Drain Dry - help keep things like the “zombie” plant out of our waterways!

There are native milfoils in BC, but Eurasian water-milfoil is a concern in many parts of eastern Canada and the US, and has been found in...