|Biological agent type
seed head weevil
Plant species attacked
diffuse knapweed (Centaurea diffusa)
spotted knapweed (Centaurea stoebe)
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Images by Eric Coombs, Oregon Department of Agriculture.
If images are downloaded and used from the ODA web site please be sure to credit the photographer.
Site of attack
Mode of attack
The weevil attacks the early buds, and appears to contribute to the impacts of Larinus minutus. Larvae consume most of the contents of infested seed heads.
Collection and release information
Bangasternus fausti is widespread in some areas of Oregon. The adults can be collected by sweep net May-June. Consult with ODA for availability for your area.
History in Oregon
The seedhead weevil Bangasternus fausti was introduced in Jackson County in 1989. It is now widespread and abundant in most knapweed infested counties in Eastern Oregon.
Release status in Oregon
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