Land Plants - non-native

Knapweed (species unknown) (Centaurea) on Sep 24, 2022

Submitter does not have a specimen
EDRR Status: Local expert notified

Description of specimen

Large areas of knapweed in with teasel and grasses. OSU owns this property. Not located within Corvallis city limits. ID (guess) is visual, from sidewalk when it was in bloom.

Commentary

None

Resources

There are many non-native knapweeds present in Oregon, and their identification can be difficult. Some species hybridize. Here is one resource for identification: Identification of starthistles and knapweeds in the Pacific Northwest, but there may be more recent descriptions available.

Location

Open field on slight slope next to NW Witham Hill Drive. West side of street. Access is on foot. Park temporarily near old shed/lean-to near top of street. There is currently an opening in the fence along Witham Hill drive that allows foot access to the field. Follow the sidewalk downhill to the opening.

Expert Reviewer

Michael Ahr
Benton Soil and Water Conservation District

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