California Invasive Plant Council

Centaurea diluta

Common names: North African knapweed

Centaurea diluta (North African knapweed) is an annual herb/ (family Asteraceae) with pink-purple flowers and lobed leaves found in the San Francisco Bay area and south coast ranges of California. It is native to southwestern Europe. It favors grasslands. Its hairy seeds are dispersed via wind. It was said to have been introduced to Great Britain as a contaminant in bird seed.

Cal-IPC Rating: Watch

CDFA Rating: None?

Explanation of CDFA ratings

• A – A pest of known economic or environmental detriment and is either not known to be established in California or it is present in a limited distribution that allows for the possibility of eradication or successful containment.
• B – A pest of known economic or environmental detriment and, if present in California, it is of limited distribution.
• C – A pest of known economic or environmental detriment and, if present in California, it is usually widespread.
• D – An organism known to be of little or no economic or environmental detriment, to have an extremely low likelihood of weediness, or is known to be a parasite or predator.
• * – An asterisk next to the rating indicates that a plant is included in the CCR Section 4500 list of California State Noxious Weeds.

More details

Assessment(s)

Plant Risk Assessment - An evaluation of the potential for a plant to be invasive in California.

Weed Management Notes

Cal-IPC Newsletter Articles

• Celebrating park stewards. Cal-IPC. Vol 24, Issue 2

Cal-IPC Symposium Presentations

Presentations are linked where available. Where a presentation is not available, find more information by reading the abstract in the Cal-IPC Symposia Archive.

• 2019 Weed Alerts. Burger, Jutta; Price, Bob (2019)

Other Centaurea diluta Information

• CalPhotos - Images of plants taken mostly in California.
• Calflora - Distribution map and records of this species in California.
• CalWeedMapper - Distribution map of this species in California with ability to determine regional priorities.
• EDDMapS - Distribution of this species in North America.
• Jepson Interchange - Information on this plant's taxonomy, biology, and distribution from UC Berkeley's Jepson Herbarium.
• USDA PLANTS Database - Information on identification and distribution, with links to websites in individual states.