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U.S. Forest Service

Critically Imperiled Plant Profile (Not Listed or Proposed under the Endangered Species Act)

Phacelia cookei. Recent phylogenetic analysis that tiny-flowered P. cookei is sister to P. suaveolens ssp. keckii, another extremely rare phacelia, which is restricted to the Cleveland National Forests in Orange and Riverside Counties, southern California. This photo shows Cooke’s phacelia in full flower! Photo by Kim Earll.

Phacelia cookei. Cooke’s phacelia grows only in a small area of far northern California: at the northern base of Mt. Shasta, a volcano in the southern Cascade Range; it is limited to areas of high disturbance on ashy, volcanic sand, in and along unpaved roads where there is low surface organic matter and little competition from other plants. Photo by Kim Earll.

Phacelia cookei range map. Phacelia cookei range map.

Phacelia cookei, Cooke’s phacelia


  • Non-native plants, especially cheatgrass (Bromus tectorum).
  • Road maintenance.
  • Possibly fire suppression.

Conservation Status

National Forest and Grassland Occurrence

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