The following Participating Institutions are custodians for this species in the CPC National Collection:
Cincinnati Zoo & Botanical Garden
The conservation of Phlox hirsuta is fully sponsored.
Holly Forbes contributed to this Plant Profile.
Yreka phlox is a narrow endemic perennial plant with pink to white flowers. Its found only in the area of the city of Yreka, in extreme northern California. It grows from two to six inches tall, though stems growing along the ground can be longer. The stems are densely hairy (hirsute). The plants at the five extant locations vary in number from 200 to 10,000 plants on both private and public lands. (Recovery Plan)
Distribution & Occurrence
Yreka phlox is endemic to serpentine substrates (i.e., found only on soils derived from ultramafic parent rocks) from near 900 meters to 1,300 meters elevation. It grows on shallow to somewhat deep soils with moderate to high erosion potential. Vegetation ranges from serpentine barrens to openings in juniper, oak, or pine woodlands. (Recovery Plan)
|Five populations of 200 to 10,000 plants. (Recovery Plan)|
Conservation, Ecology & Research
Competition with non-native plants
Domestic Animal Grazing
Seed set in a subsample of P. hirsuta plants ranged between 78 and 92 percent and seed viability was recorded as high as 84 percent (Ferguson 2004, Ferguson and Filipski 2005).
Of viable seeds that were planted in pots in the laboratory, 68.5 percent produced viable seedlings. Seedlings raised in a greenhouse took 4 to 22 days to emerge from the soil (Ferguson and Filipski 2005).
Seed dispersal in habitat
Seed germination in habitat
Seedling establishment in habitat
Studies of life history, breeding system, pollinators, and effects of soil disturbance and fire management are needed.
Development of propagation techniques
Ferguson, C. 2004. The importance and identification of insect pollinators of the Yreka phlox (Phlox hirsuta E.E. Nelson). First progress report and addendum. Redding. California Department of Fish & Game.
Ferguson, C.; Filipski, J. 2005. The importance and identification of insect pollinators of the Yreka phlox (Phlox hirsuta). March 2005 progress report. Redding. California Department of Fish & Game.
U.S. Fish and Wildlife Service . 2006. Recovery Plan for Phlox hirsuta (Yreka Phlox). Sacramento. USFWS.