Phacelia argentea

Common Names:
sand-dune phacelia, silvery phacelia
A. Nels. & J.F. Macbr.
Growth Habit:
CPC Number:
Profile Contributors:
Fully Sponsored

Reference Links

ITIS - Tropicos - USDA Plants - Fish & WildLife

Participating Institutions

The following Participating Institutions are custodians for this species in the CPC National Collection:
Rae Selling Berry Seed Bank & Plant Conservation Programs

The conservation of Phacelia argentea is fully sponsored.


Silvery phacelia is the only known Phacelia to grow on coastal sand dunes (Rittenhouse 1995). It grows on the immediate coastal dunes from northern Del Norte County in California to southern Coos County in Oregon. Although this seems like a large distribution (it spans 130 miles), not all of this stretch of coast is suitable habitat because much of the coastline is sharp cliffs or rocks, not sand dunes (Rittenhouse 1995). The encroachment of non-native European beachgrass is reducing this habitat even further.

The coast of California and Oregon had a dramatically different appearance 150 years ago. Many beaches had no fore-dune, and in areas where dunes formed, they ran perpendicular to the shore (Russo et al. 1988). European beachgrass was introduced in the late 1800's to stabilize the beach sand. It does its job very well, a little too well in fact. European beachgrass outcompetes native vegetation and alters the native dune community by creating steep foredunes as it traps blowing sand. These steep foredunes run parallel to the shore, a stark contrast to the natural state of the dunes (Russo et al. 1988). In areas where European beachgrass is dominant, silvery Phacelia populations are both small and fragmented or totally nonexistent (Rittenhouse 1995).

Although there are many known populations of Silvery Phacelia compared to other rare species, the majority of populations are small and separated by great distances. Reports indicate that most appear to be declining in numbers (Rittenhouse 1995).

Distribution & Occurrence


Conservation, Ecology & Research