Will Elder, NPS
1. Rare, but found in sufficient numbers and distributed widely enough that the potential for extinction or extirpation is low at this time.
Family: Sunflower (Asteraceae)
Habitat: Frequents wet or marshy ground along streams and seeps, sometimes on serpentine soils.
General Distribution: Coastal counties from Sonoma to San Mateo. In the Presidio, this species is found on the bluffs near Fort Point.
Description: This robust thistle stands up to six feet tall and the stems can reach two inches in diameter. The stems and upper surfaces of the leaves are thinly cobwebby, as are the leaf undersides. The rosy purple flower heads are also densely cobwebby. Blooming time is June to July. Superficially, this species resembles the common non-native bull thistle.
Monitoring and Activities: The population near Fort Point has been declining in recent years. However, two distinct populations have been discovered on the coastal bluffs in the past three years and are stable. Experimental seeding of other sites also is under way. Click to see a map of plant distribution.