Coreopsis hamiltonii

Coreopsis hamiltonii, the Mt. Hamilton coreopsis, is a rare California species of "tickseeds" in sunflower family. It is found only in a small region including Mount Hamilton and the Diablo Range in the southwestern San Francisco Bay Area (Alameda, Santa Clara, and Stanislaus Counties).
Description.
"Coreopsis hamiltonii" typically grows tall or sometimes taller when in bloom. The foliage is low growing, producing bright golden yellow colored flower heads and red purplish tinted peduncles. The foliage is deeply cut with a thin ferny shape.
It can be found blooming from March to May in California, where plants are found growing from above sea level.