Chorizanthe robusta var. robusta
Robust spineflower
Family: Polygonaceae · Type: perennial · Native
Conservation status: CNPS 1B.1 · Endangered
Robust spineflower is a rare (CNPS 1B.1) California native perennial found in north and central Coast Ranges of Santa Cruz and Monterey counties, and historically in southwestern San Francisco Bay area, inhabiting sandy or gravelly terrain at elevations of 10 to 300 meters. Flowering from May to September, this plant produces white flowers in delicate involucres 2.5 to 4 millimeters wide with distinctive white-margined lobes. Growing with spreading or decumbent stems 10 to 20 centimeters long, it forms low, intricate ground-hugging patches. Its leaves are slender, with blades 1.5 to 5 centimeters long and remarkably narrow, measuring just 0.3 to 0.7 centimeters wide. This uncommon spineflower thrives in sparse, open coastal habitats, adapting to challenging sandy environments with its compact growth form.
Habitat: Sand or gravel
Bloom period: May-Sep
Elevation: 10-300 m
Bioregions: n&c CCo (s Santa Cruz, n Monterey cos.), sw SnFrB (extirpated).
California counties: Santa Cruz, Marin, San Mateo, Monterey, Alameda
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Jepson eFlora, Cal-IPC, and more.