Plagiobothrys strictus

Calistoga popcornflower

Family: Boraginaceae · Type: annual · Native

Conservation status: CNPS 1B.1 · Endangered

Calistoga popcornflower is a rare (CNPS 1B.1) California native annual found in southern North Coast Range Interior bioregion in northwestern Napa County, occurring in moist to wet sites near hot springs and vernal pools at elevations of 100 to 150 meters. Flowering from March to June, this plant produces white flowers with yellow appendages in delicate clusters approximately 4 to 6 millimeters in diameter. Growing with ascending to erect stems 10 to 40 centimeters tall, the plant is mostly smooth with fine hairs concentrated on the flower calyx. Its cauline leaves are elongated, with lower leaves reaching 4 to 9 centimeters in length. The fruit consists of small, flat nutlets with intricate surface textures featuring narrow, irregular cross-ribs and a linear scar near the base.

Habitat: Moist to wet sites near hot springs, adjacent vernal pools, occasionally grassy swales

Bloom period: Mar-Jun

Elevation: 100-150 m

Bioregions: s NCoRI (nw Napa Co.).

California counties: Napa, Lake, Sonoma

Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Jepson eFlora, Cal-IPC, and more.