Lilaeopsis masonii

Mason's lilaeopsis

Family: Apiaceae · Type: perennial · Native

Conservation status: CNPS 1B.1

Mason's lilaeopsis is a rare (CNPS 1B.1) California native perennial found in southern Sacramento Valley, northern San Joaquin Valley, central California Coast, and northeastern San Francisco Bay regions in intertidal marshes and streambanks at elevations below 36 meters. Flowering from June to August, this plant produces tiny white flowers on short peduncles with delicate, thread-like umbels. Growing in dense, compact tufts with vertical branching, it forms slender stems that spread in low, intricate patterns across wet habitats. Its leaves are linear and thread-like, typically clustered at branch tips and measuring 1.5 to 7.5 centimeters long, creating a fine, grass-like appearance. The fruit develops as small elliptic structures about 1.2 to 1.6 millimeters long, with distinctive marginal ribs and 5 to 6 internal oil tubes.

Habitat: Intertidal marshes, streambanks

Bloom period: Jun-Aug

Elevation: < 36 m

Bioregions: s ScV, n SnJV, CCo (Inverness, Point Reyes), ne SnFrB.

California counties: Solano, San Joaquin, Contra Costa, Sacramento, Napa, Marin

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