Euphorbia helioscopia

Wartweed, Wartweed

Family: Euphorbiaceae · Type: annual · Not Native

Wartweed is a naturalized annual found in northern California Coast Ranges, San Francisco Bay Area, Central Coast, and Southern California coastal areas in disturbed areas at elevations below 200 meters. Flowering from April to July, this plant produces small, green-tinged flowers in complex clustered cyathia. Growing with erect stems 10 to 50 centimeters tall that are glabrous or sparsely hairy, it develops distinctive whorled leaves near the top of the plant. Its leaves are obovate to spoon-shaped, measuring 1 to 3 centimeters long, with finely toothed edges and a rounded or notched tip. The fruit is a smooth, spherical, lobed structure approximately 2.5 to 3 millimeters wide, containing flattened ovoid seeds with a delicate net-like surface.

Habitat: Disturbed areas

Bloom period: Apr-Jul

Elevation: < 200 m

Bioregions: n&ampc NCo, n&ampc NCoRO, SnFrB, CCo, SCo

California counties: San Francisco, San Mateo, Los Angeles, San Luis Obispo, Humboldt, Inyo, Contra Costa, Santa Cruz, San Diego, Yolo

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