Brassica nigra

Black mustard

Family: Brassicaceae · Type: annual · Not Native

Conservation status: Cal-IPC Yes

Black mustard is a naturalized annual found in California's Central Valley and Foothills in disturbed areas and fields at elevations below 1,500 meters. Flowering from April to September, this plant produces bright yellow flowers 7 to 11 millimeters long with petals 3 to 4.5 millimeters wide. Growing 3 to 6.5 feet tall with generally branched stems that have sparse to dense stiff hairs, especially on lower parts. Its leaves are pinnately lobed with serrated edges, with basal leaves larger and cauline leaves becoming progressively smaller and sessile toward the stem tips. The fruit develops as an erect, slender pod 1 to 2.5 centimeters long with a terminal seedless segment.

Habitat: Common. Disturbed areas, fields

Bloom period: Apr-Sep

Elevation: < 1500 m

Bioregions: CA-FP

California counties: Riverside, Los Angeles, San Bernardino, Orange, San Diego, Ventura, Monterey, San Luis Obispo, San Mateo, Tulare, Yolo, Lake, San Joaquin, Alameda, Santa Clara, Fresno, Santa Barbara, Kern, Sonoma, Butte, Mendocino, Solano, Tuolumne, Santa Cruz, San Francisco, Colusa, Marin, Siskiyou, San Benito, Sutter, Contra Costa, Sacramento, Humboldt, Glenn, El Dorado, Mariposa, Napa, Stanislaus, Nevada, Amador, Placer, Imperial, Inyo

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