Sisymbrium altissimum
Tumble mustard
Photo by Chez Brungraber
Family: Brassicaceae · Type: Herb · Not Native
Sisymbrium altissimum (Tumble mustard) is a non-native California herb in the Brassicaceae family, recognized by height, distal branching, and thread-like leaf segments.
Tumble mustard is a naturalized annual herb found in disturbed areas, fields, and pastures throughout California at elevations below 2,700 meters. Flowering from May to July, this plant produces pale yellow to white flowers about 6 to 8 millimeters long with distinctive horned sepals. Growing with extensively branched stems reaching 40 to 120 centimeters tall, it develops a complex, widely spreading growth habit. Its basal and lower stem leaves are pinnately lobed with 4 to 6 pairs of oblong to lanceolate lateral lobes, while upper leaves become finely dissected into thin, thread-like segments. The plant produces long linear fruits 6 to 9 centimeters in length, which contribute to its characteristic tumbling dispersal mechanism.
Identification and appearance
Key characters: 5 sympatric species; distinguished by height, distal branching, and thread-like leaf segments
Habitat and range
Habitat: Disturbed areas, fields, pastures
Elevation: < 2700 m
California counties: San Diego, San Bernardino, Los Angeles, Fresno, Inyo, Kern, Lake, Lassen, Merced, Modoc, Mono, Orange, Riverside, San Luis Obispo, Siskiyou, Tulare, San Benito, El Dorado, Monterey, Nevada, Plumas, Tuolumne, Ventura, Humboldt, Marin, Alpine, Sierra, Santa Barbara, San Francisco, Madera, Santa Cruz, Butte, Santa Clara, Del Norte, Yolo, Yuba, Placer, Shasta, Contra Costa, Imperial, Trinity, Kings, Sonoma, Mariposa, Colusa, Sacramento, Solano, Stanislaus
Outside California: North America, native to Europe
Bloom period
Sisymbrium altissimum blooms May-Jul.
How to tell it apart
vs Hirschfeldia: Sisymbrium pods are unsegmented; shortpod has segmented pods with beaded appearance.; vs Brassica: Sisymbrium pod valves have 3 veins; mustard pod valves have 1 vein.; vs Descurainia: Sisymbrium has undivided leaves on stem; tansy mustard has finely dissected feathery leaves.; vs Caulanthus: Sisymbrium petals are flat; jewelflower petals are crinkled or wavy.; vs Mutarda: Sisymbrium has 3-veined pod valves; check pod surface for vein count.
Frequently asked questions
Is Sisymbrium altissimum native to California?
No. Sisymbrium altissimum is not native to California (recorded as not native).
When does Sisymbrium altissimum bloom?
Sisymbrium altissimum blooms May-Jul.
Where in California does Sisymbrium altissimum grow?
Sisymbrium altissimum occurs in San Diego, San Bernardino, Los Angeles, Fresno, Inyo, Kern, Lake, Lassen and other counties, at elevations of < 2700 m.
What plant family does Sisymbrium altissimum belong to?
Sisymbrium altissimum is in the Brassicaceae family, genus Sisymbrium.
What habitat does Sisymbrium altissimum grow in?
Sisymbrium altissimum grows in Disturbed areas, fields, pastures.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.