Boechera howellii
Howell's rockcress
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Family: Brassicaceae · Type: Perennial · Native
Boechera howellii (Howell's rockcress) is a native California perennial in the Brassicaceae family, recognized by few flowers, broad wavy fruits, and large seeds distinctive.
Howell's rockcress is a California native perennial found in the Sierra Nevada and high Cascade Range mountains on rock outcrops, talus slopes, and gravelly soil at elevations of 1,800 to 3,800 meters. Flowering from June to August, this plant produces white to pale purple flowers 4 to 8 millimeters long with delicate petals. Growing with slender stems 6 to 20 centimeters tall rising from a slightly woody caudex, it emerges from a basal rosette near ground level. Its basal leaves are narrow, 1 to 7 millimeters wide, with simple margin hairs and entirely glabrous leaf surfaces. The fruit is an ascending silique 2.5 to 6.5 centimeters long with slightly wavy edges, containing 10 to 20 seeds arranged in a single row.
Identification and appearance
Key characters: 28 sympatric species; few flowers, broad wavy fruits, and large seeds distinctive
Habitat and range
Habitat: Uncommon. Rock outcrops, talus slopes, gravelly soil, in alpine, subalpine habitats
Elevation: 1800-3800 m
California counties: Mono, Tulare, Fresno, Mariposa, El Dorado, Nevada, Madera, Siskiyou, Tuolumne, Inyo, Trinity, Placer, Alpine, Amador, Plumas, Shasta, Tehama
Outside California: Nevada, Oregon
Bloom period
Boechera howellii blooms Jun-Aug.
How to tell it apart
vs Arabis: Boechera pods hang downward or curve and are wider (2mm+); Arabis pods stand rigidly erect and are narrower.; vs Matthiola: Boechera has flattened pods; Matthiola has cylindrical pods and densely hairy gray-green foliage.; vs Streptanthus: Boechera petals narrow gradually without a claw; Streptanthus petals have a distinct narrow claw at base.; vs Penstemon: Boechera has four-petaled flowers and seed pods; Penstemon has tubular five-lobed flowers.; vs Caulanthus: Boechera is perennial with a woody base; Caulanthus is typically annual or biennial without a woody caudex.
Frequently asked questions
Is Boechera howellii native to California?
Yes. Boechera howellii is native to California (recorded as native).
When does Boechera howellii bloom?
Boechera howellii blooms Jun-Aug.
Where in California does Boechera howellii grow?
Boechera howellii occurs in Mono, Tulare, Fresno, Mariposa, El Dorado, Nevada, Madera, Siskiyou and other counties, at elevations of 1800-3800 m.
What plant family does Boechera howellii belong to?
Boechera howellii is in the Brassicaceae family, genus Boechera.
What habitat does Boechera howellii grow in?
Boechera howellii grows in Uncommon. Rock outcrops, talus slopes, gravelly soil, in alpine, subalpine habitats.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-09-30
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.