Boechera koehleri
Koehler's rockcress
(c) Trevor Van Loon, some rights reserved (CC BY), uploaded by Trevor Van Loon · licence
Family: Brassicaceae · Type: Subshrub · Native
Conservation status: CNPS 1B.3
Boechera koehleri (Koehler's rockcress) is a native California subshrub in the Brassicaceae family, recognized by low elevation, persistent leaf bases, and large magenta flowers distinctive.
Koehler's rockcress is a rare (CNPS 1B.3) California native perennial found in the Klamath Ranges on rock outcrops at elevations of 100 to 1,000 meters. Flowering from April to May, this plant produces purple to magenta flowers 8 to 12 millimeters long with petals 2.5 to 4 millimeters wide. Growing 8 to 45 centimeters tall with a woody caudex and stems emerging from a basal rosette, it features stems with short-stalked, 2 to 4-rayed hairs near the base. Its basal leaves are narrow, 1 to 3 millimeters wide, with short-stalked, multi-rayed hairs, while cauline leaves range from 3 to 30 with glabrous distal surfaces. The fruit is spreading-ascending, 5 to 7.5 centimeters long and 1.8 to 2.5 millimeters wide, containing 58 to 94 seeds in a single row.
Identification and appearance
Key characters: 13 sympatric species; low elevation, persistent leaf bases, and large magenta flowers distinctive
Habitat and range
Habitat: rock outcrops
Elevation: 100-1000 m
California counties: Del Norte, Trinity
Outside California: southern Oregon
Bloom period
Boechera koehleri blooms Apr-May.
Conservation status
CNPS 1B.3
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 koehleri native to California?
Yes. Boechera koehleri is native to California (recorded as native).
When does Boechera koehleri bloom?
Boechera koehleri blooms Apr-May.
Where in California does Boechera koehleri grow?
Boechera koehleri occurs in Del Norte, Trinity, at elevations of 100-1000 m.
What plant family does Boechera koehleri belong to?
Boechera koehleri is in the Brassicaceae family, genus Boechera.
Is Boechera koehleri rare or endangered?
Boechera koehleri carries California Rare Plant Rank 1B.3, state rank S3.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CNPS Rare Plant Inventory · Index of California Plant Names · CalPhotos · CDFW CNDDB
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.