Lathyrus rigidus
Rigid pea
(c) James H. Thomas, some rights reserved (CC BY) · licence
Family: Fabaceae · Type: Vine · Native
Conservation status: CNPS 2B.2
Lathyrus rigidus (Rigid pea) is a native California vine in the Fabaceae family, recognized by erect clustered stems and sagebrush habitat diagnostic.
Rigid pea is a California native perennial ranked 2B.2 by CNPS, found in Modoc County in sagebrush scrub and disturbed areas at elevations of 800 to 1,200 meters. Flowering from April to July, this plant produces white to pink flowers 17 to 23 millimeters long in dense clusters of 2 to 5 blooms. Growing with multiple erect, clustered stems that are distinctively angled or flanged, it reaches moderate heights with a clumped growth pattern. Its leaves feature 6 to 10 narrow leaflets, each 1 to 3 centimeters long, ranging from lanceolate to elliptic, with slender bristle-like tendrils. The plant produces glabrous fruits, completing its distinctive structural profile.
Identification and appearance
Key characters: 3 sympatric species; erect clustered stems and sagebrush habitat diagnostic
Habitat and range
Habitat: Sagebrush scrub, disturbed areas
Elevation: 800-1200 m
California counties: Modoc, Del Norte
Outside California: to Oregon, Idaho, Nevada
Bloom period
Lathyrus rigidus blooms Apr-Jul.
Conservation status
CNPS 2B.2
How to tell it apart
vs Vicia: Lathyrus style is flattened with hairs on top only; Vicia style is round and hairy all around.; vs Pickeringia: Lathyrus has tendrils and compound leaves; Pickeringia is a spiny shrub with simple leaves.; vs Pisum: Lathyrus has small normal stipules; Pisum has giant leafy stipules larger than leaflets.; vs Lupinus: Lathyrus has two leaflets and tendrils; Lupinus has palmate leaves with no tendrils.; vs Hosackia: Lathyrus has exactly two leaflets and tendrils; Hosackia has 3-9 leaflets with no tendrils.
Frequently asked questions
Is Lathyrus rigidus native to California?
Yes. Lathyrus rigidus is native to California (recorded as native).
When does Lathyrus rigidus bloom?
Lathyrus rigidus blooms Apr-Jul.
Where in California does Lathyrus rigidus grow?
Lathyrus rigidus occurs in Modoc, Del Norte, at elevations of 800-1200 m.
What plant family does Lathyrus rigidus belong to?
Lathyrus rigidus is in the Fabaceae family, genus Lathyrus.
Is Lathyrus rigidus rare or endangered?
Lathyrus rigidus carries California Rare Plant Rank 2B.2, state rank S2.
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.