Trifolium columbinum
Olive clover
(c) Douglas Goldman, some rights reserved (CC BY-SA), uploaded by Douglas Goldman · licence
Family: Fabaceae · Type: Herb · Native
Trifolium columbinum (Olive clover) is a native California herb in the Fabaceae family, recognized by . Key features: spike-like inflorescence, plumose sepals.
Olive clover is a California native annual found in northern Coast Ranges, northern Sierra Nevada foothills, Central Valley, and San Francisco Bay Area in grassy slopes, valley meadows, and disturbed areas at elevations below 800 meters. Flowering from April to May, this plant produces distinctive two-colored flowers with purple and white petals in compact spikes 5 to 20 millimeters wide. Growing with ascending to erect hairy stems, it reaches modest heights with delicate branching. Its leaves have three leaflets, each 1 to 3 centimeters long, obovate in shape with fine serrated edges and lance-ovate stipules. The plant's flowers feature plumose calyces 8 to 14 millimeters long, significantly larger than the small 4 to 7 millimeter corolla.
Identification and appearance
Key characters: 53 sympatric species. Key features: spike-like inflorescence, plumose sepals
Habitat and range
Habitat: Grassy slopes, valley meadows, disturbed areas
Elevation: < 800 m
Bloom period
Trifolium columbinum blooms Apr-May.
How to tell it apart
vs Medicago: Trifolium flowers persist around fruits; Medicago flowers fall off leaving exposed coiled fruits.; vs Oxalis: Trifolium has pea-shaped flowers; wood-sorrels (Oxalis) have 5-petaled star-shaped flowers and heart-notched leaflets.; vs Melilotus: Trifolium flowers persist enclosing fruits; Melilotus flowers fall off leaving exposed ridged pods.; vs Castilleja: Trifolium has pea flowers and 3 toothed leaflets; paintbrush (Castilleja) has tubular flowers in colorful bracts.; vs Acmispon: Trifolium leaflets have toothed edges; Acmispon leaflets have smooth untoothed margins.
Frequently asked questions
Is Trifolium columbinum native to California?
Yes. Trifolium columbinum is native to California (recorded as native).
When does Trifolium columbinum bloom?
Trifolium columbinum blooms Apr-May.
What plant family does Trifolium columbinum belong to?
Trifolium columbinum is in the Fabaceae family, genus Trifolium.
What habitat does Trifolium columbinum grow in?
Trifolium columbinum grows in Grassy slopes, valley meadows, disturbed areas.
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.