Oxalis pes-caprae

Oxalis pes-caprae_buttercup oxalis_ JM Di Tomaso
Photo: Joseph DiTomaso

Common names: Bermuda buttercup; buttercup oxalis; sour grass

Oxalis pes-caprae (buttercup oxalis, Bermuda buttercup, yellow oxalis) is a low-growing perennial (family Oxalidaceae) found along the coast of California, in the Coastal Ranges, and in the Sacramento Valley. Buttercup oxalis occurs in coastal dunes, scrub, oak woodlands, gardens, turf, urban areas, orchards and agricultural fields. Buttercup oxalis was introduced as an ornamental landscape plant from South Africa. Although buttercup oxalis does not produce seeds, it is difficult to control because of its ability to form many persistent bulbs. Cultivation may be an effective control if carried out when the plants are just beginning to flower.

Cal-IPC Rating: Moderate?

CDFA Rating: None?


Plant Assessment Form - Information gathered by Cal-IPC on the impacts, rate of spread, and distribution of invasive plants in California. Does not include management information.

Weed Management Notes

  • Management Notes - Information on management techniques and effectiveness from the University of California Cooperative Extension’s Weed Research & Information Center.

Cal-IPC Newsletter Articles

Cal-IPC Symposium Presentations

Presentations are linked where available. Where a presentation is not available, find more information by reading the abstract in the Cal-IPC Symposia Archive.

Other Oxalis pes-caprae Information

  • Bugwood - National database from the Center for Invasive Species and Ecosystem Health at the University of Georgia.
  • CalPhotos - Images of plants taken mostly in California.
  • Calflora - Distribution map and records of this species in California.
  • CalWeedMapper - Distribution map of this species in California with ability to determine regional priorities.
  • EDDMapS - Distribution of this species in North America.
  • Jepson Interchange - Information on this plant's taxonomy, biology, and distribution from UC Berkeley's Jepson Herbarium.
  • USDA PLANTS Database - Information on identification and distribution, with links to websites in individual states.
  • Additional photos

    Oxalis pes-caprae_flowers_copyright2019_NealKramer
    Oxalis pes-caprae (Bermuda buttercup) flowers. Photo: &#169 2019 Neal Kramer
    Oxalis-pes-caprae (Bermuda buttercup) leaf. Photo: Ron Vanderhoff
    Oxalis pes-caprae_infestation_copyright2007_NealKramer
    Oxalis pes-caprae (Bermuda buttercup) infestation. Photo: &#169 2007 Neal Kramer