Oxalis pes-caprae

Oxalis pes-caprae_buttercup oxalis_ JM Di Tomaso
Photo courtesy 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.

Rating: Moderate

Cal-IPC Resources

  • 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.
  • CalWeedMapper - Statewide maps, climate models, and reports.
  • Cal-IPC News - Our quarterly newsletter. Each issue is available as a pdf.
  • Cal-IPC Symposium Proceedings - Presentations and papers from our annual Symposium.
  • Don't Plant a Pest! - Select your region to find non-invasive alternatives to ornamental species. Also see our statewide brochure on trees.

    Other Resources

    Symposium Presentations

    • Stringer, L. and M. Heath (2011). Comparison of four herbicide treatments on Oxalis pes-caprae. Cal-IPC 2011 Symposium. Tahoe City, CA, California Invasive Plant Council.
    • Giessow, J. and P. Zedler (1996). The effects of fire frequency and firebreaks on the abundance and species richness of exotic plant species in coastal sage scrub. California Exotic Pest Plant Council Symposium '96. San Diego, CA.

    Cal-IPC News Articles

    • Albert, M. E. (1995). Portrait of an invader II: The ecology and management of Carpobrotus edulis. CalEPPC News. 3: 4-6.
    • Sigg, J. (2003). Oxalis pes-caprae. CalEPPC News. 11: 8-9.