- Oxalis pes-caprae is a small perennial herb in the Oxalidaceae (Oxalis family), native to the Cape Region of South Africa. Shoots of O. pes-caprae arise from a short vertical stem that is attached to a pale brown underground bulb. Each bulb (usually smaller than 1 in. [2.5 cm] in size) is capable of producing over 20 small whitish bulblets each year.
- The trifoliate (clover-like) leaves arise from an enlarged basal stem tip, and are arranged in a loose basal rosette. Petioles are usually less than 4.7 in. (12 cm) long. Each leaflet measures less than 1.4 in. (3.5 cm) in length and are often spotted with hairy lower surfaces.
- Flowers of O. pes-caprae are bright yellow and are arranged in umbel-like inflorescences. These inflorescences generally have fewer than 20 flowers each, with peduncles shorter than 11.8 in. (30 cm) in height. Sepals of O. pes-caprae are green, less than 0.28 in. (7 mm) long, lanceolate to oblong in shape, and the tips often have two orange or yellow tubercles. The yellow petals are clawed, less than 1 in. (2.5 cm) in length. Each flower has 10 stamens.
- In North America, O. pes-caprae generally flowers from late fall to early summer, but fruits and viable seed have not been observed in California.
- Ecological Threat
- Oxalis pes-caprae, although widespread as a garden weed throughout much of California, has never before been observed invading natural areas in North America. It is now reported as invading native coastal dunes in northern California. Due to its extensive occurrence in lawns and gardens, O. pes-caprae has the potential to rapidly spread via the production of bulblets and contaminated soils into adjacent natural areas in California and elsewhere.