About Oxalis pusilla Jacq.
Oxalis pusilla Jacq. has a narrow, creeping stem that roots easily at its nodes. Its leaves are trifoliate, made up of three rounded leaflets that look similar to clover. Some varieties have green leaves, while others, such as Oxalis corniculata var. atropurpurea, have purple leaves. Inconspicuous stipules grow at the base of each petiole. Its small yellow flowers have petals that are either round-edged or sharp-ended. The flowers close when the plant is not in direct sunlight, which gives it the nickname "sleeping beauty". Individual specimens can produce anywhere from one to over 20 flowers. The fruit is a narrow, cylindrical capsule 1–2 cm (0.4–0.8 in) long, notable for explosively discharging its contained seeds, which are 1 mm (0.04 in) long. Its pollen is approximately 34 microns in diameter. This species is thought to originate from southeastern Asia. It was first formally described by Linnaeus in 1753 from specimens collected in Italy, and appears to have been introduced to Italy from eastern regions before 1500. Today it has a cosmopolitan distribution, and is often classified as a weed in gardens, agricultural fields, and lawns. The leaves of Oxalis pusilla Jacq. are edible, with a tangy, lemon-like taste. A drink can be prepared by infusing the leaves in hot water for around 10 minutes, adding sweetener, and then chilling the mixture. The whole plant is high in vitamin C. All woodsorrels are safe for consumption in low doses, but eating large quantities over an extended period of time can interfere with the body's calcium absorption. Indigenous peoples of Taiwan commonly cultivate this plant, which they refer to roughly as p-r-səʔ, to treat snakebites and scabies.
