Oxalis is a genus of wood-sorrels that belongs to the Oxalidaceae family and contains over 800 individual species of plants. Members of the Oxalis genus can be identified by their dense clusters of low growing foliage consisting of three or more notched leaflets. There are wild species of Oxalis growing in most regions of the world, many of which are cultivated as garden plants. Oxalis wood-sorrels are edible plants with a long history of culinary and medicinal use.
Wood-sorrels, sometimes recorded as wood sorrels or woodsorrels, are a family of perennials that look similar to common shamrocks. These types of wood-sorrel grow to a height of 6 inches (about 15 centimeters) and rapidly spread to form a lush ground cover on a forest floor. The most common species of Oxalis have numerous single leaves that consist of three evenly-shaped leaflets. There are also some species with leaves that have up to ten leaflets. Most of these wood-sorrels blossom in the mid to late spring with flowers that have five fused petals. The flowers of Oxalis wood-sorrels are usually white or yellow, but there are also species with pink or red flowers.
Some of the best known species of Oxalis include common wood sorrel and Bermuda buttercup. Common wood-sorrel (O. acetalis and O. montanta) is an attractive, high altitude wildflower that blossoms with simple, five-petaled white flowers with thin pink veins. Bermuda buttercup (O. pes-carprae) is a highly invasive wood-sorrel from Northern Africa with bright yellow flowers that has become a troublesome weed in North America and regions of Europe.
Oxalis wood-sorrels are recognized as an easily identifiable edible wild plant throughout the world and are cultivated for food in some regions. In the mountains of northern South America, Colombians cultivate a species of wood-sorrel that they refer to as oca (O. tuberosa) for a small tuber that is rich in carbohydrates. European and South American sailors have historically consumed different types of wood-sorrel as a source of Vitamin C.
These types of plants have also been gathered and cultivated for medicinal purposes. The leaves of these wood-sorrels contain a chemical compound called oxalic acid that cleanses the palate and satisfies hunger pangs when chewed. Practitioners of folk medicine used to extract salt crystals that they referred to as sorrel salt for various medicinal purposes. Sorrel salt is actually a form of calcium oxalate and is no longer used due to its role in the formation of kidney stones.
