Cnidoscolus aconitifolius, commonly known as chaya, tree spinach, or spinach tree, is a large, fast-growing and leafy perennial shrub that is believed to have originated in the Yucatán Peninsula of Mexico. The specific epithet, aconitifolius, means "Aconitum-like leaves". It has succulent stems that exude a milky sap when cut. The plant can grow to be tall, but usually is pruned to approximately for easier leaf harvest. It is a popular leaf vegetable in Mexican and Central American cuisines, similar to spinach. White flowers are born on a terminal panicle held high above the foliage. The leaves should be cooked before being eaten, as the raw leaves contain a high content of toxic hydrocyanic acid. Up to five raw leaves can be eaten a day. To be eaten safely, the required cooking time is 5–15 minutes, with 20 minutes being recommended most often in recipes, and it should not be cooked in aluminium cookware. Taxonomy Cnidoscolus aconitifolius subsp. aconitifolius is found from northern Mexico to Guatemala and is cultivated as far south as Peru, while Cnidoscolus aconitifolius subsp. polyanthus (Pax and K.Hoffm.) Breckon is restricted to a small area in western Mexico. Plants in the Chayamansa group (syn. Cnidoscolus chayamansa) are the most widely cultivated, because they lack stinging hairs on the leaves. It is divided into four cultivars, based on leaf morphology: 'Chayamansa' (most common), 'Estrella', 'Picuda', and 'Redonda'. Cultivation Chaya is easy to grow and it suffers little insect damage. It may be a tender perennial in the United States, but persists in climates such as Florida. It is tolerant of heavy rain and has some drought tolerance. Propagation is normally by woody stem cuttings about 6-12 inches long, as seeds are produced only rarely. Early growth is slow as roots are slow to develop on the cuttings, so leaves are not harvested until the second year. Thereafter, Chaya leaves may be harvested continuously so long as no more than 50% of the leaves are removed from the plant, in order to guarantee healthy new plant growth. A USDA study in Puerto Rico reported that higher yields of greens could be obtained with Chaya than any other vegetable they had studied. In another study Chaya leaves were found to contain substantially greater amounts of nutrients than spinach leaves. The numerous white flowers of the plants attract butterflies. Consumption Some varieties have stinging hairs and require gloves for harvesting. Cooking