Euphorbia hirta or tawa-tawa is native to Central America. It is a very common weed of the tropics and subtropics. Also, it occurs throughout tropical Africa and also in South Africa. Euphorbia hirta (Tawa-tawa) has an infusion use as a cure for asthma and bronchitis. Therefore, it is famous as “Asthma Plant”.
Euphorbia comprises about 2000 species. It has a worldwide distribution, with at least 750 species in continental Africa. And, about 150 species in Madagascar and the Indian Ocean islands. This plant belongs to the annual, branched herb, prostrate to ascending, with branches up to 50 cm long. All parts are short-hairy and with sparse yellow hairs c. 1.5 mm long.
Its stems clothed in hairs produce a milky exudate when cut or broken.
Its leaf-blades about 25-50 x 11-26 mm, petioles about 2-4 mm long. Both the upper and lower surfaces of the leaf blade and the petioles clothed in hairs. Lateral veins 2-4 on each side of the midrib. Stipules linear, about 1.5-2 mm long, hairy.
The flowers in clusters are arrange in heads. Clusters consist of one female flower together with 1-7 male flowers. Each cluster surrounded by an involucre of 4 glands. Male flowers: Male flowers consist of a single anther and bract which is fimbriate at the apex. While, female flowers: Ovary green, about 1.1 mm diam., clothed in hairs.
Fruits are 3-lobed, about 1 x 1.1-1.2 mm, clothed in hairs. Seeds about 0.7-0.8 mm diam.
They say Euphorbia hirta (Tawa-tawa) is a cure for asthma and bronchitis. But how do some countries use this plant as medicine? First, in Nigeria, the Euporbhia Hirta are use in market purposes. Second, in Uganda, they are chewing the whole plant to induce labor during childbirth. Third, in Java and India, the tender shoots serve as a famine food, raw or steamed. But they may cause intestinal complaints. And, in West Africa, Euphorbia hirta is use as livestock fodder.