Spurge

Spurge, common name for a large family of flowering plants that includes many with cactuslike growth forms, and for its representative genus. The family contains about 8000 species; it occurs primarily in the Tropics, but representatives are found throughout the world except in polar and mountainous areas. The plants range from small annual herbs to large trees. Members of this family often have milky latex, which in some species is irritating to the skin and can be fatal to livestock. Rubber is derived from the latex of several members of the spurge family, most importantly the para rubber tree. The floral whorl in the members of the family is usually inconspicuous, but the flowers are often grouped together in dense clusters, below which are borne large, colored leaves, or bracts, that serve the function of petals—that is, they attract pollinators. Poinsettia, found in Mexico, is an excellent example of a spurge with brightly colored bracts; it is a popular Christmas decoration. The castor bean, tung tree, and tallow tree are other important members of the family, producing commercially significant oils. The cassava, or manioc, tuber is rich in starch and is the source of tapioca. Recent DNA studies also place the parasitic plant rafflesia in the spurge family—a species of rafflesia known as the corpse lily produces a blossom up to 91 cm (36 in) wide, the largest flower in the world.

The spurge genus contains many common North American weeds. Several species have cactuslike growth forms with thick, succulent stems and no leaves. This growth form is an adaptation to hot, dry habitats and occurs in plant families as well. Spurges of this type can be distinguished from cacti by their milky latex.

Scientific classification: Spurges make up the family Euphorbiaceae. The representative genus is Euphorbia. The para rubber tree is classified as Hevea brasiliensis and the poinsettia as Euphorbia pulcherrima. The corpse lily is classified as Rafflesia arnoldii.