Spurge Family

Spurges exhibit a wide range of growth forms. Most species are annual or perennial herbs, in the latter case dying back to the ground surface at the end of the growing season, but regenerating from roots and rhizomes at the beginning of the next growing season. Other species of spurges are shrubs and full-sized trees. Some species of spurges that grow in dry habitats have evolved morphologies that are remarkably similar to those of cacti (family Cactaceae). In some cases, the similarities between these families can be so great that many of the plants nonbotanists believed to be cacti are actually spurges.

When the stems or leaves of most species of spurges are wounded, they weep a white, milky substance known as latex. The latex of spurges can be used to manufacture a natural rubber. Natural rubber is a polymer in its simplest form, derived from a five-carbon compound known as isoprene, although much more complex polymers can also be synthesized. The specific, beneficial function of latex to wild plants has never been convincingly demonstrated, although this substance may be useful in sealing wounds, or in deterring the herbivores of these plants.

The individual flowers of spurges are usually rather small and unisexual. The latter characteristic can occur as separately sexed flowers occurring on the same plant (this is known as monoecious), or as different plants being entirely staminate or pistillate (dioecious). In many spurges, the individual flowers are aggregated together within a compact, composite structure known as a cyathium. In addition, most species of spurges have nectaries that secrete a sugary solution to attract insect pollinators. Some species' flowers are highlighted by specialized, highly colorful leaves, giving the overall impression of a single, large flower. The composite floral structure, nectaries, and brightly colored bracts of spurges are all adaptations that encourage visitations by the insect pollinators of these plants.