Aphids are small, soft-bodied insects with long, slender mouth parts with which they pierce stems, leaves, and other tender plant parts to suck out plant fluids. Almost every plant has one or more aphid species, which occasionally feed on it. Many aphid species are difficult to distinguish from one another; however, identification to species is not necessary to control aphids in most situations. Aphids may be green, yellow, brown, red or black depending on the species and the plants they feed on. A few species appear waxy or woolly due to the secretion of a waxy white or gray substance over their body surface. All are small, pear-shaped insects with long legs and antennae. Adult aphids are generally wingless, but most species also occur in winged forms, especially when populations are high or during spring and fall. The ability to produce winged individuals provides the pest with a way to disperse to other plants when the food source gets scarce. Left untreated, Aphids can cause serious damage to ornamental plants.