Aphid, or Plant Louse, a small insect that destroys crops and
ornamental plants. Most aphids are green, red, or brown; some
are gray, yellow, black, or pink. Nearly all aphids are less
than 0.2 inch (6 mm) long. Their bodies are soft, and their legs
are slender and weak. Some adults have two pairs of weak wings.
The aphidThe aphid , or plant louse, is a tiny, soft-bodied
insect that feeds on plant juices.  Many aphids are named for
the plants they destroy; for example, cotton aphid and apple
aphid. Aphids damage plants by sucking the juices from buds,
leaves, and shoots or from the roots. They exude a sugary liquid
called honeydew, which sticks to the plant and causes the growth
of various harmful fungi and molds. Some kinds of aphids cause
the formation of galls (small swellings) on plants. Aphids can
also spread plant diseases.  Ants play an important role in the
destruction caused by aphids. Certain species of ants protect
aphids from enemies, shelter them from bad weather, tend their
eggs, and carry them