The Heteropteran bugs include both plant-feeding and animal- feeding species, although the majority of them are vegetarians. They are, in general, somewhat larger than the homopterans and they do not usually form dense aggregations such as we find among the aphids and scale insects. The heteropterans start life as eggs, which are often extremely attractive when seen under a lens, and the nymphs then gradually develop into adults. Many species pass the winter in the egg stage, but others hibernate as nymphs or adults. There is often a marked difference in the colours of the adults before and after hibernation.
Several rather slender or oval green bugs occur in the garden, and these all belong to a large group known as mirids or capsids. Most of them are plant-feeders, but the black kneed capsid is omnivorous and it is an important ally of the gardener because it attacks the red spider mite. It is most often seen on apple trees. The common green capsid is also found on apple trees, but the two bugs are easily distinguished by their shapes and by the black "knees" of the first species, although the black markings are more readily seen in the nymphs. The common green capsid damages fruit trees and bushes of various kinds and is responsible for many of the brown scabs on apples. It passes the winter in the egg stage on the bark of trees.