Significance

Many species of Hemiptera are significant pests of crops and gardens, including many species of aphid and various scale insects, including the cottony cushion scale, a pest whose infestation of American citrus crops sparked one of the earliest biological pest control programmes, when the Australian beetle Rodolia cardinalis was introduced as a natural enemy of the scale insect.

Conversely, some predatory hemipterans are themselves biological pest control agents, such as various nabids, and even some members of families that are primarily phytophagous, such as the genus Geocoris in the family Lygaeidae. Other hemipterans have positive uses, such as in the production of the dyestuffs cochineal and crimson, or shellac.