Nature Education Knowledge (2011) 2(11: 3

Humans determine if an insect is beneficial, benign or pestiferous. Even when an insect is classified as a pest, it can have, under different circumstances, a beneficial role. A fly in a house is a pest, but that same fly is beneficial in its role as a detritivore. Termites are pests when invading homes, but are beneficial when fulfilling their ecological role in a forest.

Pests and Pollinators (full article)