Cropdusters

3 clues
Some small planes
Flying sprayers on farms
Agricultural aircraft (1)
Similar answers:
Adbusters
Balusters
Blockbusters
Blockofbusters
Blusters
Busters
Bustersbluster
Bustersghost
Claimsadjusters
Clusters
Comeonlikegangbusters
Cropdogfieldcob
Cropdust
Cropduster
Cropdusters
Custers
Custerscluster
Custersiststand
Custerslastsit
Custerslaststand