This pest is not limited to seedling stands but tends to be less troublesome on older stands. Fact Sheet No. Infestations of 2-3 caterpillars or cutworms per ft 2 . can be used as a general threshold. At that level of infestation, producers should monitor fields closely, identify the pests, and obtain exact counts for each species present. Grasshopper populations are normally highest around edges of fields near areas with tall weeds and grass.
Grasshoppers are always a problem when alfalfa is sod-seeded into grass pastures.
Frequently it is only necessary to spray border areas before they move into the interior of fields. Insecticide costs can be reduced by spraying only those portions of a field that have severe infestations.