They are primarily weed feeders, but will readily move into cultivated crops. Packard grasshopper, Melanoplus packardii . They prefer sandy soils with light grass cover. They are the least damaging of the species named in this publication, but can be a problem in both grassland and cultivated crops. These insects cause some damage every year, but become very destructive during outbreak periods.
Weather is the main factor affecting grasshopper populations.
Outbreaks are usually preceded by several years of hot, dry summers and warm autumns. Dry weather increases nymph and adult survival. Warm autumns allow grasshoppers more time to feed and lay eggs. Cool, wet weather slows nymphal development, reduces the number of eggs laid, and increases the incidence of diseases. Grasshoppers have a high reproductive capacity.