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.
The female can lay an average of 200 eggs during a single season. Under favorable conditions up to 400 eggs can be laid. Approximately 40 eggs can be laid even if unfavorable conditions exist. The egg pods are very resistant to moisture and cold and are affected very little by winter conditions if the soil is not disturbed. They are also laid in cropped areas including late season crops, weedy fields, hay fields and alfalfa.