Melanoplus differentialis

The differential grasshopper (Melanoplus differentialis) is a species of grasshopper belonging to the genus Melanoplus found throughout northern Mexico, central United States and southern Ontario, Canada. It is considered a pest in most of its range. Adult males grow to 28–37 mm and females grow to 34–50 mm. They are brownish or greenish and as they age the color will darken. Some nymphs can be bright yellow. There are black grooves on the pronotum. The male has bootlike appendages at the end of its abdominal tip. There are inverted chevrons along the hind femur and the hind part the tibia is yellowish with black spikes. All of the adults tarsi are yellow along with its antennae, which in some cases are reddish yellow. Found throughout most of the United States except for the northwest. Within its range the M. differentialis is most often found in heavily weeded areas and grasslands, they can even be spotted in vacant lots and other urban areas. This species is not migratory but can travel within a few miles to search for food. An adult female lays up to 6 egg masses in soft soil, each of which can contain 40–200 eggs. The eggs begin embryonic development the summer they are laid, then enter diapause for the winter, to hatch over period of about two weeks in early summer of the next year. There is one generation per year. The nymphs take about 32 days from hatching to reach adulthood. Their development is well synchronized, and most nymphs transform to winged adults during a period of just a few days.Differential grasshoppers are polyphagous, eating both grasses and forbs, but experiments have shown that they grow faster if fed forbs. The most favored food plants tend to be giant ragweed (Ambrosia trifida), common sunflower (Helianthus annuus), and prickly lettuce (Lactuca serriola). Adults can detect a chemical change in wilted lettuce and sunflowers and will tend to avoid these plants. The young feed on various grains, alfalfa and hay crops, while the adults attack the corn, cotton and deciduous fruit crops. A single swarm can destroy a young crop in a few days. Because this species tends to feed in large swarms, it is a serious threat to farming in most of its range. In the northern part of the range it is about as numerous as the two-striped grasshopper (Melanoplus bivittatus) but it greatly outnumbers the two-striped grasshopper in the southern part of its range.