Purdue University
Agricultural Extension Service
Department of Entomology
Mimeo E-19
October 1961
Grasshopper Control
Grasshoppers are general feeders. They attack both natural vegetation and cultivated crops. In Indiana, they are especially destructive to grasses, com, sorghum, clover, alfalfa, soybeans, vegetables, young fruit trees, nursery stock and flowers.
Grasshopper populations vary from year to year. They cause the most damage in years when high populations are coupled with dry weather. Drought conditions reduce natural vegetation and cause the insects to move into cultivated crops.
Life Cycle
Grasshopper eggs are laid in the soil during the fall. Preferred egg laying sites include roadsides, ditch banks, fence rows, clover fields and alfalfa fields. The eggs hatch in June, and the tiny grasshoppers may feed for 2 or 3 weeks without being noticed. Later, they start to move about and may attack nearby crops. There is one generation each year.
Methods of Control
Grasshoppers are not difficult to control with any one of several insecticides. These are listed in Table 1 on the following page. Pasture and harvest restrictions and other information contained in the table will enable the user to select a chemical that meets his particular need. The amount of material required per acre should be mixed with enough water for even distribution. Malathion has a short residual effect, and a repeat application may be necessary. It is the only material listed that can legally be used on pastures and forages crops for dairy cattle feed.
Where and How to Spray
Grasshoppers are best controlled early in the season while they are still confined in fence rows and other hatching sites. The small insects are also much easier to kill, and spraying of such areas may eliminate the problem of chemical residues on crops to be harvested or pastured. In this connection, border spraying around fields to be protected is often effective in stopping migrations.
Control in Home Gardens
Any of the materials listed in Table 1 for farm crop spraying can be used to protect flowers and other non-edible plants. Garden supply stores and other dealers usually have them available in small packages. When spraying vegetables, it is important to check the label to determine crops on which the insecticide can safely be used. Border spraying of weeds and fence rows around a home garden will often give effective control.
In addition to the insecticides listed, chlordane is also readily available in small packages. It can be used as a 5 percent dust or as a spray by diluting a 45 percent emulsifiable concentrate with water, according to directions on the package. As with all insecticides, label precautions should be observed carefully.