Pest Management Options:  Grasshopper Control

Grasshopper life stages
Grasshoppers molt 5 times to reach the adult, winged stage.

Springtime, while grasshoppers are still nymphs, is the best time for suppressing grasshopper populations. Treating as wide an area as possible is the key to success. When grasshoppers become adults, they can travel great distances and may not remain in one area long enough for an insecticide to be effective.

Treat open fields, roadsides, hedgerows, drainage ditches, and other weedy areas. Some options include:

Bait + insecticide

  • wheat bran + carbaryl or Nosema locustae (a natural grasshopper pathogen) that must be consumed
  • spread evenly through the habitat, grasshoppers eat the bait as they are foraging for food
  • easy to apply, but expensive
  • selectively kills only grasshoppers and other foraging insects
  • must be reapplied frequently and immediately following wetting events (rain, sprinkler irrigation)
  • very effective option

Dust

  • easy to apply, but expensive
  • does not readily adhere to foliage and must be reapplied frequently

Sprays (malathion, carbaryl, diflubenzuron)

  • less expensive
  • adheres to plant material
  • malathion and carbaryl kill on contact, or when grasshoppers eat foliage
  • diflubenzuron must be ingested and is slower to kill

Sometimes the state department of agriculture will subsidize or coordinate grasshopper spray programs in severe grasshopper years. USDA-APHIS is responsible for control programs on public lands. When grasshoppers occur at high numbers, state and federal aid may be available in planning and conducting a Cooperative Rangeland Grasshopper Management Program.