It can prevent feeding by some species, in other cases it affects insects that consume foliage that has been sprayed with the product. These products are distributed in Montana by the Wilbur-Ellis Co., the only source of which I am aware. Insecticidal soaps containing pyrethrins can kill some species of grasshopper if they are sprayed directly on the insects. Many beneficial insects, such as ladybugs, are also killed by insecticidal soaps, so selective application is a good idea. Insecticidal soaps are a least-toxic alternative, but are not as effective as other chemical controls and have no residual effect.
Baits containing the insecticide carbaryl can be fairly effective.
To use these baits, spread an 8-foot border around areas needing protection, or two narrower borders about 8 feet apart. Be aware that any animal or insect that picks up the bait could also be affected. Baits can also be carried by rain or sprinklers into nearby streams or ponds. Although carbaryl is of fairly low toxicity, children, pets, birds, and wildlife should be considered when selecting this method of grasshopper control. Long-term management tactics should encourage the natural predators of grasshoppers as much as possible.