Contact: Mair Murray, Utah State University Extension Integrated Pest Management specialist, mair.murray@usu.edu
Last year it seemed that grasshoppers were everywhere in Utah, specifically in urban and residential areas. This year, populations will be high in some areas and lower in others, depending on spring weather conditions.
The reason for the variation starts beneath the surface – literally. Grasshoppers spend the winter as eggs in the soil. As temperatures warm in the spring, eggs start hatching into nymphs the size of a grain of rice. If conditions are cool and wet, these nymphs will drown in the rain or cannot feed. This May, several areas in northern Utah experienced a few heavy rains that may have dampened grasshopper populations, but in locations where conditions were warm and dry, the nymphs have been off and hopping.
Grasshoppers feed on almost any plant you can name, from grasses to small trees. Their chewing mandibles wreak havoc as they consume foliage, flowers, fruits, seed heads, and stems – essentially all above-ground plant parts. For the last several years, they have caused severe economic losses to farmers.
Consider these tips to help minimize grasshopper damage in the backyard or small farm.
- If you opt to use an insecticide to manage grasshoppers, apply treatment early while they are young. Nymphs are now visible in weedy or grassy areas along fence lines, roadsides, or any unmanaged area. Knowing where grasshopper nymphs are gathering and feeding is important because they are not yet very mobile, making them easier to control with insecticides. Once this vegetation dries, grasshoppers will move to farms and home gardens, so take advantage of the timing now when they are less mobile.
- A few insecticide options are available. EcoBran is a sawdust-like, attract-and-kill product that is spread on the ground or plants. Granular or sprayable options include an active ingredient such as bifenthrin, permethrin, or carbaryl for use in home gardens. Consult your local garden center about what products are available, and verify that the target crop and grasshoppers (or relatives) are listed on the label.
- Exclude grasshoppers from high-value crops by applying a row cover made from insect netting or a lightweight spun-bond material.
- Guinea hens, where appropriate, will ravenously feed on grasshoppers and leave the garden alone.
- As grasshoppers get older, remove them by hand in the evening or early morning, and place them in soapy water.
- Plant a border of grasses around high-value crops and keep the grass well-watered so grasshoppers will focus on this area rather than the garden.
- Natural predators such as birds, reptiles, mammals, and other arthropods feed on grasshoppers, but not enough to diminish damaging numbers.
For more information on grasshopper management, check out this fact sheet on grasshoppers, or see this video on grasshopper overview and management.
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