Landscape Pests

Grasshoppers are Making People Hopping Mad in 2002!!

Written by Extension Agent Nathan Riggs, Bexar County Extension

Homemade Grasshopper Bait Recipe

Grasshoppers and Texas go hand in hand, especially during the summer. Lately, it seems like local grasshopper populations are quite a bit ahead of schedule. This week's article from the Bexar County Extension office was inspired by an increasing number of phone calls and personal observations pertaining to grasshopper populations in the South Texas Area. Infestation map courtesy of Dr. James Robinson, District Entomologist, Texas Cooperative Extension, Overton, TX.

Grasshopper eggs are laid in sandy or loose soils in the fall of the year and usually begin to hatch in late March or April of the following spring. In 2002, grasshopper eggs began hatching in early March and even late February! Immature grasshoppers take three to four weeks to grow to the adult stage and develop wings. In general, grasshoppers feed on broadleaf plants and grasses of all types. They also feed on fruits and the tender leaves of trees.

There are many species of local grasshoppers ranging in size from one-inch to four inches in length. The most prominent species are the Differential grasshopper, Red-legged grasshopper and the Two-striped grasshopper (all shown below). In high enough numbers, any species of grasshopper can cause damage to ornamentals, orchards and pastures in a relatively short period of time, so more often than not, areas are innundated with grasshopper populations so dense that few things can be done to successfully control the problem.

The only way to truly "control"grasshoppers is by treating areas of at least 100 acres at a time. For the average lawn of less than one acre on up to five areas or more in rural situations, treatments may only last for two or three days.

What treatments are available? First of all, as grasshoppers are hatching in the spring, a biological product called Nolo Bait is available. It contains a protozoan pathogen that is very effective on young grasshoppers. Once grasshoppers are more than 7 to 10 days old, this bait no longer works. A couple of insecticide products on the market are good for rangeland and lawn situations. Liquid Sevin (carbaryl), malathion or pyrethrins will provide three to five days of suppression before new grasshoppers begin to enter the treated area. Check the labels for each of these products if they are to be applied to grazed or hayed areas. Grazing or hay harvest restrictions may be in affect. General use lawn sprays will kill grasshoppers as well. Granular insecticides generally do not fare well on grasshoppers.

Differential Grasshopper

Red-Legged Grasshopper

Two-Striped Grasshopper

To protect individual plants, consider using gro-web cloth over the plant to prevent access to the plant by the grasshoppers.

To tie all of this together, consider this: the absolute favorite weather conditions for grasshoppers are temperature above 95 degrees F and extremely dry. Our lack of rainfall this spring has played a definite role in increasing grasshopper numbers to say the least. As summer approaches, pray for rain; not only for obvious reasons, but because it seems to help us with grasshoppers as well. Check out Texas Extension Publication L-5201 on Grasshoppers and Their Control for more information as well.