DALLAS -While crops and gardens suffer under the hot summer sun, grasshoppers thrive, eating more and growing faster, said a Texas Cooperative Extension expert.
“For a number of reasons, grasshoppers thrive under hot, dry conditions,” said Dr. Allen Knutson, Extension entomologist, Dallas.
And with little to find to eat in the pastures and dryland crop areas, home gardens or watered lawns look like an “an oasis” to them, Knutson said.
Grasshoppers lay their eggs along fence rows, ditches and pastures, he said.
“Eggs of different grasshopper species hatch out at different times, so young grasshoppers can be seen throughout the spring and early summer,” Knutson said.
Fungi are one of the main threats to grasshopper eggs. Hot, dry weather limits the growth of fungi and thereby results in a larger proportion of eggs hatching.
And grasshoppers just thrive in hot weather period, Knutson said. As insects are cold-blooded creatures, hot weather means their metabolism runs faster, so they eat more and grow faster.
Extension agents and personnel reported grasshoppers are pervasive throughout most of East Texas:
“We’ve got them bad,” said Diana Cantu, Extension office manager, Houston County. Cantu and her husband have 10 acres near Grapeland where they keep horses.
“Between the drought and the grasshoppers, we don’t have much left,” she said.
Cantu said grasshoppers also are invading Crockett and other towns.
In Polk County, to the south of Cantu, the situation is much different, said Mark Currie, Extension agent for agriculture.
“We’ve had a little more rain than some, and so the grasshoppers aren’t as bad,” he said. “To the north and west of us, it’s a different story.”
In Rusk County, Blaine Jernigan said they’ve “got plenty of grasshoppers.
“They’ve gone through a couple in instars (growth stages) and they seem to just be getting larger and larger,” he said.
In Wood County, some have been spraying for grasshoppers, said Clint Perkins, Extension agent for agriculture. Other people don’t have enough grass for the grasshoppers to eat to justify the cost of spraying.
Most of Panola County is relatively grasshopper free, said Doug McKinney, Extension agent for agriculture.
“The eastern part of the county received 6 to 7 inches of rain in June,” McKinney said. “Now the western part of the county, where I live, got less than 2 inches, so we have some grasshoppers. But it’s much worse to the west of us.”
Weed control in the fall and spring can reduce grasshoppers throughout the summer, Knutson said.
“Eliminating weeds will starve young hoppers and later discourage adults from laying eggs in the area,” he said.
But if there are already a lot of grasshoppers in the weedy areas, it’s not a good idea to spray or till.
“Destroying weeds infested with large numbers of grasshoppers can force the hungry grasshoppers to move to nearby crops or landscapes,” he said. “Control the grasshoppers in the weedy area first with insecticides or be ready to protect nearby crops if they become infested.”
“Floating row covers,” made of lightweight fabrics, can be used to protect vegetable gardens, flowers and small fruit trees, Knutson noted. The covers are the same type sold at home garden centers to protect landscape plants from freezing temperatures.
“These lightweight fabrics let sunlight in while protecting plants from insects,” he said.
There are a number of insecticides that will kill grasshoppers, Knutson said. Most pesticides, however, do not persist for more than a few days, and grasshoppers are likely to quickly re-infest a sprayed area.
The most successful treatment plan is to spray when the grasshoppers are small, he said.. The larger, more mature grasshoppers are harder to kill.
Some insecticides may be safe for home lawns but not for gardens, Knutson said.
Whether treating home landscapes, crops or gardens, he recommended homeowners and agricultural producers contact the Extension agent for agriculture and natural resources in their county.
Knutson also recommended the Extension bulletin L-5201: “Grasshoppers and Their Control,” which should be available at county Extension offices.