There's a menace hopping toward your yard. It has four legs, big eyes and antennae.
Grasshoppers are typically more of a rural problem. But with a drought in full swing, the hungry insects are flying to the city.
“We're seeing pockets of them,” Oklahoma State University entomologist Tom Royer said. “The places where you're most likely to see them are places like Guthrie where you have a town that is surrounded by agriculture. They're being pulled in to look for food.”
Oklahoma's grasshopper population is down this year, according to the United States Department of Agriculture. Researchers think it's because the hot weather has dried up food sources.
The USDA studied populations from Ardmore to the tip of the Panhandle using about 450 traps. The traps are set for grasshoppers every few square yards. Most years there are 12 to 15 grasshoppers per yard; this year there were two or three per yard and some traps were empty, USDA state plant health director Blaine Powell said.
“It's the lowest count I've seen in 20 years,” Powell said. “The drought had something to do with it, but you can't blame it all on the high temps. Really it comes down to the timing of the hatch not being conducive to large populations.”
The goal of the study is to predict future populations, Powell said. Grasshoppers that eat garden vegetables are a nuisance for urban dwellers, but farmers and ranchers have the most to lose.
“They compete with cattle for forage,” Powell said. “If we have an explosion in the population, it's something people will want to know about before it actually happens.”
Grasshoppers on the move
With their traditional rangeland habitat offering little in the way of food and water, Royer expects that populations will branch out.
“I think we'll continue to see them moving into these more populated areas where people are watering their yards,” Royer said. “They're mostly going to be a problem for people who keep gardens. They're going to continue to search for food and water, and they'll continue to look for areas to lay their eggs.”
Oklahoma has more than 130 species of grasshoppers. Most are capable of eating 50 percent of their body weight each day. The differential grasshopper and the two-striped species are the most likely to cause problems.
Grasshoppers like broad-leaved plants and grass. A general rule of thumb is anything that's green is at risk to become breakfast, lunch and dinner.
“It's a problem if they're in your yard,” OSU extension educator Ray Ridlen said. “They can be pretty devastating.”
How to fight them
Ridlen said it's usually impossible to spray every plant in your yard, but recommends creating a 10 to 15 foot perimeter around your property using an insecticide. Ridlen recommends Sevin as an effective insecticide, though a number of products will work.
Generally insecticides are more effective on smaller grasshoppers. Insecticides can also break down in heat and sunlight, meaning they have to be applied about every 24 hours or so in some cases.
If grasshoppers do infest your garden or flower bed, finding the locations of their hatching sites can be helpful. Some plants can be protected by floating row covers that allow in air and sunlight but not grasshoppers. The best advice is to remain aggressive.
“Once they've found that little oasis in the desert, they won't want to leave,” Ridlen said.