Producers should check grasshopper populations now

Thursday, June 5, 2014

Parts of Oklahoma that have suffered from a lack of rainfall are likely to experience grasshopper infestations the likes of a Biblical plague this summer.

“It’s just not the western parts of the state, there are pockets in eastern Oklahoma wherein the rain just has not fallen at the right time, even with recent rainfall in June,” said Tom Royer, Oklahoma State University Cooperative Extension entomologist. “Agricultural producers need to be taking proper preventative steps between now and July 1.”

Royer added waiting until a grasshopper sprouts wings makes effective control of the insects a “hit-and-miss” prospect, and a more expensive control endeavor at any rate.

“Be aware grasshoppers can eat 25 percent to 50 percent of their body weight in forage a day,” he said. “In contrast, a steer will eat 1.5 percent to 2 percent of its body weight in forage a day.”

Depending on the level of infestation, grasshoppers can have a significant negative effect on the health and availability of a producer’s pasture resources.

The first step is for producers to assess grasshopper population numbers on their properties. Royer suggests the producer study an area about one-square-yard in size as he or she walks through the pasture, counting the number of grasshoppers that jump out of the area as he or she passes. Repeat the process three or four times, leaving approximately 75 feet in between areas of study.

Once a producer has a sense of grasshopper population numbers, he or she should access OSU Extension Facts EPP-7196, “Grasshopper Management in Rangeland, Pastures and Crops,” available online at http://osufacts.okstate.edu.

“The fact sheet has easy-to-follow suggested treatment thresholds, as well as a discussion on Reduced Agent and Area Treatment options using Dimilin®,” Royer said.

Besiege® and Prevathon® are two relatively new insecticides registered for grasshopper control on rangeland and pastures. More information on these and other approved insecticides are available by consulting OSU Extension Current Report CR-7193, “Management of Insect Pests in Rangeland and Pasture.” The report is available online at http://osufacts.okstate.edu.