Wyoming

Photographic models in a new University of Wyoming book don't strut down the runway displaying the latest fashions. Instead, they hop around the state's agricultural fields and native rangelands gobbling up huge amounts of forage.

A team of insect and plant experts have prepared a new field guide titled Common Wyoming Pest Grasshoppers. The book is available free of charge from the UW Cooperative Extension Service.

"There are 112 or so species of grasshoppers in Wyoming, but only some of them are serious pests," says one of the authors, Alexandre Latchininsky, an assistant professor and Extension entomologist in the UW College of Agriculture.

"This book covers 17 of the most important economic species in terms of rangeland and crop pests. It describes their nymph and adult stages in a simple way, and with photos it should allow for easy identification of these species by non-specialists," Latchininsky says.

"As such, the primary target audience for the book includes weed and pest control personnel around the state, farmers, ranchers, land managers, homeowners, and scouts with the U.S. Department of Agriculture's Animal and Plant Health Inspection Service (APHIS)," he adds.

Co-authors are Scott Schell, an assistant Extension entomologist in the College of Agriculture, and Bruce Shambaugh, plant health director for the Wyoming office of APHIS-Plant Protection and Quarantine.

The handbook states that in areas where grasshopper populations are at damaging levels, it is useful to know what species are present. The authors emphasize that not all species are susceptible to all control measures, and some of the species pose no threat to broadleaf crops.

Latchininsky says the most common hopper in the state is the migratory grasshopper, which can cause serious damage to both crops and native rangelands. In one year, an observed population went from three to 30 adults per square yard, and this species can reach densities of more than 100 per square yard in succeeding years.

The most troublesome area for grasshoppers is Goshen and Platte counties.

"There are large areas of native rangelands, and historically these areas are most susceptible to grasshopper outbreaks," Latchininsky says. "The most common grasshoppers in this part of the state are the whitewhiskered, bigheaded and twostriped."

In western Wyoming, the most prevalent species is the clearwinged. It mostly attacks irrigated pastures and hayfields, and it has caused significant damage in Fremont County, Latchininsky notes.

Other hot spots for hoppers are northeastern Wyoming including the counties of Niobrara and Weston.

In 2002, large areas of rangeland in Fremont, Goshen, and Niobrara counties were infested with hoppers.

"The grasshopper damage and drought combined left very little forage for livestock," says Schell, who helped organize public meetings in the three counties to discuss new control methods.

"Ranchers who needed to control grasshoppers were able to use the latest technique (Reduced Agent and Area Treatments) rather than traditional, blanket aerial spraying of infestations," he says. "The ranchers saved over $1 per area in protecting approximately 400,000 acres. They now know that outbreaks can be economically controlled with minimum adverse environmental impact."

Schell and Latchininsky, along with other experts, will lead grasshopper management seminars this spring around the region.

"We'll be distributing our books during these workshops," says Latchininsky, who notes the guides are printed in waterproof stock in a "pocket format" specifically for field work.

Copies of the book can be obtained by e-mailing the College of Agriculture's Resource Center at bixby@uwyo.edu, calling the center at (307) 766-2115, or writing to the University of Wyoming, College of Agriculture, Department 3313, 1000 E. University Ave., Laramie, WY 82071.

Date: 4/18/05