Published on 12/02/98

Cereal Leaf Beetles Newest Worry for Georgia Farmers

Georgia's wheat and grain farmers have one more thing to worry about. Cereal leaf beetles are moving across the state.

These little beetles eat the leaves in small grains and can eat about 15 percent of the crop yield. Fortunately for Georgia farmers, it's not that bad yet.

"We first found cereal leaf beetles north of Rome in 1989. And in that area, it's causing problems," said David Buntin, a University of Georgia entomologist at the Georgia Experiment Station in Griffin. "Now we're finding them across the state. And as the populations grow, they're causing more damage."

Buntin said the beetles are moving at about 50 miles a year across Georgia. Once they're spotted, it takes five to six years for the numbers to increase to the point of causing substantial damage.

"Within another 10 years, cereal leaf beetles will be pretty much everywhere in the state at levels where, if you're growing wheat, it's something you'll have to look out for," Buntin said.

Cereal leaf beetles came into the United States from Europe in the early 1960s. They were first introduced in the Great Lakes area. The beetles eat almost any small grain, including wheat, oats and barley. Their feeding damages the leaves and cuts yields. Adult beetles will also feed on corn leaves. But they don't usually hurt corn yields.

"Wheat is a marginal-profit crop here," Buntin said. "And this is one more pest farmers have to scout for and treat." Georgia farmers can grow wheat in rotation with summer crops like soybeans.

Most of the wheat grown in Georgia is in counties along a line from just south of Augusta, through Perry, Americus and into the southwest corner of the state. To date, Georgia farmers report 84 percent of their wheat is in fair or better condition.

In 1997, Georgia farmers grew 15.8 million bushels of wheat. Its value was a little more than $50 million.

Scientists with the UGA College of Agricultural and Environmental Sciences have found ways to control the insects in Georgia grain fields.

Dewey Lee, a UGA extension small-grains scientist in Tifton, said, "We can successfully treat for these beetles. They're generally a problem at the same time aphids and stinkbugs are, so farmers can scout and treat for all three with a minimal added cost."

Buntin is studying how natural enemies of the beetle can help control the populations and the damage they cause. Although birds usually provide some control, the leaf beetles place their own feces on their backs, and birds don't like the taste.

Researchers in the Great Lakes area have used parasites to infest and decrease cereal leaf beetle populations.

Buntin and other Southeastern scientists are working to learn if the parasites can live in this region and control cereal leaf beetles. If they can, farmers may soon rely on them and decrease their pesticide use.