Arkansas Farmers Warned About Worms in Beans, Cotton

The moths are here, so the worms won’t be far behind, Arkansas cotton and soybean farmers are being warned.

“A major-league moth flight is coming from corn fields and moving into cotton, soybeans and irrigated grain sorghum fields,” said Gus Lorenz, extension entomologist with the University of Arkansas Division of Agriculture.

The moths lay eggs that hatch into caterpillars that, if they survive, will spin cocoons and emerge as adult moths.

But in their caterpillar form they’re known to farmers simply as worms of various names, depending on the crops they’re eating. And they’re known as a destructive pest that can do major damage to those crops.

In corn, they’re called corn earworms; in cotton, they’re bollworms; in soybeans they’re known as soybean podworms; and in tomatoes, farmers and gardeners call them tomato fruitworms.

“It’s all the same critter, and because it jumps from crop to crop, that’s why it’s the No. 1 pest of Arkansas row crops,” Lorenz said.

Lorenz said the eggs laid by the adult moths hatch after just three days, and then the larvae begin eating the crops.

Lorenz recommended that farmers check fields closely and treat their crops with insecticides when worms reach certain population levels. In Bollgard cotton, that level is two to three bollworms per 14 row-feet, and in soybeans, nine per 25 sweeps with a net.

According to Lorenz, the high numbers of moths showed up recently in cotton.

“We’re finding up to 500 per trap on a three-day catch,” he said.

Fortunately, he said, there’s a lot of cotton still not blooming.

“That’s good because, if any eggs are laid on non-blooming Bollgard or Bollgard II, the larvae that develop won’t fare well,” he said. “If the cotton is blooming, growers need to be watching closely for developing populations of bollworms.”

Likewise, if beans are blooming and setting pods in fields where the moths show up, those fields need to be watched closely, he advised.