Insects prompt concern for crops

Above-average outbreaks feared

Early signs of crop-killing insects have been found around Arkansas, and rice and soybean farmers will need to take action to keep the pesky bugs from affecting crop yields, according to university researchers.

Gus Lorenz, University of Arkansas extension entomologist, has worked in his field of expertise for more than 30 years, traveling the state as a consultant for farmers. This year, he said, he has seen bug outbreaks a month ahead of schedule.

“We’re expecting insect pressure to be above average; how bad it will be is anybody’s guess,” Lorez said.

The mild winter this season played a role in low insect mortality numbers, which have spawned early insect swarms on rice and soybean farms.

Grape Colaspis and its larvae, known to farmers as lespedeza worms, burrow into the ground and in warmer months influence rice yields. The females lay eggs in late October and when they hatch, the grubs travel into the soil. In the warmer months of spring, the crops sprout and the larvae start feeding on the roots, which can cause seri-

ous rice damage, Lorenz said.

“This past season it was so mild that the over-winter mortality wasn’t as high as it would normally be,” he said. “It was good for those insects and as a result of that we’ve had a lot of insects that were able to survive over the winter.”

Other bug sightings around Arkansas include the redbanded stink bug and armyworms.

Primarily found in Louisiana, the red-banded stink bug has migrated farther north into the southern and central Arkansas Delta regions.

“They aren’t like our traditional native stink bugs,” Lorenz said. “They cause a lot more damage and they’re harder to kill.”

On average, if red-banded

stink bugs are not controlled properly, farmers could see as much as 25 to 40 percent yield loss on soybean crops, he said.

Also, fall armyworms have been spotted a month ahead of schedule in Arkansas, largely because of the warm winter months. Normally, cold weather would kill armyworms down to the Gulf Coast, but this season they weren’t pushed back as far south, said Jarrod Hardke, rice extension agronomist for the UA System Division of Agriculture.

“They’ll hang around as long as conditions are good,” he said.

Stink bugs that are native to Arkansas show signs of activity around late July at rice farms, but Hardke has seen large populations of them near roadside ditches in late April, nearly three months ahead of schedule.

To prevent crop damage, Hardke recommended farm-

ers manage non-field areas where there can be an alternate host for bugs away from crops.

Similar weather activity in the past has proved more beneficial to farmers, in spite of the early bug warnings, but the usual outcome is more costly.

“Unfortunately that’s the more common refrain,” Hardke said. “You do have populations where it’s a serious cost for growers to manage and [bugs] just keep coming into the field.”