Dry spell means pest problems for farmers

Already stressed by heat and dry weather, row crops in northwest Missouri are under increasingly heavy attack this summer by insects, and area ag consultants are urging producers to be on the lookout for both the usual suspects and several drought-loving newcomers.

"This year we have lots of pests that aren’t usually seen in this part of the world," said Wayne Bailey, a University of Missouri Extension entomologist.

A leafhopper, normally found in Texas, has gone after Missouri wheat, and the redheaded flea beetle is showing up on corn.

"They're clipping silks on corn this year," Bailey said. "That’s something I haven’t seen in my 28 years with the university."

More typical Missouri pests are out there too. Japanese beetle numbers are high in some areas and go after both corn and soybeans. Spider mite numbers could explode because they love dry weather, which Missouri certainly has an abundance of this year.

"What you’ll see is an off-color in the field, often in spots along the edges," Bailey said. "In dry, dusty conditions their populations can double every seven to ten days."

Holt County Extension agronomist Wayne Flanary said Thursday there have been reports of spider mite infestations near Cameron and in southeastern Nebraska. He has received no such reports for Nodaway County, though that could soon change given the weather forecast.

"They just love this type of dry weather," Flanary said," adding that some farmers may have a spider mite problem and not yet know it. Due to drought, soybeans plants are smaller than usual, making it easier for the pest to be overlooked.

Bailey suggested that farmers take a piece of white paper into their fields, place the paper under a leaf and tap the leaf-top. If light brown, tan, yellowish or red dots start crawling across the paper, they're likely spider mites.

"If you have them, you need to do something pretty quick," Bailey said.

Producers whose soybeans are flowering should also look for signs of infestation by the spotted cucumber beetle or southern corn rootworm beetle. They’re the same insect, just two different names.

"It’s a yellow beetle with black spots, and it’s feeding on soybean flowers," Bailey said. "We’re seeing many more of them in soybean fields where they are either defoliating or going after flowers or both."

Another problem is the striped blister beetle, whose numbers tend to rise and fall with grasshopper populations. This pest is found on both soybeans and alfalfa, but it’s an especially severe problem in alfalfa.

And as usual during a drought, grasshoppers are thriving.

"We are seeing grasshopper damage," Flanary said. "They're looking for anything green that they can feed on."

Of course, increased pest activity is just one of the challenges associated with northwest Missouri's deepening drought. With sufficient rainfall, it's still not too late for many row crops to recover, Flanary said, but the outlook is not bright.

"It's getting worse by the day," he said, adding that the current heat wave with temperatures over 100 degrees has come at "a critical time" for corn, which is entering the all-important pollination period.

Cooler weather is expected by early next week and could lower plant stress. But what farmers need is rain.

As for soybeans, Flanary said they are "starting to take off," though stunted by dry weather and "not growing as rapidly as we would like."

"It's not looking good," he said with regard to the overall crop outlook. "We haven't had a really bad dry situation in quite a few years, so we'll just have to wait and see how this all plays out."