Producers and consultants, keep your eyes open. Some early-season pests are showing up in Arkansas and Mississippi fields in worrisome numbers.
“False chinch bugs are all over some no-till fields where burndown went out a little late,” says Gus Lorenz, Arkansas Extension entomologist. “In some cases, we've seen some extremely high numbers.”
Lorenz was recently in a field where the pest was numbering 200 to 300 per square foot. “They were as thick as I've ever seen them. They were jumping all over some soybeans. The producer had burned down late and planted right behind. As the weeds began to die, the false chinch bugs were moving into the seedling beans. They can kill the plants; it was a bad situation.”
An abundance of chinch bugs is also evident. “They're about as bad as they've ever been in corn and milo. They're all over the state.”
There have been “many” treatments for chinch bugs already. Much of the corn that didn't receive an insecticide treatment — seed or in-furrow — is “being hammered.”
In Mississippi, “we've been busier early than we have in a few years,” says Angus Catchot, Mississippi Extension entomologist.
Mississippi's hill area is playing host to high numbers of bean leaf beetles. “We always have them, but we're seeing some unusual numbers. Some fields, even with a threshold between 35 and 40 percent seedlings defoliated, have been treated.”
Mississippi corn has had “quite a few” stink bug problems. Those have been across the state, although mainly in the Delta region. Most of the corn is now moving out of the stage when it's very susceptible to stink bugs.
“Chinch bugs have also been trouble in our corn and have been treated,” says Catchot. “But with the recent rains, things are looking up. The nitrogen under the corn is melting in and the crop is beginning to grow off well.”
Catchot has found some false chinch bugs. “But they aren't at the levels Arkansas is seeing. I don't know of any Mississippi fields that have been treated.”
Several calls about cutworm have also come in. The cutworms are being found in corn and young cotton. Most producers are banding a pyrethroid behind the planter and burning down early. But even in some of those situations, “we've had to treat in a few spots.”
Prefacing his comments with a desire not to alarm anyone, Catchot says spider mites are being found in cotton. “It isn't anything to be terribly concerned about yet. Generally, we have this pest in cotton every year. I only bring this up because when seed treatments begin wearing off and producers start making thrips applications, they need to be careful of what is sprayed. We don't want to flare the mites and make the situation worse.”
Lorenz has also taken calls on spider mites in southeast and eastern Arkansas cotton. “That isn't a good sign. We're hoping all the recent rainfall will help us with those and knock them back.”
Louisiana has escaped many of its neighbors' pest problems. “Pests have been light so far, and we've been getting a lot of rain,” says Ralph Bagwell, LSU AgCenter entomologist. “The rain probably alleviated many of the early-season insects that normally cause us problems. Rains can knock them off and decimate a lot of seedling pest populations.
“There are fields being sprayed but there aren't the pest densities we've seen in recent years. I count us fortunate compared to some of the other (Mid-South) states. Hopefully, that will continue because our farmers don't need to spend any more money than is necessary.”
Lorenz says producers in the southern half of Arkansas are also dealing with “vegetable weevils cutting cotton plants. Those cause injury similar to cutworms. They'll cut just below the cotyledons.”
Bean leaf beetle feeding has been moderate to heavy across the Arkansas Delta. “You can tell where the producers used an insecticide seed treatment. There's a marked difference where there's some control with these new seed treatments like Cruiser and Gaucho.”
As far as root-worm pests, grape colaspis is showing up in Arkansas' seedling rice. Lorenz expects that situation to get worse as the season progresses.
Meanwhile, some of the state's wheat crop has had stink bugs in abundance. “Although we don't normally worry about those in wheat, the numbers were extremely high in some locations. Our threshold is one stink bug per 10 heads. Even so, fields were treated so that should indicate how thick they were. Treated fields were concentrated in the south half of the state, but we got stink bug calls from the northeast to the southeast.”
Wheat serves as a nursery for stink bugs. “With the populations we've already seen, that's a heads-up there could be problems when the rice begins heading.”
Thrips are just now finding Arkansas' seedling cotton — even cotton with a seed treatment. Immature thrips are being found, indicating the pest is reproducing in the fields.
Thrips are especially plentiful in mid-April planted cotton fields in the Phillips County/Lee County area.
“From my perspective, the potential for a heavy pest year is obvious,” said Lorenz. “We've got to watch things closely. It seems the sucking bug complex (chinch bugs, stink bugs, false chinch bugs) is out there in higher numbers than usual.”
A further disturbing find: when weed hosts (henbit, cutleaf evening primrose and others) were recently checked for tarnished plant bugs, high numbers of the pest were found. “That doesn't bode well for our cotton crop. Based on what we've seen, I think it's safe to predict we'll have at least a fairly significant tarnished plant bug year. That's what we're telling everyone.
“Producers and consultants should keep alert. A lot of things can happen and it's tough to make a watertight prediction. But it's shaping up to be a busy year for insects. The mild winter we had is hurting us. There wasn't much winter pest mortality and we're paying the price now.”
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