FALL ARMYWORM INFESTATION BLANKETS STATE
July 31, 2014
An example of Lamar County farmer Will Gilmer's sorghum patch. “I have never seen that many at one time or that much of a variance in size,” Gilmer said. “Two years ago we lost 15-20 acres of soybeans, but this year we caught them early.”
Farmers are feeling the affects of the second wave of fall armyworm attacks as they munch into crops across the state.
Lamar County farmer Will Gilmer said he lost 10 acres of sorghum, but it could have been worse.
“I have never seen that many at one time or that much of a variance in size,” Gilmer said. “Two years ago we lost 15-20 acres of soybeans, but this year we caught them early.”
Kathy Flanders, entomology and plant pathology professor with Alabama Cooperative Extension System (ACES), said the worms live in Florida, Mexico and Texas during the winter, and the moths migrate as it gets warmer. The number of moths migrating north determines the amount of damage.
“It’s not the worst year, but it’s shaping up to be moderately bad,” Flanders said. “Armyworms reproduce up to six generations in a year, and each generation creeps farther north, reaching New York by fall; hence the name.”
Flanders said infestation reports usually come in mid-July, but this year reports came the first week of July.
“Moths will come up underneath tree limbs or lay eggs right in the ground,” Flanders said. “Caterpillars hatch, then feed for two and a half weeks. After they finish feeding they’ll go into the soil and pupate to become a moth, and it starts all over again.”
Flanders said sweep nets, available at county Extension offices, can help farmers detect worms. To stay updated on infestation reports in each county visit alabamaforages.com, which contains an interactive map regularly updated by ACES.
“We’re tickled about the program, having farmers out there using sweep nets trying to find fall armyworms,” Flanders said. “The key is to find them before they’re too big. They do 80 percent of their feeding in the last four days of their lives. That’s what our sweep net program is all about.”
Former row cropper and Bermuda grass producer Frank Talbot said the insects have wormed their way into the Wiregrass, too.
“We’ve had a pretty good outbreak of them down here,” Talbot, a Pike County resident, said. “We got an inch of rain last Friday night, and that helped a bit. They do not like rain. They like it hot and dry. I’ve talked to quite a few growers the last several days, and they’re spraying to control the problem.”
Flanders said farmers should spray when worms range from two to three per square foot, but if they’re close to cutting and see damage, to cut anyway.
“If you go on the forages webpage and click on the watch map, there’s a button that says ‘Click here for more information,’ and there’s a spray formula.”
To report armyworm infestation contact Flanders at firstname.lastname@example.org, or contact your local animal science agent.
For more information on armyworms click here.