AUBURN UNIVERSITY, Ala.—There are many risk factors associated with production agriculture—many of them including aspects that producers cannot control. Weather, rainfall and pressures from cotton pests are all factors with a large impact on plant growth and maturity.
Scott Graham, an Alabama Extension entomologist with a focus on cotton, soybeans and peanuts, said it is important to develop a plan early in the season to help mitigate those risks.
Early Season Cotton Pests
“Thrips are an obvious early-season pest,” Graham said. “They are really the most consistent insect pest in cotton—maybe even in row crops in general. When you look across the Cotton Belt, probably 100 percent of our cotton acreage has thrips infestations.”
Neonicotinoid insecticide seed treatments are the industry go to. There are other available options for foliar supplemental insecticide applications growers can apply as needed.
“Generally, thrips injury is a function of how well your cotton crop is growing,” he said. “So earlier in the planting window when nighttime temperatures are a little bit cooler, heavy thrips injury is more likely.”
Later in the planting window, the cotton will grow faster and the pressure from thrips will be less. Graham said nighttime temperatures are important. When it is cooler at night and the crops are only growing at night, the thrips are really able to feed and do heavy damage.
Grasshoppers are also a pest to look out for. Graham said immature grasshoppers are truly a risk pest.
“Some years they’ll be in fields, but won’t touch a cotton plant,” Graham said. “Other years, they’ll turn on the cotton and eat 10 to 15 acres in a short time period. We never really know what grasshoppers are going to do until they’ve done it.”
Graham said it is really important to control immature grasshoppers while the cotton is still coming up in the crook stage, because producers need to establish a healthy stand. He said producers shouldn’t worry about defoliation.The more pressing issue is preventing grasshoppers from clipping off plants and hurting the stand.
Critters: Snails and Slugs
Although snails and slugs do not fall into the insect classification, the critters are still an issue for crop producers.
There are many questions surrounding snail damage in the field.
“Snails are a problem that started in the southern part of the state but have made their way north” Graham said. “Fields in Cherokee County had to be replanted from snail damage in 2020. Unfortunately, there is not a lot producers can do to get rid of snails and slugs. There are some marginally effective baits available, but the baits are expensive.”
Graham said light tillage would be a control option. Slugs in particular are an issue following a grass crop—like corn and sorghum. Pushing the residue off of the furrow and making sure the furrow completely closes are both options to help mitigate slug issues.
Alabama Crops Report Podcast
For more detailed information on control for thrips and other early season cotton pests, check out episode eight of the Alabama Crops Report Podcast. Find information on neonicotinoid seed treatments, snail and slug control, as well as timing for foliar insecticide applications.