Ferrie: 5 Ways to Stop Early-Season Pests and Insects Now
In this week's Boots In The Field podcast, Farm Journal Field Agronomist Ken Ferrie addresses agronomic problems -- insects, diseases and rodents -- he’s anticipating now and how you stop them in their tracks – before they can contribute to lost yield. Here are five recommendations Ferrie encourages farmers to implement now.
1. Place Cutworm And Armyworm Lures
Cutworm and armyworm moths are leaving southern climes now and heading north. They are attracted to any type of green foliage in fields this time of year where they can move in and lay their eggs. If they don't find anything green in the field, Ferrie says they will look for any suitable vegetation.
“For sure the wheat acres need to be addressed for armyworm, and corn going into cover crop fields needs to be addressed for cutworm,” he says. “No-till fields without a winter burndown get green with winter annual weeds and carry a risk as well.”
Ferrie says a green field can be inundated by the moths, while a tilled field next to it might not contain any moths. He adds that once eggs are laid, tilling the field will not stop cutworm development.
The good news is a little time invested in trapping the moths will take a lot of guesswork out of which fields are at the highest risk.
“Many of you guys who are going naked on fields of first-year corn – not using an insecticide or a seed treatment – will be making it weak on cutworms,” he says. “Cutworms aren't too hard to control with a rescue treatment, if the pest team stays on top of it and you pull the trigger quick enough.”
Ferrie says corn growers who are new to using cover crops often get caught off-guard by cutworm infestations. He encourages them to consider these three control options now:
1. Be preemptive and put a cutworm program in place in those fields.
2. Put traps out, watch the pheromone trap numbers and then make a call on whether to treat based on the pest numbers you see in each field or each location.
3. The third option is to scout the fields you're going green into when the corn emerges. Be in those fields on a daily basis, checking the pest numbers and then pulling the trigger quickly to stop any losses.
“Cutwarm is not one to scout from the coffee shop consensus program, especially if the coffee crowd is not planting covers,” Ferrie says.
“We need your help to keep tabs on both of these two pests,” Ferrie adds. “Like in the past, if you guys (in Illinois) would check the traps and call in your counts, we'll supply the lures for you. I know some of you have pheromone traps from last year and you only need the lures. We also have wing traps for anyone who wants to help but doesn't have a permanent trap.”
2. Ready Wireworm and Grub Bait Stations
Setting up a bait station is a simple process. Here are the steps:
1. Dig up 1 cubic foot of soil—a plot of dirt that’s 2’ long, 1’ wide and 6” deep.
2. Throw a handful of untreated corn seed and a handful of either untreated wheat or untreated oats in the bottom the hole.
3. Place the dirt back over the hole, then cover it with some black plastic to enhance the sun’s warming process.
4. Wait two weeks, then check the trap and see if you find any pests in it.
“If you find one wireworm or two grubs in that grain mixture you threw at the bottom of the hole, you're going to need to apply an insecticide,” Ferrie says.
He adds that wireworm numbers have been on the rise for the past five to seven years in central Illinois and other parts of the Corn Belt.
“If you have had to replant corn in fields or parts of fields the last couple of years due to wireworms or grubs, don't bother with the bait station. Just put insecticide on that field,” he advises. “If you're using a seed treatment, go to the higher end of that seed-treatment rate.”
3. Avoid Stewart’s Wilt By Addressing Flea Beetle
Above-average temperatures for the past three months could contribute to flea beetle issues this season.
It’s a problem many farmers have not experienced recently, and Ferrie is concerned there’s a significant risk for the pest this year. While the flea beetle puts stress on corn plants, that’s not Ferrie’s primary concern.
“The real problem is the flea beetle is the vector for Stewart's wilt,” Ferrie says. “You may want to check how good the Stewart's wilt score is for each hybrid you plant.”
4. Gophers Can Ruin a Field's Ability To Grow Crops
The thirteen-lined ground squirrel is emerging from hibernation. The male shows up first; about a week or so later the female shows up with mating season commencing. Mating season lasts about two weeks. Now is the time to address this pest, before it reproduces as each mating will result in three to 14 offspring.
“If we can get their numbers knocked down during mating season, your success of keeping the population under control goes way up,” Ferrie says. “Squirrel colonies will just continue to grow if you don't stop them, and the problem will get bigger each year.”
Because the thirteen-lined ground squirrel reuses tunnels year after year, you can use aerial images from fields and scouting reports to know where to place the bait stations.
5. Get Vole Numbers Under Control
The vole has a gestation period of only 16 to 24 days, delivering three to six offspring per litter, which mature quickly and continue repopulating.
“Each female vole has five to 10 litters a year. That’ how one becomes 50 in a hurry,” Ferrie says. “Voles are like rats in a granary when it comes to multiplying.”
Predators such as coyotes and hawks provide the best control of voles. However, predators can have a difficult time catching voles in no-till fields with a lot of residue and, even more so, in fields planted to cover crops.
Ferrie says bait stations can help take out voles, and he has heard that bait plows do a good job, though he has not used them.
“In the no-till fields when the pressure gets bad, one pass with a vertical harrow helps a lot to expose voles to predators. In cover crop fields if they get bad enough, you'll have to take them out of covers until you get the voles under control,” he says.
Read more from the Unspoken Truths About Pests series
Ferrie: Seize Your Corn Growing Opportunities for #Plant2023
Ready, Set, Go! Plan Now For The Perfect Planting Season
Ferrie: Nitrogen-Friendly Growing Season Results in Corn Yield Bonanza
