People tightening their belts have discovered non-GMO hybrids are considerably less expensive. How do you control insects without GMO traits?
It may seem like a ‘Land Before Time’ question if you’ve become accustomed to letting genetics take care of insects. Two members of this month’s panel of Indiana Certified Crop Advisers note there are still alternative ways to control pests. Panel members include Steve Gauck, regional agronomist for Beck’s Hybrids in southern Indiana; Tom Stein, manager at Templeton and Boswell Ceres Solutions outlets; and David Taylor, agronomist for Harvest Land in east central Indiana.
Question: We’re going back to all conventional hybrids to save on seed costs. We were controlling insects with traits. What adjustments should we make in our insect control program?
Taylor: To develop a new insect control plan, the traited system must be understood. What insects were controlled and when during the growing season? The Handy Bt Traits Table is the most complete reference for traited corn. Compare insect issues you may have on your farm and insects that you were able to control in the past with traits. Find it at: msuent.com/assets/pdf/28BtTraitTable2014.pdf.
If corn rootworm has been a problem, soil-applied insecticides should be considered. Several are available. Some have greater efficacy on rootworm larvae than others, meaning some are more effective. Do your homework prior to selecting a product.
Stein: I’m going to pass on giving specific recommendations for insect control in conventional corn. I believe I can make a case for staying with hybrids with traits despite the extra cost.
Gauck: Below-ground (GMO) traits only control rootworm. Using a soil-applied insecticide at high rates in a moderate rootworm pressure area should take care of them. If you’re in a high pressure area, use a granular insecticide.
Taylor: Another early-season insect controlled by some events is black cutworm. If traits were the control measure before, insecticides are now your best bet, either with soil insecticides being applied- some are good on cutworm- or by scouting and spraying if cutworm populations become yield-limiting.
Gauck: Above-ground insects can be more of a challenge. This requires knowing what insects you’re targeting- corn borer, ear worm, army worm or cutworm. This takes scouting your fields throughout the year.
We must identify insects before they enter the plant. Timing is critical to get good control. Watching the Purdue University Pest & Crop Newsletter helps get a good idea of when moth flights of these insects are high. That lets you time scouting passes.
Taylor: Another major pest is European corn borer. Of rootworms, cutworms and corn borers, corn borer is the most difficult to control. Across Indiana corn borer generally has two generations or hatch periods. The second generation hatch is usually most damaging, causing ear drop and weakened stalks. Control outside Bt traits is difficult, with timing being critical.