Farm & Home
Ag Line: Insecticide Management for Hessian Fly and Aphids
By Wade Parker
County Extension Coordinator

Wheat prices have nearly doubled since the start of the year. Some officials have said crop worries and strong global demand will keep prices firm until a clearer picture about U.S. plantings emerge in January. As everyone is well aware, it will take high prices to offset the dramatic increase in production expenses. The cost of fuel and fertilizer is rising just as fast as wheat prices. As with any other crop, a producer cannot benefit from high prices until the crop has been successfully harvested from the field.

This year we have many different varieties planted. I had calls from folks asking about varieties that were planted in the mid-90s. No variety should be immediately discounted, but just make sure you are aware of the different characteristics that makeup the hybrid. I feel that planting is near completion and this is probably not much of an issue.

Hessian fly management in wheat begins with variety selection. While we have not experienced pressure from the Hessian fly, every year is different. If you have a variety that is rated good or fair by UGA standards for Hessian fly resistance- i.e. AGS 2000, Pioneer 26R61, AGS 2010- then chances are you will not experience a problem. However, some varieties are not as strong on Hessian fly resistance such as USG 3209, McIntosh, Panola, Coker 9553, and Pioneer 26R24.

What can we do now to protect wheat?

An application of a long-residual pyrethroid insecticide (Karate/Warrior and similar products) can suppress Hessian fly infestations if it is applied while adults are laying eggs, eggs are present on leaves, and before larvae become established in the stems. Studies in North Carolina have found that a timely application at 2-3 leaf stage after emergence can significantly reduce fall infestations. However, studies in Georgia have found Warrior applied at 2-4 leaf stage is variable in efficacy. Nevertheless, this approach may be suitable for susceptible wheat varieties under intensive wheat management that includes routine scouting for insects. Leaves should be sampled for Hessian fly eggs while sampling for aphids. The approach is most appropriate for fields planted with a susceptible variety that has not been treated with a systemic seed treatment AND when wheat is planted early, wheat is planted in the same field or within a few hundred yards of previous year's wheat fields, and/or Hessian fly has caused losses on the farm or adjacent farm in previous years. Fortunately, we have not experienced any problems in recent memory.

The treatment above does have some variability involved. In other words, if you can apply it while the adults are laying eggs, it will work wonderful. If wheat acres continue to increase in the next few years, we will definitely have to tighten our belt with fly management.

I hope everyone has a safe and fun Christmas season!

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