Winter wheat planting is underway in the Carolinas, in many fields behind soybeans. Randy Weisz, NC State Extension Small Grain Specialist says that the Hessian fly continues to be a menace to early planted wheat fields:
"Any time you harvest wheat, there are usually some hessian fly in the field at harvest time. Usually there are so few that we don't even think about them. But by the time harvest roles around, they have pupated and the pupae are in the wheat stems. In the old days, we tilled before we planted beans and that killed the flies. But now that we no-till, almost all of our double crop beans, the flies are left in the soybean field."
The destructive Hessian fly problem appears most commonly in fields where wheat and soybeans are in constant rotation, according to Weisz:
"If he's planting before there's a good freeze to kill the flies, then the flies will infect his wheat crop almost as soon as it comes out of the ground. So, most of the cases where we've seen hessian fly problems, not all of them but most of them, have been where growers have been planting continuous wheat-beans-wheat-beans and the flies are there in the old residues."
While seed selection has already been made, purchased and is stored in the barn waiting to be planted, Weisz says the best defense against the fly is resistant seed varieties. With that being said, all is not lost; there’s a couple post-plant options:
"Use an insecticidal seed treatment and that is usually very effective. And the third thing that some growers do is they will apply a pyrethroid insecticide, just as soon as the wheat gets two or three leaves on it."
Ideally, winter wheat sould be in the ground by the end of the first week of November, but what with weather conditions and the late soybean harvest, Weisz says that’s unlikely. But, still the sooner the better:
"Well, I think that the main concern that I have is that we certainly are looking at some cool weather coming up here. And, where usually, used to be able to count on the weather turning cold and wet somewhere around the first few days of November and once that happens it gets harder and harder to get your wheat in the ground. And, so my main advice right now is the sooner growers can get the wheat in the ground the better."
North Carolina is expected to plant upwards of 800,000 acres of winter wheat in the 2011-12 season.
Dr. Randy Weisz, Extension Small Grain Specialist