We have been expecting some pest troubles to develop in our later crops in Hale & Swisher counties for some time. Last week we found several sorghum fields (most just entering soft dough stage) with economic bollworms, one of the species that commonly make up the sorghum headworm complex. Unfortunately, we are finding that the bollworms are not alone.
This week we are finding several FAW (fall army worms) following the bollworms into the sorghum fields, just a touch behind. The ET (economic threshold) for any sorghum headworm is roughly the same without much regard to larva species. Literature regarding headworm control, etc. can be found in Managing Insect and Mite Pests of Texas Sorghum. However, species identification is crucial if your field does have an economic headworm problem. Most of the labeled products for bollworm (i.e. corn earworm) will not control FAW larva. In this case, we must change our recommended treatment to a product that has a chance to control both. Changing products does come with a higher sticker price, so we really need to make certain of your species present before applying any labeled product for headworms. Good photos to aid with larva identification between bollworm and FAW can be found in the July 5 edition of FOCUS.
Of course sorghum is not the only area crop the FAW will attack. Corn, cotton, early planted wheat, and even several hay crops are at risk. I am finding several FAW in late planted corn, and a small number in cotton, but at this time they seem to prefer the later planted sorghum that is just moving toward soft dough stage.
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