Based on some phone calls, grasshoppers are causing some serious injury to seedling soybean in some localized areas.  This is not uncommon, especially in reduced tillage fields and also tends to be worse following a previously dry year.  Treatment should be made if stands are being threatened or anytime defoliation levels exceed 30-40%.  In seedling soybean, it is almost always high populations of immatures that are causing the problem.

The best treatment for immature grasshoppers is Dimilin 2L at 2 oz/acre.  This treatment does not control adults but is very effective on immatures and provides good residual control and rainfastness.  My second choices would be Orthene/Acephate at 0.5 lb active ingredient per acre (= 0.56 lb of the 90S formulation).  Synthetic pyrethroids are an option but not my preferred treatment.