David Owens, Extension Entomologist, owensd@udel.edu
Soybean
Check any double crop field that was treated for corn earworm for soybean looper. Large populations were observed this week in southern Sussex. Soybean can handle more defoliation in the R6 stage, but if we go above the 20-30% range, treating may still be justified. The loopers observed were small, and defoliation was very low. I suspect that loopers are not going to be happy this week with cool weather and natural enemy activity, but keep an eye on them. Some isolated spots of corn earworm are reappearing in soybean, mostly early instars. R6 beans are still susceptible to CEW damage. Wait and see if the worms develop though. Mortality is going to be fairly high in the early instars and may be high enough to not require a treatment.
While looking for loopers and earworm, check for stink bugs. Once soybeans reach the R7 stage, treatment for stink bug is not necessary.