Doug Johnson, Extension Plant Pathologist, University of Kentucky
I have been getting lots of questions about the bugs shown in this photo. Can you identify them? Folks are seeing lots of them in soybean fields. This photo by Patty Lucas shows a nice assortment of the nymph stage (immature) green stink bugs. It is quite common to aggregates of these near the end of the season. They are generally noticed because they are near the tops of plants, and leaves are beginning to drop.
Figure 1. Immature green stink bugs on soybean.
Notice that unlike their nearly always solid green adults, these nymphs have lots of bright colors. In addition they lack the wings that adults have. Just remember that no matter the color or size all insects with wings are adults, and with the exception of a few primitive or very specialized types, all insects without wings are immature.
These groups always raise concern that lots of damage is occurring. However, for the most part when one starts seeing this, the plants are too mature for them to damage much. Nevertheless, one should take heed that the older relatives of these nymphs have been around for a while. We generally have two complete generations of green stink bug in soybean in Kentucky. Unfortunately, green stink bug is one of our most under-recognized pests, because the adults are green, their early feeding damage is difficult to spot, and are usually down below the very dense canopy that our soybeans produce.
Source : grainblog.uky.edu