Do you know what this critter is?  The lesser cornstalk borer is an uncommon pest of late planted soybean, corn and peanuts.  I’ve had a couple of complaints about this pest on soybeans from the Mississippi River Bottoms, and I have also observed dead plants first hand.  When lesser cornstalk borer causes a problem, it is almost always in late planted fields grown on sandy soils.  The larvae make silky tubes in the soil around the base of plants and tunnel into the main stem.  This will stunt or outright kill the plants. The injury could easily be confused with pythophthora root and stem rot.  Look for silky remnants and tunneling around the base of dead or dying plants.  The larva is fairly distinct, with rows of pinkish to purplish bands around the body.  Similar to green cloverworm, it will often wriggle violently when poked and prodded.  Unfortunately, there are no effective insecticide options.  The pictures below are courtesy of Jason Hamlin.