In recent weeks, I have inspected several soybean fields with palmer amaranth infestations.  Palmer amaranth is a noxious weed in Ohio, http://codes.ohio.gov/oac/901:5-37-01 and capable of wrecking havoc with soybean production if allowed to spread.  At this point in the season, there is no rescue treatment for palmer amaranth.  If hand pulling and weed removal is not feasible, the best course of action may be to destroy the field by mowing and then tillage or by mowing followed by an application of paraquat.  More information and identification photos are available at https://wayne.osu.edu/palmer-amaranth-photos.