Mark VanGessel, Extension Weed Specialist; mjv@udel.edu
I have visited a number of fields and took phone calls about Italian/annual ryegrass control in corn. In many cases, the ryegrass is the only plant that survived the burndown treatment. Ryegrass is hard to control ahead of corn. Glyphosate is the standard treatment, but it should be applied by itself, with water, and applied during a string of days with 60+ temperature. When going into soybeans, Select/clethodim or similar product in combination with glyphosate is the best option.
Most of the fields have only few scattered plants and it was not necessary to retreat. Those corn fields with high densities should be retreated with glyphosate plus Resolve/rimsulfuron.