Here's a timely report on pest control in hay and pasture crops. Dorage crops harbor more insects than almost any other crop we grow. One of the dangers is that they may build up here and "move out" to other crops.
Lilly, J. H.
"Pest Control in Hay and Pasture Crops,"
Iowa Farm Science: Vol. 10
, Article 2.
Available at: https://lib.dr.iastate.edu/farmscience/vol10/iss12/2