Too little, too late. Too many insect control programs in legume seed fields have been carried out that way. Don't let the second crop go until bloom time without attention to harmful insects or preparing for pollination. It's too late then to make a "shot in the dark" at successful legume seed production.
Lilly, J. H. and Haws, B. A.
"Protect Your Legume Seed Crop,"
Iowa Farm Science: Vol. 5
, Article 5.
Available at: https://lib.dr.iastate.edu/farmscience/vol5/iss1/5