By widening corn rows and taking certain precautions, it's possible to establish interplantings without a great loss in corn yields. Some problems remain to be overcome, but the future of this practice looks bright.
Schaller, F. W.
"Forage Crops in Corn?,"
Iowa Farm Science: Vol. 7
, Article 4.
Available at: https://lib.dr.iastate.edu/farmscience/vol7/iss10/4