Practically every September some growers are dismayed at the vine infestations present at corn harvest. Often, these weed infestations emerged after PRE applied or early POST applied herbicides had played out. They grew very little until August and as the corn dried down and light became more available those established weeds started rapidly growing.
The vines in question are often perennial in growth habit like honeyvine milkweed, redvine, hedge bindweed and burcucumber. There is really no in-crop option that will provide good perennial vine control. The best one can achieve with an in-crop application is enough vine suppression to minimize harvest issues.
Perennial vines are best controlled with herbicide applications after harvest. The most consistent tactic is to allow the vines to grow back for a week or so after harvest and then apply dicamba and/or 2,4-D. Tank mixing in glyphosate can also increase vine control. For best results go with rates at the higher end of the labels.
Another benefit to managing vines with a PGR herbicide is they will also control horseweed and eveningprimrose.
Finally, perennial vines do not get well established in fields in just a few years but rather over a period of many years. Likewise, complete control cannot be expected in a single year but often requires persistent fall treatments over several years to finally remove them from the field.