Some questions have recently come in regarding herbicide options for corn in later vegetative stages. While early-season weed control is critical to protecting yield potential, in some situations, late-season weed control may be needed to protect yield, prevent harvest difficulties, and reduce additions to the weed seed bank.
Corn over 12 inches tall still has herbicide options, but fewer than earlier growth stages, and some require special precautions. This article summarizes what is allowed, when to apply, and how to reduce crop injury. Get the table of labeled products and height limits here.