By Mark VanGessel, Extension Weed Specialist; firstname.lastname@example.org
I always get questions on what to use to control mornningglory in soybeans at about the time to spray postemergence. Morningglory control starts at planting with a preemergence herbicide with broadleaf products such as Canopy, Valor XLT, Envive, Fierce, Prefix, Sonic or the Authority products. These will need to be followed up with a postemergence application in a timely manner for effective control (to morningglory no larger than 3”). The preemergence herbicide slows the growth of morningglory plants and seems to “set them up” for better overall control. This has been more consistent for morningglory control than any tankmixtures or glyphosate additives that I have evaluated.