There have been a number of folks enquiring how to control fescue, bermuda grass, broomsedge, switchgrass and other warm season grasses in corn. My first thought when I get one of these calls is that weed control is more than likely the least of the problems if one has planted corn into set aside or old pasture land. For example if broom sedge is a real problem in a corn field soil pH and probably fertility are likely very low. Please refer to Dr. McClure’s article on raising crops in set aside or old pasture land for recommendations. Getting back to weed control, fescue is relatively easy to control in corn as atrazine will very effectively control it. The warm season grasses like broomsedge and bermuda grass are another issue. There are no real good options for warm season grasses in conventional corn. Herbicides like Accent, Option, Callisto or Laudis will hardly check up the growth of warm season grasses like bermuda grass. The only real option is to plant a Roundup Ready corn hybrid and be prepared to spray at least twice with glyphosate. It is the only effective option for warm season grass species.
what should a man apply over the top of his corn if he applied r/up plus bicept pre plant, has had trouble w/ the grasses mentioned above. will have to put another shot of r/up. wants to use halex but is a second shot of dual ok or would it be best to use another mode of action. what would u suggest?
Jonathan
That is a good question. Unfortunately, we do not have many good options. It will take another shot of glyphosate at the very least. Hales GT has glyphosate in it so that works fine. The dual in it can help as well on any new emergence from seed. With all the wet weather it may have to be sprayed again. One other option on Herculex corn hybrids is an application of Ignite. If there is a 3rd regrowth Ignite would probably be a good fit here.
Larry