Herbicide issues in the Carolina-Virginia region have become more complicated in recent years. This is true generally, but is especially true considering expanding resistance issues. N.C. State University crop scientist Alan York officially retired four years ago but he is still on the job, both in a limited role with the university and also as a consultant for grower associations. He recently talked to growers at an Extension crop meeting in Wayne County, N.C., and noted some new herbicide products on the market that he has been researching and that are helping soybean, corn and cotton growers control weeds in a variety of situations.
Sharpen is a product from BASF, York said, that has a fit in the herbicide programs of many growers. BASF notes, among other uses, Sharpen can be used as an enhanced burndown in soybean (not in CA), in seed corn (not in CA), and under a supplemental label as a preplant surface or residual preemergence to field corn and popcorn.
"Sharpen is extremely good on horseweed," York said. "Not only will it kill what is up but it also has some residual activity, so Sharpen is a good choice. You can put Sharpen on corn on the day you plant. With soybeans it depends on the soil and in Wayne County (the area of his audience) you're looking at 30 days ahead. The catch on cotton is that it has a 42-day waiting period. That is relatively important."
Another product York has experienced good results with is LeadOff by DuPont. This is a product with the active ingredients Rimsulfuron and Thifensulfuron methyl.
"A lot of people used LeadOff last year and will probably be using it again this year," York said. "We look at LeadOff as having its best fit is as an early burndown, even at Christmastime or in early December. Put it on in the fall where you don't have a cover crop. You can use it to get rid of all the junk weeds, henbit and weeds like that. That way when planting time comes your fields are still pretty clean."
LeadOff is applied 30 days prior to planting cotton or soybeans. Corn can be planted immediately after application.
York noted a grower could use LeadOff in late fall and then still choose to put on another burndown and some residual in the spring if he chose to do so. He noted LeadOff has shown some residual activity on horseweed.
"It will keep them from coming up," he said. "Will it kill them after they're up? My experience has been if you (catch them early) it does pretty good. If you don't catch them early, it is going to need some help."
York noted that Fierce from Valent just received a label for corn. It is a two active-ingredient material; one is the same active ingredient that is in Valor, Flumioxazin, and the other is Pyroxasulfone.