The recently registered fumigant, Paladin, offers growers another option to help control soilborne pests.
Like nearly all soil fumigants, the product, which contains the active ingredient dimethyl disulfide, carries a host of Environmental Protection Agency requirements that must be met before and during application.
Among those are applicator stewardship training, a fumigant management plan and buffers.
But Paladin also has what the registrant, Arkema Inc., describes as a distinct garlic-like odor that continues to be an issue with some.
About two years ago, Stanley Culpepper, a University of Georgia weed scientist; Perry Fuller, manager of the TriEst Ag Group Inc., in Tifton, Ga.; and another colleague began exploring soil fumigant blends.
The goal was to reduce the overall amount of fumigant applied and the accompanying buffers yet maintain efficacy, Culpepper says. By reducing application rates, the three figured they should be able to reduce Paladin odor issues and improve economics.
The result was a blend of Paladin, 1,3-dichloropropene and chloropicrin nicknamed WSP. It is used in conjunction with high-barrier mulches, such as virtually impermeable film (VIF) or totally impermeable film (TIF).
“With WSP, you get the best of every world,” Culpepper says.
About 900 acres of WSP went out last year, mainly in Georgia, Fuller says.
“Overall, we’ve had good success with it in Georgia,” he says. “Most everyone repeated.”
Although Culpepper says they planned to tweak the ratio slightly this year to improve it, he said before the start of the season, “As of right now, I’m very excited about it. It’s very effective against nutsedge.
“We’re still trying to find out the best blend. We thought we had the best bend. But on 900 acres, we saw two or three hiccups.”
WSP also has to be used in conjunction with an herbicide program applied over the bed top since it’s weak on many other weeds.
As an agricultural chemical dealer in Georgia, TriEst is legally able to blend products together.
But Fuller says the firm is seeking to trade mark a formal name for the blend and obtain a full registration for it.
Background on Paladin
When tankmixed with the fumigant chloropicrin, Paladin has performed as well or better than a methyl bromide-chloropicrin blend in hundreds of field trials, says Andrew Horvath, global business manager for Arkema Inc., King of Prussia, Pa.
Nevertheless, he recommends that growers try the new fumigant on small acreage initially to learn how it will perform under their specific conditions.