By Karla Arboleda
Researchers at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) are developing fumigant combinations to fight nutsedge. Nathan Boyd, an associate professor of horticulture at UF/IFAS, said options are limited when trying to control the weed.
“Nutsedge is a problem because it’s the only weed that punctures the plastic mulch that we use,” Boyd said. “Unfortunately in most vegetables … there are not a lot of herbicide options, so the only way to control it is with fumigants.”
PRODUCTS AND RATIOS
While a fumigant could show good results one year, it could be inconsistent during the next year. Boyd recommends using several products together.
“Combinations are the most effective,” Boyd said, adding that Pic-Clor 60 works best in this way. “If you add K-Pam to that mix, you get a more consistent level across time.”
Other products could also be useful for growers dealing with nutsedge. Fumigants like telone and chloropicrin are the two most common materials to use, and they work as a team.
“What I’ve been able to show is that having more chloropicrin in that mix can help guarantee that you kill more of the tubers,” Boyd explained. “Basically you have one (product) that stimulates sprouts, which makes them susceptible (to be) killed by the other one.”
“Really it’s about which product and what rate … it depends on what other pests you have,” Boyd said. “Just because something is really good on nutsedge does not mean it will control nematodes, for example.”
NEW FUMIGANTS
Recently, Boyd and his team have been working to establish new fumigants to fight nutsedge. They developed one that also hinders pathogens, like fusarium, but it’s not ready for use.
“XRC-245; that’s a new fumigant, and it’s very effective on nutsedge when combined with chloropicrin,” Boyd said. “We’re still trying to figure out how to best apply it … it’s so volatile that it’s hard to keep in the soil.”
Boyd vouched for one more fumigant that helps to fight other weeds, but is not yet registered. “EDN is another new one we’ve been working on for a few years; it’s probably the most effective one on broadleaf weeds and grasses,” Boyd said. “We’ve been collecting data to hopefully get it registered at some point.”