Weed warning issued during field day at Marianna
Aug. 12, 2008Contact Information:
Claude Kennedy, Director, Lon Mann Cotton Research Station
870-295-2839 / ckennedy@uaex.edu
Ken Smith, Weed Scientist, Southeast Research and Extension Center
870-460-1091 / smithken@uamont.edu
By Fred Miller, University of Arkansas Division of Agriculture
479-575-5647 / fmiller@uark.edu
Ken Smith, weed scientist for the University of Arkansas System’s Division of Agriculture, talks about the spread of glysophate-resistant weeds in Arkansas during a field day Aug. 7 at the Lon Mann Cotton Research Station.
Guest speaker Larry McClendon of Marianna, chairman of the National Cotton Council, right, speaks with Mark Cochran, director of the Arkansas Agricultural Experiment Station, and entomologist Tina Teague during a field day Aug. 7 at the University of Arkansas System Division of Agriculture’s Lon Mann Cotton Research Station.
MARIANNA, Ark. — Pigweed, johnsongrass, horseweed and giant ragweed are all showing resistance to glyphosate herbicides in Arkansas, said Ken Smith, weed scientist for the University of Arkansas System’s Division of Agriculture.
Pigweed is becoming a big problem for Arkansas agriculture, Smith told an audience of farmers and agricultural businessmen during a field day Aug. 7 at the Division of Agriculture’s Lon Mann Cotton Research Station.
Smith held up a 3-foot-long specimen of pigweed. “We sprayed this plant three times with Roundup,” he said, adding that the specimen was found in Lee County, where Marianna is located.
Smith said glyphosate-resistant pigweed is spreading quickly. The area where the weed was found in 2007 was twice that of 2006.
Smith is conducting trials with various alternative herbicides in combination with glyphosate. So far, he said, results have varied and researchers are still looking for an effective combination. For now, he said, “If you have resistant pigweed in your fields, use a combination of glyphosate and another herbicide for best results.”
Pigweed seed is not spread by wind, Smith said, so good management makes a difference. “Even if your neighbor doesn’t take care of his fields, your diligence will keep your fields clean unless you have water moving off his land onto yours.”
Pigweed seed moves with water or soil, Smith said. “When you look at how glyphosate-resistant pigweed has spread, it follows the rivers,” he said.
In other topics covered at the field day, visitors heard a summary of research projects at the station, a report on late season water and insect management in cotton, research on stretching fertilizer dollars, management practices for corn and grain basis and marketing issues.
Guest speaker Larry McClendon, a Marianna cotton farmer and ginner, and chairman of the National Cotton Council of America, spoke about the council’s activities in helping to formulate the new Farm Bill, negotiating trade and supporting agricultural research.
The Delta Area Health Education Center of the University of Arkansas for Medical Sciences provided free health screenings for blood pressure, blood sugar and body fat. Cholesterol screens were offered for a fee. Dermatologist Dr. Jessica Pillow provided free skin cancer screenings.