Boyd, who spoke Feb. 21 at the Joint Conference of the Mississippi Agricultural Pest Management Societies in Greenville, Miss., told attendees that the eradication program had successfully eradicated more than 90 percent of the pests from the 1.6 million acres of cotton planted statewide in 2001.
“We had 10 counties in the state with zero weevil captures in 2001,” he says. “There are still a few hotspots in the state, including areas in Adams, Jefferson, Grenada, Carroll, Montgomery, Bolivar, Desoto and Tate counties. But for the most part, we’ve seen very good progress in all of the eradication regions.”
The “no fly” order that was issued after the Sept. 11, 2001 terrorist attacks, and remained in effect for a longer period of time around cities such as Memphis, likely affected the number of boll weevils found in the “hot spots” located in Desoto and Tate counties.
“The no fly zone area did have a significant impact on the number of weevils trapped, but what kind of impact it will have on the number of treatments needed in 2002 is still to be determined,” Boyd says.
In the four-month period between May 9 and Sept.12, 2001, Boyd says, 0.005 weevils per acre were trapped in Region 1 and 0.008 weevils per acre were trapped in Region 2. In comparison, 0.04 weevils per acre were trapped in each of the two eradication regions during the six-week period that the no-fly order was in effect, preventing aerial applicators from operating around the Memphis area.
Despite this minor setback, each of the four regions has experienced a substantial reduction in weevil populations since boll weevil trappings were initiated. Experiencing the biggest drop in weevil numbers was Region 4 with 99.5 percent fewer weevils, followed by Region 3 with a 98.2 percent drop, Region 2 with a 93.9 percent decrease, and Region 1 with 92.8 percent fewer weevils trapped per acre.
According to Boyd, the Mississippi Boll Weevil Eradication Program trapped less than one weevil per acre, on average, in 2001. Breaking it down further, eradication personnel documented 0.13 to 0.26 weevils per acre in Region 1, 0.12 weevils per acre in Region 2, 0.15 to 0.35 weevils per acre in Region 3, and 0.03 weevils per acre in Region 4.
A big help to the program, Boyd says, was the weather during the winter of 2000-2001, which may have decreased the number of overwintering boll weevils.
Between the 2000 and 2001 crop seasons, the number of boll weevils infesting cotton fields dropped by 92.8 percent in Region 1, 82.2 percent in Region 2, 89.1 percent in Region 3, and 97.3 percent in Region 4.
In fact, Boyd says, the majority of Mississippi’s cotton acreage required less than one control treatment for boll weevils in 2001. Meeting treatment criteria for the eradication program were 29 percent of fields in Region 1, 28 percent of fields in regions 2 and 3, and 17 percent of fields in Region 4.
Looking forward to the 2002 season, Boyd says the eradication program’s goal this year is to completely eradicate the boll weevil from Mississippi cotton fields. “While we are striving for eradication in all four regions of the state, we plan to adjust our personnel and trap density in relation to the boll weevil populations, and treat those areas where weevils are found,” he says.
“Because the winter of 2000-2001 has put us on an even keel with boll weevil populations across the state, we plan to put many of our baited pheromone traps at 600-foot intervals, instead of the 350-foot spacing we’ve used previously,” Boyd says. “Our research data shows that a 600-foot interval is the widest space that will work in those fields that have not captured a single boll weevil from Aug. 1 to the end of the crop season. However, if these fields catch more than one boll weevil during the 2002 season, we anticipate that those field will be moved back to the 350-foot spacing.”