An eradication program in Missouri's Bootheel aims to remove a long-time pest.

Among economic crop pests, the cotton boll weevil ranks close to the top. The little beaked bug is expensive to control--and does even more costly damage when it isn't controlled.

With the idea that the best defense is a good offense, cotton growers in Arkansas and Missouri have launched battle plans to rid their fields of boll weevils once and for all. Boll Weevil Eradication Programs (BWEP) are now underway on some 1,450,000 acres of cotton in both states. Producers in all seven cotton-growing counties in southeast Missouri two years ago voted to begin a BWEP there. At about the same time, cotton growers in Clay, Greene and western Craighead counties in Arkansas passed a BWEP referendum. Eradication programs got underway earlier in other Arkansas districts.

With some variations, the Arkansas and Missouri programs are based on USDA eradication guidelines, designed to eliminate 90 percent of the weevil each year. The Missouri program is overseen by the Southeastern Boll Weevil Eradication Program of Montgomery, Ala., and the Arkansas program is being run by the Arkansas Boll Weevil Eradication Foundation at Little Rock.

However, these are locally initiated, locally controlled projects. Both required a two-thirds majority vote of cotton producers in each county or part of a county in the respective eradication districts. In both Arkansas and Missouri, BWEP got underway with a diapause spray in late summer, 2001. The Arkansas program is designed to get rid of the weevil within 5 years, and the initial producers' assessment is $24 per acre to pay costs. Missourians set up their BWEP on a 7-year timetable, with a per-acre assessment of $12.50 per cotton acre.

However, as weevil numbers decline, producers in each eradication zone will opt to go into a "maintenance" phase, with less intensive trapping and less frequent insecticide sprays, and per-acre costs are expected to decline to $6 to $8.

"This district is divided into units of about 15,000 acres, each with a unit supervisor," said Jaye Massey, Arkansas BWEP district supervisor. "We have slightly different protocols in different units, but generally, we make sprays based on the number of weevils caught in pheromone traps; all sprays are determined by weevil catches. We begin trapping early--to have traps out when weevils begin to emerge--and we start spraying when cotton is at the pinhead square [early bud] stage.

"We already have 8,694 traps deployed on about 32,000 acres, and all traps are checked weekly," Massey said. "We treat the field where weevils are trapped and all neighboring fields. In 2002, we sprayed some fields as many as 16 times."

The insecticide of choice is Malathion ULV, applied aerially.

"As long as there are pinhead squares in a field, the weevil has something to feed on and a place to lay eggs," Massey added. "We continue directed sprays until we determine that a cotton field can no longer serve as a host to the weevil, or until traps indicate that there are no more weevils in the field."

In Arkansas and Missouri, BWEP managers enter weevil trapping results into a computer data base. At any given time, the data base alerts supervisors to areas of most active weevil emergence.

"The BWEP program is based on careful trapping and timely spraying, but good record-keeping is vital," said Dewey Wayne King, supervisor of the Missouri BWEP district. "We need good, useful records to be able to find and recognize any chronic weevil hot spots before they become real problems."

King believes late-season weevil control is critical to eradication.

"We want biology and climate to help us as much as possible," he said. "We stress stalk destruction after cotton harvest. If we don't leave the weevil anything to feed on, it will be in poorer shape to survive the winter. Those weevils that do make it through winter must eat within a few days or die. Weevils need cotton to feed on and they must be near a cotton field to reproduce. We want to take those opportunities away."

Now in the second full year, how are the Arkansas and Missouri BWEPs performing?

"It's an expensive program, but it's working very well," said Roger Stokes, cotton grower and crop consultant in Clay County, Ark. "We're seeing less weevil pressure this year than last."

"Our early weevil emergence this year was 30 percent lighter than in 2002," said Dewey King, of the Missouri program.

Not every producer--in Arkansas or Missouri--is entirely happy with the programs. And, they sometimes blame weevil eradication for other problems. For example, 2002 saw the worst tobacco budworm infestation in recent years, in both states.

"Some cotton growers blame the budworm outbreak on Malathion sprays to eradicate boll weevil," said Mike Boyd, University of Missouri entomologist at the Delta Center. "They believe Malathion killed off beneficial insects that would otherwise have helped keep the budworm in check. And Malathion is hard on beneficials. But last year's weather played a bigger role in the budworm explosion. A combination of conditions contributed to the outbreak; weevil eradication practices were only a minor part of it."

"Whatever the reason for the tobacco budworm problem in 2002, it sold a lot of BollGard cotton here in 2003," said Roger Stokes, referring to cotton that incorporates Monsanto's BT gene which is toxic to budworms and bollworms.

Both Missouri and Arkansas BWEP efforts are being hampered to some extent by neighboring cotton producers. Growers in the Northeast Delta zone (Mississippi County and that part of Craighead County lying east of the St. Francis River) have repeatedly turned down BWEP referendums. To the extent that cotton farmers in the Northeast Delta fail to control the pest, this provides a 350,000-acre boll weevil "nursery" next door to both Missouri and Arkansas BWEP districts.

The Arkansas Boll Weevil Eradication Foundation periodically runs weevil traplines across the state, recording weevils captured. For the week ending May 3, 2003, the Foundation's results showed only five weevils captured in the Clay, Greene and western Craighead district. By comparison, 415 weevils turned up in traps set in the Northeast Delta region.

"Our trapping shows that we are getting some infiltration in those areas of Dunklin and Pemiscot counties that abut Mississippi County, Ark.," said Dewey King.

Earlier this year, the Arkansas State Plant Board put regulatory wheels in motion to force Northeast Delta growers into an eradication program, by invoking a 1917 Arkansas "nuisance" pest and plant protection law.

"Our goal is to make the boll weevil history in a major part of the Mid-South," said King. "But how well we succeed depends on what happens with weevil eradication across the rest of the Cotton Belt."

Jaye Massey agreed: "This is a good program and it's working, thanks to a lot of dedicated cotton growers. In effect, we're trying to work ourselves out of a job, and if we have our way, within a few years, you'll have to go to a museum to find a boll weevil."