MISSISSIPPI STATE -- North Delta farmers did not pass the referendum to continue a maintenance program battling boll weevils on the first vote, but a cotton insect expert wants growers to consider the alternative before the second referendum begins the first of August.

Blake Layton, an entomologist with Mississippi State University's Extension Service, said it would not take boll weevils as long to infest the entire state in this century as it did in the early 1900s when they first arrived from Mexico.

"It took boll weevils seven years to go from Natchez to the northeast corner of the state, but that was a very different scenario than in the north Delta now. That was before boll weevils colonized the entire state," Layton said. "Now, we still have isolated occurrences, especially in the north Delta. Instead of seven years, growers may only be looking at two or three years for complete re-infestation. An additional difference is the increased opportunity for weevils to hitch rides from infested areas into new fields."

Significant changes in insecticide treatments in recent years also work to the boll weevils' advantage.

"One factor that would greatly facilitate a quick rebound in boll weevil populations is the widespread planting of transgenic Bt-cotton," Layton said. "Since its introduction in 1996, Bt cotton has resulted in large reductions in the number of insecticide treatments applied to control caterpillar pests, and this translates into less coincidental control of boll weevils."

The entomologist explained that before Bt, growers would include boll weevil treatments in four to seven sprays per year for caterpillar pests. Growers often had to make additional insecticide treatments just for weevils.

"Before Bt cotton and boll weevil eradication, growers may have applied six to nine insecticide treatments during a season. Current varieties of Bt cotton receive an average of less than two caterpillar sprays per season, and the future potential is for even fewer," Layton said.

Cotton growers in Bolivar, Coahoma, Washington, Leflore, Quitman, Sunflower, Tunica and west Tallahatchie counties will be voting Aug. 4 to 15 in a referendum that would place north Delta counties into a 10-year maintenance program after the five-year eradication effort concludes. A similar referendum garnered a 55 to 58 percent favorable vote in June. The referendum required more than a 66 percent vote for passage.

Growers will vote on annual assessments of not more than $12 per acre. Program managers hope actual assessments will be between $8 and $10 for the next couple of years, then drop even lower to $6 to $8 per acre. To have a valid referendum, 50 percent of the eligible growers must return ballots and more than 66 percent must vote in favor.

The current eradication program started in Mississippi's eastern counties in 1997 and progressed annually westward. The north Delta regions voted to join the five-year program in 1999.