Squares damaged by egg-laying or feeding will flare in about 3 days after puncture, but squares may remain on the plant for 5 to 7 days before falling to the ground. Cycles are repeated during the season until cotton plants are destroyed or killed by frost. Theoretically, the off-spring from a single pair of weevils could amount to 12 million in one year but probably number about 2 million. Control of Overwintered Boll Weevils Emergence of boll weevils starts with warm days in March and continues until July or later, depending on temperatures and moisture. Peak of emergence normally occurs in late May or early June.
Weevils can survive on seedling cotton but can reproduce only on fruiting cotton.
Overwintered-weevil populations will be lower than subsequent populations in untreated cotton. Proper timing of effective insecticides can lower this population, thus reducing in-season weevil problems. The recommended action threshold is 25 weevils per acre. To determine the number of weevils per acre, examine all plants on 50 feet of row in five locations in the field and multiply the number of weevils counted by 50. If one or more weevil is found in the sample, you have an action threshold .