The use of Dimilin for controlling cotton insects has been associated with enhancing maturity and increasing yields. A review of results between 1979 and 1982 indicated blocks treated with Dimilin were ready for harvest 11 days earlier and yielded 85 lbs. lint/acre more than the grower's standard insecticide program, when multiple applications of Dimilin were made for boll weevil (Anthonomus grandis). Preemptive applications of Dimilin for beet armyworm (Spodoptera exigua) or fall armyworm (Spodoptera frugiperda) control at 5 sites in 1997 resulted in an increase of 73 lbs. lint/acre. At one site, where potential differences in crop maturity were documented, cotton treated with Dimilin matured 14 days earlier. Possible explanations for these observations will be discussed.