Compared with other members of the insect world, butterfly and moth larvae are not especially "aggressive," nor are they such rapid breeders and strong flyers as insects from the order Diptera, such as flies and mosquitoes. Most moths and butterflies produce only one new generation per year, and only a minority are likely to attack crops in swarms.
從整體昆蟲世界看來，蝶、蛾幼蟲並沒有特別的「攻擊性」，比之蚊子、蒼蠅等繁殖力高、飛行力強的雙翅目昆蟲，大部份蛾與蝶一年才一代，其中也只有少數種類喜愛團體活動、可能群起「危害」作物。