The female adult moth is gray and cannot fly. The male is a small brown moth with wings. The first cold snap in early winter alerts the adult moths to leave their in-ground cocoons. This usually occurs during the third or fourth week in November. The female crawls up any vertical object (all species of trees, houses, street lights, etc.) determined to reach the highest point possible to lay thousands of eggs on twigs and branches. This climbing habit is why the tree banding practice of treatment is used. When the female is trapped on the way up, we prevent the laying of thousands of eggs. The more traps installed, the greater the reduction in theĀ caterpillar population in the spring.