162 AGRICULTURAL EXPERIMENT STATION. 



closed becomes a brown chrysalis and in about two to three weeks 

 the moth comes forth. The cocoon is shown in Fig. 11, d. 



LIFE HISTORY. 



The moths appear early in July and in a few days lay their eggs 

 upon the twigs as described above. Early in the spring when the 

 buds are opening, the eggs hatch. The caterpillars live on the 

 leaves and require about six weeks to mature. The}^ then spin 

 their cocoons from which the moth emerges in two or three weeks 

 completing the life history. 



REMEDIES. 



Pick off the egg clusters during the winter. Should any colonies 

 hatch in the spring as soon as the web is noticed, remove it late in 

 the evening or early in the morning when the caterpillars are at 

 rest. The nest may be reached with a ladder and taken off with a 

 gloved hand and the larva crushed ; or a bunch of rags can be tied 

 to the end of a pole and the nest removed. The orchard should be 

 examined from time to time for a month or six weeks. The worms 

 should be killed or they will climb the trees again. This pest has 

 quite a number of natural enemies which keep it in check. 



A minute Ichneumon fly only one twenty-fifth of an inch long is 

 parasitic on the eggs. One cluster of eggs examined last spring 

 hatched only about a dozen caterpillars and in a few days nearly 

 seventy-five of these small Ichneumon flies emerged. 



FIG. 12 



Fig. 12 represents a large Ichneumon fly that preys upon the 

 caterpillars. We hatched last spring from a cocoon an Ichneumon 

 fly shown in Fig. 13. 



