If we should destroy the tents in the middle of a warm, sunny day, what would happen? Answer. The caterpillars, being out feeding on the leaves, would not be hurt, and as soon as they came back would make another tent.
If the tent is destroyed in the early morning or late afternoon or on a cold, dark day, what would happen? Answer. The caterpillars, all being in the tent, would be destroyed.
How may the tents be destroyed? Answer. By wiping them out with a long pole on one end of which is wound a rag saturated with kerosene. Or by burning them out with a torch.
Is it best to destroy the caterpillars early in the season, while they are still small, or to wait until they are large and are about ready to pupate.
If the trees were sprayed with Paris green in the early spring, what would happen? Answer. The caterpillars would be killed as soon as they began to eat, when they were first hatched.
When these caterpillars feed on the leaves of wild cherry they are doing no damage to an orchard. Therefore, when the tents appear on wild cherry trees have we any right to destroy them? Answer. The wise and careful farmer does not allow wild cherry trees to grow along his fences if they will become breeding places for insect enemies which will next year attack his orchards.
Fig. 149. The Curious History of a Tent Caterpillar. a, The masses of eggs on the twigs of an apple tree. b, The eggs enlarged. c, A full grown caterpillar. d, Cocoons. e, The moth, or adult insect.