Silent Spring

by Rachel Carson

these moths to escape from his laboratory in Medford, Massachusetts, where he was attempting to cross them with silkworms. Little by little the gypsy moth has spread throughout New England. The primary agent of its progressive spread is the wind; the larval, or caterpillar, stage is extremely light and can be carried to considerable heights and over great distances. Another means is the shipment of plants carrying the egg masses, the form in which the species exists over winter. The gypsy moth, which in its larval stage attacks the foliage of oak trees and a few other hardwoods for a few weeks each spring, now occurs in all the New England states. It also occurs sporadically in New Jersey, where it was introduced in 1911 on a shipment of spruce trees from Holland, and in Michigan, where its method of entry is not known. The New England hurricane of 1938 carried it into Pennsylvania and New York, but the Adirondacks have generally served as a barrier to its westward advance, being forested with species not attractive to it.