Arboriculture: History and Development in North America

"The worms are a public nuisance--and they kill trees"

-- Massachusetts housewife, 1869

About twenty years after the first Arbor Day and the founding of the Arnold Arboretum ( 1872), a new problem destined to have a significant impact on the development of arboriculture became apparent for the first time. The first major insect problem for North America--the gypsy moth--is one of the most damaging, persistent, and expensive pests in the history of arboriculture.

The gypsy moth (Lymantria dispar) is of European origin and earlier was known as Porthetria dispar L. It was brought to the United States in 1868 or 1869 by Leopold Trouvelot. Trouvelot was a noted French artist, naturalist, and astronomer, interested in experiments with silkworms. Trouvelot was then living in Medford, Massachusetts, a suburb of Boston, where he was trying to produce silk from native American silkworms, and had introduced European species for the same purpose. He brought gypsy moth eggs in egg masses from Europe to use in crossing the gypsy moth with the silkworm to produce hybrids. It was hoped that such hybrids would enhance the production of silk, or at least, provide a new fiber source. Interest in this subject had been stimulated by the unavailability of cotton in the northern United States during the Civil War.

During a violent, evening windstorm, a cage housing a small number of larvae (described as a "handful") was smashed, allowing the larvae to escape into the nearby woods of a vacant lot. After the moths had gotten away, Trouvelot became deeply concerned about the possible consequences and tried to alert the local

-79-