Our Immigrant Insect Fauna

From the time of Asa Fitch in the mid-19th century American entomologists have known that many of our most serious crop pests were not native to North America. It is also common knowledge that a very large number of crop pests, present in other countries, have not yet gained entry to the United States. Each year the U.S. Department of Agriculture spends several million dollars on plant quarantine activities designed to insure that these foreign pests are not added to our North American fauna.