Japanese beetles were first found in the United States in 1916 near Riverton, New Jersey. Since then Japanese beetles have spread throughout most states east of the Mississippi River. However, partial infestations also occur west of the Mississippi River in states such as Arkansas, Iowa, Kansas, Minnesota, Missouri, and Oklahoma.
APHIS maintains the Japanese Beetle Quarantine and Regulations that can be found in 7 CFR 301.48. The objective of the Japanese Beetle Quarantine is to protect the agriculture of the Western United States and prevent the human-assisted spread of the beetle from the Eastern U.S. The federal quarantine is designed to reduce artificial spread of Japanese beetles by aircraft. The Western states protected by the Japanese Beetle Quarantine are: Arizona, California, Colorado, Idaho, Montana, Nevada, Oregon, Utah, and Washington.
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