MUSKEGON, Mich. (AP) — The state of Michigan has announced a quarantine to protect trees from an Asian insect that has killed millions of hemlocks across North America.

The agriculture department recently announced the hemlock woolly adelgid quarantine. The pest has been found along Lake Michigan in the Lower Peninsula in Allegan, Muskegon, Oceana and Ottawa counties.

The announcement means the state is regulating the shipment of hemlock nursery trees in and out of the four counties as well as the movement of hemlock forest products.

The state says the infestation is related to nursery stock brought into Michigan from eastern states prior to 2002.

——Online:Invasive and exotic species in Michigan