LANSING, Mich. (AP) -- The Michigan Department of Agriculture and Rural Development has established a quarantine to protect the state's nearly 14 million fir trees from an invasive insect.
The quarantine announced Monday generally prohibits shipment of fir nursery stock and fir timber products into Michigan from states infested with balsam woolly adelgid.
Michigan says certain low-risk fir products are exempt, including Christmas trees and wreaths and heat-treated timber products.
The quarantine also allows fir seedlings grown under an active pest management program to be shipped into Michigan.
The balsam woolly adelgid feeds on sap and weakens trees, eventually killing them.
It arrived in the U.S. from Europe in the early 1900s and is blamed for millions of fir tree deaths in North America, harming the timber and Christmas tree industries.