The Michigan Department of Agriculture and Rural Development announced the quarantine Monday, which generally prohibits shipment of fir nursery stock and fir timber products into Michigan from states infested with balsam woolly adelgid.
"This pre-emptive quarantine is designed to prevent the massive losses of native firs that have occurred in other states," department Director Jamie Clover Adams said in a statement. "We don't want to see places like Tahquamenon Falls or the Pictured Rocks lakeshore suffer loss of thousands of fir trees that grow there."
Michigan said that 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.
"While we don't have BWA in Michigan, it could be introduced into the state's landscape in a number of ways, including on infested nursery stock, firewood, logs and vehicles and then spread by wind, birds and other animals which can carry it for miles," Clover Adams said.
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.