The recent discovery of hemlock woolly adelgid as far north as Ludington State Park in Mason County is a reminder of the importance of checking hemlock trees for signs of the invasive insect.
The Michigan departments of Natural Resources and Agriculture and Rural Development encourage those who have eastern hemlock trees on their property to take time this winter to inspect the trees for signs of hemlock woolly adelgid. Anyone taking to the woods can help by looking for signs of the insect while hunting, hiking or enjoying any outdoor activities.
Winter is the optimum time to look for evidence of an infestation, according to Robert Miller, MDARD’s invasive species prevention and response specialist.
“Cooler temperatures trigger feeding activity,” Miller said. “As hemlock woolly adelgids feed, they secrete a white, waxy material that creates ovisacs. The presence of these small, round, white masses makes it possible to identify infested trees.”
As they feed, these tiny, soft-bodied insects consume a hemlock’s stored nutrients, slowly sucking the life from the tree.
These insects are considered invasive because they are not native to the state and can cause significant harm to Michigan’s hemlock resource, estimated at 170 million trees.
Infestations of hemlock woolly adelgid have been confirmed in Allegan, Ottawa, Muskegon, Oceana and Mason counties, all bordering Lake Michigan.
Winter surveys underway
Throughout the winter, survey crews from several Cooperative Invasive Species Management Areas will take to the woods looking for signs of hemlock woolly adelgid. Surveys will be conducted within a 5-mile border along the Lake Michigan shoreline in both the Lower and Upper peninsulas.
At the same time, DNR staff will survey state parks and federal lands in the vicinity of Lake Michigan.
Because hemlock trees can be protected from these insects with proper insecticide treatments, infested trees and any