ANTRIM COUNTY – The Michigan Department of Agriculture and Rural Development (MDARD) has confirmed a new finding of the invasive hemlock woolly adelgid (HWA) near Torch Lake in western Antrim County. This marks the eighth county in Michigan to report an active infestation, joining Allegan, Benzie, Mason, Muskegon, Oceana, Ottawa, and Washtenaw counties.
Steve Carlson, MDARD’s Pesticide and Plant Pest Management Division Director, emphasized the importance of public awareness in combating invasive species. The recent discovery was made by a vigilant landowner who learned about HWA during an educational outreach event organized by the Charlevoix, Antrim, Kalkaska, Emmet County Cooperative Invasive Species Management Area.
Hemlock woolly adelgids are tiny insects that feed on hemlock trees, weakening needles, shoots, and branches. Infested trees exhibit slowed growth and a distinctive grayish-green appearance, with death occurring within four to 10 years if left untreated.
Identification of HWA can be done by examining the undersides of hemlock branches for white ovisacs resembling balls of spun cotton. However, it’s essential to distinguish them from other less harmful pests. Helpful identification resources and tips are available at Michigan.gov/HWA.
Carlson explained that HWA likely entered Michigan through infested nursery stock from northeastern states and can spread via wind or by hitchhiking on animals or vehicles. To prevent further spread, individuals are advised to park only in designated areas outdoors, clean gear and vehicles before traveling, and refrain from transporting firewood.
Suspected infestations in Antrim County or new areas of the state can be reported by:
- Emailing MDARD at MDA-Info@michigan.gov or calling the Customer Service Center at 800-292-3939.
- Using the Midwest Invasive Species Information Network (MISIN) online reporting tool or downloading the MISIN smartphone app and reporting from your phone.
Be prepared to report the location of infested trees and, whenever possible, take one or two pictures of infested branches to help confirm identification. To avoid spreading hemlock woolly adelgid, do not collect sample branches or twigs.
For more information on hemlock woolly adelgid and other invasive species in Michigan, and to find out what you can do to help prevent them, visit Michigan.gov/Invasives.
