Hemlock Woolly Adelgid Surveys 

A Tree Worth Saving

As part of the upper Midwest, Michigan is characterized by many different species of conifer trees that form an evergreen blanket across the state's northern landscape. One of these beloved evergreens is the eastern hemlock (Tsuga canadensis). Hemlocks are identified by their grooved bark, short needles with silvery undertones, and long, drooping branches. Often found along ravines, hillsides and stream banks, the eastern hemlock offers habitat for wildlife and provides shade for streams, effectively lowering stream temperatures and increasing oxygen for fish and other aquatic species. It is estimated that there are over 100 million mature hemlocks in the Great Lakes State. Unfortunately, this beautiful tree is now under threat from an invasive species: the hemlock woolly adelgid (Adelges tsugae). 


Hemlock Woolly Adelgid

Hemlock woolly adelgid (HWA) is a small insect that is obligate to hemlock trees. The pest feeds upon the stored energy reserves of hemlocks at the base of the needle. Over time, this action kills needles and branches, and can kill a hemlock tree in as little as 4-10 years if left untreated. As adults, HWA are small, flightless brown insects. As young, HWA is recognizable in white, fluffy ovisacs, at the base of hemlock needles during the winter months. Originally native to East Asia, HWA was accidentally brought to eastern North America in the 1950's; since then, it has spread throughout eastern North America and decimated hemlock populations throughout the Appalachians. Now, it has made its way to Michigan, putting the state's hemlock population at risk. 

What Is Being Done? 

To answer this oncoming threat, the Nature Conservancy is facilitating a survey and detection project along the 500 mile coastline of eastern Lake Michigan. Surveys are conducted primarily along shoreline areas, as the main vectors for this species are believed to be people and birds. Every CISMA along the lakeshore is participating in this project. From November - March, the CAKE CISMA field crew is actively taking requests for surveys, cost-free to landowners and partners through this grant project.



Do you have hemlocks on your property? To request a free survey, print off the downloadable pdf and return it to us by mail at our address,

4820 Stover Road Bellaire MI 49615, or over email at cakeisst@gmail.com. Please contact us at (231)-533-8363 (ext. 5) with any questions. 


Do you have Eastern Hemlocks?

The CAKE CISMA is offering free surveys of hemlock trees for invasive hemlock woolly adelgid (HWA). Property owners within 10 miles of Lake Michigan can contact  us at cakeisst@gmail.com or 
231.533.8363 or to request a free survey.