White egg sacs of the hitchhiking hemlock woolly adelgid. Courtesy photo.
By Emily Cook
I did not grow up in northern Michigan. My home, a few hours south, was tucked next to state park acreage in the middle of the state. The landscape was of rolling hills previously cleared for row crops. Despite being a “nature kid,” who later went on to get a degree in conservation, I cannot tell you if we had any hemlock trees. I can close my eyes and walk the same trails in my mind that I did when I was 10 or 11. I see monstrous beech trees, towering maples and quaking aspen leaves, but the dark-green needles of the eastern hemlock tree elude my memory. I’m sure the trees were there, more sporadic and as a rarity, but they are mostly reserved for shorelines.
When I relocated to Manistee County nearly five years ago and began to explore the natural areas, hemlock trees moved to the forefront of my mind. Entire swaths of forest are shaded with these incredible evergreens. After a new snowfall, a favorite spot to rest during a winter hike is where dense hemlock stands provide natural shelter against the elements. If you pause and look up, you can see birds flit from branch to branch. Creeks and rivers are often lined by hemlocks and provide essential shade to the aquatic world below. Catch the setting sunlight filtering through them and it is practically magic.
As my eyes follow the birds, however, I am also subconsciously searching for any sign of something that should not be there. Author and environmentalist Aldo Leopold wrote, “One of the penalties of an ecological education is that one lives alone in a world of wounds.”
I have felt this weight since I began working with invasive species more than a decade ago. If I am hiking during peak spring ephemeral season in May, I am always scanning for garlic mustard. As I shop at garden centers for vegetable seeds and wildflowers, I notice the stockpile of invasive Japanese barberry. While my breath catches every time I walk within a grove of native hemlock, my brain has also been trained to think of the threat to them. In this case, an invasive insect called hemlock woolly adelgid (HWA).
I am not writing this to tell you about all the bad things lurking in our landscapes. One of my greatest pleasures is exploring our forests, lakes, dunes and shorelines, even with the knowledge that a lot of what I am seeing could be problematic. However, I think it’s possible to move beyond the “world of wounds” by joining forces and working to protect our special places. I have become certain of one thing while living in northern Michigan – many of the people who live or visit here are truly passionate about the health of our land, water, and the plants and animals that live here.
Stopping the spread of hemlock woolly adelgid is just the sort of battle that can be won with the unified efforts of passionate people. This aggressively hostile insect has been creeping its way north along the Lake Michigan shoreline, and it was most recently discovered in Ludington State Park in Mason County. It is small and wingless, and resource managers believe it is unintentionally hitchhiking on recreational vehicles – think the top of a camper brushing the branches of a hemlock tree in Grand Haven and then driving north to another campground. In a new location, the adelgid uses its sharp, piercing mouth parts to suck nutrients from hemlock stems and twigs. Die-off is gradual and can often take more than five years, which is why there is hope. Treatment is possible, unlike most cases of another invader – the infamous emerald ash borer.
Catching hemlock woolly adelgid populations early is critical. It is the reason I cannot help but scour pine needles when I should otherwise be enjoying a hike with my dog. Eastern Hemlocks are special, not only to me, personally, but because they are such a critical component of the ecosystem. They also protect dunes and riparian systems from erosion. The northern Michigan landscape is scattered with thousands of them, a pocket of forest among the estimated 170 million hemlock trees across the state. Losing them is too heartbreaking to consider.
State-wide efforts are currently underway to stop HWA in its tracks. Locally, the Northwest Michigan Invasive Species Network (ISN), along with partners within the Michigan Department of Natural Resources, the Nature Conservancy, Forestry Assistance Program, the Sleeping Bear Dunes National Lakeshore and more, are teaming-up to conduct surveys along the Lake Michigan shoreline.
This is where you can get involved. Learn how to identify the signs of HWA. Focus your eyes upward as you pass beneath a hemlock grove on your next snowshoe hike. (Winter is the best time to spot the ovisacs, or egg sacs.) Watch for signs of a sick tree. Clean your camping gear and vehicles before moving to another location. Little acts of vigilance can make a big difference.
To see if you qualify for a free site visit to your property, go to: www.HabitatMatters.org/hemlock-woolly-adelgid.
As I wandered through Arcadia Dunes last night, I paused at one of my favorite spots. The trail loops along a short ridge and in winter you can look down into a snowy valley. The light is dim, shrouded by branches of mature hemlocks. The ridge puts the tree branches at eye level and, as always, I flipped a few over, just to check. Nothing. Only a bit of snow falling and landing at my feet. A poem by Robert Frost slipped into my mind:
The way a crow
Shook down on me
The dust of snow from a hemlock tree
Has given my heart
A change of mood and saved some part
Of a day I had rued.
A reminder that time spent in the woods is practically magic, and hemlock trees are worth fighting for.
Emily Cook worked as Outreach Specialist for the Northwest Michigan Invasive Species Network. She and her husband reside in Arcadia and can often be found exploring nearby trails with their two collies.
