Sanctuary Spotlight: Thornapple Lake

Thornapple Lake Nature Sanctuary is one of MNA’s many inland-lake sanctuaries, protecting roughly 60 acres of lakeshore where the Thornapple River enters the Thornapple Lake in Barry County. The densely forested sanctuary would be a tempting destination for hiking and exploration if not for the wet terrain making trails impractical. This type of habitat, which floods every spring, is known as a floodplain forest.

The low banks along the Thornapple River allow for the natural fluctuations in water levels.

The Thornapple River, a major tributary of the Grand River which drains into Lake Michigan, travels nearly 90 miles through primarily agricultural land, and is disrupted at several points by man-made dams built to control its frequent flooding. From the tributary east of Charlotte until it joins Thornapple Lake the river flows freely, though with the appearance of a creek.

This floodplain forest area is therefore an important part of the landscape. Floodplain forests serve an important role in increasing natural water quality as pollutants get filtered out of the floodwaters through the soil. They also provide critical habitat for several rare birds, such as Baltimore Oriole, Cerulean Warbler and American Woodcock. The saturated soils of floodplain forests thaw earlier in the spring than surrounding soils, creating critical opportunities for early migratory birds to find food on their way to summer breeding grounds.

A great blue heron hunts along the shoreline at Thornapple Lake Nature Sanctuary.

The area around Thornapple Lake, however, has become heavily developed over the years with waterfront homes and neighborhoods which intersect the shoreline. The development impacts the ability of waterfowl and other species to use the lake for feeding and breeding. Concerned with the overdevelopment of the lakeshore, Richard and Rosemary Shuster donated the land that has become Thornapple Lake Nature Sanctuary in 2009.

Many of MNA’s Nature Sanctuaries are known for being incredible destinations for hiking with spectacular overlooks, abundant spring wildflowers, and more. But sanctuaries like Thornapple Lake are a reminder that prioritizing the protection of Michigan’s rich natural heritage for wildlife and not just human enjoyment, is just as worthwhile.

Why We Burn

Sanctuary stewards in safety gear stand over a patch of scorched ground at Butternut Creek Nature Sanctuary.

Seán Mullett, Sam Brodley, and Lance Rogalski pause for a moment while conducting a prescribed burn at Butternut Creek Nature Sanctuary.

April is traditionally the peak of burn season in the land stewardship world. You’ve probably noticed more controlled/prescribed burn photos filling up your social media feed; people dressed in yellow, flames and smoke over charred ground. But for as much of the media coverage as these burns get, you don’t often see the stories behind the need for them.

Controlled burns can take place for a number of reasons – to treat and manage invasive species like autumn olive, or in some prairie environments, to prevent trees and shrubs from encroaching and crowding out essential sun-loving wildflowers and prairie plants. Over the past month, MNA stewards conducted prescribed burns at several of its sanctuaries, including Butternut Creek Sanctuary in Berrien County, the goal of which was to maintain the open grassland features of the prairie fen. Prairie fens are critical habitat for a high number of imperiled and declining species including the federally endangered Mitchell’s Satyr, one of the rarest butterflies in the world; known only to exist in Midwestern fens that were created by the retreating glaciers. While the Mitchell’s Satyr has not been observed at this particular sanctuary for a number of years, maintaining healthy prairie fen communities like that found at Butternut Creek is essential to improving threatened, fen-dependent species across the state.

In an excerpt from MNA’s spring 2011 magazine, Conservation Director Andrew Bacon explains:

Historically, fire crept through the understory of the forest, but did not necessarily ignite the mid- or upper-levels of the canopy as observed in the intense wildfires of recent times. Prior to human settlement, fire prevented shade-tolerant trees from populating oak-hickory forests, oak barrens and open communities. Without fire, trees like red maple, American beech, basswood and elm survive in the understory and fill gaps in the forest canopy.

As gaps are filled, less sunlight reaches the forest floor, making it impossible for shade-intolerant species like oak and hickory to grow. Herbaceous prairie and savanna species also become shaded out as trees become established. Slowly, the entire species composition of natural communities changes, and many species of plants and animals must find food and habitat elsewhere.

Prescribed fires have had significant and measurable results, such as restoring and protecting the habitat of the federally-endangered Karner blue butterfly. Without active management to keep these critical habitats healthy, these species and other habitat specialists like them would be at greater risk of decline.

2018 Year in Review

A Year of Milestones

2018 Year in Review Cover

Two major anniversaries distinguish a busy and exciting 2018.

The first, of course, is the 45th anniversary of the Michigan Nature Association’s campaign that prevented logging of the largest stand of old growth white pine left in Michigan and established our Estivant Pines Nature Sanctuary in 1973. The drive to raise needed funds to secure Estivant galvanized individuals, organizations and service clubs from all over the state and still stands as one of MNA’s crowning achievements.

In that spirit, we were delighted to receive a $90,000 challenge grant in honor of the Estivant Pines anniversary, and this new campaign is underway as this Year in Review goes to print.  With your generous support, we will add 60 more acres to this iconic nature sanctuary and direct $90,000 in challenge dollars to stewardship needs in our nature sanctuary network.

2018 is also the 45th anniversary of the federal Endangered Species Act.  The Endangered Species Act is an essential, national framework for protecting rare, threatened and endangered species but it has been under assault since its passage in 1973.  2018 was no different and we made our voice heard by stepping up to formally oppose rule changes that could have a devastating impact on the statute. We will continue to monitor and act on threats to this critical environmental law.

One of the major limitations of the Endangered Species Act, however, is the lack of funding for protecting critical habitat.  Remarkably, twenty years before Congress passed this landmark legislation, MNA’s founders recognized the need for action to protect Michigan’s rarest and most vulnerable species and natural communities, pioneering the strategy of protecting land in Michigan to do so.  We pursue that mission every day thanks to their foresight and our members and donor who continually rally to the cause.

Celebrating these two major milestones bookend a year’s worth of notable activities that you will read about in this Year in Review.  None of our work is possible without the commitment of our members, donors, and volunteers, and I hope you are as proud as I am of what we have accomplished together.  Be it saving old growth white pines in the Keweenaw, protecting imperiled natural communities across our great state, or defending critical policies for threatened and endangered species, we are truly all in this together.

Thank you for all you do—I look forward to another year of working with you to protect Michigan’s incredible natural heritage.

Garret Johnson
Executive Director

 

Pulling Spotted Knapweed at Five Lakes Muskegon Nature Sanctuary

By Abby Pointer, MNA Intern

IMG_2038Tucked away behind an interesting little trucking company, Five Lakes Muskegon Nature Sanctuary is a true sanctuary. A hidden, untouched, and thriving ecosystem where you would least expect it. In June, the Michigan Nature Association held a scheduled workday dedicated to the upkeep of this sanctuary. Five Lakes Nature Sanctuary consists of rare habitat, composed mostly of coastal plain marsh. I was told by the stewardship coordinator, Sam, that some of the plants found in the sanctuary are isolated communities that are typically found in marshes on the Atlantic coast. Thinking about the ecological reason as to how these plants managed to find a home in Michigan makes protecting these rare communities all the more important.

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Invasive spotted knapweed

The nature sanctuary not only contains coastal plain marsh, but also other critical habitats such as oak-pine barrens and dry sand prairies. The reason for our workday was focused on preservation of the dry sand prairies, which are susceptible to invasive species such as spotted knapweed. This invasive plant thrives in the soft, sandy soil. Spotted knapweed uses allelopathic chemicals to inhibit surrounding plant growth by exuding the chemical from its roots. For the critical habitat that the Five Lakes Nature Sanctuary protects, allowing this invasive species to spread would be detrimental to the rare marsh plant and wildflower communities.

The workday was led by West Michigan Regional Stewardship Organizer, Sam Brodley, and was attended by the two stewards of the sanctuary. What was unique about the stewards was that they were both young teenage girls. It was cool for me, as an aspiring female conservation biologist, to see young girls actively engaged in natural resource management. My mom and I arrived at the work day a little late, so we missed the group heading to the work site. Not knowing which direction they headed, we ended up going on a bit of a walk in the opposite way. While we missed some of the actual work, we were able to explore some of the sanctuary that we otherwise wouldn’t have seen. The trail we were on followed the marsh area and ran deeper into the woods as opposed to the dry sand prairie that we hoped to find. Though we enjoyed the scenic detour, I eventually contacted Sam and found our way to the right place.

IMG_9602The area we were working in was an open area, with sparse trees and shrubbery. Nothing stood out to me at first as clearly invasive, as sometimes plants do when they begin to overtake an area. One of the women who attended the workday told me that once you know what spotted knapweed looked like, you’d see it everywhere. She was very correct. It took me a second to become familiar with the plant, but soon I could spot it amongst other prairie like plants. The plant has a pale green, ashy complexion, which makes it stand out against native species. We were also told to look for its compound leaves to help distinguish it from similar prairie plants. Since the soil was so loose and it had recently rained, it was easy to pull the entire plant, taproot included, from the ground. We were lucky that the knapweed had not flowered yet, so we didn’t have to worry about bagging or burning the discarded plants.

When we had felt like we had made solid progress, we made the walk back to the cars and parted ways. Attending a workday, though shortened by an unfortunate case of misdirection, was a great way to feel involved with the nature of Michigan, even in places you’d least expect it. I got a great breathe of fresh air, and now I will always know how to spot spotted knapweed!

Check out MNA’s event calendar for find a volunteer workday near you!