Winter 2024

NATURE NOTES Nature Notes is the Minnesota Scientific and Natural Areas Program quarterly newsletter. In this issue: Icelandite Coastal Fen SNA is a glimpse into Minnesota’s ancient past and vibrant present DNR staff explores methods of controlling smooth brome in native prairies Site Highlight: Kasota Prairie SNA Donate to the SNA Program Staff Highlight: Natasha Nemmers Site steward notes Events

Icelandite Coastal Fen SNA is a glimpse into Minnesota’s ancient past and vibrant present

By Justin Vorndran, SNA Communications Outreach Specialist

The shoreline of Lake Superior at Icelandite Coastal Fen SNA, with its pink rhyolite pebble beach and bedrock outcrops. Photo by Arika McGraw, MN DNR.

Icelandite Coastal Fen can be a peaceful place, with waves rhythmically rolling over smooth rhyolite pebbles, and spruce trees waving in the wind off of Lake Superior — but this unique natural area is a product of continent-splitting volcanic forces, crushing glacial activity, and over a billion years of stories to tell. When we explore Minnesota’s natural history, Icelandite Coastal Fen SNA is a great place to start.

The first question is fairly obvious — what does this spot in northeastern Minnesota have to do with Iceland? The answer lies under your feet. John Green, a retired geology professor at University of Minnesota Duluth, first spotted icelandite, a type of volcanic rock, in this area in the late 1960s, when he noticed unique bedrock in a roadcut nearby. “[Icelandite] is medium to light brown, with scattered small, whitish feldspar and dark pyroxene phenocrysts,” Green described the bedrock at the Icelandite Coastal Fen dedication ceremony in 2024 — “I recognized it as something special”. “Pyroxene phenocrysts” and “feldspar” are essentially spotty crystals and mineral deposits dotting the otherwise smooth, gray bedrock. The name “icelandite” was coined by British geologist Ian S. E. Carmichael in 1960, while conducting research at an active volcano in – you guessed it — Iceland. Carmichael was watching fresh icelandite forming, but the bedrock at Icelandite Coastal Fen SNA predates his observations by 1.1 billion years.

The bedrock at Icelandite Coastal Fen formed during a geological event known as the Mid Continental Rift. Approximately 1.1 billion years ago, the continent that would become North America was in the process of splitting in two. As the continent split, magma from deep inside the earth bubbled to the surface and cooled, forming the volcanic rocks that are now a hallmark of northeastern Minnesota, such as rhyolite, basalt, and of course — icelandite. This region is one of the only places where bedrock from the Mid-Continental Rift is on the surface, and icelandite is rare among these rocks. Visiting Icelandite Coastal Fen SNA is a great opportunity to set foot on some ancient history!

Exposed bedrock outcrops can be seen at Icelandite Coastal Fen SNA, such as this one in a colony of blooming bunchberries (Cornus canadensis). Photo by Arika McGraw, MN DNR.

However, this SNA preserves more than bedrock — a rare and fragile coastal fen can be found here, on the shores of Lake Superior. Fens are wetlands that rely on groundwater to form. The constant upwelling of water keeps this wetland saturated and allows a unique community of plants to thrive. In fens, the process of decomposition happens slowly, which can lead to the formation of a thick layer of dead plant matter called peat. This thick peat layer supports sphagnum mosses and a variety of unique plants. Right: Three-leaved false Solomon’s seal (Maianthemum trifolium) is one of the wildflowers that can be found at Icelandite Coastal Fen SNA. Photo ©ColdSnap Photography.

Fens don’t form overnight — it takes many generations of plants to form a peat layer. In many ways, a fen is a library of biological history. Each layer of peat records a growing season of plants and wildlife, undisturbed by the processes of decomposition. This ecological community is rare in the area, and Icelandite Coastal Fen is one of only two known fens on the north shore, and the only one directly adjacent to the lake.

Peering into the fen reveals a diverse, wet community of sedges, shrubs, and moisture-loving trees. Photo by Kelly Randall, MN DNR

Above all, Icelandite Coastal Fen SNA is a reflective place. Walk upon bedrock formed in explosive volcanic episodes a billion years ago and listen to the sounds of waves rolling over the rhyolite pebbles. Consider the thousands of cycles of birth, death, and birth again that have contributed to forming the peat in this coastal fen, all the while listening to the fleeting calls of migratory birds following the lakeshore. Icelandite Coastal Fen SNA is both an excellent place to explore a unique piece of Minnesota’s natural history and spend a reflective moment observing its vibrant present-day.

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DNR staff explores methods of controlling smooth brome in native prairies

By Dustin Graham, Natural Resources Specialist, Minnesota Biological Survey

Prairies face threats from a number of invasive species, but one with the most potential to oust a large majority of the native plant diversity from mesic to dry-mesic prairies is smooth brome (Bromus inermis). This reduction in plant diversity threatens biodiversity at all scales from soil microbes to insects, birds, and mammals. The prevalence of smooth brome has increased drastically in the last decade for a variety of reasons. As land managers increasingly focus on controlling smooth brome, SNA and Minnesota Biological Survey staff have set out to examine methods to manage smooth brome invasion in prairies.

Seedhead of smooth brome (Bromus inermis). Photo by John M. Randall, The Nature Conservancy, bugwood.org.

The scientific literature is relatively sparse on effective management techniques for smooth brome, and most of what does exist focuses on spring fire to control invasions. Observations of private landowners successfully maintaining prairies with haying and the historical use of many high-quality prairie sites as hay ground prompted us to explore the use of haying as a smooth brome management tool. As such, we decided to compare spring haying, fall haying, and biannual spring fire as methods of reducing smooth brome and recovering native biodiversity in remnant prairies. Right: The first spring prescribed burn of the biannual burn plots at Rock Ridge Prairie SNA in 2021. Photo by Judy Elbert, MN DNR.

We selected sites that had over 25% foliar cover of smooth brome, with a mix of native species present, and sites where we could find a producer willing to work within our timeframe. In the end, we set up the experiment on four sites: Mound Spring Prairie SNA, Rock Ridge Prairie SNA, and two Native Prairie Banks in the Minnesota River Valley.

A portion of each site was split into 4 blocks and different treatments were assigned:

• Spring haying between the 15th of May and the 15th of June each year.
• Spring prescribed burn between the 15th of May and the 15th of June every other year.
• Fall haying between the 15th of September and the 15th of October each year.
• No treatment (control group).

Hay bales after the first year of fall haying in October 2019 at Mound Spring Prairie SNA. Photo by Fred Harris, MN DNR.

We sampled vegetation within the blocks by placing 20 sampling locations in each block. In 10 of these we recorded all species present within 1 m2. At all 20, we counted the number of brome tillers (new shoots of grass) in 0.1m2. We sampled yearly from 2019 (before any management had taken place) to 2024 (the final year with no management). Right: A vegetation sampling plot at Rock Ridge Prairie SNA after three years of haying. Photo by Dustin Graham, MN DNR.

We plan to write up a scientific publication this winter, but early results suggest that spring fire and spring haying may reduce brome abundance over time, while the impacts of fall haying are less clear. Tiller counts for spring burn plots averaged 26 in 2019 and were down to 18 in 2024. Spring hay plots started at 16 and were down to 12, while fall hay plots went from 18 in 2019 to 20 tillers in 2024 and the control plots from 21.7 to 26. These results are more drastic in the smooth brome cover estimates that were taken at the beginning and end of the study (both years with no fire or haying management). In 2019, all plots had between 41 to 47 % cover of smooth brome. In 2024, smooth brome cover was down to 12% in spring hayed plots, 15% in spring burned plots, 24% in Fall hayed plots. Spring haying and biannual spring fire appear to be effective at reducing smooth brome, with mixed results for fall haying.

While biannual fire reduced brome after two burn cycles, there is some complexity in those results. The first burn occurring in 2021, resulted in little impact on brome tiller counts (from 20 tillers in 2020 to 21 tillers in 2021). The second burn in 2023 reduced brome tillers by around 40% (down to 12 tillers in 2023). There may be many reasons for the differences in impacts that spring fire had including the amount of rainfall. One potential reason that needs further investigation has to do with how brome responds after a burn. During field work, we noticed that many more brome tillers were flowering than typical in the year after a spring burn. It is possible that biannual fire was taking advantage of this response. The second fire cycle may have impacted brome more heavily while it had lower energy reserves from heavy flowering the year before.

All three treatments appear to have increased native species richness (the number of native species found in a 1m² plot), but there were some differences in whether forbs or graminoids were favored. Comparing 2019 to 2024, fall haying may have increased forb diversity, increasing by 1.1 additional species found per 1m². Meanwhile, spring prescribed burns and spring haying appear to have favored graminoids, increasing by 1.4 and 1.5 species respectively.

We’d like to extend our gratitude to our private partners who let us work on their Native Prairie Bank easements and to those who conducted hay management on research sites.

Site Highlight: Kasota Prairie SNA By Justin Vorndran, SNA Communications Outreach Specialist

It’s difficult to share the experience of visiting Kasota Prairie Scientific and Natural Area in words. Describing the size of this mesic prairie – 45 acres – might give you a sense of how long it will take to walk across it, but it won’t communicate the countless natural processes, seen and unseen, that you will encounter on a hike in this SNA. I could count up the thirty years that this place has been designated as a Scientific and Natural Area, but those years are a blink of an eye compared to the centuries of history living in the bedrock and soils of this place. Prairies can be subtle, and if I can’t describe the experience of walking among the waving grasses at Kasota Prairie SNA in just words – your visit to this place will be unique, and your connection with the prairie entirely your own.

Early summer at Kasota Prairie SNA. Photo by Fred Harris, MN DNR.

Mesic prairies like Kasota Prairie SNA were once the dominant plant community in southern Minnesota, but examples of prairie in the region are few and far between today. Prairie has largely disappeared as land has been converted to cropland, homes, and other uses. Prairies are home to a diversity of plants, which support wildlife and insects, as well as healthy soil and clean water. “Mesic” refers to a plant community that contains a moderate amount of moisture, and in prairies like Kasota, water availability can vary across topography and throughout the seasons. Mesic prairies are diverse — dominated by grasses like big bluestem, Indian grass, and prairie dropseed. Kasota Prairie SNA’s biodiversity significance is rated as “outstanding” by the Minnesota Biological Survey – this SNA preserves habitat for a number of plants, insects, and birds, some of which are rare. Throughout the year, varying blooming flowers mark the changing of the seasons on the prairie. Pasqueflowers and prairie violets are hallmarks of early spring, which give way to lush blooms of butterfly-weed, coreopsis, and more as summer begins.

Late summer at Kasota Prairie SNA. Photo by Justin Vorndran, MN DNR.

Left: Pollinators exploring the blossoms of rough blazing star. Photo by Justin Vorndran, MN DNR. Connecting with a prairie is a unique experience in the art of noticing, wandering the open space where an incredible natural community is playing out beneath your feet, through the seasons. Late summer blooms are especially spectacular, as I found out during a walk through the prairie this year. Like any visit to an SNA, a hike at Kasota Prairie SNA starts with clean boots, as the seeds of invasive species can travel in the laces and treads of shoes. The August air was heavy and thick with the rich scents of plant life – pollen, fragrant grasses, and wildflowers filled my nose.

A rainbow of late-season blooms peppered the field with vibrant gold and pink hues. Stiff sunflowers (Helianthus pauciflorus) and rough blazing star (Liatris aspera) are common sights on the prairie in late summer. Hundreds of wood-nymph butterflies (Cercyonis pegala) flitted around me as I waded through the grasses, and the sounds of bees excitedly crawling in bergamot blooms filled my ears. Erratics – large boulders deposited by the movement of glaciers – pepper this prairie and served as islands to navigate by as I waded through the thick, waist-high prairie.

Kasota Prairie SNA preserves native plant communities for future generations, promotes Minnesota’s biodiversity, and offers a wonderful opportunity to visit and experience a prairie. A place like this can’t be summarized in words – it can only be fully understood by experiencing it for yourself.

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Donate to the Minnesota Scientific and Natural Areas Program!

Showy Lady’s-Slippers (Cypripedium regina) at Iron Spring Bog SNA. Photo by Kelly Randall, MN DNR.

You can support the preservation of natural places for future generations by donating to the Minnesota SNA program! Your donation supports management and stewardship of natural areas, research to better understand Minnesota’s natural heritage, and the acquisition and designation of new Scientific and Natural Areas.

Staff Highlight: Natasha Nemmers

Photo courtesy of Natasha Nemmers, MN DNR.

Natasha Nemmers is a Scientific and Natural Areas technician in northeast Minnesota based out of Eveleth. She has worked with the DNR since July 2024, and she has enjoyed exploring new SNAs, and completing projects to improve natural areas. Her work so far has revolved around invasive species management, sign maintenance, deer exclosure repairs, and more. Natasha is looking forward to getting involved with prescribed fire efforts, conservation easement monitoring, and habitat improvement projects.

What is the best part about your job (and why)?

The best part about my job is that it takes me to so many cool places! I love the Northeast region of Minnesota and how different many of the landscapes are. I had never even heard of a Scientific and Natural Area before I found this job, and I think it’s amazing that I get to call the bogs, islands, and old growth forests of the North Shore my “office.” I literally tell my friends and family that my job is to maintain and improve the coolest places in Minnesota!

Why do you do this work?

I love to do this kind of work because it keeps me outside enjoying nature. There’s always something new you see or experience when you work outdoors. I am fortunate to have worked a few different internships and seasonal jobs in the natural resources field and have so many fond memories from each of them. I am very excited to see where this job takes me, as I’ve had many fun experiences in the 3 months I’ve been here.

What is your favorite native Minnesota plant or animal (and why)?

This is a tough one, but I’d have to say the black bear. First off, they’re adorable. More importantly, they are such intelligent and charismatic creatures. I had previously worked with black bears, and I learned so much about their species just by observing them. Seeing them, even though it’s usually only for a few seconds, is always an exciting experience for me.

What do you like to do outside of work?

In my free time I enjoy a variety of outdoor activities such as hunting, fishing, rockhounding, hiking, skating, cross country skiing, and camping when I can. If I’m not out in nature I can usually be found crocheting, crafting, or taking too many pictures of my dog and cat. Since moving to the Iron Range a few years ago, I have also taken up curling!

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Notes from Site Stewards

Canada yew (Taxus canadensis) within a deer exclosure in Chisholm Point Island SNA. Photo by Hans Kaldahl.

Site stewards monitor SNAs across Minnesota. Their observations provide valuable information to the SNA Program. Summer visits were regularly reported, with a variety of observations and tasks completed.

• Dean Frieler noted signs of a variety of wildlife including deer, bears, eagles, and songbirds at Gully Fen SNA this October. He also saw a few hunters out enjoying the SNA.
• In early November, Chisholm Point Island SNA site steward Hans Kaldahl spent the day inspecting deer exclosures and making repairs. He spotted a few young Canada yew growing in the exclosures that were put in place to help protect the yew. This is the first time he’s seen these seedlings since starting as a site steward.
• In mid-October, Townsend Woods SNA site steward Steven Gahm and Chamberlain Woods SNA site steward Paul Bulger teamed up to remove invasive buckthorn at Townsend Woods SNA. They spent over 2 hours removing buckthorn on the western side of the woods. Steven also spent time cutting seed-bearing buckthorn and honeysuckle earlier the same week. In late September, Townsend Woods SNA became one of the newest SNAs added to the Old Growth Forest Network’s national network of old-growth, native forests.

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SNA Events

Looking for a fun way to get outdoors and give back this winter? Join us for adventures and stewardship activities at SNAs! See the complete list on the SNA events calendar.

• 01/18/2025: Mindfulness snowshoe at Chisholm Point Island SNA.
• 01/25/2025: January Stewardship Event at Lost Valley Prairie SNA.
• 02/07/25: Sunset Snowshoe at Burntside Islands SNA.
• 02/22/2025: February Stewardship Event at Lost Valley Prairie SNA.

In Memory of Wayne Feder

Wayne Feder was a resident of Blue Earth County and an avid birder and naturalist who dedicated his time and money to preserving a plot of native prairie that has since been designated as Butternut Valley Prairie SNA. Wayne passed away on October 6th, 2024, and his efforts as an educator, coach, and naturalist will always be remembered. Read more about Wayne's contributions to Butternut Valley Prairie in the fall 2024 edition of Nature Notes.

Nature Notes is the Minnesota Scientific and Natural Areas quarterly newsletter (archive online). It seeks to increase interest, understanding and support of natural areas while promoting involvement in the protection of these special places. Contact us directly at sna.dnr@state.mn.us.

Funding for this project was provided by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR).