SNA Nature Notes - Summer 2018

minnesota department of natural resources

Minnesota Scientific and Natural Area


Showy lady's-slipper

Summer 2018

Minnesota’s Blufflands Landscape 

Ancient and Remarkably Diverse

By Hannah Texler, Plant Survey Supervisor, Minnesota Biological Survey


I am lucky enough to have spent a lot of my time while working for the Minnesota DNR in the Blufflands in the southeast part of the state.  It’s become one of my favorite parts of Minnesota.  

Also referred to as the driftless area or coulee country, this is a landscape at once majestic and intimate, ranging from vertical cliffs and wide vistas to narrow valleys, winding creeks, and a myriad of different habitat niches. Despite the relatively small size of this landscape compared to others in Minnesota, the biological diversity here is higher than in any other part of the state!  Minnesota’s endangered, threatened, and special concern species list includes 189 plants and animals that reside here. The region also has the highest number of animal species of greatest conservation need in the state. 

Bluffland habitat at Mound Prairie Scientific and Natural Area
Bedrock bluff prairie and mesic hardwood forest at Mound Prairie Scientific and Natural Area. Photo by Kelly Randall

If geography and ancient history ruled, southeast Minnesota would probably be a separate state combined with parts of neighboring Wisconsin, Iowa, and Illinois. Together, these 18 million acres are called the Paleozoic Plateau. It sits on top of layers of bedrock formed over 250 million years ago under a vast sea. After the sea receded, glacial streams—which eventually became the Mississippi River and its tributaries—carved into the bedrock and created a hilly, dissected landscape. Much of the bedrock was composed of limestone and dolomite. Water and other natural forces shaped these soluble rocks into caves, sinkholes, and underground drainage, creating a type of topography known as karst.

The Paleozoic Plateau was largely missed by the last glaciers to move across the state. So instead of being covered by glacial sediments like most of the rest of Minnesota, this rugged ancient landscape is still visible today. 

Why is this region of the state so packed with diversity? Part of the answer lies in its varied topography—steep slopes, floodplains, groundwater seepage areas, high ridge tops, and cliffs. These landscape features support native plant communities specially adapted to thrive under those conditions.

And why so many rare species?  One factor is Minnesota’s position at the northwestern edge of North America’s Eastern Broadleaf Forest Province. Many of the species found here are rare in the state because they are at the western or northern edge of their range. For example, in Minnesota the timber rattlesnake (Crotalus horridus) is found only in the Paleozoic Plateau, but this species ranges more widely throughout eastern North America in appropriate habitats. The blufflands provide an ideal mix of habitats for these snakes—forests and prairies for summer habitat, and rock outcrops for winter dens.

Some rare aquatic species are at the northern edge of their range in southeastern Minnesota. One is the crystal darter (Crystallaria asprella), a small, pale-yellow fish of large clear-water streams with moderate to swift currents. For a handful of rare species, the blufflands are key to their survival: Seven rare species have their primary range here in special habitat conditions. Glade mallow (Napaea dioica) is a tall, summer-blooming floodplain plant that is endemic to the region, meaning it is found nowhere else in the world.

The blufflands of southeastern Minnesota.
The blufflands at Whitewater WMA in southeastern Minnesota. Photo by Hannah Texler

Native Habitats 

Bedrock bluff prairies are also known as goat prairies because their extreme steepness seem best suited for goats to climb.  This unique blufflands habitat occurs on south- to west-facing slopes, where dry conditions slow the growth of trees and shrubs. Fires historically helped to keep these areas open and dominated by over 200 species of native grasses and wildflowers.

Wooded slopes and ridge tops surround the goat prairies. Red oak, white oak, bur oak, and shagbark hickory are some of the characteristic trees of these fire-dependent forest communities.

On cool north- to east-facing slopes and on narrow valley floors along streams and seeps, a variety of forested plant communities are found. Mesic hardwood forests are dominant, with canopies of sugar maple, basswood, red oak, and often white pine, especially on rocky upper slopes. Here, cool, shady conditions make fires much less frequent. Thick layers of leaf litter break down to build up deep, loamy soils rich in nutrients. Before tree buds unfurl in spring, carpets of spring-ephemeral wildflowers cover the forest floor.  One of these, the diminutive white-flowered squirrel corn (Dicentra canadensis), is found nowhere else in the state.  By summer, the ground is covered by many of the 40 species of ferns that occur in the blufflands together with later-blooming wildflowers.  

Higher up the slopes in the coolest, rockiest valleys, habitat remnants from the last ice age persist. Here, winter ice stays in the limestone bedrock crevices well into summer.  Air moving through these rock fissures is cooled and slowly melts the ice. Where cool air and icy water emerge, thick moss carpets and northern plants grow.  Balsam fir, Canada yew, and the endangered Iowa golden saxifrage (Chrysosplenium iowense) occur in these places. These northern plants are remnants from 10,000 years ago when the climate was colder and these species more common.

Tiny snails discovered here, know only previously from the Pleistocene era, depend on the continuous presence of cold air, reside on many of these slopes. One federally threatened plant, Leedy’s roseroot (Rhodiola integrifolia ssp. Leedyi), is known from only seven places in the world—four of them on these persistently cold cliffs in Olmsted and Fillmore counties.

These cliffs and slopes are extremely fragile places—one misstep could send rocks, snails and plants (or a person) tumbling downhill.

Another mosaic of native plant community types resides along the region’s big rivers, including the Mississippi and its major tributaries the Root, Zumbro, Cannon, and Vermillion rivers. Their floodplains hold marshes and sedge meadows, as well as floodplain forests dominated by silver maple, green ash, cottonwood, river birch, and swamp white oak.

More than 150 bird species breed in or migrate through the floodplain habitats. Nearly half of North America’s songbirds and 40 percent of its waterfowl spend at least part of their lives in the Mississippi flyway. Bright-blue cerulean warblers (Setophaga cerulea), brilliant yellow-orange  prothonotary warblers (Protonotaria citrea), and soaring red-shouldered hawks (Buteo lineatus) are some of the birds at the western edge of their range here.


This article is an excerpt from a story first published in the Minnesota Conservation Volunteer.


Brownsville Bluff Scientific and Natural Area
Mesic hardwood forest and the City of Brownsville from Brownsville Bluff Scientific and Natural Area. Photo by Kelly Randall

These Scientific and Natural Areas in the blufflands allow you to see these native habitats for yourself: 

 SNA Interpretive Naturalist: Welcome Paula!  

The SNA Program is excited to welcome Paula (PJ) Comeau to the program! Paula has begun work as an SNA Interpretive Naturalist for northwestern Minnesota. Her work will include leading educational events and engaging volunteers throughout the summer!  Paula has a Ph.D. in Natural Resource Management and a passion for connecting others to the outdoors. 

Paula (PJ) Comeau
Paula (PJ) Comeau

How did you become interested in the outdoors?

I am originally from South Dakota where I was raised on a farm/cattle ranch on the Standing Rock Reservation. It has been in our family since the 1800s. Being a farm kid and basically an only child (my brother is 11.5 years older than I am), I spent a lot of time exploring the outdoor world. The world I had to explore was truly beautiful, and to this day I’m convinced that when people talk about God’s country they are referring to north-central South Dakota. Conservation has been part of our farming operations since the 1950’s. 

What are your goals for this summer?

My goals are to increase awareness of our Scientific and Natural Areas programming and participation on SNA’s. I would also like to expand our volunteer opportunities into stewardship, volunteer programs and training for our local natural resources management and environmental science students and the Women in Conservation organization.

What’s the best part about your job? 

I love leading people into natural areas and allowing them the opportunity to explore nature the way their ancestors would have several hundred years ago. I am excited to help introduce (and reintroduce) people to outdoor spaces. I love bringing people together who are already active in the outdoors with people who want to learn how to be active in the outdoors!

What is your favorite SNA 

Right now I would have to say that Blanket Flower Prairie is my favorite SNA, but I’m still exploring my SNA’s and that may change as I see more!

Site Highlight: Prairie Coteau SNA

By Carly Gelderman, SNA Web and Social Media Specialist


This SNA is part of a larger landform, the Coteau des Prairies, or ‘prairie highlands’ left between the paths of two ice sheets of the Wisconsinan glaciation of North America. The 20,000 square mile plateau is in parts of southwest Minnesota, southeast South Dakota and northwest Iowa. These prairie highlands have inspired painters like George Catlin, who created Pipestone Quarry on the Coteau des Prairie in the 1830s, and more recently, artist Terry Redlin, who was born and raised in the region and has been known as “America’s most popular artist”. 

Within this stunning region is Prairie Coteau SNA, a 420-acres natural area comprised of slopes of deep stony till (unsorted glacial sediments) deposited from 18,000-12,000 years ago and flat ridges covered in loess (fine, windblown glacial sediments). This SNA is a rare prairie habitat that was once much more common, and now plays a vital role in supporting upwards of 60 grasses, sedges and rushes, and over 200 wildflowers, including puccoons, prairie smoke, wood lilies, prairie phlox, blazing stars, asters, goldenrods, sunflowers and the small white lady's-slipper!

Important for its inspiration and biodiversity, this SNA also plays a significant role in scientific study. The Minnesota Zoo's Prairie Butterfly Conservation Program is working to save endangered Poweshiek skipperling (Oarisma poweshiek) and Dakota skipper (Hesperia dacotae) butterflies. Prairie Coteau SNA is a potential reintroduction site for these species!

Prairie Coteau Scientific and Natural Area
Summer wildflowers on Prairie Coteau SNA. Photo by ColdSnap Photography

SNA Events

Summer’s bounty of SNA events await you. Pollinators? We've got that. Wildflowers? Of course. Stewardship events? Check. Art? YES!, even art. Join us for these exciting opportunities listed below.  A full list is available on the  SNA Events CalendarCheck back frequently as new events are added, including a number in the planning stages for the North Shore of Lake Superior!


Project Art for Nature Postcard
Project Art for Nature showing at the White Bear Center for the Arts July 19-August 28. Proceeds benefit the SNA Program!

Emerald ash borer volunteer in costume at the Minnesota State Fair

Volunteer Opportunity: Invasive Species Display at the State Fair 


The Department of Natural Resources is looking for volunteers to help at the Minnesota State Fair’s Invasive Species display August 23- September 3. Join the fun and help educate visitors about the problems of invasive species in Minnesota. Follow the links below for more information:  

  • Staff the Invasive Species Display! Talk with visitors about the impacts of invasive species and the actions they can take to prevent their spread. . This position is for those with knowledge of aquatic or terrestrial invasive species.
  • Staff the PlayCleanGo Pledge Area! Talk with visitors about the PlayCleanGo campaign and ways to prevent the spread of invasive species, ask visitors 2-3 survey questions, and give out free supplies. This position is for those with knowledge of terrestrial invasive species.
  • Wear the Emerald Ash Borer Costume! Greet visitors, give away educational materials, pose for pictures, and talk about preventing the spread of emerald ash borer. 

Contact Laura VanRiper at  for volunteer registration instructions. Volunteers will receive a free ticket to the fair for each day they volunteer.

Notes from Site Stewards

Site stewards monitor SNAs across Minnesota. Their observations provide valuable information to the SNA Program. Here are some interesting notes from recent reports:

  • Site steward Jordon Kjos checked the signs, parking areas, fencing and noted little recent animal or human activity at Pembina Trail SNA on March 3.
  • The volunteer stewardship event at Lost Valley Prairie SNA on March 24 went well. Volunteers logged a total of 53 hours, including the time of stewards Jim Smetana and Steve Poole. The crew cut then burned brush and were greeted by two Sandhill Cranes flying above the site. 
  • Trails leading to the Kawishiwi Pines SNA were brushed out recently. Co-site steward Martha McPheeters noted whoever had do the work had done a nice job when she visited on April 15.
  • On May 5, site stewards Jerry and Karen Ibberson continued a multi-year effort to remove invasive buckthorn and Dame’s rocket at Clinton Falls Dwarf Trout Lily SNA. The Ibbersons also spend many hours each year spring surveying rare wildflowers with the Minnesota Biological Survey.

Thanks for all the work you do for SNAs stewards!

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


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).