Catching the Prairie Bug

Catching the Prairie Bug

Catching the Prairie Bug!

Photos and Story by Jonathan Rigden

This story was featured as a guest column in The La Crosse Tribune. 

View of the Mississippi River from Marowski Bluff Prairie

Zoerb Prairie in Hixon Forest in August with rough blazing star blooming in the foreground. 

Do you know that prairies and oak savannas once filled much of the landscape in western Wisconsin and that only a tiny fraction remains? And that this tiny fraction is disappearing fast? Some readers may have heard of a group called The Prairie Enthusiasts. This organization is a nonprofit land trust that has chapters in Wisconsin, Minnesota, and Illinois and works throughout the tristate area to save as many of these relics from the past as possible. In doing so, we hope to preserve and grow this unique ecosystem that supports an abundance of special plants and animals. The Coulee Region Chapter of the Prairie Enthusiasts includes the counties of La Crosse, Vernon, Monroe, Buffalo, Trempealeau, and Jackson.

 

A prairie can escape the attention of those who have never been exposed to and noticed its wonders. But something out of the blue can spark an interest, like seeing a beautiful prairie flower for the first time or colorful bees hovering over a native thistle. Then, some susceptible individuals “catch the prairie bug” and a cycle begins. They identify the flower and one of the bees. On the next hike, they see another amazing flower with a delicate butterfly feeding on its nectar, look them up, and there you have it, they’re hooked! A cascade is launched- interest leads to learning leads to knowledge leads to more interest, learning, and knowledge and so on. And a fun-filled adventure awaits!

But all the beauty of the flowers, grasses, insects, birds, and other critters on the prairie can escape our interest without a spark. Like the fires that keep the prairies healthy, something must start this process. Fire is said to need three components to become self-perpetuating- fuel, oxygen, and heat. But you can have all the fuel, oxygen, and heat in the world and there won’t be a fire until a spark ignites the system. Our hikes, work events, and educational programs might be just the spark needed to set the your cycle in motion and, as we say, “Ignites your relationship with the land”!

 

Many of you might have noticed the cleared and sometimes burned areas on some of the bluffs in our area, including in Hixon Forest. The Coulee Region Chapter has been involved in many of these efforts while teaming up with other groups such as Friends of the Blufflands, the Mississippi Valley Conservancy, and the Wisconsin DNR. Despite this significant progress, there is still much to be done. Many bluff prairies in the Driftless Area continue to be taken over by red cedars or invasive nonnative plants like buckthorn. In a perfect “prairie world” all of these sites would be saved. That, of course, is unrealistic, but many can and should be saved before they are gone forever. This restoration and maintenance work could come from landowners, contractors, and volunteers but the effort needs to be guided and coordinated. In our six-county area, we hope that the Coulee Region Chapter can help lead this effort.  

 

So, as a new year begins and some of us think about our goals, perhaps one of them could be getting out, investigating the prairies near you, catching the prairie bug, and supporting the Coulee Region Chapter of The Prairie Enthusiasts by becoming a member and volunteering on our work days. Check out our chapter HERE and follow us on Facebook. 

 

Happy New Year!

Another Bluff Prairie Saved in The Driftless Area

Another Bluff Prairie Saved in The Driftless Area

Another Bluff Prairie Saved in The Driftless Area

By Sarah Barron

View of the Mississippi River from Marowski Bluff Prairie

View of the Mississippi River from Marowski Bluff Prairie

“I’m very happy to save this unique piece of land as it represents not only disappearing habitat but also the very character and uniqueness of the Driftless Area.” — Dr. Marowski, the generous landowner preserving a prairie for future generations.  

 

Ferryville, WI — When Dr. Marowski, a cardiologist living near Milwaukee, stood upon a steep bluff above the town of Ferryville, he was in awe of the stunning view. The Mississippi River, blue and majestic stretched below him, and to the north and south, the unique and ancient landscape filled the horizon. At his feet, he took notice of prairie flowers rarely seen any more and quickly understood the conservation value of the property.  

The diversity of life this bluff prairie holds will now be stewarded forever. In December 2023, Dr. Marowski generously arranged for the protection of his 11-acre property by The Prairie Enthusiasts, ensuring the land will be stewarded and enjoyed for generations to come. Additional support from Mississippi Valley Conservancy, the Natural Resources Foundation of Wisconsin and Wisconsin’s Knowles-Nelson Stewardship Program helped make this protection project possible. Dr. Marowski also gifted The Prairie Enthusiasts with a land management endowment, which will provide resources to steward the habitat far into the future.  

Stewardship of this prairie already began back in July of 2022. Working with Dr. Marowski, The Prairie Enthusiasts Coulee Region Chapter began restoration work on the bluff prairie. Volunteers removed some areas of sumac, red cedars and other aggressive vegetation from the site. There was already a healthy plant community there, with prairie plants like dwarf blazing-star and leadplant, as well as various birds, insects and reptiles that live on the site. The stewardship work that started and will continue in perpetuity will ensure this rare prairie ecosystem thrives.  

 

This land, now named Marowski Bluff Prairie, is situated between Rush Creek and Sugar Creek State Natural Areas and contributes to an important protection corridor linking them together. Even though the remnant prairie at the site is in outstanding condition, it will need consistent land stewardship to remove and prevent tree and woody brush encroachment, which can shade out prairie plants. Part of that stewardship will be returning fire to the site using prescribed burns at regular intervals. The Prairie Enthusiasts Coulee Region Chapter invites the public to participate in upcoming work parties no matter what your experience level. Work parties will be scheduled this winter as weather permits. Additional volunteer opportunities and field trips will be available in the future. Details about work parties and field trips will be posted on the events calendar on our website at ThePrairieEnthusiasts.org. 

 

About The Prairie Enthusiasts 

The Prairie Enthusiasts is an accredited land trust that seeks to ensure the perpetuation and recovery of prairie, oak savanna, and other fire-dependent ecosystems of the Upper Midwest through protection, management, restoration, and education. In doing so, they strive to work openly and cooperatively with private landowners and other private and public conservation groups. Their 11 regional grassroots chapters of volunteers in Minnesota, Wisconsin, and Illinois lead projects in their local communities focused especially on high-quality remnants, which contain nearly all the components of endangered prairie communities. Find more information at: ThePrairieEnthusiasts.org 

Help The Prairie Enthusiasts steward more land, provide education and more by making a donation today!

We All Have Mentors

We All Have Mentors

We All Have Mentors

By Scott Weber

November 13, 2023

Konrad collecting seed for the International Crane W Foundation at Muralt Bluff prairie, fall of 1980
We all have mentors in nearly everything we do, and restoration ecology is no exception. My mentor, Konrad Liegel, is a person you probably don’t know, but he had a profound influence on prairie restoration and reconstruction in both Minnesota and Wisconsin. He and I were both students of the late Dr. Paul Jensen who taught ecology, evolution, and field biology at Carleton College in Northfield, Minnesota. Paul convinced the college to buy McKnight Prairie, one of the best remnant prairies in western Goodhue County, to serve both as an ecology laboratory and a seed source for restoration projects. Konrad, a student from Plain, Wisconsin, wrote a thesis, “A Guide to the Carleton Arboretum Restoration Project,” a fairly comprehensive work. He, along with other enthusiastic students, began restoring a brome grass field, Hillside Prairie, with a combination of seed plots, seedling transplants, and a sod transplant experiment with the UW Arboretum’s Curtis and Greene prairies as models.

I was introduced to the prairie project in the spring of 1979 by volunteering for a burn. Back then, we had no burn permit, no official burn plan, and no equipment other than matches, rakes, water jugs, and wet burlap to use as fire swatters, but we did have a general notion of backfires and head-fires and which one to light first. By summer of 1979, the project consisted of two seed plots, 1978 and 1979 spring plantings about an acre a piece, plus the sod transplant area of much smaller size. Konrad graduated in spring of 1978, as did many of the student volunteers, so we were very dependent on the help of Dr. Jensen and Konrad’s thesis. I also checked out The North American Prairie, by Dr. John Weaver, and tried to use that to identify the grasses in the new prairie, not realizing that most of it was still brome grass. That is a revelation that most of us have had at some point: virtually all of the vegetation on our roadsides and farmland is not native to North America. Suddenly every prairie remnant, from McKnight to the big bluestem along the railroad right of way, was precious.

 

A geology professor, Dr. Ed Buchwald, became the first Arboretum Director and began hiring two to three students in the summer as Arboretum assistants in 1978, and I jumped at the opportunity to work in the Arboretum with my coworker, Dick Mertens, for the summer of 1979. We repaired the trail network from the erosion caused by runoff from the fields the college rented out but also pulled parsnip in the postage stamp prairie remnants, collected seeds for future plantings, watered transplants, and did other maintenance. As far as prairie restoration went, we were greenhorns. By spring of 1980, I was the “burn boss,” having completed only one other burn in my life, and no one else was primed to take over the project, so I needed some guidance. Dr. Jensen helped us identify plants and locate seed sources, but none of us had much experience starting a prairie from scratch, so I went in search of Konrad. I needed some education from the guy who wrote the book.

 

Konrad returned to Wisconsin after graduation to work for the Aldo Leopold Reserve (now Aldo Leopold Foundation) to construct a pre-European settlement vegetation map of the reserve. He also worked at the nearby International Crane Foundation (ICF) planting the first seed plots on ICF’s newly purchased farm. Konrad’s friend, Charlie Luthin, convinced ICF to include habitat restoration as part of their conservation message, and Charlie planted ICF’s first prairie at their old site closer to Baraboo. A crane disease outbreak at their first site accelerated ICF’s need for a new home, and the new site was a great opportunity to do some major restoration of prairie, oak savanna, and wetlands. Our Carleton Natural History Club visited ICF in March 1980, and I asked Konrad if I could be his intern for fall of 1980.

 

I took the summer of 1980 off from the Arboretum job at Carleton, backpacking with my roommate in the Grand Tetons and North Cascades, and arrived at ICF in mid- August. Konrad assigned me the task of completing the herbarium collection for the site, helping his summer intern, Shelly, finish mapping the oak woodland, writing a guide to prairie seed germination and storage, and, most importantly, collecting and cleaning seed for both a fall 1980 and spring 1981 planting. Konrad kept me very busy!

 

Back then fall plantings were very experimental and rarely done, so Konrad was taking a big chance, especially since future funding and dedication was never guaranteed. Then, as now, speed matters, and warm season grasses and black-eyed Susans come fast in a spring planting. Fall of 1980 was a wet season, and we harvested a bumper crop of prairie dropseed and many other species from Avoca Prairie, Muralt Bluff, Spring Green and Lone Rock remnants, the UW Arboretum, and wherever else we could find seed. Fortunately, being a non-profit, we had access to seed sources normally off limits to private individuals. If we had known then what we know now, the entire five acres should have been planted in the fall, not just the one-acre plot. The dropseed and most forbs, including the gentian seed collected at Avoca, have done very well there, whereas the spring planting became dominated by tall grass. In retrospect, we wasted a lot of good dropseed and forb seed by planting most of it in the spring.

 

I returned to Carleton and worked in the Arboretum again in the summer of 1981 with my coworker, Sue Peterson. Armed with all the knowledge that Konrad bestowed upon us, we not only did trail repair but also sampled the 1978 and 1979 seed plots, learning that brome grass percentage will decrease with fire and competition. We collected seed for another hillside planting, and, based on Konrad’s example at ICF, turned our attention to oak savanna. Saving all the savanna oaks suddenly became a top priority. Converting crop land to prairie before government programs like the Conservation Reserve Program (CRP) and government cost-sharing was difficult since the college needed the rental income, so Sue and I were free to hack away at the buckthorn and non-oak species in an opening Dr. Jensen’s students had studied and managed. That oak opening was the epicenter of the savanna project. Many thanks to Ed for letting us do that at the expense of some trail work.

 

We completed another seeding, about 1.5 acres, on Hillside Prairie and tilled up another acre or so to prepare for another. We contracted all the tillage work to local farmer, Palmer Fossum. Unfortunately, we didn’t have the results from the ICF fall planting, so we planted in spring. There are leadplants and other nice forbs still present after 40 years, but few, if any, dropseed or gentians in those plantings. Eventually the Arboretum Director became a full- time position with several students hired each year, but I’m not sure if Carleton would have as extensive a project as it has now without the vision and commitment of students like Konrad and professors like Paul and Ed. They deserve credit for getting the project going before the college could make a major financial investment.

 

Konrad also worked on other projects in Sauk County, especially the prairie along Highway 12 in front of the Badger Army Ammunition Plant as a member of the Sauk County Natural Beauty Council (SCNBC), part of a nationwide highway beautification program started by Lady Bird Johnson. After I graduated from Carleton, I worked for the Aldo Leopold Reserve, ICF, the Wisconsin Conservation Corp, and volunteered for the SCNBC board. I was either working for Konrad or following his footsteps. I learned almost every important lesson in prairie reconstruction then: the importance of good seed sources, the diversity of fall plantings, how quickly prairie species establish in nutrient poor soil, and the importance of record keeping. Konrad was also very humble; he knew that each of us is just a temporary link in a long chain of human interactions with our environment. We all have to pass the torch and move on at some point.

 

Unfortunately for prairies and ecological restoration, Konrad left his job with ICF to go to law school at Cornell and, soon after, moved to Seattle with his sweetheart, Karen, to gain experience in environmental law, and our paths diverged. Conservation has one of the highest education- to- pay ratios of any occupation, so law was probably the best career choice for Konrad, but not a field that I was suited for. I wanted to spend my time out on the prairie collecting seeds forever!

Meet a prairie mentor by attending one of our events! No experience necessary, and it’s a great opportunity to learn and connect with others that love the land.

Moths, Caterpillars, and Restoration of Remnants

Moths, Caterpillars, and Restoration of Remnants

Moths, Caterpillars, and Restoration of Remnants 

By Robert J. Marquis

October 1, 2023

Schinia lucens adult on leadplant, Blueberry Hill Prairie, photograph by Christopher Smith. 

The goal of The Prairie Enthusiasts is to preserve and restore prairies and savannas in the Upper Midwest.  By this we mean the protection of the entire ecosystem, not only the plants but also the animals and microbes and all their intricate interactions with those plants and each other. It has long been feared that conservation efforts might result in “empty forests” (or in our case, “empty prairies”) in which the landscape appears to be intact but close-up, many if not all the once known animal inhabitants are missing. A major challenge is to document the effects of prairie and savanna management on the animal participants and their place in prairie food webs.  

 

The St. Croix Valley chapter in conjunction with Minnesota Department of Transportation (MNDOT) has managed a small remnant prairie (15 acres) for 18 years. This prairie, known as the Blueberry Hill Prairie, lies on the western bluff  (Minnesota side) of the St. Croix River, just opposite Hudson, Wisconsin. Beginning in 2013, volunteers of the chapter began to convert 11 acres of adjacent agricultural land into prairie. In 2023, the chapter initiated efforts to document the interactions between insects and plants that occur in the Blueberry Hill Prairie.  

One particular interaction of interest is that between leadplant (Amorpha canescens (Fabaceae)) and the Leadplant Flower Moth (Schinia lucens (Noctuidae)) (Swengel and Swengel 2006). The Leadplant Flower Moth occurs from western Michigan to eastern Montana, south to Illinois, Iowa, Nebraska, and Oklahoma, and then again in Florida and South Carolina in the East, and in California and Arizona in the West (http://mothphotographersgroup.msstate.edu/species.php?hodges=11174). On July 6, 2023, Christopher Smith of MNDOT and Wayne Huhnke, a member of The Prairie Enthusiasts and steward of Blueberry Hill Prairie, searched the local population of leadplant on the prairie remnant for the Leadplant Flower Moth. After searching some over 500 plants, they found a single moth, which they photographed (Fig. 1). Surveys of lead plant at the Rocky Branch Prairie and the Foster Cemetery Conservation Area, both in the City of River Falls, Wisconsin, revealed no adults this year. The moth is bright mottled pink (Hess and Hatfield 2015, Henderson 2017), and therefore not easily missed 

Black light setup before sunset (left) and after in the dark (right). Photographs by R. Marquis

The Leadplant Flower Moth is endangered in Michigan (Michigan DNR 2023) and Indiana (Indiana DNR 2023), of special concern in Minnesota (Minnesota DNR 2023), and of greatest conservation need in Wisconsin (Wisconsin DNR 2023a). It is highly specialized in habitat, food plant, and phenology, and it is this combination of characteristics that makes it vulnerable. In the Upper Midwest, it is found only on prairie, caterpillars feed only on leadplant, and then only on the flowers and developing fruits of the plant. This lifestyle forces it into a very narrow time window of activity. In the Upper Midwest, we might suspect that caterpillars of this species could also survive and mature on fruits of Amorpha fruticosa (indigo bush), given that even highly specialized species often can feed on more than one member of the same plant genus. But there are no feeding records for A. fruticosa (Robinson et al. 2002), perhaps because that plant in Wisconsin and Minnesota grows in moist woodlands, along streams, and in floodplains. The moth does occur outside of the range of A. canescens, meaning that it must feed on additional host plant species.  

Late instar caterpillar of Schinia lucens, collected on leadplant at Blueberry Hill Prairie. Photo by R. Marquis
After finding the moth adult, the chapter held its first black-lighting event at Blueberry Hill Prairie on July 25, 2023 (Fig. 2). One goal was to attract more adults of this species to get a better sense of the population size. Schinia lucens adults are attracted to ultraviolet lights, establishing that they do fly at night (The Lepidopterist’s Society 1983, 1984). The other goal of black lighting was to more broadly survey the moth species that occur at that prairie. No Leadplant Flower Moths came to the lights that night, perhaps because it was past the flying date of adults. Using a beating sheet placed under lead plants, however, and gently shaking the plants, we were able to find two caterpillars suspected to be of the species. We reared one to a late instar, photographed it (Fig. 3), and then returned it to Blueberry Hill Prairie. The photos match those published online (identification by J. Sorgaard, pers. comm.). The caterpillar ate only developing fruits even though stems and leaves of leadplant were made available. At this time, seven other species of Lepidoptera are known to feed on leadplant parts (Hess and Hatfield 2015, R. Henderson, pers. comm.). None of them are sufficiently similar enough to confuse them with members of the genus Schinia 
Given the decimation of North American prairie, it is not surprising to learn that five of seven species of Lepidoptera (moths and butterflies) listed as endangered or threatened in Wisconsin are prairie and savanna species (Wisconsin DRN 2023b), and all nine endangered or threatened Lepidoptera species in Minnesota are of prairie or savanna (Minnesota DNR 2023). A twelve-year survey of prairie and savanna sites in the Chicago area never or rarely encountered 44% of the insect species that are considered prairie/savanna specialists for the region (Panzer et al. 2010). All is not without hope, however. Even small prairie remnants, if of high quality, are not “empty, as they can harbor prairie specialists (Panzer et al. 2010). In addition, restoration of prairie can be effective in augmenting species diversity and abundance. In Iowa, restored prairie begins to approach remnant prairies in moth diversity after seven years (Summerville et al. 2007). Restoration of prairie in Wisconsin, resulting in increased abundance of leadplant and the leadplant flower moth, further suggests that management can be an effective tool to recovering interactions (Henderson 2017). We will continue to monitor the status of Schinia lucens at Blueberry Hill Prairie, and at the other sites managed by the St. Croix Valley Chapter 

Citations 

Henderson, R. 2017. Of checks, balances & seed production. The Prairie Promoter 30:6,8. 

Hess, M., and M.J. Hatfield. 2015. One plant at a time. The Prairie Promoter 28:1,4. 

Indiana DNR. 2023. Indiana county endangered, threatened and rare species list. https://www.in.gov/dnr/nature-preserves/files/np-Indiana-County-Endangered-Threatened-Rare-Species-List.pdf. Accessed 30 August 2023.  

Michigan DNR. 2023. Threatened and endangered species list. https://www.michigan.gov/dnr/managing-resources/wildlife/wildlife-permits/threatened-endangered-species/threatened-and-endangered-species-list. Accessed 30 August 2023.  

Minnesota DNR. 2023. Minnesota’s endangered, threatened, and special concern species. https://www.dnr.state.mn.us/ets/index.html. Accessed 31 August 2023. 

Robinson G.S., Ackery P.R., Kitching I.J., Beccaloni G.W., Hernández L.M. 2002.  

Hostplants of the moth and butterfly caterpillars of America north of Mexico. Memoirs of the American Entomological Institute, v. 69, 824 p. 

Summerville, K.S., Bonte, A.C. and Fox, L.C., 2007. Short‐term temporal effects on community structure of lepidoptera in restored and remnant tallgrass prairies. Restoration Ecology, 15(2), pp.179-188. 

Swengel, A.B. and Swengel, S.R., 2006. Variation in detecting Schinia indiana and Schinia lucens (Lepidoptera: Noctuidae) in Wisconsin. The Great Lakes Entomologist, 39(3 & 4), p.6. 

The Lepidopterists’ Society. 1983. Season summary. News Lepidoptera Society, no. 2. 

The Lepidopterists’ Society. 1984. Season summary. News Lepidoptera Society, no. 2. 

Wisconsin DNR. 2023a. Species of great conservation need. Wisconsin wildlife action plan. https://dnr.wisconsin.gov/topic/WildlifeHabitat/actionPlanSGCN. Accessed 30 August 2023.  

Wisconsin DNR. 2023b. Wisconsin’s endangered and threatened species list. https://dnr.wisconsin.gov/topic/EndangeredResources/ETList . Accessed 30 August 2023.  

Want to stay up-to-date on events like this happening in the St. Croix Region? Send us an email to make sure you’re on their chapter email list.

Change & Persistence Among Prairie Grasses

Change & Persistence Among Prairie Grasses

Change & Persistence Among Prairie Grasses

Story and Photos by Dan Carter

There are many misconceptions about prairies that cloud restoration, reconstruction, and management. Prominent among these is the tallgrass prairie “big four,” a concept that situates big bluestem (Andropogon gerardii), Indiangrass (Sorghastrum nutans), switchgrass (Panicum virgatum), and little bluestem (Schizachyrium scoparium) atop the dominant hierarchy of plants on tallgrass prairie. The “big four” has far-reaching influence on grassland management, scientific study, and seed mix design. It’s Tallgrass prairie after all!  

The “big four” are indeed co-dominant in many places where prairie vegetation occurs today. But, except for little bluestem, they were not historically the most dominant grasses on much of the prairie landscape, nor are they most dominant on many of the best remaining old-growth prairies.  

John Curtis (1959)1 described the composition of the least disturbed old-growth prairies in Wisconsin. Big bluestem was present on all studied mesic prairies, but porcupine grass (Hesperostipa spartea), Leiberg’s panic grass (Dichanthelium leibergii), and prairie dropseed (Sporobolus heterolepis) were the most frequent grasses. Frequencies from Curtis are the percentage of square meter quadrats a species occurs within for a given community type — basically how likely the species is to be at your feet if you are  walking in the prairie. porcupine grass was twice as frequent on mesic prairie as big bluestem! Big bluestem was the fifth most frequent grass on dry prairies behind little bluestem, side-oats grama (Bouteloua curtipendula), long-stalked panic-grass (Dichanthelium perlongum), and prairie dropseed; and third most frequent on dry-mesic prairie behind little bluestem and side oats grama. Only on wet-mesic prairie was big bluestem the most frequent among the grasses. Still, on wet-mesic prairie little bluestem’s frequency was about three quarters that of big bluestem. Prairie cordgrass (Spartina pectinata) and Canada blue-joint grass (Calamagrostis canadensis) were the species most often present (frequency data lacking) on wet prairie.  

In Iowa, The only grasses noted by Ada Hayden (1919)2 among the “principal” species of prairie remaining on the gently rolling uplands (mesic) immediately north of Ames, Iowa were porcupine grass and prairie dropseed. Later, Brotherson (1969)3, Kennedy (1969)4, and Glenn-Lewin (1976)5 studied composition on three old growth prairies in northern and western Iowa and found prairie dropseed, Leiberg’s panic grass, and porcupine grass to be the most common on uplands at the respective sites.  

In the Red River Valley of NW Minnesota, Dziadyk and Clambey (1980)6 described old growth prairie communities dominated by blue grama (Bouteloua gracilis) and porcupine grass on dry ground, prairie dropseed followed by little bluestem on gentle slopes, little bluestem followed by prairie dropseed on moderately well-drained level areas, and big bluestem and slim-stem reed-grass (Calamagrostis stricta) together on low prairie over poorly drained soils.  

Weaver’s and Clements’ (1938)7 concept of “true prairie,” which they extend to a region stretching from Illinois to Nebraska and northwest Minnesota to Oklahoma, is co-dominated by mid grasses—Porcupine grass, prairie dropseed, rough dropseed (Sporobolus compositus), little bluestem, side-oats grama, and needlegrass (Hesperostipa comata, in the west). Weaver worked extensively on prairies in the western part of the tallgrass prairie during the first half of the 20th century, including early study of fire effects at the Agricultural Experiment Station just north of Manhattan, Kansas. There, little bluestem and Junegrass (Koeleria macrantha) were initially the top two grasses (big bluestem was third). Composition shifted toward big bluestem with annual late spring burning but not late fall burning or earlier spring burning8,9. Indeed, late spring burning in the western and southwestern tallgrass prairie region to promote big bluestem for cattle pasture is part of why prairie composition changed there during the 20th century. Weaver and Clements observed these changes occurring and attributed them to the grazing and burning practices of the time, saying that the result was “that their [the mid grasses’] tallgrass competitors, notably Andropogon, gradually moved up the slopes and today appear to be essential members of the prairie relicts(page 458).  

Why did European land use sometimes drive compositional change towards the tall grasses like big bluestem?  

Late spring burning favors the growth form of long rhizomatous, warm-season grasses. Their growing points remain below the soil surface until very late spring or early summer, so growth of their active shoots can continue uninterrupted despite damage to aboveground foliage with late spring burns. The growing points of most bunchgrasses (e.g., porcupine grass, prairie dropseed, Leiberg’s panic grass, little bluestem, Junegrass, etc.) rise above the soil surface and become vulnerable to fire shortly after they initiate growth. If these are burned off, the bunchgrasses must activate reserve buds to replace the lost shoots. That alone puts them at a disadvantage, but their reserves of buds tend to be small compared to long-rhizomatous big bluestem and Indiangrass10, so their regenerative capacity is sooner exhausted (meristem-limited) in response to removal of active shoots. The cool-season bunchgrasses are hit especially hard by late spring burning because of their early growth, but even little bluestem, a warm-season species, can be harmed by later spring burns due its difference in growth form. Prairie dropseed, another warm-season grass, is harmed because it initiates growth nearly as early as the cool-season species despite its warm-season physiology. On most upland old growth prairie, late spring burning favors a subset of native grasses that was not historically so abundant.  

The effect of fire exclusion on composition can be similar to those of frequent late spring burning. Species with elongating rhizomes are better able to emerge through excessive accumulations of thatch. Hensel (1923)11 observed this 100 years ago in the Kansas Flint Hills. Little bluestem increased with annual early spring burning, but big bluestem replaced little bluestem atop the dominance hierarchy when fire was excluded. Weaver and Rowland (1952)12 also observed this in eastern Nebraska in the absence of burning, haying, or grazing: 

“Consequences of the effects of the mulch upon the environment were production of a nearly pure, but somewhat thinner than normal, stand of Andropogon [big bluestem]. The understory of upland prairie had all but disappeared. The usual mid grasses of upland were few or none. Only a few taller forbs remained.”—Page 19 

Burning in the presence of excessive litter accumulation, which often occurs on prairies that are occasionally burned (as opposed to frequentyly)kill or weaken little bluestem13 and other bunchgrasses (e.g., needlelegrass)14. Their buds are at or just above the soil surface and vulnerable to increased fire duration when excessive litter has built up. This is not the case for the deeply buried buds along the rhizomes of big bluestem or Indiangrass. Interestingly, excessive litter may interact with fire to affect prairie bunchgrasses and certain invertebrates (skippers: Hesperia ottoe and H. Dakotae)15 in similar ways, with responses contingent on the amount of litter accumulation!  

Native bunchgrasses decrease for many of the same reasons in response to confined grazing. Porcupine grass is very palatable and emerges before most other prairie grasses, so it disappears quickly upon pasturage16. The long-rhizomatous prairie grasses also decrease in response to grazing16, but they persist and recover relatively well during rest periods because they have greater reserves of belowground buds available for recovery and their elongating rhizomes help them colonize openings where vegetation has been thinned by disturbance. The position of buds on these long-rhizomatous grasses an inch or two beneath the soil surface also protects their regenerative capacity from mechanical disturbance 10,17. Weaver recognized the importance of rhizomatous habit for recovery from disturbance, but not bud depth or number. Nonetheless, where grazing was too intense and prolonged, most prairie grasses were replaced by long-rhizomatous, cool-season species like Kentucky bluegrass (Poa pratensis), except on the driest sites1,2,16. 

The work of Weaver, Curtis, Hayden, and others adds important context to our interpretation of more contemporary studies of prairie. They help us discern between research and management outcomes from altered grasslands that no longer retain old growth composition, and prairies that still do. Porcupine grass, little bluestem, prairie dropseed, side-oats grama, and/or Leiberg’s panic grass are usually among the prominent grass species on the best remaining old growth, upland prairies. All of those species differ from big bluestem in their ecologies in ways that have implications for management. Except side-oats grama, many of those differences stem from growth form, cool-season physiology, or both. Earlier work on composition also highlights the amazing persistence of well-stewarded and less historically exploited old-growth prairies in the face of unprecedented change. Upland old-growth prairies that retain much of their composition have typically experienced: 

  • fewer periods of excessive litter accumulation. 
  • fewer late spring burns and more burns between fall and early spring—the more frequent the better9,18,19. True prairie composition was and is an expression of dormant season fire.  
  • minimal fenced grazing. Free-roaming deer, elk, bison, and their predators/hunters are separate issues.  
  • less fragmentation19, but consider that small, less exploited prairies that are well-stewarded retain more of their historical botanical composition than landscape grasslands in the western tallgrass region. Little prairies are more vulnerable to neglect, which argues for their protection and care.  

While the confluence of these conditions is tragically rare, the persistence of what remains is reason to keep hope. True prairie in the Midwest has been home to members of east-west and north-south expanding and contracting flora, fauna, and cultures for millennia. Even an island of old-growth prairie carries with it immeasurable ecological memory. We can kindle that and facilitate its recovery through stewardship and by building connections among prairie places and prairie people…especially if we can get our hands on more porcupine grass and Leiberg’s panic-grass! 

References:

1 Curtis, J. 1959. The vegetation of Wisconsin University of Wisconsin Press. Madison, WI. 

2 Hayden, A. 1919. Notes on the floristic features of a prairie province in central Iowa. Proceedings of the Iowa Academy of Science 25: 369-389. 

3 Brotherson, J. 1969. Species composition, distribution, and phytosociology of Kalsow Prairie, a mesic tall-grass prairie in Iowa. Dissertation, Iowa State University.  

4 Kennedy, R. 1969. An analysis of tall-grass prairie vegetation relative to slope position, Sheeder Prairie. M.S. Thesis, Iowa State University.  

5 Glenn-Lewin, D. 1976. The vegetation of Stinson Prairie, Kossuth County, Iowa. Proceedings of the Iowa Academy of Science 83: 88-93. 

6 Dziadyk, B. and G. Clambey. 1980. Floristic composition of western Minnesota tallgrass prairie. Proceedings of the Seventh North American Prairie Conference: 45-54. 

7 Weaver, J., and F. Clements. 1938. Plant ecology. McGraw-Hill Book Company, Inc. New York and London. 

8 Weaver, J., and A. Aldous. 1935. Role of fire in pasture management. Ecology 16:651–654. 

9 Towne, G., and C. Owensby. 1984. Long-term effects of annual burning at different dates in ungrazed Kansas tallgrass prairie. Journal of Range Management 37: 392-397. 

10 10 Ott, J., Klimešová, J., and D. Hartnett. 2019, The ecology and significance of below-ground bud banks in plants. Annals of Botany 123: 1099-1118. 

11 Hensel, R. 1923. Recent studies of the effect of burning on grassland vegetation. Ecology 4: 183-188. 

12 Weaver, J. and N. Rowland. Effects of excessive natural mulch on development, yield, and structure of native grassland. Botanical Gazette 114: 1-19. 

13 Gagnon, P., K. Harms, K., Platt, W., Passmore, H., and J. Myers. 2012. Small-scale variation in fuel loads differently affects two co-dominant bunchgrasses in a species-rich pine savanna. PLoS ONE 7: e29674. 

14 Haile, K. 2011. Fuel load and heat effects on northern mixed prairie and four prominent rangeland graminoids. Thesis, Montana State University-Bozeman. 

15 Dana R. 1991. Conservation management of the prairie skippers Hesperia dacotae and Hesperia ottoe. Minnesota Agricultural Experiment Station Bulletin 594, University of Minnesota. 

16 Weaver, J. 1954. North American prairie. Johnsen Publishing Company. Lincoln, NE. 

17 Klimešová J, and L. Klimeš. 2007. Bud banks and their role in vegetative regeneration – a literature review and proposal for simple classification and assessment. Perspectives in Plant Ecology, Evolution and Systematics 8: 115–129. 

18 Bowles, M. and M. Jones. 2013 Repeated burning of eastern tallgrass prairie increases richness and diversity, stabilizing late successional vegetation. Ecological Applications 23: 464-478  

19 Alstad, A., Damschen, E., Givnish, T., Harrington, J., Leach, M. and D. Rogers. The pace of plant community change is accelerating in remnant prairies. Science Advances. 2: e1500975  

Read more about Dan Carter’s work through our blog post: 2020 Landowner Services Update