This is the second installment in a series of posts on the history of prairie restoration in the upper-midwestern United States. New episodes will appear in this space over the next few months.
Last week’s first chapter began the story of one of the earliest prairie restoration projects–at the University of Wisconsin-Madison Arboretum and the work of Ted Sperry, and Norman Fassett, the many other people who started the project and did the pioneering work. This chapter deals with the early implementation of the project that would become Curtis Prairie and carries up through current implementation and management plans. The early implementation led to experimentation in best management techniques, and the prairie planting process generated a series of theoretical and practical questions about prairie restoration that continue to guide modern day restoration work throughout the Mid West.
Professor Fassett, who supervised the first year’s plantings in what was to become Curtis Prairie used as his reference systems the remnant patches of native prairie in Dane County in southwestern Wisconsin, and remnants on the high bluffs in the western part of the state along the Mississippi River. These native prairie remnants also served as source materials (seeds, sods, and transplants) for the early plantings. The team chose sites that were slated for destruction because of highway and building construction, or farmland expansion.
Besides his legacy of guiding the initial work in the first-ever prairie restoration, Sperry, who died in 1996, left behind a rich and detailed record of his work, including observations, planting records, and analysis of the results. In notebook after notebook, in tight script and precise prose, he notes where and when each species was collected—seed, sod, or plant—and where, when, and how it was planted. We know the weather on the planting day, if the species was watered, and a general estimation of its survival rate by the end of the planting season. He also left supplemental accounts of the operation of the nursery, special experiments, and photography; the labor costs; along with observations of species growth and survival, plus field maps.
Historically, neither the Arboretum project in general, nor the Curtis Prairie in particular, was set up as a grand experiment mainly because no one knew enough at the time about restoration or prairie ecology and all the variables involved in conducting a rigorous experiment (Cottam 1987).
Nonetheless, experimentation was involved. As Grant Cottam, a student of Curtis, and who had a renowned faculty career at the University, and a long involvement at the Arboretum pointed out:
“Although the primary purpose for the establishment of the Arboretum prairies was to have samples of prairie for teaching and research, it was expected that the process of establishing the prairies would point up areas where research was needed; this did indeed turn out to be the case.” (Cottam, 1987, p. 261)
Early efforts to get the prairie started in Madison focused on finding the best planting method and researchers experimented with various planting techniques, including removing surface soil, plowing, seeding, transplanting sod, and mulching with prairie hay to transform the horse pasture into prairie. Instead of adopting a pure trial-and-error approach for the Arboretum project, Leopold, Fassett, and Sperry made sure that every step in the initial prairie restoration project was turned into a research project. For example, Fassett encouraged his graduate student John Thompson to begin experimenting with methods of establishing prairie. For example, Fassett and Thompson set up small experimental plots for the first major plantings of 42 species. The early work by Fassett, Thompson, and Sperry set the tone for later work and Dave Archibald carried out additional plantings and experimentation between 1950 and 1957. Experiments carried out in the late 1940s by Max Partch and John Curtis showed that burning favored prairie species. This finding led to the first management prescribed burn in 1950.
This research and experimentation led to an early decision about the best way to continue to establish the prairie. Curtis judged that although transplanting prairie sod dug from nearby remnants—something we would not likely do today—was the most effective, it was too expensive and too labor intensive for the large scale they had in mind for the Arboretum (Howell and Stearns, 1993, page 61.)
Curtis determined that seeding was more affordable. Curtis, and Henry C. Greene—who was single-handedly planting another Arboretum prairie a mile or so away—began experiments on the germination requirements of seed of prairie plants. They discovered that most prairie species required cold stratification for germination ( Greene and Curtis, 1950.)
Questions Generated by the Restoration Process
Kline & Howell, (1987) observed that prairies are especially suitable for certain kinds of research and for answering certain kinds of questions suggested as a result of experience with tall grass restoration in southern Wisconsin. The Kline and Howell list of questions includes:
Why are certain prairie species under-represented?
What explains the presence and abundance of exotic herbs?
Why do woody species invade prairies and how may they be controlled?
They also felt that questions of long-term community dynamics (such as disturbances, population explosions, local ecotypes, and changes in forb frequencies) could be examined during the prairie restoration process
Below are some of the many examples of knowledge and innovation generated through the act of trying to restore the prairie at the Madison Arboretum. For example:
Prescribed Management Fire.
Difficulty in establishing seedlings and in discouraging bluegrass led John Curtis to study the problem and search for solutions. In the 1940’s Curtis & Partch, (1948) conducted a series of studies of fire effects on prairie species and the plant community itself. Their research established that prescribed management fires of prairies are an essential ingredient to their restoration and continued health. (Arboretum by Howell & Stearns, 1993, page 62)
Allelopathy in Helianthus laetiflorus
Prairie restoration at the Arboretum led Curtis and Cottam, (1950) to notice that extensive patches of native sunflower both excluded other species and that the patches, while viable on the perimeter, were hollowed out in the center. Their research on this observation demonstrated that native sunflower was both allelopathic and autotoxic,
Methods of Control for Sweet Clover and control of smooth sumac
Virginia Kline (1985) Arboretum ecologist at the time conducted a series of fire studies which demonstrated that the Arboretum’s every-other-year prescribed fire schedule promoted—rather than discouraged—the continuation of the pest species white and yellow sweet clover (Meliotus alba and M. officinalis). Based upon the study’s recommendations the Arboretum fire crews began to use an early spring burn one year to stimulate synchronous germination of sweet clover seeds followed by a late spring burn the following year to kill developing second-year sweet clover plants. Using this burn strategy, sweet clovers were eventually eliminated from the Arboretum prairies.
The process of recreating a prairie also demonstrated the lack of knowledge of the species composition of prairies, how they functioned, and the variety of prairie community types. This knowledge gap inspired John T. Curtis and his students at the University of Wisconsin to conduct a multi-year study of remnant plant communities that resulted in the groundbreaking “The Vegetation of Wisconsin” by J.T. Curtis in 1959.
Community Dynamics on Prairie
The planting of Curtis and Greene Prairies provided a wonderful opportunity to observe the ways in which the composition of prairies changed over time. (Sperry, 1984; Cottam & Wilson, 1966.)
Cottam (1987, pages 268-270 ) while he agrees with Howell & Kline that prairie restoration can answer some questions about basic ecological processes, he goes further to argue that “setting up a restoration to answer specific hypotheses, however, presents many difficulties.” He concludes: “Given our present knowledge, any grand plan of starting a restoration with the expectation of achieving answers to specific, basic ecological questions is likely to result in disappointment and be a waste of time.”
Cottam (1987, page 265) states that “Introduction of plants in prairie restoration at UW Arboretum set the stage for a long-term study of movement of species within the developing community.” Based upon five surveys of Curtis and Greene Prairies between 1952 and 1976, Blewett (1981) performed an “exhaustive analysis”. Cottam (1987) summarized the two major finding of Blewett’s analysis in this way:
“ Two characteristics are important: the first is that a certain amount of shifting in the distribution of community types does occur during the 25 years between the first and second, as introduced species find their way to optimum sites; the second is that there is also a great deal of shifting that cannot be accounted for in this way. In fact, the various communities do not have static borders, but appear to change their location with every survey in an amoeba-like movement that seems to be a response to the short-term climatic events of the years immediately preceding the survey.”
Ted Sperry apparently conducted the first monitoring survey of the original plantings (which were just a portion of the present-day Curtis Prairie.) His initial work at Curtis Prairie ended in 1941 when the CCC camp was closed, but he made three return trips—1946, 1982, and 1990—to evaluate the success of the project. In 1984, he published the following account of the prairie’s progress:
The Curtis Prairie of the Arboretum, initiated between 1936 and 1941, originally consisted of 46 species separately planted in 237 plantings. Forty-six percent of the plantings were successful and 38 percent unsuccessful. Nine common successful species spread widely over the prairie while 9 others persisted well, but with little or no spread between 1941 and 1982. These latter are called documentary species since they precisely pinpointed their planting locations for the 1982 re-survey. From these key locations, all 237 planting areas could be determined within a meter or two. The plant persistence and succession in each of these plantings could thus be accurately documented after the 40-year interval. Some spreading species were also documentary. Starting with old farmland, this prairie has been spectacularly successful. It has been designated by the Arboretum as “the world’s oldest restored prairie.” (1984, 140)
Curtis, who as a faculty member became director of research at the Arboretum, supplemented Sperry’s vegetation surveys when he initiated the first formal vegetation surveys of the entire prairie in 1951 and 1956. He established a 16.8 x 16.8 m (50 x 50 ft) grid and recorded species presence in randomly located 1-m2 quadrats, one per grid cell. There are over 1,000 quadrats in all. 3-fttall metal posts that are now GPS located mark the grid. These vegetation surveys were conducted every 5 years until 1976, and were resumed in 2002 and 2008. (For a recent summary of the results of the 2002 survey, see Looking to the Future: Curtis Prairie, below.)
In 1951, John T. Curtis wrote the first master plan for the Arboretum, which established the general layout of plant communities you can see today. In 1992, then Arboretum Ecologist Dr. Virginia Kline wrote an updated version of the Curtis plan, entitled “The Long-Range Management Plan for Arboretum Ecological Communities” (Kline 1992). The Kline Plan, as the Long Range Plan has come to be known, was intended to review the status of the Arboretum’s then several different restorations, and to recommend what implementation or management steps were still needed. In addition, it reviewed and updated the original Arboretum vision to reflect the evolution of the use-policy since 1951.
The 1992 plan is essentially a master plan in that it establishes the use-policies for research, management, and visitors, and, as was the case with the original Curtis plan, lays out the boundaries of the different communities. The Kline Plan does not include a detailed overall site plan, implementation plan, management plan, or monitoring plan.
Current research takes advantage of grant opportunities, management problems, and faculty and graduate student research interests, and it relies upon an adaptive restoration framework. Ongoing studies focus on linking research and land care by developing adaptive management solutions to urban restoration challenges, such as storm water runoff and invasive species management.
Conclusion and summary. An assessment of the accomplishments and contributions of the Arboretum to restoration and some of the constraints it has faced.
Blewett, T. 1981. An ordination study of plant species ecology in the Arboretum prairies. Wisconsin: University of Wisconsin PhD thesis.
Blewett, T. and G. Cottam. 1984. “History of the University of Wisconsin Arboretum Prairies.” Transactions of the Wisconsin Academy of Sciences, Arts, and Letters 72:130-144.
Cottam, G. 1987 “Community Dynamics on an Artificial Prairie.” In Restoration Ecology: A Synthetic Approach to Ecological Research, edited by W. R. Jordan, 257-270. New York: Cambridge University Press.
Cottam, J.T. and H.C. Wilson. 1966. Community dynamics on an artificial prairie. Ecology. 47, 88-96.
Curtis, J. T. 1956. A prairie continuum in Wisconsin. Ecology. 36. 558-66.
Curtis, J. T. 1959. The Vegetation of Wisconsin: An Ordination of Plant Communities. Madison, University of Wisconsin Press.
Curtis, J.T. and G. Cottam . 1950. Antibiotic and auto toxic effects in prairie sunflower. Bulletin of the Torrey Botany Club, 77. 187-91.
Curtis, J.T. and M. L. Partch. 1948. Effect of fire on the competition between blue grass and certain prairie plants. The American Midland Naturalist, 39, 437-43.
Greene, H.C. and J. T. Curtis. 1950. Germination studies of Wisconsin prairie plants. Am. Midl. Nat. 43 (1): 186-194.
Howell. E. and F. Stearns. 1993 The Preservation, Management, and Restoration of Wisconsin Plant Communities: The Influence of John Curtis and His Students, pp. 57-66 IN John T. Curtis, Fifty Years of Wisconsin Plant Ecology, Edited by Fralish, J. S. and R. P. McIntosh, and O. L. Loucks, Wisconsin Academy of Sciences, Arts, and Letters, Madison, WI.
Kline, V.M. 1985. Response of sweet clover (Meliotus alba) and associated prairie vegetation of seven experimental burning and mowing regimes. In Proceedings of the 9th North American Prairie Conference. Ed G.K. Clambey and R. H. Pemble, pp. 149-152. Fargo: Tri-College Press.
Kline, Virginia M. 1993. John Curtis and the University of Wisconsin Arboretum, pp. 51-56 IN John T. Curtis, Fifty Years of Wisconsin Plant Ecology, Edited by Fralish, J. S. and R.P.McIntosh, and O. L. Loucks. Wisconsin Academy of Sciences, Arts, and Letters. Madison, WI.
Kline, V.M. and E.A. Howell. 1987. Prairies, pages 75-84. IN Restoration M.E.Gilpin, and J.D.Aber, editors. Cambridge University Press, Cambridge.
Kline, V. M. 1992. “The Long-Range Management Plan for Arboretum Ecological Communities.” University of Wisconsin-Madison Arboretum.
Longenecker, W. G. 1941. University of Wisconsin Arboretum. Parks & Recreation Sept.: 1-8.
McGaw, M. 2002. “The Response of Gray Dogwood (Cornus racemosa) to Prescribed Fire and the Effects of Invasion on Fuel Loading and Plant Community Composition at Curtis Prairie.” Master’s thesis. University of Wisconsin-Madison.
Peters, R. H. 1985 Global climate change: a challenge for restoration ecology. Restoration and Management Notes, 3, 62-67.
Sasche, N. D. 1974. “A Thousand Ages: The University of Wisconsin Arboretum.” Madison: Regents of the University of Wisconsin. Revised edition, originally published in 1965.
Snyder, T. A., III. 2004. “A Spatial Analysis of Grassland Species Richness in Curtis Prairie.” Master’s thesis University of Wisconsin Madison.
Sperry. T. M. 1984. Analysis of the University of Wisconsin-Madison prairie restoration project. In Proceedings of the 8th North American Prairie Conference. Ed. R. Brewer, pp140-147. Kalamazoo: Western Michigan University.
Sperry, T. M. 1990. “Report on the 1980 Curtis Prairie Survey for the University of Wisconsin-Madison Arboretum.” University of Wisconsin-Madison Arboretum.
Wegner, M. and J . Zedler. 2008. “Taking Stock: Status Report on our 75th Anniversary.” Arboretum Leaflets No. 18.
Wegner, M., P. Zedler, B. Herrick, and J. Zedler. 2008. “Curtis Prairie: 75-Year Old Restoration Research Site.” Arboretum Leaflets No. 16.