When Is a Restoration Successful? Results from a 45-Year-Old Tallgrass Prairie Restoration

by Stuart K. Allison

estoration ecology had its genesis in Knox College Green Oaks Field Study Rthe 1930s as Midwestern ecologists Center in west-central Illinois. A survey of the third came to the realization that nearly all the tallgrass prairie in Illinois, Iowa, and Green Oaks: A Pioneer Wisconsin had been converted to agricul- tural or urban land uses (Curtis and Tallgrass Prairie Restoration oldest tallgrass prairie Greene 1949, Critical Trends Assessment In November 1954, two. members of the Project 1994, Smith 1998). While calls Knox College Biology Department— for preservation of remaining prairie in George Ward and the late Paul Shepard— Iowa began by 1919 (Smith 1998), the visited the Arboretum in Madison and restoration in the pioneer restoration ecologists of the early toured its prairies. After their visit, they 20th century recognized that if extensive resolved to undertake a tallgrass prairie areas of tallgrass prairie were going to be restoration at Green Oaks (Shepard, part of our future, they would have to Green. Oaks News, Dec. 7, 1954, Knox. Midwest demonstrates begin to restore these historic grasslands. 'College Library Archives). Shepard's goal The first efforts were undertaken at for the restoration at Green Oaks was sim- the University of Wisconsin-Madison ilar to that of the prairie restorations at the Arboretum, initially as experimental plots University of Wisconsin-Madison Arbore- the difficulty under the direction of biology professor Dr. tum, namely a "complete restoration: the Norman Passett, and later under the direc- establishment of a group of species in tion of Dr. Theodore Sperry and Dr. Henry abundances and proportions similar to Greene, Dr. Sperry led the restoration those in natural communities such that of achieving a activity at Curtis Prairie—a planting effort natural processes occur" (Howell and that involved men from the Civilian Jordan 1991). Conservation Corps and lasted from 1936 Shepard and Ward began planting the through 1940—while Dr. Greene almost prairie in April 1955 with seeds of 63 "corn p lete restoration ." single-handedly planted Greene Prairie plant species that they either collected between 1943 and 1952 (Blewett and along railway rights-of-way and pioneer Cottam 1984). Their efforts served as the cemeteries or received from the University inspiration for the third tallgrass prairie of Wisconsin Arboretum (Shepard, Green restoration in the Midwest (Howell and Oaks News, April 11, 1955, Knox College Jordan, 1991) which took place at the Library Archives). The first prairie they

Ecological Restoration, Vol. 20, No. 1, 2002 ISSN 1522-4740 012002 by the Board of Regents of the University of Wisconsin System.

10 ECOLOGICAL RESTORATION 20:1 w MARCH 2002 During the 1950s George Ward (second from the left) and the late Paul Shepard (far right) were members of the Biology Department at Knox College in Galesburg, Illinois. In 1955, they planted the first section of prairie (East Prairie) at Green Oaks. Shepard left Knox College in 1963, having planted East Prairie and started another known as West Prairie. Shepard was later to become famous as the author of several provoca- tive books, including The Tender Carnivore, Subversive Sciences, Coming Home to the Pleistocene, and Nature and Madness. Also in the photo are Bill Ward (left, the property caretaker, but no relation to George Ward) and Alvah Green (second from right, a local attorney and the prop- erty owner at the time George Ward and Shepard starting planting). Photo courtesy of Stuart K. Allison planted became known as East Prairie. based his restorations on remnant prairies, they are and whether they are good copies Shepard continued and expanded the he felt it might he almost impossible to of natural prairies. prairie plantings, initiating another prairie exactly re-create original prairie so his The first step in analyzing the success restoration at West Prairie. goal became the establishment of an aes- of a restoration is to determine whether In 1963 Shepard left Knox College. thetically pleasing facsimile of original the restorationists involved set clear goals He was replaced by Peter Schramm, who prairie (Schramm 1992). Schramm com- before they proceeded with their work. A was hired in 1965. Schramm maintained pleted major plantings in West Prairie by major problem for all restorationists is the original plantings, expanded the 1973 and in South Prairie by the late that they are attempting to recreate an plantings in West Prairie, and began a 1970s. Even after those plantings were ecosystem that is no longer present on the new prairie restoration at South Prairie in finished, he continued to experiment site and is known only from historical 1966 (Schramm 1992). Schramm treated with transplanting rare prairie plants into records. Restorationists often find it diffi- the restorations in West and South established prairie in both West and cult to set definite ecological standards for Prairies as a working laboratory in which South Prairies (D. Krohne pers. comm.). such a restoration because they do not he tested different restoration techniques Now that these restored prairies are have quantitative data about the histori- and mixtures of plant species. Though he maturing, we cart ask just how successful cal condition of a site (Westman 1991).

ECOLOGICAL RESTORATION 20:1 ■ MARCH 2002 11 This was certainly the case for the prairie have been somewhat different from the are all located at Knox College's Green restorations at Green Oaks. Shepard's prairies Mead saw. Curtis and Greene Oaks Field Study Center. Green Oaks is a notes (Knox College Library Archives) (1949) felt that prairie remnants were 760-acre field station located 20 miles east indicate that his goal for the restored unlikely to be representative of natural of Galesburg in Knox County in west-cen- prairies at Green Oaks was to eventually prairie because often the remnants sur- tral Illinois. The field station is located in replicate the prairies that existed at the vived because they were on sites that were an area where oak savanna graded into time of European settlement of Knox not as conducive to agriculture as typical oak-hickory forest at the time of European County in the 1830s. Schramm continued prairie. They also thought that the small settlement. The restored prairies are all the restorations with this final goal in size of the prairie remnants and their arti- located on land that was planted with mind, although Schramm felt that, due to ficial isolation from other prairie patches crops such as soybeans and alfalfa, or used the lack of historical data, existing prairie would lead to species losses, an hypothesis as pasture, prior to restoration. They are remnants had to serve as the model for that was confirmed when Leach and relatively small, with East Prairie at 5.8 prairie restoration (Schramm 1992). Givnish (1996) resampled the prairie acres, South Prairie at 12.9 acres, and West I began this study by asking: How suc- remnants Curtis and Greene studied. Prairie at 19 acres, One of the remnant cessful are the restored prairies at Green Leach and Givnish (1996) estimated that prairies, Lost Meadow, is also located at Oaks? Because historical data are lacking prairies lose from 0.5 to 1.0 percent of Green Oaks. Lost Meadow is a small (0.9 and Schramm used remnant prairies as his their plant species per year due to fire sup- acres) prairie-savanna site that is currently model, I decided to analyze the success of pression and habitat fragmentation. surrounded by second growth oak-hickory the restorations at Green Oaks by compar- forest. We don't have a good history of Lost ing the restored prairies with nearby prairie Meadow, but it probably experienced some remnants. The best way to judge the success Methods grazing until the 1930s. After that, Lost of the prairie restorations at Green Oaks is Study Sites Meadow was allowed to lie fallow and was by comparing the restored and remnant My research was conducted at three sites— invaded by woody plant species, especially prairies in terms of the percentage of species Green Oaks Field Study Center, Brownlee smooth sumac (Rhos &bra) and blackberry present in them that also appear in Mead's Cemetery Prairie Nature Preserve, and (Rubus allegheniensis). The woody vegeta- (1846) list of prairie plants present at the Spring Grove Cemetery Prairie Nature tion was cleared by hand in the summer of time of European settlement. Mead listed a Preserve (Figure 1). The restored prairies 1972 and spring burning was initiated in total of 297 species occurring in prairies in 1973 (D. Krohne pers. comm.). All of the west-central Illinois, primarily in Hancock prairies at Green Oaks are mesic prairies County. I found 100 species in the restored that are maintained by burning in the early prairies at Green Oaks, and 72 of them (72 spring every other year. percent) were listed by Mead. I found 105 I also studied two prairie remnants species in the remnant prairies, 75 of which located close to Green Oaks (Figure 1). Brownlee (71.4 percent) were listed by Mead. The Brownlee Cemetery Prairie Nature Pre- restored and remnant prairies are about Spring serve and Spring Grove Cemetery Prairie Grove equally composed of plant species known to Nature Preserve are Illinois Nature Pre- be present in Illinois prairies at the time of serves administered by the Illinois Depart- European settlement. ment of Natural Resources. Brownlee and Using remnant prairies as the model Spring Grove are both small (1.4 acres and for determining the success of prairie 1.1 acres respectively), mesic, black soil restoration is also problematic. Remnant prairie remnants. The Brownlee Cemetery prairies are not static and are likely to was established in 1842 and the Spring have changed during the approximately Grove Cemetery was established in 1859. 170 years since European settlement. Of Neither was ever cultivated. Both ceme- course, the question we can never answer tery remnants are surrounded by agricul- is whether 72 percent of the species in the tural land and are maintained by burning remnant prairies would have occurred on sections every other year. Mead's list if they had been sampled 170 years ago.at the time Mead began compil- ing his species list. Taft (1995) feels that Figure 1. Map of Illinois showing the location Data Collection prairie remnants in Illinois have survived of the three study sites: Green Oaks Field Four times—from June through Septem- at random, captured different subsets of Study Center (Knox County), Brownlee ber 1999-1 randomly placed 25-rn belt the total prairie flora, and thus are proba- Cemetery Nature Preserve (Mercer County), transects within the prairies and then bly low in floristic similarity. So it is likely and Spring Grove Cemetery Nature Preserve identified all plant species that occurred that the prairie remnants I studied would (Warren County). within one meter of the central transect

12 ECOLOGICAL RESTORATION 20:1 • MARC:H 2002 • mean C mean C ■ FQI FQI • transect • % alien -If-% alien ■ 25 • quadrat 20 ■ ■ 25 c 20 20 -c • ce.Y 15 15

a) 10 10 c) a) CI 5 ■ 5 tr) ■ $ 0 0 West South East Lost Sp , voilee Remnant Restored Remnant Restored Prairies Prairies Prairies Figure 2. Comparison of mean species rich- Figure 3. Comparison of mean Coefficient of Figure 4. Comparison of mean Coefficient of ness in quadrats and belt transects on rem- Conservation (mean C), Floristic Quality Index Conservation (mean C), Floristic Quality Index nant and restored prairies. (FQI), and mean percent of alien species (FQI), and mean percent of alien species recorded in belt transects on remnant and recorded in belt transects on each of the restored prairies. prairies sampled. West, South, and East Prai- ries are restored, others are remnant prairies.

line. I also placed 0.10-m 2 quadrats at disturbance and is found only in original, prairies (F = 47.77; df = 1, 449; p < five-meter intervals along each transect native habitat (tall or prairie cinquefoil 0.001) (Figure 2). line. I used the quadrats to collect data on IPotentilla argutal in Illinois). My analysis also indicated that the plant abundance and ground cover by I calculated mean conservatism values mean Coefficient of Conservatism was identifying the plants occurring at 25 for each transect or quadrat sample. The significantly higher in restored prairies points on a 0.10-m2 grid. I placed five belt mean conservatism values can then he than in remnant prairies (F = 7.65; df = 1, transects in West and South Prairies, four multiplied by the square root of species 89; p = 0.007) (Figure 3). This result sur- belt transects in East Prairie, and three richness to arrive at the Floristic Quality prised me, so I decided to look more belt transects in Lost Meadow, Spring Index (FQ1), a measure that combines con- closely at the data by performing an Grove, and Brownlee Prairies. I used fewer servatism with number of species in a sam- ANOVA that examined mean conser- transects in the smaller prairies because I ple. I calculated mean conservatism and vatism on a per prairie basis. I found that did not want to over-sample the small FQI both with and without alien species the mean conservatism was significantly prairies. Using this method, I was able to and obtained the same result for both met- different among the prairies (F = 10.6; df observe almost the entire sequence of rics regardless of whether I included alien = 5, 89; p < 0.001). A Tukey's multiple flowering phenology of these prairies. species or not. In this paper all mean con- comparison test revealed that Brownlee, servatism and FQI scores that I report have West, and South Prairies had significantly been calculated exclusive of alien species. higher mean conservatism (Figure 4), and Data Analysis I used Minitab for Windows, version thus contain more plant species typical of 1 compared the restored and remnant 12.1, for all statistical analyses. I compared undisturbed, original prairie than do Lost prairies by examining species richness the type of prairie (restored or remnant) or Meadow, Spring Grove, and East Prairies. ( the number of species) that occurred in individual prairies using ANOVA followed found no significant difference in the transects and quadrats. I also made by Tukey's multiple comparison test. FQI between the two types of prairie, comparisons using the Coefficient of restored and remnant (F = 1.17; df = 1, Conservatism (Taft and others 1997) a 89; p = 0.283) (Figure 3). 1 was also sur- system of analysis that describes and Results prised by this result because I had quantifies the tendency of a plant species I found a total of 134 plant species in the expected the remnant prairies to have to he resistant to disturbance and the prairies, but the species were not evenly greater FQI than the restored prairies. fidelity of that species to undisturbed, distributed among the prairies (Table I). However, FQI was significantly different original native habitat. The Coefficient of Species richness was significantly greater among the individual prairies (F = 5.99; df Conservatism is scored using an 11-point along transects in remnant prairies when = 5, 89; p < 0.001). Brownlee Prairie had scale with a score of zero indicating the compared to transects through restored a significantly higher FQI than did any of plant is weedy and found in any habitat prairies (F = 18.35; df = 1, 89; p < 0.001) the other prairies indicating that Brown-. (common millkweed Vsdepias syriacal is a (Figure 2). Species richness as measured lee possessed both a higher number of good example in Illinois) and a score of in quadrats was also significantly higher species and more conservative species ten indicating the plant is susceptible to in remnant prairies than in restored than any of the other prairies (Figure 4).

ECOLOGICAL RESTORATION 20:1 ■ MAIu ii 2002 13

Table 1. List of plant species found in the restored and remnant prairies during this study. An X indicates that a plant species is found in a particular prairie. Coefficient of Conservatism (C.C.) is taken from Taft and others 1997. An asterisk by a species name indicates that species is one listed as planted at Green Oaks by Schramm (1992). Nomenclature based on Mohlenbrock 1986.

Latin Name Common Name C.C. West South East Lost Spring Brownlee Latin Name Common Name C.C. West South East Lost Spring Brownlee Achillea millifolium common yarrow 0 - alien X X X Euthamia graminifolia lance-leaved 3 X X goldenrod Alopecurus caro/inianus foxtail 0 X Fragaria virgin iana wild strawberry 2 X Ambrosia arternisifolia common ragweed 0 X X X X Gentiana andrews ii bottle gentian 7 Ambrosia Hilda giant ragweed 0 X X creamy soapwort 9 X X "Arnorpha canescens leadplant 8 X X Gentiana saponaria gentian *Andropogon gerardit big bluestern 5 X X X X X X Glycena strata fowl manna grass 4 X Apocynum spreading dogbane 6 x X androsaemifolium Helianthus divaricatus woodland sunflower 5 9 X X X X X Apocynum cannabinum dogbane 2 X X X X X Helianthus giganteus tall sunflower X X X X X Asciepias purpurascens purple milkweed 7 X X X Helianthus grosseserratussawtooth sunflower 2 XX X X Asclepias syriaca common milkweed 0 X X XX X X Helianthus hirsutus stiff-haired sunflower 5 X X X *Ascleplas tuberosa butterfly milkweed 5 X X Helianthus mollis hairy sunflower 7 X X Aster simplex parucled aster 3 X X XX X X Helianthus tuberosus Jerusalem artichoke 3 Astragalus canadensis Canada milk vetch 7 X X Heliopsis helianthoides oxeye 4 X *Baptisia lac-tea white wild indigo 6 X X X X X Hypericum perforatum common 0 - alien X X X St. John's wort &dens frondosa beggarticks 1 X Hypericum pyramiciatum great St. John's wort X X Bidens spp. sticktight X ipomoea pandurata wild potato vine 2 X Bromus inermis smooth brome 0 - alien X X X Juncus interior inland rush 3 X X XX X Calystegia septum hedge bindweed 1 X X Lactuca canadensis wild lettuce '1 X X X Campanula americana tall bellflower 4 X 'Lespedeza capitata round-headed 4 X X XX X X Carex bicknelli Bicknell's sedge 8 X X XX X X bush clover Castelleja coccinea Indian paintbrush 8 X 'Lams pycnostachya prairie blazing star 6 X X Ceanothus americana New Jersey tea 8 X X Liatris spp. blazing star X X X X X Cirsium discolor pasture thistle 3 X Lobelia inflate Indian tobacco 4 X Cirsium pumifum prairie thistle 7 X X X X Lobelia spicata pale spike lobelia 4 X X Cirsium vulgare bull thistle 0 - alien X X X Lysimacha quadnfolia whorled loosestrife 9 X Cleome hassleriana spiderflower 0 - alien X X Melilotus alba white sweet clover 0 - alien X X X Convolvulus arvensis field bindweed 0- alien X X X X Melilotus sp. sweet clover 0- alien X X X X *Coreopsis palmata stiff-leaved coreopsis 6 X X X *Monarda flstulosa wild bergamot 4 X X X X X X Coreopsis tripteris tall coreopsis 4 X X X Mores rubra red mulberry 4 X Coronilla va ria crown vetch 0 - alien X X Muhlenbergia mexicana leafy satin grass 4 X Cuscuta compacta compact dodder 10 X Muhlenbergia sp. mehly grass X Dactylis glomerata orchard grass 0 - alien X Nepeta cataria catnip 0 - alien *Dalea candida white prairie clover 9 X X X Oenothera biennis common evening 1 X *Dalea purpurea purple prairie clover B primrose *Desmodium canadense showy tick trefoil 5 X X X X Par cum kneegrass Desmodium canescens hoary tick trefoil 4 X X X X X dichotomiflorum Desmodium glutinosum pointed-leaved 3 'Panicurn virgatum switchgrass 4 X XXX X X tick trefoil 'Parthenium wild quinine 8 X X *Desmodium iilinoense Illinois tick trefoil 5 X X X integrifolium Dracocephalum American 0 - alien X Pastinaca sativa wild parsnip 0 - alien X X parviflorum dragonhead *Penstemon digitalis foxglove 4 X *Echinacea pallida pale purple 7 X X X X X beardstongue coneflower Phalaris arundiancea reed canary grass 0 - alien X Elymus canadensis Canada wild rye 4 X X X X Phleuin praterse timothy 0 - alien X Equisetum arvense horsetail 0 X X Plantago ianecofata English plantain 0 - alien X Equisetum hymale scouring rush 2 X Polygonatum Solomon's seal 4 X Erigeron annus daisy fleabane 1 X X X X X commutatum *Eryngium yuccifolrum rattlesnake master 7 X X X X X Polygonum Pennsylvania 1 X Eupatorium serotinum late-flowering 1 X pensylvarucum srnartweed throughwort Polygonum scandeus climbing false 2 X Euphorbia carol/ea flowering spurge 3 X XX X X buckwheat

14 ECOLOGICAL RESTORATION 20:1 ■ MARCH 2002 Latin Name Common Name C.C. West South East Lost Spring Brownlee Because the results of comparisons examining mean Coeffi- "Potentifla arguta tall cinquefoil 10 X X cient of Conservatism and FQI surprised me, I decided to test Potentilla simplex common cinquefoil 3 whether the two types of prairie differed in the percentage of alien Prunus serotina wild cherry 1 X X species present among all species along the transects. There was no "Pycnanthemum narrow-leaved 4 X X X X X X significant difference in percentage of alien species between tenuifoliurn mountain mint restored and remnant prairies (F = 2.23; df = 1, 89; p = 0.139) Quercus macrocarpa bur oak 5 x (Figure 3). Individual prairies differed significantly in terms of per- Quercus spp. oak X centage of alien species (F = 4.74; df = 5, 89; p = 0.001) with *Re tibida pinnata gray-headed 4 X X X X Spring Grove Prairie having significantly-more alien species than coneflower West, South, and Lost Meadow Prairies (Figure 4). Brownlee and Rhus glabra smooth sumac 1 X XX X X East Prairies were intermediate in the percentage of alien species Robinia pseudoacac a black locust 0 - alien and did not differ significantly from any other prairies. Rosa carolina pasture rose 4 X Rubus allegheniensis blackberry 2 X X XX X x "Rudbeckia hirta black-eyed susan 2 X X XX X Discussion Rudbeckia lacinata green-headed 3 X X X I expected to find that the remnant prairies would have higher coneflower species richness, mean plant conservatism, and floristic quality Rudbeckia subtomerrtosa sweet coneflower 5 indices than the restored prairies. While it is clear from the Rueliia humifis hairy rude 3 X results that the restored prairies are different from the remnant Rumex crispus curly dock 0 - alien prairies, those differences did not always match my initial expec- •Schizachyrium scoparius little bluestem 5 X X XX X X tations. I suspect that the differences are probably due to the his- Scirpus atrovirens dark green rush 4 X tory of the remnants and the method of planting the restored Scirpus hattatonanus early dark 5 X prairies (Table 2). The restored prairies, for example, have rela- green rush tively high mean conservatism and FQI because Shepard and *Siiphiurn integrifofum rosinweed 5 X X X X X Schramm chose to plant species typical of high quality native *5ilphiurn laciniatum compass plant 5 X X X X X prairies (Schramm 1992). Meanwhile the remnant prairies cl ilfer *Silphium prairie dock 4 X XX in their past history. Brownlee Cemetery Prairie and Spring terebinthinaceum Grove Cemetery Prairie were protected from human disturbance Solidago altfssima tall goldenrod 1 X X XX X X in the mid-1800s, while Lost Meadow has experienced various Solidago canadensis Canada goldenrod types of land use and management. All of the remnant prairies, Solidago gigantea late goldenrod 3 X X X X X and especially Lost Meadow and Spring Grove, have many Solidago juncea early goldenrod 4 X X X weedy or disturbance-resistant native species. Brownlee and 'Solidago rigida stiff goldenrod 4 X X Spring Grove, which are surrounded by agricultural land, have 'Solidago speciosa showy goldenrod 7 X X several alien species as well. Thus it seems that the small, isolated *Sorghastrum nutans Indian grass 4 X X x X prairie remnants have been subject to invasion by alien species Sphenopho/is obtusata slender wedge grass 5 X X XX and weedy natives or else those species are well suited for long- var. major term survival in the remnants. The restored prairies, which were Stachys aspera hyssop-leaved 9 X established using conservative native prairie plants, have rela- hedge nettle tively fewer of the weedy, invasive species (Table 1). 5tachys tenuifolia rough hedge nettle 5 X X One of the most striking differences between the restored var. hispida and remnant prairies is the tendency of the restored prairies to 7eucrium canadense germander 3 X have a patchy distribution of species, with plants often grouped Thalictrum diolcurn early meadowrue 5 X into a mosaic of single-species patches. In contrast, plant species Thalictrum revolutum waxy meadowrue 5 X in the remnants occur in a more highly intermingled distribution Toxicodendron radicans poison ivy 1 with several species occupying a small area. This was most clearly 'Tradescantia ohiensis spiderwort 3 X X XX X X shown in the comparison of species richness in quadrats, where, Ulmus rubra slippery elm 3 X X X X even at the small scale of 0.10 mz, the remnant prairies had sig- Ulmus thomasii rock elm 3 nificantly greater species richness than did the restored prairies Verbena hastata blue vervain 3 X (Figure 2). This patchy distribution pattern of plants in prairie Verbena urticifolia white vervain 3 X restorations has been observed in other restorations, including Vemonia arkansane Ozark ironweed 10 X the Curtis and Greene prairies (Cottam and Wilson 1966, Vemonia gigantea tall ironweed 4 X X XX X X Blewett and Corwin 1984). The patchy distribution is almost "Veronicastrurn Culver's root 6 X X X certainly the result of the original pattern of planting the restora- virginicum tion. Schramm (1992) advocates planting in a mosaic pattern Vitis spp. wild grape X X and notes that "what you plant is what you get." The question

ECOLOGICAL RESTORATION 20:1 • MARCH 2002 15 then arises: For how many years will the Table 2. A comparison of species richness, number of alien species, mean original planting pattern determine the Coefficient of Conservatism, and Floristic Quality Index (FQI) calculated based on distribution of plants in a restored prairie? all the samples collected in each prairie. The answer is apparently for many years. Prairie Name Type of Prairie Species Number of Mean FQI When Sperry resampled Curtis Prairie in Richness Alien Species Conservatism 1990 (54 years after the initial planting), Brownlee Remnant 76 11 4.22 34.02 he could still find patches dominated by Lost Meadow Remnant 50 2 3.89 26.99 the species first planted at that location Spring Grove Remnant 54 9 3.69 24.74 (Sperry 1994). East Restored 63 11 4.23 30.51 South Restored 69 9 4.65 36.02 West Restored 64 6 4.29 32.69 Problems in Judging Restoration Success Several problems arise when restorationists 63 prairie species in 1955 (Shepard, Green relative abundances and interactions of attempt to determine the success of prairie Ociks News, April 11, 1955, Knox College those species. Remnant prairies have restoration projects. Some problems are Library Archives), but there is no record changed in the last 170 years and it is unique to a site, such as Green Oaks, but of the identity of those 63 species. I have likely that the original prairies would others are more general and probably apply searched the Knox College Library have changed in that time, even without to all prairie restorations. I will consider Archives several times and have never the influence of settlers and modem agri- those unique to Green Oaks first and then been able to find a written list of what was culture (Howell and Jordan 1991). Thus discuss more general problems. planted that spring. Schramm (1992) pro- we have chosen an extremely daunting One of the most difficult aspects of vides a list of 48 species he planted during task if our goal in restoring prairies is to judging the success of prairie restoration prairie restoration at Green Oaks. I found achieve grassland ecosystems that are sim- 30 of those species (marked with an aster- ilar to original native prairies in structure isk in the species list in Table 1) during and function. However, if our goal in my sampling. The remaining 18 species prairie restoration is to develop self-sus- A major problem for that Schramm planted either have died taining prairies that support native prairie out or are rare enough that I missed them flora and fauna, then we probably can all restorationists is during sampling. achieve success. And in doing so, we will The small size of both restored be restoring an ecosystem to our land- that they are attempting prairies and remnant prairies points to scape that would otherwise continue to the problem of scale (Noss 1992). The dwindle away. to re-create an pre-European settlement prairies were large, continuous ecosystems. Remnant ecosystem that is no and restored prairies usually exist as small Conclusions islands that are isolated from other such At this time, the prairie restorations at longer present on the islands and surrounded by dissimilar habi- Green Oaks have not been successful in tat. They are vulnerable to invasion from achieving the planners' original goal of re- site and is known only species typical of other ecosystems, often creating pre-settlement tallgrass prairie. forest species and weedy alien species. Ultimately, it seems unlikely that such a from historical records. Their small size means they experience a goal can he achieved because the restored different physical environment than did prairies are dynamic and constantly the original prairies and this may have changing. Schramm (pers. comm.) reports at Green Oaks is that the planting records considerable effect on their ecology that some plant species in the restored for the Green Oaks restorations are rather (Janzen 1986). For example prairies bor- prairies at Green Oaks change their loca- poor. This is especially obvious when one dered by woodlands are more subject to tions from year to year. He says this is compares the meticulous records of plant- shading and are somewhat buffered from especially true of a species such as hairy ing history that exist for the Curtis and winds (Kline and Howell 1987). sunflower (1-ielianthus mollis), which is Greene prairies to the scanty records for In the end, remnant prairies and pre- allelopathic and tends to kill nearby com- Green Oaks. Without good records, it is settlement species lists provide us with peting plants. Given the fact that some difficult to determine whether the plants clues about original native prairie but we plant species move around the prairie, it is in the restored prairies are the result of the will never know exactly what those surprising that the restored prairies still original plantings or whether the species prairies were like. We will never know the retain a mosaic distribution of species have colonized on their own. We know identity of all the species present in origi- when compared to the intermingled pat- that Shepard and Ward planted seeds of nal prairies and we will never know the tern of species distribution in remnant

16 ECOLOGICAL RESTORATION 20:1 ■ MARCH 2002 prairies. It may he that it will take many Cemetery Nature Preserve and the Spring Mead, S.R. 1846. Catalogue of plants growing. years of such plant movements before the Grove Cemetery Nature Preserve. Sharon spontaneously in the state of Illinois, the Clayton, my reference librarian, was extremely principal parr near Augusta, Hancock original planting pattern is broken and a helpful as I gathered references. David Krohne County. The Prairie Farmer 6:35-36, 60, 93, more natural and intermingled species and Frank McAndrew read an early draft of 119-122. distribution arises. this paper. Their comments helped me Mohlenbrock, R. 1986. The illustrated flora of We also must not forget that restora- improve the paper. An anonymous reviewer Illinois. Carbondale, IL: Southern Illinois tion goals have to be set in terms of gave me many excellent ideas that I used to University Press. further improve the paper. Noss, R. 1992. Issues of scale in conservation human values as well as ecology (West- biology. Pages 239-250 in P.L. Fiedler and man 1991). Although the prairie restora- S.K. Jain (eds.), Conservation biology: The tions at Green Oaks have not met the REFERENCES theory and practice of nature conservation, original ecological goal of re-creating Blewett, T.J. and G. Cottam. 1984. History preservation, and management. New York: original prairie, the Knox College com- of the University of Wisconsin A rbi irer Lim Chapman and Hall. Wisconsin Schramm, P. 1992. Prairie restoration: A munity tends to regard the prairies as a prairies. Transactions of the Academy of Sciences. Arts, and Letters twenty-fiye year perspective Lin establish- great success. The prairies are attractive 72:130-144. ment and management. Pages 169-177 in and provide at least a small-scale sensory Calkins, E.E. 1989. They broke the prairie. D.D. Smith and C.A. Jacobs (eds.), Pro- experience of pre-settlement prairies. Urbana: University of Illinois Press. ceedings of the twelfth North American Every year many members of the campus Cottam, 0. and H.C. Wilson. 1966. Com - prairie conference: Recapturing a vanish- ing heritage. Cedar Falls: University of community take part in burning the munity dynamics on an artificial prairie. Ecology 47:88.96, Northern Iowa Press. prairies at Green Oaks and for many of Critical Trends Assessment: Project. 1994. The Smith, D.D. 1998. Iowa prairie: Original them the prairie fires are one of the high changing Illinois environment: Critical extent and lass, preservation, and recovery points of the year. The nickname for the trends—A summary report of the Critical attempts. Journal of the Iowa Academy of athletic teams at Knox is the Prairie Fire, Trends Assessment Project. Illinois Depart- Sciences 105:94-108. Sperry, T.M. 1994. The Curtis Prairie restora- and many memhers of the community ment of Energy and Natural Resources and Nature of Illinois Foundation. Springfield, tion, using the single-species planting take great pride in the heritage of a col- Illinois. method. Natural Areas Journal 14: t 24-127. lege established on the prairie (Calkins Curtis, J.T. and H.C. Greene. 1949. A study of Taft, J.B. 1995. Ecology, distribution, and 1989). While our restored prairies may relic Wisconsin prairies by the species-pres- rareness patterns of threatened and endan- not exactly match the original prairie, ence method. Ecology 30:83-92. gered prairie plants in Illinois. Pages 21-31 in T.E. Rice (ed.), Proceedings of the fourth they do provide a model of the original Howell, E.A. and W.R. Jordan Ill. 1991. Tall- grass prairie restoration in the North central &pie, prairie conference. Decatur, landscape—a model that is valuable if American Midwest. Pages 395 ,414 in LE Illinois: Milliken University. only because these sites are pleasing to the Spellerberg, F.B. Goldsmith and M.G. Taft, J.B., G.S. Wilhelm, D.M. Ladd and L.A. senses and provide a good introduction to Morris (eds.), The scientific management of Masters. 1997. Floristic quality assessment what prairies were once like. temperate communities for conservation. for vegetation in Illinois: A method London: Blackwell Scientific Publications. for assessing vegetation integrity. Erigenia Janes, D.H. 1986. The eternal external 15:3-95. ACKNOWLEDGMENTS threat. Pages 286-303 in M.E. Soul6 (ed.). Wesrman, W.E. 1991. Ecological restoration Conservation biology: The science of projects: Measuring their performance. The First I must thank the late Paul Shepard and Environmental Professional 13:207-215. George Ward who planned and started the scarcity and diversity. Sunderland, Massa- prairie restorations at Green Oaks, and Pete chusetts: Sinauer Associates, Inc. Schramm who maintained the original Kline, V.M. and E.A. Howell, 1987. Prairies. restorations and carried out new restorations. Pages 75-83 in W.R. Jordan 111, M.E. Gilpin Without their vision and efforts, my research and J. D. Aber (eds.), Restoration ecology: Dr. Stuart K. Allison is a professor in the would nor have been possible. I must also A synthetic approach to ecological research. Department of Biology at Knox College, Galesburg, thank the legions of Knox College students, Cambridge, England: Cambridge Univer- IL, 61401-4999; 309/341-7185. Fax 309/341- faculty, and staff who helped plant and main- sity Press. 7718. [email protected] . tain the prairies over the years. The Illinois Leach, M.K. and T.J. Giviiish. 1996.. Ecologi- Nature Preserves Commission kindly provided cal determinants of species loss in remnant permission for me to work at the Brownlee prairies. Science 273:1555-1558.

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