2007 NORTHEASTERN NATURALIST 14(1):35–50 Two Closed-canopy Barren Plant Communities in East-central Illinois William E. McClain1, Bobby R. Edgin2, Terry L. Esker3, and John E. Ebinger4,* Abstract - Pre-settlement barrens of Illinois were fire-maintained communities with an open tree canopy and a grass-dominated ground layer. Found on rolling topography, they were commonly underlain by well-drained, nutrient poor, clayey soils. Fire suppression following the arrival of the European settlers resulted in canopy closure and the loss of many prairie species that once dominated the ground layer. Both barrens studied had closed canopies due to decreased fire frequency, though both are currently being managed by fire. Quercus alba (white oak) and Q. stellata (post oak) dominated the overstory and accounted for more than 50% of the importance value. Very few shrubs, woody seedlings, and saplings were present, probably due to recent fires. Stephen A. Forbes State Park Barren in Marion County had been subjected to one burn before the study, and few prairie species were present there. The Buhnerkempe Barren in Clay County was subjected to occasional burns prior to our study and had higher prairie species diversity. Introduction Vestal (1936), while searching for descriptions of the natural vegetation of Illinois, was impressed by the frequent mention of barrens. Although he found little botanical information about them, he stated “their former generality of occurrence was evident. One wonders what they may have been like and what became of them.” Vestal (1936) suggested that small prairie openings in forests could be these “barren” remnants. More likely, however, he surmised that open Q. stellata (post oak) communities that were frequently swept by fires, and then were occupied by grassland plants, were the “barrens” of settlers and surveyors. These areas were definitely grasslands, but grasslands with an unusually high proportion of forest herbs and lacking many prairie species. He stated, “such vegetation might have been recognized by discriminating early residents and travelers as barrens rather than prairie.” Barrens within Illinois were described as a mixture of forest and prairie with a “scattering” of trees. “Gaudy wildflowers” were interspersed among the grasses, causing the barrens to be very attractive landscapes (Ellsworth 1838). The woody vegetation of barrens consisted of stunted Quercus stellata, Q. alba, Carya spp., Corylus americana, Rhus glabra, and R. copallina (Peck 1Illinois State Museum, Springfield, IL 62706. 2Illinois Nature Preserves Commission, One Natural Resources Way, Springfield, IL 62702. 3Illinois Department of Natural Resources, One Natural Resources Way, Springfield, IL 62702. 4Emeritus Professor of Botany, Department of Biological Sciences, Eastern Illinois University, Charleston, IL 61920. *Corresponding author - jeebinger@eiu.edu. 36 Northeastern Naturalist Vol. 14, No. 1 1837, Worthen 1868). “Grubs,” described by Peck (1837) as dwarfish oaks and hickories having massive root systems, gave the barrens a unique appearance. Presently, most authors consider barrens a transitional vegetation type containing grasses and forbs of both prairies and forests, a sparse growth of trees maintained by periodic fire and various species of fire-resistant shrubs (Anderson and Schwegman 1991). The soils of barrens were described as extremely fine, well-drained, white, sandy, arenaceous loam (Worthen 1868, 1870). These soils were sometimes very thin and often contained very little humus, a factor that contributed to their dryness in spring (Worthen 1868). Barrens also appeared to be fire-maintained communities. Bourne (1820) described the disappearance of the barrens once the Native Americans left the area. Until the early 1800s, occasional lightning strikes and the regular use of fire by the Native Americans maintained these open barren communities. When European settlers entered the region, most Native Americans left, and landscape fires were no longer common (McClain and Elzinga 1994). With this decrease in landscape fires, the open woodlands disappeared. Worthen (1868) also described barrens as fire-maintained communities, and Peck (1837) described the growth of vigorous sprouts from grubs once there were no more fires. By the 1860s, early botanists, travelers, and local residents were realizing that barrens were transient communities and, due to fire suppression, their replacement by forest would be completed within a relatively few years (Engelmann 1863, Hutchison 1987). Presently, few good quality examples of barrens exist in Illinois (Edgin 2000, Edgin et al. 2005, Taft 2003). Most have been degraded due to fire suppression and currently retain little of the species diversity and community structure that existed in the early 1800s. The few remaining recognizable “barrens” in Illinois have been subjected to occasional natural and management fires, have very poor quality soils, and have been left relatively undisturbed by human activity. In Illinois, these barrens were mostly restricted to regions of forest and savanna with rolling topography and clayey soils that were well-drained and nutrient poor (Bowles and McBride 1994, Bowles et al. 1994, Ebinger et al. 1994, Edgin et al. 2005, Homoya 1994, Taft 2003). Because this community is uncommon, attempts are presently being made to re-establish barrens in areas where they previously existed. The present study was undertaken to determine the present-day composition and structure of the vegetation of two sites that were barrens in early settlement times (based on early Government Land Office [GLO] survey records). Materials and Methods Description of the study area The closed-canopy barrens we studied were located in the Southern Till Plain Natural Division, an area subjected to glaciation approximately 125,000 years ago (Schwegman 1973). This region was dominated by prairie vegetation on the relatively flat uplands, while forests, woodlands, and 2007 W.E. McClain, B.R. Edgin, T.L. Esker, and J.E. Ebinger 37 barrens dominated areas of rugged topography associated with extensive drainage systems (Anderson 1991). The barrens studied were located on rolling topography and had many floristic similarities to post oak woodlands and forests on dry to dry-mesic sites. Both barrens were on hillsides, were less than 2 ha in size, had a few small tree-fall gaps in which some prairie vegetation was present, and one forest edge with a fence-row that opened onto an old field. Both barrens would presently be classified as mature second-growth, dry to dry-mesic upland forests due to high tree density (White and Madany 1978). Stephen A. Forbes State Park Barrens. Overlooking part of the long northern lobe of the Stephen A. Forbes Lake, this barrens was in Marion County, about 20 km northeast of Salem, IL (NW1/4 SE1/4 Section 32 Township 4N Range 4E). The soils were classified as Gosport loam with 25 to 45% slope. This moderately well-drained, very slowly permeable soil occurred on side slopes along drainage ways in strongly dissected areas of the till plain. The upper layer was moderately finely granular and was strongly acid (Mills 1996). The barrens had been subjected to a single burn in the fall of 2000. Buhnerkempe Barrens. Located in extreme northwestern Clay County about 8 km northwest of the small town of Iola, IL (NE1/4 SE1/4 Section 7 Township 5N Range 5E), the barrens was on a west-facing slope near Dismal Creek. The soils were classified as Hickory loam with 18 to 35% slope. This well-drained soil was located on side slopes along drainage ways in strongly dissected areas of the till plain. The upper layer had a fine granular structure and was moderately acidic (Endres 1998). Fall or early spring burns had occurred three times on the barrens in the past 10 years. The climate is continental, characterized by humid, hot summers and cold winters. Weather records for Salem, IL, recorded an average annual precipitation of 108 cm that falls mostly as rain from March through July (The Weather Channel 2004). January is the coldest month, with an average high temperature of 3 oC and an average low of -8 oC. July is the hottest month, with an average high of 31 oC and an average low of 20 oC. The frost-free growing period averages 205 days, with a low of 167 and a high of 232 days. Survey procedures The study sites were visited throughout the growing seasons of 2001 and 2002. Voucher specimens of each plant species were collected, identified, and deposited in the Stover-Ebinger Herbarium of Eastern Illinois University, Charleston, IL (EIU). Criteria for designating non-native species followed Mohlenbrock (2002) and Gleason and Cronquist (1991), while nomenclature follows Mohlenbrock (2002) (Appendix I). During the late summer of 2001, a 0.5-ha section of each study site (50 m x 100 m) was divided into 8 contiguous quadrats (25 m on a side) for ease in surveying. This study area was placed as near the middle of the site as possible to eliminate edge effect. In each quadrat, all living woody 38 Northeastern Naturalist Vol. 14, No. 1 individuals 􀂕 5.0 cm dbh were identified, and their diameters were recorded. From these data, the living-stem density (stems/ha), basal area (m2/ha), relative density, relative dominance (basal area), importance value (IV), and average diameter (cm) were calculated for each species. Determination of the IV followed the procedure used by McIntosh (1957), and is the sum of the relative density and relative dominance (basal area). The sapling and shrub layer was not surveyed, as very few live stems were present due to late-fall burns. To survey ground-layer vegetation, two transects 25 m long were located randomly in each study area. Along each transect, 1-m2 quadrats were located at 1-m intervals (n = 25/transect), odd-numbered quadrats to the right and even-numbered ones to the left. A random-numbers table was used to determine the number of meters (0 to 9) a quadrat was located from the transect line. Cover was determined by using the Daubenmire cover-class system (Daubenmire 1959) as modified by Bailey and Poulton (1968). Importance value for ground-layer species was determined by summing relative cover and relative frequency. Results A total of 198 plant species representing 56 families and 133 genera were documented for the two study sites (Appendix I). Of that total, one was a fern, 52 were monocots in eight families, and 145 were dicots in 47 families. Only seven non-native species were found, and 32 species of trees, shrubs, and woody vines were collected. The predominant families were Asteraceae with 34 species, Poaceae with 28 species, and Fabaceae with 14 species. Just over 20% of the native herbaceous taxa encountered were listed as prairie species (Appendix I). The overstory of both study sites was similar. Quercus alba and Q. stellata were the dominant species, accounted for more than 50% of the IV, and were well represented in all diameter classes (Table 1). Quercus velutina was also common, being third in IV on Forbes Barrens and fifth on Buhnerkempe Barrens. The genus Carya accounted for most of the remaining IV. Ground-layer vegetation was sparse on the study sites, bare ground and litter having cover values of 83.10 and 63.94 on Forbes and Buhnerkempe barrens, respectively (Tables 2 and 3). On both barrens, the dominant cover was woody seedlings and small sprouts of top-killed seedlings and small saplings. Seedlings and sprouts of Q. velutina were the most common component of the ground layer, with Q. alba and Rosa carolina also relatively common. Prairie herbs were not common on either barren. On Forbes Barrens, two graminoid species, Carex pensylvanica and Agrostis hyemalis, dominated. Graminoid taxa accounted for more than 50% of the herbaceous IV (Table 2). Only two prairie species, Euphorbia corollata and Liatris aspera, were found in the plots, and accounted for an IV of 2.2. Overall, 26 prairie 2007 W.E. McClain, B.R. Edgin, T.L. Esker, and J.E. Ebinger 39 Table 1. Densities by diameter classes (stems/ha), total density (stems/ha), basal areas (m2/ha), relative values, importance values (IVs) and average diameters of woody species in two barrens communities studied in east-central Illinois. Species with IVs less than 4.0 are included in the “others” category. Total Basal Average Diameter classes (cm) density area Relative Relative Importance diameter Species 5–10 10–19 20–29 30–39 40+ #/ha m2/ha density dominance value (cm) Steven A. Forbes State Park Barrens Quercus alba 30 6 26 40 44 146 12.808 29.4 53.7 83.1 30.1 Quercus stellata 12 22 14 16 16 80 5.272 16.1 22.1 38.2 25.5 Quercus velutina 24 24 6 10 10 74 3.662 14.9 15.4 30.3 20.0 Carya ovata 70 18 2 — — 90 0.572 18.1 2.4 20.5 18.2 Cary glabra 34 32 — — 2 68 1.026 13.7 4.3 18.0 11.6 Carya tomentosa 8 — — 4 — 12 0.416 2.4 1.7 4.1 15.9 Others (7 species) 26 — — — — 26 0.082 5.4 0.4 5.8 Totals 204 102 48 70 72 496 23.838 100.0 100.0 200.0 Buhnerkempe Barrens Quercus alba 10 40 68 52 6 176 9.876 28.8 43.6 72.4 25.2 Quercus stellata 4 54 92 22 — 172 7.546 28.1 33.3 61.4 22.7 Carya tomentosa 22 46 8 2 — 78 1.424 12.7 6.3 19.0 13.9 Carya ovata 20 30 6 — — 56 0.834 9.2 3.7 12.9 12.7 Quercus velutina 2 6 4 10 — 22 1.302 3.6 5.8 9.4 25.2 Acer saccharum 20 12 4 — — 36 0.396 5.9 1.7 7.6 10.5 Fraxinus americana 8 22 2 — — 32 0.500 5.2 2.2 7.4 13.2 Others (12 species) 28 4 4 2 2 40 0.752 6.5 3.4 9.9 Totals 114 214 188 88 8 612 22.630 100.0 100.0 200.0 40 Northeastern Naturalist Vol. 14, No. 1 species were found on the barrens, all being uncommon, mostly restricted to small tree-fall gaps and the barrens edge. In contrast, on Buhnerkempe Barrens, two woodland forbs, Helianthus divaricatus and Solidago ulmifolia, dominated. Graminoid taxa accounted for less than 15% of the herbaceous IV (Table 3). Six prairie species were found in the plots, all with IVs below 1.6, and three with IVs below 1.0, for a total IV of 5.7. Thirtynine prairie species were found in the barrens, mostly occurring beneath tree-fall gaps and at the barren edge (Table 3). Table 2. Frequency (%), mean cover (% of total area), relative frequency, relative cover, and importance value (IV) of herbaceous and woody species encountered in the ground layer in the fall of 2001 at Stephen A. Forbes State Park Barrens, Marion County, IL. Species with IVs less than 1.0 are included in the “others” category. Frequency Mean Relative Relative Importance Species (%) cover frequency cover value Herbaceous species Carex pensylvanica 52 0.46 11.4 3.2 14.6 Agrostis hyemalis 38 0.24 8.3 1.7 10.0 Apocynum androsaemifolium 12 0.74 2.6 5.2 7.8 Antennaria plantaginifolia 16 0.52 3.6 3.6 7.2 Carex hirsutella 22 0.21 4.8 1.5 6.3 Dichanthelium acuminatum 24 0.12 5.2 0.8 6.0 Aster turbinellus 22 0.16 4.8 1.1 5.9 Danthonia spicata 22 0.11 4.8 0.8 5.6 Helianthus divaricatus 6 0.37 1.3 2.6 3.9 Dichanthelium linearifolium 12 0.06 2.6 0.4 3.0 Lespedeza virginica 10 0.10 2.2 0.7 2.9 Aster anomalus 6 0.08 1.3 0.6 1.9 Aster patens 6 0.03 1.3 0.2 1.5 Elymus hystrix 6 0.03 1.3 0.2 1.5 Viola pedata 6 0.03 1.3 0.2 1.5 Carex glaucodea 4 0.02 0.9 0.2 1.1 Euphorbia corollata 4 0.02 0.9 0.2 1.1 Liatris aspera 4 0.02 0.9 0.2 1.1 Others (6 species) — 0.11 2.4 0.9 3.3 Woody species Quercus velutina 46 3.59 10.1 25.0 35.1 Quercus alba 28 2.95 6.1 20.6 26.7 Rosa carolina 36 0.82 7.9 5.7 13.6 Carya glabra 14 1.04 3.1 7.3 10.4 Carya ovata 6 0.90 1.3 6.3 7.6 Ostrya virginiana 8 0.38 1.8 2.7 4.5 Cercis canadensis 6 0.32 1.3 2.2 3.5 Prunus serotina 4 0.31 0.9 2.2 3.1 Crataegus pruinosa 6 0.18 1.3 1.3 2.6 Sassafras albidum 6 0.08 1.3 0.6 1.9 Carya cordiformis 4 0.12 0.9 0.8 1.7 Viburnum prunifolium 4 0.07 0.9 0.5 1.4 Others (3 species) — 0.13 1.2 0.5 1.7 Totals 14.32 100.0 100.0 200.0 Bare ground and litter 83.10 2007 W.E. McClain, B.R. Edgin, T.L. Esker, and J.E. Ebinger 41 Discussion Based on early literature and GLO survey notes, barrens were common throughout much of Illinois in the early 1800s, particularly in forested areas of rough topography. When describing barrens, the GLO surveyors generally mentioned the “scattering” of low, stunted, dwarfish oaks and hickories. These descriptions also commonly included remarks about the dense growth of oak and hickory brush often less than 3 m tall. Other Table 3. Frequency (%), mean cover (% of total area), relative frequency, relative cover, and importance value (IV) of herbaceous and woody species encountered in the ground layer in the fall of 2001 at Buhnerkempe Barrens, Clay County, IL. Species with IVs less than 1.0 are included in the “others” category. Frequency Mean Relative Relative Importance Species (%) cover frequency cover value Herbaceous species Helianthus divaricatus 92 10.93 12.7 30.0 42.7 Solidago ulmifolia 84 6.61 11.6 18.2 29.8 Aster turbinellus 28 2.00 3.9 5.5 9.4 Galium circaezans 40 0.40 5.5 1.1 6.6 Carex spp. 42 0.21 5.8 0.6 6.4 Dichanthelium latifolium 20 1.12 2.8 3.1 5.9 Porteranthus stipulatus 20 0.54 2.8 1.5 4.3 Carex pensylvanica 24 0.22 3.3 0.6 3.9 Ageratina altissima 14 0.51 1.9 1.4 3.3 Monarda bradburiana 14 0.27 1.9 0.7 2.6 Agrostis hyemalis 16 0.08 2.2 0.2 2.4 Elymus hystrix 14 0.07 1.9 0.2 2.1 Elymus virginicus 14 0.07 1.9 0.2 2.1 Bromus pubescens 12 0.06 1.6 0.2 1.8 Cinna arundinacea 10 0.05 1.4 0.1 1.5 Pycnanthemum tenuifolium 10 0.05 1.4 0.1 1.5 Solidago speciosa 4 0.31 0.6 0.9 1.5 Potentilla simplex 8 0.09 1.1 0.2 1.3 Verbesina helianthoides 8 0.09 1.1 0.2 1.3 Dichanthelium acuminatum 8 0.04 1.1 0.1 1.2 Parthenium integrifolium 6 0.13 0.8 0.4 1.2 Others (8 species) — 0.26 3.3 0.9 4.2 Woody species Quercus velutina 24 4.02 3.3 11.0 14.3 Rosa carolina 70 0.60 9.7 1.7 11.4 Fraxinus pennsylvanica 20 2.28 2.8 6.3 9.1 Symphoricarpos orbiculatus 36 1.40 5.0 3.9 8.9 Quercus imbricaria 14 0.66 1.9 1.8 3.7 Quercus alba 8 0.67 1.1 1.8 2.9 Carya ovata 6 0.66 0.8 1.8 2.6 Ceanothus americanus 6 0.66 0.8 1.8 2.6 Carya glabra 12 0.31 1.6 0.9 2.5 Cercis canadensis 4 0.31 0.6 0.9 1.5 Acer saccharum 2 0.30 0.3 0.8 1.1 Others (3 species) — 0.28 1.5 0.9 2.4 Totals 36.26 100.0 100.0 200.0 Bare ground and litter 63.94 42 Northeastern Naturalist Vol. 14, No. 1 descriptions mentioned the abundance of oak and hickory “grubs” along with considerable amounts of hazel, dwarf and smooth sumac, wild plum, and an undergrowth of grasses. According to the GLO survey notes, dense thickets of briers and vines were present in many barrens. One surveyor described a section of a Cretaceous Hills barren in extreme southern Illinois as “one continuous thicket of brush and briers beyond description” (McClain and Ebinger 2002). One of the more striking characteristics of the barrens described by the GLO surveyors was their size. Because we have only observed small remnants, we tend to think of barrens as being small, usually only a few hectares in size. According to the early GLO surveyors, however, barrens that covered several sections were once fairly common in Illinois. One of the largest and best-known barrens of pioneer times was the Cretaceous Hills barren, where federal surveyors described nearly 1000 hectares as barrens in 1806 (McClain and Ebinger 2002). Similarly, nearly all of the extensive ridge system that stretches from the southeastern part of Lawrence County into the southeastern part of Crawford County of east-central Illinois was originally described as barrens (Edgin 1996, 2000; Edgin and Ebinger 1997). In other studies using the GLO survey notes in southern Illinois, similar results were obtained. GLO notes of Williamson County mentioned that barrens were located on low ridges and hills and had a dense growth of tall grasses with a scattering of trees (Anderson and Anderson 1975). They attributed the absence of trees on the barrens to the annual fires that swept over the barrens. In this part of Illinois, the barrens merged into the post oak hills that were covered with a heavy growth of timber. Most of the areas described as barrens in the GLO notes were on rolling topography. The more rugged landscapes, where closed forests were common, do not carry fires as well as level or rolling landscapes where the barrens and prairies were found. A broad mosaic of prairie and oak-dominated forest, woodland, savanna, and barrens existed in Illinois at the time of European settlement during the early 1800s (Anderson 1983, Davis 1977). Climatically induced and maintained by fire, most timbered lands persisted on the lee side of topographic and wetland fire breaks. Fire frequency and intensity were important in determining the composition and structure of wooded areas: intense and frequent fires created prairie and savanna, while less intense and less frequent fires caused barrens and woodlands (Ebinger and McClain 1991). Due mostly to fire suppression, few examples of barrens existed by the early 1900s, causing botanists to speculate on their floristic composition and community structure (Vestal 1936). Present information suggests that most upland forests in Illinois were relatively open (Anderson and Anderson 1975, Ebinger and McClain 1991) and could be characterized as open woodlands, savannas, or barrens depending upon tree densities and community structure. These open-canopy forests represented a transition between prairies and closed forests of the dissected 2007 W.E. McClain, B.R. Edgin, T.L. Esker, and J.E. Ebinger 43 terrain of river valleys. At the time of European settlement, these open woodlands, savannas, and barrens were fashioned by climate, topography, edaphic factors, and periodic fires (Heikens and Robertson 1994, McClain and Elzinga 1994). With the cessation of landscape fires, woody plant encroachment usually resulted in canopy closure, except where edaphic factors slowed tree growth. Native Americans were responsible for most of these fires (Davies 1994, McClain and Elzinga 1994, Williams 1989). A few examples of high-quality barrens are known from the Southern Illinois Till Plain Natural Division (Schwegman 1973). The pre-settlement vegetation of Beadles Barrens Nature Preserve was open woodland interspersed with prairie. Situated in a forest-prairie interface zone, a few large oaks and hickories were scattered through the 4.0-ha site. The ground layer was mostly dry prairie vegetation; Schizachyrium scoparium, Solidago nemoralis, and Pychanthemum tenuifolium accounted for 107.9 of the IV (Edgin et al. 2005). Another area that has retained the barren aspect was Gray’s Post Oak Woodland in Saline County, IL. On this community, about 3.0 ha in size, the overstory was dominated by Quercus stellata (Edgin et al. 2004). Overstory trees averaged 422 stems/ha, but the canopy was very open, probably due to the trees being stunted and gnarled by the clayey lakebed deposits on which the site is situated. Danthonia spicata, Carex spp., Helianthus divaricatus, mosses, and lichens accounted for 158.8 of the total ground-layer IV. Heikens and Robertson (1995) found that the barrens of the Shawnee Hills in southern Illinois were consistently characterized by open-grown trees (mostly Quercus stellata and Q. marilandica), with Ulmus alata the common subcanopy species, and the ground layer a mixture of prairie and dry woodland herbaceous species. On their sites, the overall herbaceous cover was 15.9% and overall canopy cover was 49.4 percent, while the total number of species found in the barrens habitat was 129. In the barrens of the Southern Till Plain examined in the present study, Q. alba, Q. stellata, and Q. vetuina were important overstory species. Many of the understory species listed by Heikens and Robertson (1995) were the same as those reported in the present study. Degraded examples of barrens are common throughout areas of rough topography in southern Illinois, but most are in desperate need of management, particularly periodic fire. Before much of the region became the Shawnee National Forests in the 1930s, property owners commonly used yearly fires to “clear out the understory” (Anderson and Schwegman 1991, McClain and Elzinga 1994, Miller 1920). Since being incorporated into the Shawnee National Forest, the general practice has been to protect these forests from wildfires. Within the past 15 to 20 years, however, occasional management burns have been used to open the canopy of some barren remnants. Attempts are currently being made by biologists from the Illinois Department of Natural Resources to reconstruct barrens (Taft 2003). Prescribed 44 Northeastern Naturalist Vol. 14, No. 1 fire is being used to open the canopy where prairie species are occasional-tocommon members of the flora. It is anticipated that frequent fires will continue to open the canopy, but it is possible that aggressive removal of some trees may be necessary. Though woody and herbaceous species are present, the time required for the development of grubs and an increased density of shrubs, as described in the 1800s, is not known. Acknowledgments The authors would like to thank the Illinois Department of Natural Resources for permission to examine the barrens at Steve A. Forbes State Park, and Mr. Roger Buhnerkempe from Watson, IL, for permission to do the vegetation analysis on Buhnerkempe Barrens. Literature Cited Anderson, R.C. 1983. The eastern prairie-forest transition: An overview. Pp. 86–92, In R. Brewer (Ed.). Proceedings of the Eighth North American Prairie Conference. Western Michigan University, Kalamazoo, MI. Anderson, R.C. 1991. Presettlement forests of Illinois. Pp. 9–19, In G.V. Burger, J.E. Ebinger, and G.S. Wilhelm (Eds.). Proceedings of the Oak Woods Management Workshop. 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Journal of the Torrey Botanical Society 130:170–192. Vestal, A.G. 1936. Barrens vegetation in Illinois. Transactions of the Illinois State Academy of Science 29:29–30. The Weather Channel. 2004. Records for Harrisburg, Illinois. Available online at http://www.weather.com. White, J., and M.N. Madany. 1978. Classification of natural communities in Illinois. Pp. 309–405, In J. White (Ed.). Illinois Natural Areas Inventory, Technical Report. Illinois Natural Areas Inventory, Urbana, IL. Williams, M. 1989. Americans and Their Forests: A Historical Geography. Cambridge University Press, NY. Worthen, A.H. 1868. Geological Survey of Illinois, Volume 3. State Journal Steam Press, Springfield, IL. 502 pp. + appendices. Worthen, A.H. 1870. Geological Survey of Illinois, Volume 4. State Journal Steam Press, Springfield, IL. 572 pp. + appendices. 2007 W.E. McClain, B.R. Edgin, T.L. Esker, and J.E. Ebinger 47 Appendix I. Vascular taxa encountered at east-central Illinois barren communities listed alphabetically by family under major plant groups. An asterisk (*) indicates species that mostly occur in prairies and other open habitats. The barrens where each species was found is indicated b = Buhnerkempe Barrens, f = Forbes Barrens. FERN AND FERN ALLIES Aspleniaceae Asplenium platyneuron (L.) Oakes: b, f MONOCOTS Araceae Arisaema dracontium (L.) Schott: f Commelinaceae *Tradescantia virginiana L.: b, f Cyperaceae Carex albicans Willd.: b Carex blanda Dewey: b, f Carex cephalophora Muhl.: b, f Carex glaucodea Tuckerm.: f Carex gracilescens Steud.: b, f Carex grisea Wahl.: b Carex hirsutella Mack.: b, f Carex muhlenbergii Schk.: f Carex normalis Mack.: b Carex pensylvanica Lam.: f Carex retroflexa Muhl.: b, f Carex rosea Schk.: b Dioscoreaceae Dioscorea villosa L.: b, f Iridaceae *Sisyrinchium albidum Raf.: b Juncaceae *Juncus interior Wieg.: b Juncus tenuis Willd.: f Liliaceae *Allium canadense L.: b Polygonatum biflorum (Walt.) Ell.: f Smilacina racemosa (L.) Desf.: b Trillium recurvatum Beck: b Orchidaceae Liparis liliifolia (L.) Rich.: b, f *Spiranthes cernua (L.) Rich.: b, f Poaceae Agrostis hyemalis (Walt.) BSP.: b, f Agrostis perennans (Walt.) Tuckerm.: f *Andropogon gerardii Vitman: b Bromus pubescens Muhl.: b, f Cinna arundinacea L.: b Danthonia spicata (L.) Roem. & Schultes: b, f Dichanthelium acuminatum Gould & Clark: b, f Dichanthelium boscii Gould & Clark: b, f *Dichanthelium depauperatum Gould: b, f Dichanthelium latifolium Gould & Clark: b, f Dichanthelium linearifolium Gould: f Dichanthelium polyanthes Mohlenbr.: f Dichanthelium sphaerocarpon Gould: f Elymus x ebingerii G.C. Tucker: b Elymus hystrix L.: b, f Elymus virginicus L.: b, f Festuca subverticillata E.B. Alexeev.: b, f Glyceria striata (Lam.) Hitchc.: f Leersia virginica Willd.: f Muhlenbergia frondosa (Poir.) Fern.:b Muhlenbergia sobolifera (Muhl.) Trin.: b, f Muhlenbergia sylvatica (Torr.) Torr.: f Poa compressa L.: b, f Poa pratensis L.: b, f *Schizachyrium scoparium (Michx.) Nash: b Sphenopholis obtusata (Michx.) Scribn.: f *Tridens flavus (L.) Hitchc.: b, f Vulpia octoflora (Walt.) Rydb.: f DICOTS Acanthaceae *Ruellia humilis Nutt.: b Ruellia strepens L.: f 48 Northeastern Naturalist Vol. 14, No. 1 Aceraceae Acer saccharum Marsh.: b Anacardiaceae Rhus copallina L.: b Toxicodendron radicans (L.) Kuntze: b, f Apiaceae Sanicula canadensis L.: b, f Taenidia integerrima (L.) Drude: b, f Thlaspium barbinode (Michx.) Nutt.: b Zizia aurea (L.) Koch: b Apocynaceae Apocynum androsaemifolium L.: b, f Aristolochiaceae Aristolochia sepentaria L.: b, f Asclepiadaceae *Asclepias verticillata L.: b Asteraceae Achillea millefolium L.: b Ageratina altissima (L.) King & Robins.: b, f Antennaria plantaginifolia (L.) Hook.: b, f Aster anomalus Engelm.: f Aster lateriflorus (L.) Britt.: b, f *Aster novae-angliae L.: b *Aster oolentangiensis Riddell: b Aster ontarionis Wieg.: b Aster patens Ait.: f Aster sagittifolius Willd.: b, f Aster turbinellus Lindl.: b, f Cirsium altissimum (L.) Spreng.: b *Coreopsis palmata Nutt.: b, f *Coreopsis tripteris L.: b *Echinacea purpurea (L.) Moench.: b *Erigeron annuus (L.) Pers.: b, f *Erigeron strigosus Muhl.: b, f Helianthus divaricatus L.: b, f Hieracium gronovii L.: b, f Hieracium scabrum Michx.: f Krigia virginica (L.) Willd.: f *Lactuca canadensis L.: f Lactuca floridana (L.) Gaertn.: b *Liatris aspera Michx.: b, f *Parthenium integrifolium L.: b, f *Rudbeckia hirta L.: b, f *Silphium terebinthinaceum Jacq.: b *Solidago canadensis L.: b *Solidago missouriensis Nutt.: b *Solidago nemoralis Ait.: b, f *Solidago speciosa Nutt.: b Solidago ulmifolia Muhl.: b, f Verbesina helianthoides Michx.: b, f *Vernonia gigantea (Walt.) Trel.: b, f Berberidaceae Podophyllum peltatum L.: b, f Bignoniaceae Campsis radicans (L.) Seem.: b, f Brassicaceae Arabis canadensis L.: f Cardamine parviflora L.: f Caesalpiniaceae *Chamaechrista nictitans (L.) Moench.: f Cercis canadensis L.: b, f Gleditsia triacanthos L.: f Campanulaceae Lobelia inflata L.: b, f *Lobelia spicata Lam.: f Triodanis perfoliata (L.) Nieuwl.: f Caprifoliaceae Symphoricarpos orbiculatus Moench.: b, f Triosteum illinoense (Wieg.) Rybd.: b Viburnum prunifolium L.: f Caryophyllaceae Cerastium fontanum Baum: b Dianthus armeria L.: f Paronychia canadensis (L.) Wood.: b Paronychia fastigata (Raf.) Fern.: b, f Silene stellata (L.) Ait. f.: b, f Convolvulaceae Calystegia spithamaea (L.) Pursh.: b, f Corylaceae Corylus americana Walt.: f Ostrya virginiana (Mill.) Koch: b, f 2007 W.E. McClain, B.R. Edgin, T.L. Esker, and J.E. Ebinger 49 Ebenaceae Diospyros virginiana L.: b, f Euphorbiaceae Acalypha virginica L.: f *Euphorbia corollata L.: b, f Fabaceae Amphicarpaea bracteata (L.) Fern.: b, f *Baptisia bracteata Ell.: b, f *Crotalaria sagittalis L.: b Desmodium cuspidatum (Muhl.) Loud.: f Desmodium glutinosum (Muhl.) Wood: b Desmodium nudiflorum (L.) DC.: b, f Desmodium rotundifolium DC.: f Lespedeza intermedia (S. Wats.) Britt.: f Lespedeza procumbens Michx.: b, f Lespedeza virginica (L.) Britt.: b, f *Orbexilum pedunculatum (Miller) Rydb.: b, f Robinia pseudoacacia L.: b Stylosanthes biflora (L.) BSP.: b, f Tephrosia virginiana (L.) Pers.: b Fagaceae Quercus alba L.: b, f Quercus imbricaria Michx.: b, f Quercus stellata Wangh.: b, f Quercus velutina Lam.: b, f Gentianaceae Frasera caroliniensis Walt.: b Geraniaceae Geranium maculatum L.: b Hypericaceae Hypericum punctatum Lam.: b, f Juglandaceae Carya cordiformis (Wang.) Koch: f Carya glabra (Mill.) Sweet: f Carya ovata (Mill.) Koch: b, f Carya tomentosa (Poir.) Nutt.: b, f Lamiaceae *Blephilia ciliata (L.) Benth.: f *Hedeoma pulegioides (L.) Pers.: f Monarda bradburiana Beck: b, f Prunella vulgaris L.: b *Pycnanthemum tenuifolium Schrad.: b, f Scutellaria australis (Fassett) Epling: f Scutellaria incana Biehler: f *Scutellaria leonardii Epling: b Lauraceae Sassafras albidum (Nutt.) Nees: b, f Oxalidaceae Oxalis stricta L.: b, f Passifloraceae Passiflora lutea L.: b Phyrmaceae Phryma leptostachya L.: b, f Phytolaccaceae Phytolacca americana L.: f Polemoniaceae Phlox divaricata L.: b, f *Phlox pilosa L.: b Polygalaceae Polygala verticillata L.: b, f Portulacaceae Claytonia virginica L.: b Primulaceae Dodecatheon meadia L.: b Lysimachia lanceolata Walt.: f Ranunculaceae Delphinium tricorne Michx.: b Rhamnaceae *Ceanothus americanus L.: b, f Rosaceae Agrimonia rostellata Wallr.: b, f Crataegus pruinosa (Wendl.) Koch: f Geum canadense Jacq.: b, f Geum vernum (Raf.) Torr. & Gray: f Porteranthus stipulatus (Michx.) Britt.: b, f 50 Northeastern Naturalist Vol. 14, No. 1 Potentilla simplex Michx.: b, f Prunus serotina Ehrh.: b, f *Rosa carolina L.: b, f *Rubus flagellaris Willd.: b, f Rubus occidentalis L.: f Rubus pensylvanicus Poir.: b, f Rubiaceae Galium aparine L.: b, f Galium circaezans Michx.: b, f Galium concinnum Torr. & Gray: b, f Galium pilosum Ait.: b Houstonia purpurea L.: b, f Santalaceae *Comandra umbellata (L.) Nutt.: f Saxifragaceae Heuchera americana L.: b, f Scrophulariaceae Aureolaria flava (L.) Farw.: f *Penstemon digitalis Nutt.: b, f *Penstemon pallidus Small: b, f Solanaceae Physalis heterophylla Nees: f Ulmaceae Ulmus rubra Muhl.: f Urticaceae Parietaria pensylvanica Muhl.: f Violaceae Viola pedata L.: f Viola sororia Willd.: f Vitaceae Parthenocissus quinquefolia (L.) Planch.: b, f Vitis aestivalis Michx.: b, f Vitis cinerea Engelm.: f