Folly Mills Calcareous Wetland

Augusta County, Virginia

Robert Hunsucker and R. F. Mueller

Abstract
The Folly Mills wetland in Augusta County, Virginia originates from artesian springs in an area of dolomitic limestone. The wetland is the site of a number of state rare plants. These include such disjunct northern species as Carex interior, C. prairea, Juncus brachycephalus, J. nodosus, Menyanthes trifoliata, Spiranthes lucida, Lysimachia quadriflora, Salix discolor, Filipendula rubra and Veronica scutellata. Parnassia grandifolia and the moss Philonotis muehlenbergii also occur here. The wetland is the only known site in the state for Salix discolor and one of only two extant populations of Menyanthes. It appears to be a true island refugium dating to glacial times. The character of the spring water, a topographic trap, presence of herbivores and other factors may affect continuing existence of the community. The most important consideration in protecting this wetland is preservation of its watershed and spring recharge area.

Introduction
Calcareous wetlands constitute a very restricted class of habitats in the Central Appalchians and thus far have received little attention in the literature (T. F. Wieboldt, personal communication, 1996). Perhaps the best-known example of this community type in the Central Appalachians is the Altona Marsh in Jefferson County, West Virginia (Hutton et al, 1968; Strausbaugh and Core, 1978). Somewhat similar wetlands in Ohio have been studied by Stuckey and Denny (1981), but these occur in the area of the most recent glaciation. A nearby wetland at Stuarts Draft, Virginia, shares a number of state rare species, including Buckbean (Menyanthes trifoliata), with the Folly Mills wetland (The Nature Conservancy, Virginia Chapter News, 1995). Another example, the Barns Chapel Swamp of Washington County, Virginia (Ogle, 1989) has similar soil chemistry and shares at least 15 species with Folly Mills. However there are also many species not shared by the two wetlands, perhaps in part as a result of their separation by the eastern continental divide. Like these examples, the Folly Mills wetland is notable for its rare and disjunct northern species, which number at least ten.

In addition to the interest these rare plants in themselves afford, the communities in which they occur pose questions regarding their origin, persistence in time and relations to coexisting fauna both today and in earlier times. If, as it appears, the disjunct northern species are ice-age relicts, what are the conditions for continuing maintenance of the community? What was and is the role of natural disturbances such as fire and herbivore grazing and browsing? There is good evidence that a megafauna of large herbivores and carnivores existed in the region during late glacial times, up to perhaps 11,000 years ago (Guilday, 1984). Given the scarcity of wetlands in this unglaciated region, such places were likely magnets for both herbivores and carnivores for the special foraging and wallowing opportunities provided. To a degree the same should have been true of the Holocene Bison, Elk and other animals that once populated the area before settlement by Europeans. Presettlement conditions, which presumably favored the establishment and persistence of these communities, would seem to be desirable for their protection and management today.

Setting

The Folly Mills wetland is located on the floodplain of Folly Mills Creek, a headwater branch of the South Fork of the Shenandoah River. A major fork of the stream lies just to the southeast upstream. Bedrock in the area is Ordovician Beekmantown dolomitic limestone with prominent chert beds (Rader, 1967). Local relief in the area is about 300 ft (90 meters) and the wetland lies at 1590 ft (480 meters) asl. Approximately 4 acres (1.6 ha) in area, it occupies an embayment in a linear ridge that rises 120 ft (37 meters) on the northwest. This ridge consists of bluish gray dolomitic limestone which exhibits some coarse crystals of dolomite. The ridge is capped by a massive bed of chert which is partly exposed and partly covered by soil. The wetland is bounded on the southeast by the natural levee of the stream. The main water source of the wetland appears to be a large artesian spring that wells up within it. The flow of this spring, which is distributed over a wide area, has built up marly clay deposits that have elevated the surface a foot or more above the floodplain behind the levee. It is possible that the embayment in the hillside is also at least in part a result of rock dissolution by the spring. Because Folly Mills Creek is subject to extensive flooding, the wetland is occasionally inundated to depths of a meter or more and thus receives nutrient-rich alluvial deposits as a result.

Table 1 summarizes the chemical characteristics of the wetland soils at depths of 0-10 and 10-20 cm at locations on the southeast (FM1) and northwest (FM2) sides. Organic matter is particularly high in the surface samples. pH ranges from slightly acid to slightly alkaline. Ca and Mg are high in all samples, while P, K and soluble salts are low. Fe and some trace elements appear to be concentrated in the surface organic matter.

The forest on the surrounding hills ranges from young to mature. While it can be classified Oak-Chestnut as a whole (Braun, 1950) it shows considerable variation in type, depending on aspect, slope and proximity to given rock types. Oaks and Hickories dominate on chert ridges and some deep soil areas as northwest of the wetland. However, on slopes immediately above the wetland mesic species such as Juglans nigra, Ulmus rubra, Celtis occidentalis and Morus rubra are abundant. The herb flora in such areas is rich and diverse and includes such species as Panax quinquefolius and Hydrastis canadensis. Where carbonate rocks are near the surface there is a community dominated by Quercus muehlenbergii and Fraxinus americana. This Ash also borders the wetland on the floodplain. A determination in soil above carbonate yielded a pH of 7.7 but measurements above chert ranged from 6.0 at the surface to 5.1 a foot (30 cm) below the surface. pH is also expected to be lower on chert talus and areas of oak leaf concentrations. It is likely that run-off from such areas exerts some influence on wetland chemistry, and it is possible that the significantly lower pH value of sample FM2 from the forest side of the wetland,relative to that of FM1 on the steam side, reflects this influence.

Although local relief is not great, the topography of the Folly Mills Valley has significant features that bear on the wetland microclimate. The Valley upstream rises to 2200 ft (670 meters) asl at the headwater divide five miles (8 km) to the southwest. Less than 1/4 mile (400 meters) below it is constrained to a width of less than 100 feet (30 meters) and forms a bottleneck for both water and cold air draining from up valley. One consequence is that killing frosts have been recorded near the wetland as late as June 8.

Destructive farming practices gullied the hills and contributed subsoil sediment to the floodplain and wetland. About 40 years ago an attempt was made to drain the wetland by ditching to the stream and these ditches as well as the material removed from them are still clearly recognizable. However there was apparently little effect on the wetland due to the high volume of spring water flow. This flow is remarkably constant with little apparent diminution during even the driest weather of the last twenty years.

List of the Wetland Plants
* = denotes State-rare listing for Virginia, with Global and State ranking (Ludwig, 1995, 1996).

I. Bryophytes (Taxonomy follows Crum and Anderson 1981)
Amblystegium riparium (Hedw.) BSG. Frequent. Occurs throughout the U.S.
Brachythecium oxycladon (Brid.) Jaerg. & Sauerb. Frequent. A wide ranging species in eastern U.S.
Drepanocladus aduncus (Hedw.) Warnst. var aduncus. Frequent. Alaska to Quebec, s. to Va, Pa, Mo, Nev and Calif. In wet, calcareous habitats.
Hypnum lindbergii (Mitt.) Common. Circumpolar and South to gulf Coast.
Mnium affine var. rugicum (Laur) ESG. Frequent. Wide ranging in North America in calcareous habitats.
Mnium cuspidatum (Hedw.) Frequent. Widespread in North America in various habitats.
Philonotis marchica (Hedw.) Brid. Frequent. Widespread in the U.S. in wet places, eastern Canada to Minn, Ga, and Tex.
*Philonotis muehlenbergii (Schwaegr.) Brid. Infrequent or rare. Maine to North Carolina, west to British Columbia and Arizona. G3G4S?

II. Vascular Plants; Arranged alphabetically by families, genera, and species. (taxonomy follows Cronquist, 1991)
Alismataceae (Water-Plantain Family)
Alisma subcordatum Raf. Southern Water Plantain. Infrequent.
Apiaceae (Carrot Family)
Cicuta maculata L. Common Waterhemlock. Infrequent.
Cryptotaenia canadensis (L.)DC. Honewort. Infrequent where marsh and wood meet.
Oxypolis rigidior (L.) Raf. Cowbane. Frequent.
Ptilimnium capillaceum (Michx.) Raf. Mock Bishopweed. Infrequent.
Araceae (Arum Family)
Peltandra virginica (L) Schott and Endl. Arrow Arum. Rare.
Symplocarpus foetidus (L.) Nutt. Skunk Cabbage. Frequent.
Asclepiadaceae (Milkweed Family)
Asclepias incarnata L. Swamp Milkweed. Infrequent.
Aspleniaceae (Spleenwort Family)
Thelypteris palustris Schott. Marsh Fern. Frequent.
Asteraceae (Aster Family)
Ambrosia artemisiifolia L. Common Ragweed. Infrequent.
Ambrosia trifida L. Giant Ragweed. Infrequent.
Aster novae-angliae L. New England Aster. Infrequent.
Aster lanceolatus Willd. (A. simplex). Eastern Lined Aster. Infrequent.
Aster prenanthoides Muhl. Zig Zag Aster. Infrequent.
Aster puniceus L. Bristly Aster. Frequent.
Bidens cernua L. Bur Marigold. Infrequent.
Bidens connata Muhl. (B. tripartita). Purplestem Beggar Ticks. Frequent.
Bidens frondosa L. Devil's Beggarticks. Frequent.
Eupatorium fistulosum Barratt. Joe Pye Weed. Frequent.
Eupatorium perfoliatum L. Boneset. Frequent.
Helenium autumnale L. Common Sneezeweed. Frequent.
Helianthus giganteus L. Swamp Sunflower. Infrequent.
Senecio aureus L. Golden Ragwort. Frequent.
Solidago gigantea Ait. Smooth Goldenrod. Infrequent.
Verbesina alternifolia (L.) Britton. Wingstem. Frequent.
Vernonia noveboracensis (L.) Michx. New York Ironweed. Frequent.
Balsaminaceae (Touch-me-not Family)
Impatiens capensis Meerb. Jewelweed. Frequent.
Brassicaceae(Mustard Family)
Cardamine rhomboidea (Pers.) DC. (C. bulbosa). Spring Cress. Infrequent.
Rorippa nasturtium-aquaticum (L.) Hayik. Watercress. Infrequent. Introduced.
Campanulaceae(Bellwort Family)
Campanula aparinoides Pursh. Marsh Bellflower. Rare.
Lobelia siphilitica L. Great Blue Lobelia. Frequent.
Chenopodiaceae (Goosefoot Family)
Chenopodium album L. Lambs Quarters. Infrequent. Introduced.
Clusiaceae (Hypericaceae) (Mangosteen Family)
Hypericum mutilum L. Small-Flowered St. Johnswort. Frequent.
Cuscutaceae (Dodder Family)
Cuscuta compacta A. L. Juss. Dodder. Infrequent.
Cyperaceae (Sedge Family)
Carex alata T. & G. Infrequent.
Carex frankii Kunth. Infrequent.
Carex granularis Muhl. Infrequent.
Carex hystricina Muhl. Rare.
*Carex interior L. Bailey. Frequent. G5S1
Carex lurida Wahl. Frequent.
*Carex prairea Dewey. Frequent. G5S1
Carex scoparia Schk. Frequent.
Carex stricta Lam. Rare.
Carex vulpinoidea Mich. Infrequent.
Cyperus polystachyos Roth. Infrequent.
Cyperus strigosus L. Infrequent.
Eleocharis palustris var. calva Gray. Frequent.
Scirpus atrovirens Willd. Black Bulrush. Infrequent.
Scirpus pendulus Muhl. (S. lineatus). Infrequent.
Scirpus validus Vahl. Softstem Bulrush. Frequent.
Fabaceae (Bean Family)
Amphicarpa bracteata (L.) Fern. Hog Peanut. Frequent.
Hydrocharitaceae (Frog's-bit Family)
Elodea canadensis Michx. Canada Waterweed. Rare.
Juncaceae (Rush Family)
*Juncus brachycephalus (Engelm.) Buchenau. Frequent. G5S1
Juncus effusus L. Soft Rush. Infrequent.
Juncus marginatus Rostk. Infrequent.
*Juncus nodosus L. Rare. G5S1
Juncus tenuis Willd. var. tenuis. Infrequent
Juncus tenuis var. dudleyi (Wieg.) F.J. Herm. (J. dudleyi) Rare.
Lamiaceae (Mint Family)
Lycopus americanus Muhl. Water Horehound. lnfrequent.
Lycopus uniflorus Michx. Northern Water Horehound. Frequent.
Mentha arvensis var. canadensis (L.) Kuntze. Field Mint. Frequent.
Mentha hybrid. (M. arvensis X M. piperita) Frequent.
Mentha piperita L. Peppermint. Frequent. Introduced.
Prunella vulgaris L. Heal All. Frequent. Introduced.
Pycnanthemum tenuifolium Schrader. Mountain Mint. Frequent.
Pycnanthemum virginianum (L.) Durand & Jackson. Mountain Mint. Frequent.
Scutellaria lateriflora L. Maddog Skullcap. Infrequent.
Lemnaceae (Duckweed Family)
Lemna valdiviana Philippi. Duckweed. Frequent.
Menyanthaceae (Buckbean Family)
*Menyanthes trifoliata L. Buckbean. Frequent. G5S1
Onagraceae(Evening Primrose Family)
Epilobium coloratum Biehler. Eastern Willow Herb. Frequent.
Ludwigia alternifolia L. Square-pod Water-primrose. Infrequent.
Ludwigia palustris (L.) Elliott. Common Water-purslane. Frequent.
Orchidaceae (Orchid Family)
Spiranthes cernua (L). Rich. Nodding Ladies Tresses. Rare.
*Spiranthes lucida (H. Eaton) Ames. Shining Ladies Tresses. Rare. G5S1
Platanaceae (Sycamore Family)
Platanus occidentalis L. Sycamore. Infrequent.
Poaceae (Grass Family)
Agrostis stolonifera L. Creeping Bent. Frequent. Introduced.
Echinochloa muricata (P. Beauv.) Fern. Barnyard Grass. Infrequent.
Glyceria striata (Lam.) A. Hitchc. Fowl Mannagrass. Frequent.
Leersia oryzoides (L.) Swartz. Rice Cutgrass. Frequent.
Leersia virginica Willd. Whitegrass. Occasional.
Panicum dichotomiflorum Michx. Spreading Witchgrass. Infrequent.
Poa unidentified (specimens possess characteristics of Poa pratensis and P. trivialis). Infrequent. Introduced.
Puccinellia pallida (Torr.) R. T. Clausen (Glyceria pallida, G. fernaldii). Mannagrass. Rare.
Sphenopholis intermedia (Rydb.) Rydb. Wedgegrass. Rare.
Trisetum pensylvanicum (L.) Beau. Wedgegrass. Rare.
Polygonaceae (Smartweed Family)
Polygonum persicaria L. Lady's Thumb. Infrequent. Introduced.
Polygonum punctatum Elliott. Dotted Smartweed. Frequent.
Primulaceae (Primrose Family)
*Lysimachia quadriflora Sims. Smooth Loosestrife. Frequent. G5S1
Samolus parviflorus Raf. Water Pimpernel. Infrequent.
Ranunculaceae (Buttercup Family)
Caltha palustris L. Marsh Marigold. Frequent.
Ranunculus carolinianus DC. (R. septentrionalis) Northern Swamp Buttercup. Infrequent.
Thalictrum pubescens Pursh (T. polygamum). Tall Meadowrue. Infrequent.
Rosaceae (Rose Family)
Agrimonia gryposepala Wallr. Tall Agrimony. Frequent.
*Filipendula rubra (Hill) B.L.. Robinson. Queen of the Prairie. Infrequent. G4G5S2
Geum canadense Jacq. White Avens. Infrequent.
Rubiaceae (Madder Family)
Galium asprellum Michx. Rough Bedstraw. Frequent.
Salicaceae (Willow Family)
*Salix discolor Muhl. Pussy Willow. Frequent. G5S1
Salix eriocephala Michx. (S. rigida). Diamond Willow. Frequent.
Salix sericea Marshall. Silky Willow. Frequent.
Saxifragaeae(Saxifrage Family)
*Parnassia grandifolia DC. Large-Leaved Grass-of-Parnassus. Rare. G4G5S2
Penthorum sedoides L. Ditch Stonecrop. Infrequent.
Scrophulariaceae ( Figwort Family)
Agalinis purpurea (L.) Purple Gerardia. Frequent.
Chelone glabra L. White Turtlehead. Infrequent.
Mimulus ringens L. Allegheny Monkeyflower. Frequent.
Pedicularis lanceolata Michx. Swamp Lousewort. Frequent.
Penstemon laevigatus Ait. Eastern Beardtongue. Infrequent
Veronica anagallis-aquatica L. Water Speedwell. Infrequent.
*Veronica scutellata L. Marsh Speedwell. Rare. G5S1
Selaginellaceae (Spikemoss Family)
Selaginella apoda (L.) Spring. Meadow Spikemoss. Frequent.
Sparganiaceae (Burreed Family)
Sparganium americanum Nutt. Burreed. Infrequent.
Typhaceae (Cattail Family)
Typha latifolia L. Frequent Cattail. Frequent.
Urticaceae (Nettle Family)
Pilea pumila (L.) A. Gray Clearweed. Frequent.
Verbenaceae (Vervain Family)
Verbena urticifolia L. White Vervain. Infrequent.
Violaceae (Violet Family)
Viola cucullata Ait. Blue Marsh Violet. Frequent.



Summary

Total of 121 species of mosses, fern, spikemoss and flowering plants:
8 spp of bryophytes
114 species of vascular plants: ferns 1, Spikemoss 1, flowering plants 108
12 out of 121 species are of special concern, rare etc.; 1 moss, 11 flowering plant species
7 of the flowering plant species are not native (introduced from Europe)


Plant Distribution in the Wetland
The wetland consists of two major parts, a central cattail marsh and a sedge-forb meadow that surrounds the marsh. Species other than cattails that are concentrated in the marsh are Peltandra virginica, Impatiens capensis, Lemna valdiviana, Pilea pumila, Caltha palustris and Menyanthes trifoliata. Menyanthes also extends into the meadow. During the dormant season the location of the Buckbean in the marsh is clearly visible on ærial photos since there are fewer cattails where Buckbean occurs.

Virtually all plants other than those listed above are greatly concentrated in the sedge-forb meadow. Some of the largest Pussy Willows, which range up to 15 ft (4.6 meters) high, are located on the northwest edge of the wetland and almost merge with the upland forest. However other lower shrubs of this and other willows are scattered in both meadows and marsh.

Although Caltha palustris, like Buckbean, is concentrated in the marsh, it is largely separated from the latter and confined to the northeast end.

Filipendula rubra occurs mostly where the marsh and meadow meet and not far from the upland forest edge on the northwest side of the marsh. Although of very limited occurrence, Parnassia grandifolia is to some extent associated with willow clumps in the meadow.

Discussion
The majority of plants of the Folly Mills Wetland have wide distributions ranging from southern Canada southward. However there is also a remarkable concentration of state-rare disjunct species that are either confined to a region almost entirely north of Virginia or range into the Arctic or sub-Arctic. A number of species , while not rare, also have markedly northern distributions. Some of these, as well as a few of the rarer species, have circumpolar or Eurasian ranges. By contrast, characteristically southern species are few here, and only one state-rare species is in this category. Among the state-rare northern species are Carex prairea, C. interior, Juncus brachycephalus, J. nodosus, Menyanthes trifoliata, Spiranthes lucida, Salix discolor , Veronica scutellata and Filipendula rubra. Salix discolor is the rarest of these since, as far as is known, it is confined to this site in Virginia (Ludwig, personal communication, 1996). Parnassia grandifolia is also regarded as very rare to uncommon (Ludwig, 1991). This species is uncommon throughout its range which includes the Southern Appalachians and the Ozarks, with Southern outliers in Florida and Texas. It is verified from ten sites in Virginia at present (Ludwig, personal communication, 1996).

More common species with northern distributions are Campanula aparinoides, Spiranthes cernua, Caltha palustris, Salix eriocephala, Ranunculus carolinianus, Lycopus uniflorus, Bidens frondosa, B. cernua and Mentha arvensis as well as others less closely correlated.

Of the more common species in the state, but with a southern distribution, Agalinis purpurea is very conspicuous in the meadow, while Peltandra virginica is rare at Folly Mills.

In seeking answers to questions posed by the wetland community, attention was drawn to the local setting in terms of geology, topography, ambient chemistry and ice-age influences. Central here is the necessity of satisfying the requirements of the disjunct northern flora as well as that of more southern distribution. Ogle (1982) discussed the formation of "frost pockets" by a combination of topographic features and the common influx of continental polar air masses on the Blue Ridge plateau of Carroll and Grayson Counties in Virginia. His interest was to explain the presence of northern species such as Dalibarda repens and Vaccinium macrocarpon in a number of dominantly acidic glades. These glades are 1000 ft (300 meters) or more higher in elevation than the Folly Mills wetland, although at slightly lower latitude. However the elevated upper watershed and topographic dam at Folly Mills might well be as effective in trapping cold air as the glades. Like streams in the vicinity of the glades, Folly Mills is a northeast-flowing stream, and thus, as suggested by Ogle, is on the receiving end of polar air masses. In any case late-season frost here is a matter of record. It is also likely that the constant influx of cool Calcareous spring water creates salubrious conditions for a variety of plants, including both northern and southern species at Folly Mills (Mueller, 1994). In contrast to the Wetland the adjacent upland forest contains few if any markedly northern species, with the possible exception of Chimaphila umbellata (which occurs with C. maculata) and the uncommon fruticose lichen Cetraria arenaria. However C. umbellata also occurs on the North Carolina piedmont and coastal plain (Radford et al, 1964) and C. arenaria occupies an unusual habitat under Pinus virginiana here. The Southern Appalachian character of this forest is further emphasized by the presence of Quercus stellata and Diospyros virginiana. The wetland appears to be a true relictual refugium.

Once the questions of stability with regard to topography and ambient conditions are resolved there still remains the role of disturbances such as fire and animal impacts. At present the wetland seems stable with respect to both water flows and encroaching woody or other invasive vegetation. The growth of certain of the rare species such as Buckbean is extraordinarily vigorous and this plant may even be expanding its area of occupation. This may in part be a conseqence of it being less palatable to the horses, which are at present the dominant large herbivores. Indeed, the general stability of the vegetation may be a result of the continuous presence of herbivores both in presettlement and post-settlement times. As suggested earlier these considerations should enter into any management plan for this community.

The Folly Mills community is of course vulnerable to a variety of threats to its existence. Beyond management considerations looms possible impending development of its watershed and spring recharge area, which could sap its water supply and introduce degrading chemicals such as herbicides. There is evidence that human impacts have already extirpated many rare plants in the Central Appalachians. An example is the apparent disappearance of Buckbean from certain previously known stations such as the Cranesville Swamp of West Virginia (McDonald, 1993) and Big Meadows in Shenandoah National Park. The continued existence of this wetland is dependent on protection of the watershed that maintains the special hydrologic, climatic and perhaps unknown ecologic conditions.


	FM1		FM2
	0-10cm	10-20cm	0-10cm	10-20cm
pH	7.7	7.6	6.6	7.2
OM%	6.0	2.9	5.5	2.1
SS	128.0	51.0	166.0	26.0
P	2.5	3.0	1.0	1.0
K	12.5	6.5	4.5	11.0
Ca	1200.0	1200.0	1200.0	648.0
Mg	120.0	120.0	120.0	120.0
Zn	6.1	1.7	5.3	0.6
Mn	16.1	16.1	10.9	4.9
Cu	21.3	1.7	11.9	0.6
Fe	833.3	709.1	108.1	83.3
Be	0.4	0.3	0.5	0.2


Table 1: Chemical analyses of the Folly Mills Wetland soils at two sites and depths.
OM=organic matter in percent. Soluable Salts (SS) and all elements are in parts per million. Analyses by Virginia Cooperative Extension Service at Virginia Polytechnic and State University.

Acknowledgments
The investigators are indebted to the following individuals and organization: Elizabeth DeMar Mueller, co-owner of the wetland, for unflagging appreciation of its value and need for protection; Douglas Ogle for his many suggestions and aid in bringing this work to publication; J. Christopher Ludwig for his helpful comments; Gus Mueller for his observations, able word processing and assistance with the manuscript. Dorothy Simpkims for continuous support and Doris True and the Virginia Native Plant Society for their interest, publicity and registration of this rare community.

Literature Cited

Braun, E. Lucy, 1950. Deciduous Forests of Eastern North America. McMillan, New York.

Cronquist, A., 1991. Manual of Vascular Plants of the Northeastern United States and Adjacent Canada, 2nd Edition, The New York Botanical Garden, Bronx, New York.

Crum, Howard and Lewis E. Anderson, 1981. Mosses of Eastern North America in two volumes, Columbia University Press, New York..

Guilday, J. E., 1984. "Pleistocene Extinction and Environmental Change, Case Study of the Appalachians" in P.S Martin and R. G. Klein, eds, Quaternary Extinctions, A Prehsitoric Revolution, University of Arizona Press, Tucson, Az. 223-249.

Hutton , Eugene E. Jr. , Clark Miller and Charles Conrad, 1968. "A Marl Marsh Natural Area in West Virginia." Castanea 33. 241-246.

Ludwig, J. Christopher, 1991. "Large-Leaved Grass-of-Parnassus" in Karen Terwilliger, Coordinator, Virginia's Endangered Species. McDonald and Woodward, Blacksburg, Virginia, 114-115.

Ludwig, J. Christopher, 1995. "Attachment 1: Non-Vascular Plants," Natural Heritage Resources of Virginia: Rare Plants, Natural Heritage Technical Report 95-1, Virginia Division of Natural Heritage, Richmond, Virginia.

Ludwig, J. Christopher, 1996. Natural Heritage Resources of Virginia: Rare Vascular Plant Species. Natural Heritage Technical Report 96-1. Virginia Division of Natural Heritage, Richmond, Virginia.

McDonald, Brian R. 1993. "Rare Plants of the Upland Forests" in Stephenson, Steven L. ed., Upland Forests of West Virginia. McClain Printing Co., Parsons, West Virginia.

Mueller, R.F., 1994. "Central Appalachian Forests, A Guide for Activists." Wild Earth 4 (3) 37-49.

Ogle, Douglas W., 1982. "Glades of the Blue Ridge In Southwestern, Virginia" in Symposium on Wetlands of the Unglaciated Appalachian Region Morgantown, West Virginia University, 143-147.

Ogle, Douglas W. 1989. "Barns Chapel Swamp: An Unusual Arbor-vitæ (Thuja occidentalis L.) Site in Washington County, Virginia." Castanea 54 (3) 200-202.

Rader, E.K., 1967. Geology of Staunton, Churchville, Greenville and Stuarts Draft Quadrangles, Virginia Div. of Mineral Resources, Charlottesville Virginia, 43 pp.

Radford, Albert E. , Harry E. Ahles and C. Ritchie Bell, 1964. Manual of the Vascular Flora of the Carolinas. University of North Carolina Press. Chapel Hill, North Carolina.

Strausbaugh, P.D. and Earl L. Core, 1978. Flora of West Virginia. Second Ed. Seneca Books. Grantsville, West Virginia.

Stuckey, Ronald L. and Guy L. Denny, 1981. "Prairie Fens and Bog Fens in Ohio: Floristic Similarities, Differences, And Geographical Affinities" in Geobotany II 1-33 Robert C. Romans, Ed., Plenum Press, New York.

When citing this paper please refer to Forests of the Central Appalachians Project, Virginians for Wilderness, 1998.