Soil and Biota of Serpentine: A World View 2009 Northeastern Naturalist 16(Special Issue 5):223–252 Serpentine Geoecology of the Eastern and Southeastern Margins of North America Earl B. Alexander* Abstract - Most of the ultramafic rocks from Newfoundland to Alabama, inland from the Atlantic Ocean, and from Arkansas to Texas, inland from the Gulf of Mexico, are peridotites and serpentinites derived from the mantle in oceanic or magmatic-arc settings. They were accreted to a precursor of the North American continent more than 0.25 Ga ago. The serpentine soils range from very cold Entisols and Histosols in Newfoundland and Quebec to cold or cool Inceptisols southward to the limit of late Pleistocene glaciation about latitude 41°N. They are warm to hot Alfisols in the unglaciated areas from New Jersey south to Alabama, with some Mollisols in the Blue Ridge Mountains. Mollisols are the dominant serpentine soils in the drier Llano uplift of Texas. The woody vegetation on the serpentine soils is relatively sparse or stunted, or both. Many of the plant species grow mainly or only on serpentine soils, and some that are common on other soils do not grow on serpentine soils. Some of the species are circumpolar and are common on serpentine soils in both eastern and western North America, and some have distributions that are disjunct from populations on nonserpentine soils of midcontinental prairies. The most distinctive features of serpentine soils are low exchangeable Ca/Mg ratios and high first-transition element concentrations from Cr through Mn, Fe, and Co to Ni. Although some of the serpentine plants have relatively high Ni contents that are toxic to some plants, it is mostly the low Ca/Mg ratios that are responsible for the unique plant assemblages on serpentine soils. The serpentine soils have soil organic matter contents comparable to those of nonserpentine soils. Introduction Ultramafic rocks, which are commonly called serpentine among ecologists, are sparse in eastern North America, but they have distinctive soils and vegetation. The serpentine plants are of special interest to botanists, because many of the plants are rare species or are present only in serpentine habitats. These habitats are seldom placed in a geoecological perspective. Huggett (1995) has presented the concepts and principles of geoecology. Subsequently, Alexander et al. (2007) have addressed serpentine geoecology and characterized serpentine geoecosystems of western North America. This article presents a characterization of the serpentine geoecosystems on the eastern and southeastern margins of the continent. It is provided to aid in the linkage of serpentine habitats to the geology and soils that make them distinctive. The geological and biological aspects are considered to be one integrated system in geoecology. A presentation of the geological framework and other abiotic aspects of geoecosystems is followed by a more integrated *Soils and Geoecology, 1714 Kasba Street, Concord CA 94518; alexandereb@att.net. 224 Northeastern Naturalist Vol. 16, Special Issue 5 presentation of the geological and biological aspects that emphasizes soils and their vegetative cover. Geology Most of the ultramafic rocks of eastern North American are peridotite and serpentinite (hydrothermally altered peridotite) derived from the mantle. These rocks were produced in oceanic or magmatic-arc settings and accreted to a precursor of the North American continent during deformational or mountain building episodes called orogenies. The oldest orogenic episode in which appreciable ultramafic rocks were accreted to ancient North America was the Proterozoic Grenville orogeny that led to the formation of a Neoproterozoic supercontinent called Rhodinia. Rocks of the Grenville orogenic belt, or similar rocks, are present from Labrador through Quebec, Ontario, and the Adirondack and Appalachian Mountains, and on several continents. They are exposed in the Llanos uplift (Fig. 1) and in southern Mexico. The precursor of North America, following the breakup of Rhodinia, has been called Laurentia. It was separated from the continents of Baltica and Gondwana by the Iapetus Ocean. Early in the Proterozoic era, mantle-derived rocks from ocean spreading centers and magmatic arcs were accreted to Laurentia, along with pieces of Laurentia that had rifted away from it upon the breakup of Rhodinia. This event has been called the Taconian orogeny and the accreted terranes are designated Laurentia-Iapetus in Figure 1. During the Taconian and subsequent Paleozoic orogenies, rocks inboard from the accreted terranes were displaced and deformed and they are designated Laurentia in Figure 1. Ganderia, Carolinia, and Avalonia accreted during Figure 1. Tectonically altered terranes of the Appalachian and Ouachitan orogens. The map of the Appalachian orogen in eastern North America follows that of Hibbard et al. (2006). 2009 E.B. Alexander 225 the early to middle Paleozoic Salinian and Acadian orogenies (Eyles and Miall 2007) resemble South American or African components of Gondwana. Meguma, the last piece added to Laurentia, resembles parts of north Africa. Late in the Paleozoic era, Africa closed upon eastern North America in the Alleghanian orogeny and South America closed upon southeastern North America in the Ouachitan orogeny. This aggregation of continents formed Pangea, the last supercontinent, about 0.25 Ga ago. Following the breakup of Pangea early in the Mesozoic era, no exotic terranes have been accreted to eastern North America. Northern Appalachian ultramafic rocks The ultramafic rocks are most abundant in the Laurentia-Iapetus domain, which in the northern Appalachian area has been called the Dunnage domain. These rocks are most concentrated along faults on the western boundary of the Laurentia-Iapetus area (Fig. 1), such as along the Baie Vert- Brompton and Taconic lines (Hatch 1982, Williams and St-Julians 1982) from Newfoundland through southeastern Quebec, Vermont, and western Massachusetts and Connecticut (Fig. 2). Ophiolites with ultramafic components are readily recognized in Newfoundland and Quebec, but deformation and metamorphism make ophiolites more difficult to identify south of the Thetford Mines, Asbestos, and Mount Orford ophiolites in Quebec. The general sizes of ultramafic bodies diminish southward along the Baie Verte- Brompton andTaconic Lines, and the rocks in western New England are characteristically almost completely serpentinized with some talc schist and talc-magnesite or magnesite aureoles. Ultramafic rocks are less abundant in Ganderia and Avalonia than in the Laurentia-Iapetus domain. There are none in Meguma. There are small bodies of ultramafic rocks along the Connecticut Valley-Gaspé trough and on the Bronson anticlinorum in central New England and adjacent Canada (Lyons et al. 1982), on Deer and Little Deer Isles in Penobscot Bay (Wing 1951), and on Boil Mountain and in the Jim Pond formation in western Maine (Boudette 1982, Gerbi et al. 2006). Figure 2. Distributions of ultramafic rocks in the northern Appalachian region. 226 Northeastern Naturalist Vol. 16, Special Issue 5 Southern Appalachian ultramafic rocks Ultramafic rocks of the southern Appalachian orogen, south of the relatively large Baltimore mafic complex in Maryland and southeastern Pennsylvania, are most concentrated along the Brevard fault zone on the eastern margin of the Blue Ridge Mountains and in associated foothills and highlands (Fig. 3). In western North Carolina and northern Georgia, there are many small and lenticular bodies of dunite conforming to the regional rock foliation (Misra and Keller 1978). Serpentinization is evident around the margins of these bodies, and soapstone is common. Alteration of dunite and harzburgite in the lenticular bodies increases toward the northeast, and ultramafic rocks and associates in the Abemarle-Nelson belt of Virginia are mainly amphibole-chlorite schist, serpentinite, soapstone, and other altered peridotite. The Abemarle-Nelson is a belt <1 km wide with several narrow bands <2 km to >20 km long in the foothills of the Blue Ridge Mountains, parallel to the inner margin of the Piedmont. Small lenses of altered Laurentia-Iapetus domain ultramafic rocks occur throughout the inner Piedmont (Misra and Keller 1978), which is separated from Carolinia on the outer Piedmont by the Central Piedmont shear zone (Hibbard et al. 2006). Several elongated ultramafic bodies up to 2 km wide are scattered across the Outer Piedmont, where they are less common than on the Inner Piedmont. The relatively large Hammett Grove suite along the edge of the King Mountain belt, near the Central Piedmont shear zone, may represent an ophiolite in which the ultramafic rocks have been metamorphically altered to soapstone and serpentinite (Mittwede 1989). It is exposed for about 11 km along the strike, with a common width of 200 to 300 m and a maximum width of 1 km (Butler 1989). Iredell soils (Hapludalfs with “mixed” mineralogy) were mapped on metapyroxenite and metagabbro of the Hammet Grove suite (Jones 1962, Mittwede 1989). Ultramafic rocks of the Charlotte and King Mountain belts along the Central Piedmont shear zone are mainly minor constituents of mafic intrusive complexes that are generally located near faults (Butler 1989). Figure 3. Physiographic units and distributions of ultramafic rocks in the southern Appalachian region. Rock locations and designations after Larabee (1966). 2009 E.B. Alexander 227 The largest southern Appalachian exposures of ultramafic rocks are in the Baltimore mafic complex. Ultramafic rocks of the Baltimore mafic complex are in a basal unit of serpentinized dunite (forsterite olivine) and chromitite and in an overlying gabbroic unit approximately 5 km thick that contains many cumulus peridotite layers (Hanan and Sinha 1989). Rocks of the Baltimore mafic complex are mainly in three large blocks from southeastern Pennsylvania to near Baltimore in Maryland. Also, lenses and pods of the ultramafic Soldiers Delight belt occur in the Wissahickon formation. Ouachitan area (Arkansas to Texas and Chihuahua) Late Proterozoic rifting opened an ocean along the edge of Laurentia that is now the southeastern margin of the North American craton. Marine sediments were deposited along this edge of the craton until the late Paleozoic Era. Then sediments were thrust over the margin of the craton during the Ouachitan orogeny, which was contemporaneous with the Alleghanian orogeny. Small rootless pods of ultramafic rocks are scattered through the Paron Nappe of the Benton uplift in the Ouachita Mountains, and the effects of Ouachitan orogenic activity are evident in the Arbuckle and Wichita Mountains of Oklahoma and the Llano and Marathon uplifts in Texas (Fig. 1). Ultramafic rocks are reported from the Llano uplift, but in Grenville basement, rather than in Paleozoic strata. Proterozoic rocks of the Grenville realm, which are widely exposed in Labrador and southeastern Canada, appear in central and western Texas and in Mexico (Mosher 1998). The ultramafic body in the Llano uplift is serpentinized peridotite, or serpentinite, that was accreted to Laurentia about 1.2 to 1.3 Ga ago. It is about 6 km long and 0.5 to 2 km wide, as reported by Garrison (1981). The serpentinite is lizardite with accessory magnetite; relict minerals are sparse. Physiography The ups and downs of the Appalachian orogen were recorded by Paleozoic sediments. When the Appalachians were high, sediments were spread across the Appalachian Plateau west of the mountains and across contiguous or adjacent areas in Europe and Africa. When the Appalachians were low, sediments were deposited in basins within the area of the orogen and in the adjacent ocean. Toward the end of the Paleozoic Era, rifting produced basins that were then filled with Triassic sediments and volcanics. The Connecticut Valley in central New England and the Bay of Fundy between New Brunswick and Nova Scotia are remnants of two of these basins. The Palisades sill in the Trenten basin is a layered body with an olivine-rich layer that is ultramafic (Gorring and Naslund 1995), but any exposures of it are too small to warrant the interests of pedologists or ecologists. Mountains of the Appalachian are generally highest near the northwest margin of the orogen and decrease in elevation toward the Atlantic coastal plain. The White Mountains in New England are exceptions; they are the highest in the northern Appalachians. The southeastern margin of the Appalachian orogen is obscured by the Atlantic coastal plain. 228 Northeastern Naturalist Vol. 16, Special Issue 5 Northern Appalachian physiography On the northwest margin of the Appalachian orogen, the Notre Dame Mountains of Gaspésie and the Long Range Mountains in Newfoundland rise abruptly above the St. Lawrence lowland and the Gulf of St. Lawrence. From that margin, the topographic highs are represented by one or more planes that slope southeast to the Atlantic coastal plain, which is offshore of Newfoundland and Nova Scotia. Some geologists have suggested that the summits that represent these planes are remnants of ancient peneplains. South from the Notre Dame Mountains, the western margin of the northern Appalachians is bound by low valleys. These are the Champlain Valley west of the Green Mountains and the Hudson Valley west of the Taconic Mountains. The highest summits of New England are in the White Mountains of New Hampshire (Mount Washington, 1889 m; Fig. 2) and in Maine (Mount Katahdin, 1580 m), rather than in the Green and Taconic Mountains (Denny 1982). A massive delta west of the Taconic Mountains, the Catskill delta, was produced from Appalachian sediments after Acadian uplift. All of the northern Appalachians, south to Long Island, were covered by ice during the last major glaciation, although there may have been some unglaciated nunataks on Newfoundland and the Gaspé Peninsula. For sometime after the Laurentide continental glacier had melted, icecaps persisted on Newfoundland and the Gaspé Peninsula. Ice cover slowly disappeared from the Gaspé Peninsula between 10 and 13.5 ka ago. Permafrost is still present above about 1200 m on Mont Jacques-Cartier (1270 m), but the active layer above the permafrost is about 6 m deep (Gray and Brown 1979). Southern Appalachian physiography The highest parts of the southern Appalachians are in the Blue Ridge Mountains (Fig. 3) in North Carolina (Mitchell Mountain, 2037 m) and highs diminish both southward and northward (Hack 1982). The highest mountains in northern Virginia, Maryland, and Pennsylvania are in the Valley and Ridge, rather than in the Blue Ridge Mountains. As in the northern Appalachians, the topographic highs are represented by one or more planes that slope southeast to the Atlantic coastal plain. In the southern Appalachian, however, there are two abrupt drops in the northwest–southeast topographic trend. One is at the transition from the Blue Ridge Mountains and associated foothills and highlands near the Brevard zone to the much lower, undulating to hilly Piedmont, and the other is at the Fall Line from the Piedmont to the Post-Paleozoic sedimentary cover on the Atlantic coastal plain. Ouachitan Orogen The Ouachita, Arbuckle, and Wichita Mountains have high relief, but relatively low altitude. The highest mountains in these areas are Magazine Mountain (839 m) in the Ouachita Mountains and Mt. Marcy (713 m) in the Wichita Mountains. Relief is low in the Llano uplift area. 2009 E.B. Alexander 229 Climate Climates of the Appalachian Mountains are continental, because prevailing west winds minimize the ameliorating effects of the Atlantic Ocean. The mean annual temperature ranges from -5 to 20 °C (Fig. 4A). The frost-free Figure 4. A. Mean monthly temperature. B. Mean monthly precipitation. Station locations (name and state or province, latitude, longitude, altitude): Bal (Baltimore, MD, 39.18°N, 76.76°W, 45 m), Ban (Bangor, ME, 44.80°N, 76.76°W, 107 m), Cow (Coweeta, NC, 35.53°N, 83.43°W, 682 m), Lla (Llano, TX, 30.75°N, 98.68°W, 317 m), and Tre (Trepassey, NL, Canada, 45.57°N, 52.72°W, 128 m). 230 Northeastern Naturalist Vol. 16, Special Issue 5 season is about 3 or 4 months in the north to 7 months in the south and 7 or 8 months in the area of the Ouachitan orogen. Mean annual precipitation is mostly in the 75 to 150 cm range, but up to about 200 cm at the higher elevations in the southern Appalachian Mountains (Fig. 4B). It decreases westward to about 60 cm in the Llano area and less in the Marathon area. Summer temperatures are cool in Newfoundland to hot at the lower elevations in the southern Appalachian and in western areas. The winter precipitation is mostly snow in the northern Appalachian region and at high elevations and rain or snow at lower elevations in the southern Appalachian and in western areas. Assuming that the rate of evapotranspiration is about 2 to 3 cm/month for each degree Celsius during summers, there is a severe water deficit at Llano, TX, during the months of July and August. Drought is expected in the Appalachian area only on shallow soils. Hydrology Streams of the Appalachian region flow throughout the year. Only small headwaters become dry during summers. Streams originating in the Llano and Marathon uplift areas become dry during summers, but the Colorado River flows through the Llano uplift all through the year. In the Appalachian region, maximum stream flows are in the spring, when ice and snow are melting most rapidly. Flow in the Penobscot River of Maine peaks in April, after the streams in the southern Appalachian have peaked in March (Fig. 5). Cleaves et al. (1974) have monitored the water chemistry of a small stream in the Soldiers Delight serpentine area of Maryland. They sampled four times a year for a year. The mass of dissolved constituents in stream discharge exceeded that of particulate losses from the small serpentine watershed. Watershed losses dissolved in stream water were dominated by bicarbonate (HCO3 1-), magnesium (Mg2+), and silica (presumably silicic acid, H4SiO4). Cleaves et al. (1974) compared the stream losses to those from a small felsic schist watershed. The total concentration of dissolved constituents was much lower in the nonserpentine watershed and the cations were present in different proportions (Table 1). Whereas Mg2+ was the dominant cation in water from the serpentine watershed, Na+ was the predominant cation in water from the felsic schist watershed. In contrast to the usual bicarbonate waters of streams, travertine (CaCO3) is deposited from very strongly alkaline spring water and seeps in some Table 1. Mean concentrations of anions, cations, and silicon as silica in base flow from a serpentine watershed at Soldiers Delight and a similar felsic schist watershed (Cleaves et al. 1974). - = not determined. AnionsA CationsA Silica Bedrock HCO3 1- NO3 1- Cl1- SO4 2- Ca2+ Mg2+ Na+ K+ (SiO2)A Serpentine 2.02 0.02 0.09 0.47 0.15 2.49 0.10 0.005 20.0 Felsic schist 0.13 - 0.06 0.03 0.07 0.06 0.15 0.02 9.3 A Anions and cations measured in mmol/L; silica measured in mg/L. 2009 E.B. Alexander 231 serpentine areas of Newfoundland (Roberts 1992). The genesis of travertinegenerating Ca(OH)2 spring waters from peridotite is described by Alexander et al. (2007). Soils and Vegetation Many different kinds of soils occur from the northeast end of the Appalachian region in Newfoundland to the southwest end in Alabama. The serpentine soils differ from nonserpentine soils in morphology, mineralogy, and chemistry. It is the chemistry of the soils inherited from their serpentine parent materials that has the greatest influences on vegetative cover and plant species differences from serpentine and nonserpentine soils. The vegetative cover is generally less massive and the tree canopy more open on serpentine soils than on adjacent nonserpentine soils. Also, serpentine soils have different assemblages of plant species than other kinds of soils. Appendix 1 lists the taxonomic names including authorities and the common names of plant species mentioned herein. The serpentine soils from north to south have cryic (very cold), frigid (cold), mesic (cool to warm), and thermic (hot) temperature regimes (Soil Survey Staff 1999). Serpentine soils of the Appalachian region have udic (moist) soil moisture regimes, with aquic conditions common in Newfoundland and on the Gaspé Peninsula. The soils of the Llano uplift have ustic (seasonally dry, but with a warm, moist period) soil moisture regimes. Figure 5. Mean monthly discharge (calculated as the volume divided by the watershed area) from rivers in the Appalachian Orogen and through the Llano uplift. Stream names and gaging stations: Lla (Colorado River, Wharton, TX), Pen (Penobscot River, New Enfield, ME), Pot (Potomac River, Washington, DC), and Roa (Roanoke River, Roanoke Rapids, NC). 232 Northeastern Naturalist Vol. 16, Special Issue 5 Weathering, leaching of basic cations and silica, and the oxidation of iron are major soil-forming processes in the freely drained serpentine soils. Smectites are produced where silica and magnesia accumulate and, in soils of the southern Appalachian, interlayered chlorite-vermiculite minerals are common. In well-drained soils of the northern Appalachian, podzolization is a major soil-forming process, but only in nonserpentine soils. In both serpentine and nonserpentine soils of the southern Appalachian, incorporation of organic matter as humus into surface A horizons and accumulation of clay in argillic or kandic B horizons are major soil-forming processes. Because Spodosols (Podozols; FAO/ISRIC/ISSS 1998) do not develop in serpentine materials, except where they have a cover of nonserpentine materials, the more developed serpentine soils in the northern Appalachian are Inceptisols (Cambisols and Umbrisols). Alfisols and Ultisols (Luvisols, Lixisols, and Acrisols) prevail as the more-developed soils of the southern Appalachian region (Table 2). Another factor is the Pleistocene glaciation that covered the northern Appalachian south to northern New Jersey. Soils in the southern Appalachian are beyond the limit of continental glaciation, consequently many of them are much older than any in the northern Appalachian region. Reed (1986) has descriptions of most of the major serpentine localities in eastern North America, including pipes and dikes of ultramafic rocks from the mantle of Earth that are present west of the Appalachian Mountains from Canada to Arkansas. Northern Appalachian glaciated area Ultramafic rocks are more concentrated in Newfoundland than in any other Appalachian area (Fig. 2). These rocks are mostly in ophiolites that occupy about 3% (0.3 Mha) of the land in Newfoundland (Roberts 1992). The serpentine soils and plants on the Mount Albert plateau of the Gaspé Peninsula are similar to those in Newfoundland (Sirois and Grandtner 1992). Most of these soils have sandy loam and loam textures and are affected by cryoturbation. Sorted polygons and stone stripes are common. The two main serpentine soils on Newfoundland, which are mostly in glacial drift and colluvium, are the Roundhill Series of well-drained Orthic Table 2. The most-developed and common well-drained soils of soil temperature and moisture regimes in eastern and southeastern North America. Some of the serpentine soils are not common where peridotite and serpentinite are not common soil parent materials. Soil Soil Late Nonserpentine Serpentine temperature moisture Pleistocene Diagnostic Diagnostic regime regime glaciation Soil order horizon Soil order horizon Cryic Udic Yes Podzols Spodic Entisols or None or Inceptisols Cambic Frigid Udic Yes Podzols Spodic Inceptisols Cambic Mesic Udic Yes Inceptisols Cambic Inceptisols Cambic No Alfisols Argillic Alfisols Argillic Thermic Udic No Ultisols Kandic Alfisols Kandic Ustic no Alfisols argillic Mollisols Mollic 2009 E.B. Alexander 233 Regosols (Soil Classification Working Group 1998) on slopes and the Blomidon Series of somewhat poorly drained Gleyed Regosols on bottom land (Table 3; Roberts 1980, 1992). According to the USDA's soil taxonomy, the soils are Orthents and Aquolls (Soil Survey Staff 1999). The soil reactions are neutral (near pH 7), although some organic layers are more acid (pH < 6.5). Roberts (1992) found that some of the Caryophyllaceae (Arenaria humifusa [Low Sandwort] and A. marcesens [Serpentine Stitchwort], and marginally Lychnis alpina [Red Alpine Campion]) and Asteraceae (Solidago hispida [Hairy Goldenrod] and Senecio pauperculus [Balsam Ragweed]) were nickel hyperaccumulators. He found that Ni availability increased as the soil pH decreased. In the vicinity of Table Mountain in the Long Range Mountains of western Newfoundland, Dearden (1979) described several plant communities from scarps and from talus at the bases of scarps across patterned ground to fens and meadows. He noted the marked contrast from fir-spruce forests common on Newfoundland to the relatively barren serpentine landscapes. Adiantum aleuticum (Maidenhair Fern) prevails in rock crevices at the bases of the scarps. Some of the scarps that are below the 712-m summit of Table Mountain have foot-of-scarp soils with relatively high Ca/Mg ratios and alkaline reaction (pH 8) that might be traced to the seepage of water from serpentinized peridotite, although Dearden did not mention this linkage. The alkaline soils support small Larix laricina (Tamarack) trees and Juniperus communis (Dwarf Juniper) and J. horizontalis (Creeping Juniper) shrubs. Stone stripes and polygon borders are colonized first by Rhacomitrium lanuginosum (Hoary Rock Moss), followed by Rhododendron lapponicum (Lapland Rosebay), several species of Salix spp. (willow), and herbs in the pink family (Caryophyllaceae). The non-stony polygon centers are colonized by chamaephytes such as Silene acaulis (Moss Campion), Armeria labradorica (Thrift), Diapensia lapponica (Pincushion), and Saxafraga oppositifolia (Saxifrage). The wetter polygons are colonized by cespitose Scirpus sp. (Bulrush), Carex echinata (Star Sedge), and Juncus trifidis (Highland Rush). The mosses are Pleurozium schreberi (Big Redstem Moss), Hylocomiun splendens (Feather Moss), and Dicranum bonjeanii (Bonjean’s Dicranum Moss). Small depressions may have Andromeda polifolia var. glaucophylla (Bog Rosemary), Myrica gale (Sweet Gale), and J. horizontalis shrubs, also. Isolated hummocks are colonized by Alnus crispa (Scrub Alder), followed by other dwarf tree species. Banks at the edges of solifluction terraces are colonized by prostrate tree species such as Betula pumila (Bog Birch), Salix arctica (Arctic Willow), and shrubs, including Vaccinium uliginosum (Alpine Blueberry), Potentilla fruticosa (Cinquifoil), and J. communis. Organic soils in the fens are generally very thick (depth >2 m) and acid (pH <6). They are dominated by Carex spp. (sedges), with Festuca rubra (Red Fescue), Eriophorum spp. (cotton-grass), and Juncus spp. (rushes). The wet meadows are also dominated by many species of Cyperaceae. Two plant species, Yellow Lady’s Slipper (Cypripedium calceolus) and Mountain-avens (Dryas integrifolia), were found on Newfoundland only in 234 Northeastern Naturalist Vol. 16, Special Issue 5 Table 3. Some properties of subsoil horizons and organic carbon in the upper meter of soil. State or Lat. Sub Munsell color Clay Fed B Exch. Ca/Mg Org. carbonC (kg/m2) Sand or silt Soil Province (°N) hor. (moist) TextureA (g/kg) (g/kg) (mol/mol) pH 0.5 m 1.0 m mineralsE Roundhill, Orthent Nfl49.2 C 2.5Y 5/4 GrL 195 - 0.09 7.0 2.7 - - Blomidon, Aquoll Nfl49.2 Cg 2.5Y 3/2 loam 256 - 0.05 7.0 11.0 - - Dystric Eutrudept NJ 40.7 Bw 7.5YR 4/4 vStSiL 77 - 0.15 7.7 5.5 - Ser, Tal Aquic Hapludalf MD 39.1 Bt 10YR 5/4 SiL - 43 0.06 - 5.5 - Chl, Ser, Ver Typic Hapludalf MD 39.4 Bt 10YR 5/4 SiCL - 60 0.03 - 5.2 6.3 Ser, Chl Lithic Hapludalf MD 39.6 Bt 10YR 5/6 SiL - 36 0.02 - 5.7D - Ser Typic Hapludalf MD 39.7 Bt 10YR 5/4 SiL - 53 0.02 - 4.2 6.4 Ser, Chl Typic Hapludulf 1 NC 35.1 Bt 7.5YR 5/8 CL 343 66 0.03 6.1 4.3 5.8 Act, Chl Typic Hapludalf 2 NC 35.1 Bt 5YR 4/6 clay 553 225 0.09 5.9 6.4 9.8 Tre, Chl Typic Hapludalf 3F SC 34.1 Bt 10YR 3/1 clay 421 17 0.30 5.1 4.2 - Pyr, Qz, Hor Ellijay, Kanhapludalt NC 35.4 Bt 10R 3/6 clay 526 208 0.02 5.4 7.0 9.8 Qz, Pyr, Mic ATexture symbols: CL = clay loam, GrL = gravelly loam, SiL = silt loam, SiCL = silty clay loam, vStSiL = very stony silt loam. BFed: iron (Fe) in citrate-dithionite extract; it is higher in the BC horizons of some of the soils than in Bt horizons that are shown. CSoil organic carbon, SOC, some pedons that lack 0–1.0 m SOC values are deep but lacked SOC data for the 50–100 cm depth. DSOC to the 43 cm depth. EDominant minerals in BC, C, or R horizons: Act = actinolite, Chl = chlorite, Hor = hornblende, Mic = mica, Pyr = pyroxene, Qz = quartz, Ser = serpentine, Tal = talc, Tre = tremolite, Ver = vermiculite. FSimilar to Iredell soils, not a serpentine soil. 2009 E.B. Alexander 235 areas with travertine (Bouchard et al. 1978). This travertine is the same as that reported by Roberts (1992). Both Dearden (1979) and Roberts (1992) reported the dominance of kaolinite in clay fractions of drained soils and smectite in poorly drained soils, but they did not show data to verify the presence of kaolinite, rather than serpentine minerals. De Kimpe and Zizka (1973) found that serpentinized dunite containing serpentine, brucite, and magnetite weathered by way of interstratified minerals to produce chlorite and smectite in an Orthic Melanic Brunisol (Eutrocryept) at Asbestos, Québec. De Kimpe et al. (1987) found that all primary minerals in pyroxenites at Mont Saint-Bruno, PQ, weathered to produce smectites. Sirois and Grandtner (1992) related the serpentine soils and plant communities on the Mount Albert plateau (Fig. 6) to slope characteristics and drainage. As in Newfoundland, the initial pioneer community is Rhacomitrium lanuginosum (Hoary Rock Moss). Betula glandulosa (Dwarf Birch), Vaccinium uliginosum (Alpine Blueberry), and Rhododendron lapponicum (Lapland Rosebay) are characteristic shrubs. Apparently Cetraria laevigata (Striped Iceland Lichen) replaces the moss as the shrub layer develops. Soils on well-drained sites develop from Cryic Regosols to Orthic Humic Regosols and Eutric Brunisols. The well-drained Mollisols on amphibolite of the plateau are Dystric Brunisols. The krumholz soils are Orthic or Gleyed Ferro-Humic Podzols with Picea mariana (Black Spruce) on serpentine and with Abies balsamifera (Balsam Fir) on sites less exposed to wind and on amphibolite. The Podzols on serpentine are not Spodosols, because they lack albic E horizons. Soils on poorly drained sites are Orthic Humic Gleysols, commonly with Ledum groenlandicum (Labrador Tea) plant communities containing much sedge, grass, and bulrush, or with Selaginella selaginoides Figure 6. Mont Albert plateau, PQ, Canada, an all-peridotite landscape southward from an amphibole ridge on the northern margin of the plateau. 236 Northeastern Naturalist Vol. 16, Special Issue 5 (Club Moss). Very poorly drained soils are Rego Gleysols and organic soils with bulrush-moss plant communities. The bulrush-moss communities are dominated by Scirpus sp. (Cespitose Bulrush) and either Campylium stellatum (Campylium Moss) or Sphagnum spp. The former contains Labrador Tea and Andromeda polifolia var. glaucophylla (Bog Rosemary) and the latter bulrush-moss community contains Vaccinium oxycoccus (Small Cranberry), Drosera rotundifolia (Roundleaf Sundew) , and Smilacina trifolia (Twisted-stalk). Organic soils, which are not extensive on the Mount Albert plateau, are predominantly Terric Humisols (Terric Cryosaprists). Some of the Histosols are in small mounds, or hummocks, among Histic Cryaquolls. Ultramafic rocks do not appear to be very favorable substrates for saxicolous lichens, but some are found exclusively on serpentine rocks or nearby amphibolite exposures on the Gaspé Peninsula (Sirois et al. 1988). Asbestos mine wastes in the Thetford Mines area are unfavorable substrates for all vascular plants. Even after adding fertilizer and organic amendments, Moore and Zimmerman (1977) found critically low N and Ca concentrations in plants grown on the wastes. No published reports of serpentine soils in New England were found. Much of the serpentine is covered by glacial drift and lacks distinctively serpentine vegetation. Zika and Dann (1985) listed some plants that are characteristic of serpentine habitats from Québec through New England to Pennsylvania. They are Asplenium trichomanes (Maidenhair Spleenwort), Campanula rotundifolia (Bluebell Bellflower), Cerastium arvense (Chickweed), Deschampsia caespitosa (Tufted Hairgrass), and D. flexuosa (Wavy Hairgrass). Arenaria macrophylla (Largeleaf Sandwort) and Adiantum aleuticum (Maidenhair Fern) are ubiquitous on rocky dunite outcrops in Vermont. Rajakaruna et al. (2009) have summarized the current knowledge of serpentine plant distributions in the northern Appalachian area, and Harris et al. (2007) compiled a lichen species list for the Pine Hill exposure of serpentinized peridotite on Little Deer Isle, ME. Characteristic soils of the Pine Hill body, which is a clinopyroxene-rich peridotite that is about 60% altered to serpentine, are very shallow Entisols and shallow Inceptisols. The plant cover ranges from bare rock and grass (mainly Danthonia spicata [Poverty Oatgrass], Deschampsia.flexuosa, and Festuca filiformis [Fineleaf Sheep Fescue]) on the summit of Pine Hill to a White Spruce-White Cedar/ Dwarf Juniper-Bayberry plant community on side slopes that lack glacial drift (Fig. 7). A serpentine body on Deer Isle is dunite and harzburgite, with serpentinite on the margin where blocks were quarried until it was decided that rock fracturing was too great for a commericial operation. Northern Piedmont Highlands On Staten Island, NY, Parisio (1981) described and sampled a soil on serpentinite in a small hilly driftless area between Wisconson moraines and Cretaceous sedimentary rocks of the Atlantic coastal plain. It had a brown (7.5YR 4/4), very stony loam cambic horizon with only 8% clay and an exchangeable Ca/Mg ratio of 0.15 mol/mol (Table 3). The pH was 7.7 in 2009 E.B. Alexander 237 distilled water and 6.2 in KCl solution. Serpentine and smectite are the main clay minerals, with some talc, mica, and goethite. Quartz and feldspar were found in very fine sand from the solum, but not in the parent rock. The soil is a Eutrudept (Eutric Cambisol). It has a mesic soil temperature regime. The plant community was a Andropogon scoparius (Little Bluestem) prairie, with predominantly the grass Smilax rotundifolia (Roundleaf Greenbrier) and Rubus allegheniensis (Blackberry). The serpentine vegetation of the Nottingham barrens in southwestern Pennsylvania and the Soldiers Delight barrens in Maryland (Fig. 8), both on ultramafic rocks of the Baltimore complex, are the most thoroughly studied serpentine areas of the Appalachian region. The term “barrens” has been used for treeless prairies or savannas in otherwise forested parts of eastern North America (Tyndall 1994). They have relatively good grass and forb cover, compared to the “barrens” of western North America. Serpentine soils of the Baltimore complex have been mapped in the moderately deep Chrome (Typic Hapludalfs), very deep Aldino (Typic Fragiudalfs), and deep Conowingo (Aquic Hapludalfs) and Calvert (Typic Fragiaqualfs) series. About 1700 ha of the Chrome and 750 ha of the Conowingo soil have been mapped in Chester and Delaware counties, PA, and about 2750 ha of the Chrome and 245 ha of the Conowingo soils in Baltimore, Cecil, Harford, Howard, and Montgomery counties, MD. The area of very deep Aldino soils is greater than that of the Chrome and Conowingo soils, but the Aldino soils were mapped on gabbro as well as on serpentine, and much loess added to the Aldino and Calvert soils has given them properties atypical of serpentine soils (Rabenhorst and Foss 1981). Rabenhorst et al. (1982) studied four pedons of Lithic, Typic, and Aquic Haploxeralfs (Luvisols) on serpentine of the Baltimore complex. Some nonserpentine loess had been incorporated into the soils, mainly in the surface soils where exchangeable Ca/Mg ratios were 0.8 or more in three of the soils, but ratios <0.1 prevailed in the subsoils (Table 3). Soil textures were silt loam in the surfaces and silt loam or silty clay loam in subsoils. Whereas pH Figure 7. Pine Hill, ME. A. Scrubby side slope. B. Grassy summit. 238 Northeastern Naturalist Vol. 16, Special Issue 5 values generally decrease with depth in nonserpentine soils of the northern Piedmont, those in the serpentine soils increased with depth to pH 6.6 to 6.8 in subsoils. Serpentine minerals were present in the coarse clay and silt fractions, but absent from the fine clay <200 nm. Smectites dominated the clay fractions, and chlorite was interstratified with smectite and vermiculite. Soils on serpentinite of a small Soldiers Delight watershed are moderately deep to shallow and lack saprolite that is common over bedrock of igneous and metamorphic rocks in this part of the northern Piedmont (Cleaves et al. 1974). Most of the silicon and magnesium from the weathering of serpentine is leached from the soils, with relatively small amounts of these elements forming smectites and with minor amounts of silica precipitated in the weathered bedrock to form silica boxwork. Chemical denudation exceeds particulate losses from the serpentinite watershed (Cleaves et al. 1974). Harris et al. (1984) found talc in saprolite weathered from a metamorphosed ultramafic rock in the Piedmont. The talc resisted weathering sufficiently to appear in the solum of the soil, which is a very deep Hapludult (Acrisol), above the saprolite. A century or more ago, the serpentine areas of the northern Piedmont were prairies with trees only in ravines and riparian areas. The dominant grasses were Little Bluestem, Aristida purpurascens (Threeawn), Sporobolus heterolepis (Prairie Dropseed), and Sorghastrum nutans (Indian Grass); the main trees were Quercus marilandica (Blackjack Oak) and Q. stellata (Post Oak); Smilax rotundifolia (Roundleaf Greenbriar) was a common shrub or vine; and common serpentinophile forbs were Cerastium arvense and Aster depauperatus (Serpentine Aster). Following the cessation of burning and grazing, the prairies have been invaded by Pinus virginiana (Virginia Pine) and Juniperus virginiana (Virginia Juniper) (Fig. 8), plus Pinus rigida (Pitch Pine) northeast of the Susquehanna River. Some of the serpentine areas are currently managed for the preservation of scarce serpentinocoles (Tyndall 1992) such as Agalinis acuta (Gerardia), Talinum teretifolium (Flameflower), and Linum sulcatum (Flax). According to Reed (1986), Selaginella rupestris (Spike-moss), T. teretifolium, and Phlox sublata (Moss Phlox) are good serpentine indicator plants on the Baltimore complex, but he has reported collecting them on nonserpentine soils further south. The main effects of pine trees on the Chrome soils are increased Ohorizon thickness, lower surface soil pH, and decreased exchangeable Mg, resulting in increased Ca/Mg ratios (Barton and Wallenstein 1997). Increased soil depth was reported, but the pine trees may have become established in deeper pockets of soil, or in less stony soils where the depth measuring rod would be more likely to measure depth to bedrock rather than to a stone above bedrock. Also, increased plant detritus under the trees could cause an apparent increase in soil depth if O-horizons are included in the soil depth. The availability of K and several other plant nutrient elements increase in at least the organic surface horizons following pine invasion, making the soils more favorable for the invasion of other plant species on the serpentine soils (Hochman 2001). 2009 E.B. Alexander 239 It was once commonly thought that the availability of soil water was the main factor limiting plant diversity and growth on the serpentine soils. Hull and Wood (1984) measured summer soil water and oak tree xylem potentials. They concluded that the availability of water does not appear to be the factor allowing Blackjack and Post Oaks to replace Quercus alba (White Oak) and Q. velutina (Black Oak) on serpentine soils. The consensus has shifted toward the Ca/Mg ratio as being a major factor controlling which plants will grow on serpentine soils. Terlizza and Karlander (1979) collected algae from serpentine soils at Soldiers Delight. The algae were found to be Cyanophyta (some of which fix nitrogen), Chlorophyta, and Chrysophyta. At this level of classification, the soil algae composition is similar to that of nonserpentine soils. Panaccione et al. (2001) found lower ectomycorrhizal fungi diversity on serpentine plots at Soldiers Delight than on nearby nonserpentine soils. They collected Cenococcum geophilum Fr. isolates from Virginia Pine seedlings in both serpentine and nonserpentine soils and found that the C. geophilum isolates from serpentine sites were genetically more similar to each other than to isolates from local or distant nonserpentine sites. A beetle (Diabrotica cristata Harris) that is seldom found along the Atlantic coast, but is common further west, was found to be abundant on the Goat Hill and Nottingham barrens and present at Soldiers Delight (Wheeler 1988). The main host plant for the larvae, which are called rootworms, is Andropogon gerardii (Big Bluestem) in the Midwest and assumed to be Little Bluestem on serpentine prairies and savannas of the Baltimore complex. Figure 8. Serpentine savanna at Soldiers Delight, MD. 240 Northeastern Naturalist Vol. 16, Special Issue 5 Blue Ridge Mountains and Southern Piedmont Small areas of residual serpentine soils 15 m deep, or deeper, derived mainly from peridotite and dunite, are present in the Blue Ridge Mountains (Worthington 1964). Very deep, strongly weathered soils are present on the Piedmont as far north as Staten Island, also, but they are not as deeply weathered as those in the Blue Ridge Mountains. Weathering and leaching removed most of the Mg and much of the Si from the old ultramafic parent materials and Cr, Fe, Co, and Ni were concentrated 5- to 7-fold in the soils (Worthington 1964). Analyses of soapstone from Abemarle and Fairfax counties, VA, and very deep soils in it, show that most of the Mg and much of the Si have been lost by weathering and leaching, leaving soils that are about one-third Al- and Fe-oxides (Merrill 1906). This soapstone is metamorphosed peridotite, or pyroxenite, and is composed of talc and chlorite, with inclusions of tremolite. Only one serpentine soil series has been established on the small serpentine exposures of the Blue Ridge Mountains. It is a very deep soil in the Ellijay series of fine, ferruginous, mesic Rhodic Kanhapudalfs (Acrisols). About 250 ha of the Ellijay soils have been mapped on peridotite, mainly dunite, in Jackson County, NC. Major features of Rhodic Kanhapludalfs are a kandic horizon and red colors (hues 2.5YR, or redder, and moist values = 3 or less and dry = 4 or less). A kandic horizon is a horizon of clay concentration, like an argillic horizon, except that the kandic horizon has low cation-exchange capacity (CEC < 160 mmol+/kg of clay at pH 7). At the type locality for the Ellijay series, there is 9.8 kg of OC in the upper meter of soil (pedon S85NC-099-004; Table 3). Radford (1948) described seven plant communities on dunite and serpentinized harzburgite at nine sites in North Carolina and one site in Georgia. He did not describe the soils. A Pine-Bluestem community was the most distinctively serpentine one—the others were similar to plant communities on other kinds of rocks. In the Pine-Bluestem community, Virginia Pine and Pitch Pine were the dominant trees, with subdominant Post Oak and Q. falcata (Southern Red Oak). Ceanothus americanus (Jersey Tealeaf), Vaccinium stamineum (Deerberry), Rhododendron calendulaceum (Azalea). and Mountain Laurel (Kalmia latifolia) were common shrubs, and Big and Little Bluestem and Panic Grass (Panicum spp.) were the most common grasses. Ogg and Smith (1993) studied two deep soils from the Blue Ridge Mountains in North Carolina derived from altered peridotites containing tremolite, or actinolite, and chlorite, with no olivine, and a moderately deep soil from the Piedmont in South Carolina derived from a hornblende-bearing pyroxenite. The soils are Hapludalfs (Table 3). The main clay minerals were found to be interstratified chlorite-vermiculite, kaolinite, and talc in the North Carolina soils and smectite and kaolinite in the South Carolina soil. Goethite is the main iron-oxide mineral. Serpentine soils with vegetation that is the most distinctively different from that on other kinds of soils in the Blue Ridge Mountains are not deep, according to Mansberg and Wentworth (1984). They described a Pitch 2009 E.B. Alexander 241 Pine plant community on the Buck Creek (or Nantahala) ultramafic in Clay County, NC. Sparse, but ubiquitous saplings and understory trees were Tsuga canadensis (Hemlock), White Oak, Acer rubrum (Red Maple), Sassafras albidum (Sassafras), and Amelanchier arborea (Serviceberry). The most common and ubiquitous shrubs were Viburnum cassinoides (Wild-raisin), Deerberry, Physocarpus opulifolius (Ninebark), and Smilax glauca (Cat Greenbrier). The most common forb was Senicio plattensis (now Packera plattensis; Prairie Groundsel), and Big and Little Bluestem were ubiquitous grasses. Prairie Groundsel and Sporobolus heterolepis (Prairie Dropseed) were noted because of their disjunct distributions from midcontinental prairies to serpentine soils of the Appalachian. No specifically serpentine soils were mapped on the Nantahala (Buck Creek) ultramafic in the Soil Survey of Clay County (Thomas 1998). Subsequently, three serpentine soils presumed to represent the dominant ones in the Nantahala area were described and sampled (Fig. 9, Table 4). All three have enough clay in their B-horizons for argillic horizons, but there are no visible clay coatings in the Hapludalf, which is on soapstone. Optical examination of the sand fraction from the C-horizon of the Hapludalf revealed only flaky talc-like grains and traces of actinolite. Talc and kerolite (hydrated talc) lose Figure 9. Nantahala (Buck Creek) ultramafic body. A. Alfisol on soapstone in cleared and burned Pitch Pine–Red Maple savanna. B. Mollisol on peridotite in overgrown Pitch Pine– White Oak savanna. 242 Northeastern Naturalist Vol. 16, Special Issue 5 Mg in weathering to form stevensite (Christidis and Mitsis 2006). Some of the cation-exchange capacity in the Hapludalf (CEC = Ca + Mg + acidity; Table 4) may be attributed to stevensite, but the very high CEC suggests that some Mg might be extracted from the crystal structures of talc or kerolite in the laboratory procedures. No X-ray diffactorgrams were obtained to confirm the presence of stevensite in the Bt horizon. The two Nantahala soils on peridotite have accumulated enough organic matter for mollic epipedons. The mollic epipedon is below the extremely acid A1 horizon in the Typic Argiudoll. Well-drained Mollisols (including Lithic and Typic Argiudolls) are sparse in of the southern Appalachian, and may occur only with certain parent materials that are not geographically extensive (Stanley Buol, North Carolina State University, Raleigh, NC, 2008 pers. comm.). Milton and Purdy (1988) sampled the foliage from several species of trees growing on serpentine soils in the Buck Creek and the Webster-Addie districts in the Blue Ridge Mountains, NC. White Oak leaves accumulated Table 4. Nantahala soils. Extractable cationsC Ca:Mg Depth Color (moist) TextureA LOIB (mmol+/kg) ratio pH Horizon (cm) (Munsell) (feel) (g/kg) Ca Mg Acidity (mol/mol) DWD Lithic Hapludalf in a cleared and burned Pitch Pine-Red Maple savanna Oi 1-0 Loose leaves A 0-11 10YR 3/2 L 110 21 232 37 0.09 6.0 Bt 11-23 7.5YR 4/4 CL - 9 655 18 0.01 6.4 C 23-38 N 8/0 L - 8 346 8 0.02 6.7 R 38+ Hard, slightly fractured soapstone Typic Argiudoll in Pitch Pine-White Oak savanna Oi 5–2 Loose leaves Oe 2–0 Fragmented, partially decomposed, slightly matted leaves A1 0–9 10YR 3/2 L 267 17 149 211 0.11 4.3 A2 9–22 10YR 3/3 GrL 55 8 73 28 0.11 5.8 A3 22–36 10YR3/3 GrCL 79 9 124 35 0.08 6.0 Bt 36–70 7.5YR 4/6 GrCL - 7 71 25 0.10 6.2 Cr 70–98 5–7.5YR 5/8 Soft, massive, weathered bedrock R 98–100+ Hard, slightly fractured peridotite Lithic Argiudoll in mixed Oak-Red Maple-Hemlock forest Oi/Oe 3–0 Loose over slightly matted and decayed leaves A1 0–2 10YR 2/2 L - - - - - - A2 2–9 10YR3/2 L 154 39 166 79 0.24 5.3 A3 9–22 10YR 3/3 L 79 17 97 48 0.17 5.8 Bt1 22–29 10YR 3/2 GrCL - 19 124 46 0.15 6.0 Bt2 29–34 7.5YR 5/6 vGrCL - 20 75 19 0.26 6.2 Cr 34–36 5YR 4/6 Soft, weathered bedrock 6.9 R 36+ Hard, massive dunitee ATexture symbols: Gr = gravelly, CL = clay loam, L = loam, vGr = very gravelly. BLoss of weight on ignition at 360 °C. CCations extractable with molar KCl, including acidity at pH 7. DGlass electrode pH in distilled water (1:1 water to soil). EAmphiboles (tremolite-actinolite) found in sand fractions from the Lithic Argiudoll may be the source of Ca, since dunite lacks Ca. 2009 E.B. Alexander 243 the most nickel, about 400 to 700 μg/g from five sites at Buck Creek, but they had Ni < 200 μg/g from sites at Webster-Addie. Soils of the Iredell series, which have mafic rather than ultramafic parent materials (PM), are known to support many plant species that are not found on adjacent soils of the Piedmont. Locally, areas of Iredell soils have been called blackjack soils because they have larger proportions of Blackjack Oak and Post Oak, relative to White Oak, than surrounding soils. Dayton (1966) found that the characteristic plants on the Iredell soils were those common on calcareous soils, in xeric habitats, or with prairie affinities. He did not find any distinctive soil physical or chemical properties, such as the low exchangeable Ca/Mg ratio of serpentine soils, that would cause the Iredell soils with mafic parent materials to have highly distinctive vegetation. Seven soils in Georgia, North Carolina, South Carolina, and Virginia identified as Iredell when sampled were analyzed in a National Resources Conservation Service laboratory (Table 5). These soils are generally moderately deep to saprolite, but numerous roots penetrate deeply into soft saprolite. Unfortunately, the soil parent materials were not identified in the pedon descriptions, but one of them was called “multicolored gneiss,” and minerals in the fine sand fraction were found to be mostly hornblende and feldspar with some quartz. Six of the seven soils have exchangeable Ca/Mg ratios <1.0 in their subsoils, and four of those have ratios <0.7. The soil reaction ranges widely from pedon to pedon, but can be generalized as slightly acid in the surface, neutral in the subsoil, and slightly alkaline in the saprolite. The Iredell soils with mafic parent material are intermediate between those with more silicic and those with ultramafic parent materials, and apparently the vegetation has characteristics that might be expected on soils with either silicic or ultramafic parent material. Table 5. A summary of Ca/Mg ratio and soil reaction data for “fine-earth” (particles <2.0 mm) from seven pedons of Iredell soils. Data from the National Resources Conservation Service. Note: The Iredell soils are currently classified as fine, mixed, active, thermic Oxyaquic Vertic Hapludalfs. Oxyaquic and vertic indicate that the soils are saturated with water for about a month or more each year, lack mottles and other redoximorphic features within the upper 75 cm, dry to form cracks, and have slickensides or wedge-shaped aggregates indicative of shrink-swell movement. Mixed refers to the mineralogy, which is mostly kaolinite, vermiculite, smectite, and goethite in the clay fractions, and active indicates clay with CEC = 0.4-0.6 mmol+/g. Site Exch. Ca/Mg (mol/mol) Soil ReactionB (based on pH) identificationA Surface Subsoil Saprolite Surface Subsoil Saprolite 69SC023001 >1.0 <1.0 <1.0 Slight acid Neutral Slight alkaline 69VA109002 >1.0 <0.5 <0.7 Slight acid Slight acid Neutral 84GA159004 >1.0 >1.0 >1.0 Moderate acid Slight acid Neutral 84NC063007 <0.7 <0.5 <0.5 Very strong acid Strong acid Slight acid 84NC063014 >1.0 <0.7 <0.7 Moderate acid Neutral Slight alkaline 85SC023001 >1.0 <0.7 <1.0 Slight alk. Neutral Slight alkaline 85SC023002 >1.0 <1.0 >1.0 Strong acid Neutral Moderate alkaline AThe date, state, and county are identified in the site designation. BRanges of pH in the reaction classes are give in the Soil Survey Manual (Soil Survey Staff 1993). 244 Northeastern Naturalist Vol. 16, Special Issue 5 Llano Uplift Serpentine soils of the Llano Uplift in central Texas are in Gillespie (304 ha) and Blanco (294 ha) counties (Allison et al. 1975, Dittemore and Allison 1979). This is a hilly area with altitudes of about 300 to 420 m. The serpentine soils are mostly gently sloping, but with steep slopes along Coal Creek. They are stony soils in a map unit of the Renick series (clayey, smectitic, thermic Ruptic-Lithic Haplustolls), with inclusions of rock outcrop and moderately deep Pachic Argiustolls. Soils on steeper slopes are similar to the Renick soils, but in clayey-skeletal families. A student of B.L. Allen (Maoui 1966) found that the fine clay in the Renick soils is mainly smectite and the coarse clay is predominantly serpentine and chlorite, with the serpentine more concentrated in the C horizon and the chlorite in the upper horizons. Some quartz, clino-amphibole of the tremolite-actinolite series, and talc were found in the Renick soils and may be from schists that are closely associated with the serpentinite, although tremolite, or actinolite, and talc are commonly formed by alteration of the same peridotite from which the serpentine was produced by serpentinization. The dominant serpentine vegetation is oak-juniper-mesquite savanna. Nixon and McMillan (1964) studied the grasses at six sites in Texas, including two in northeastern Gillespie County—one on serpentine soils and the other on granitic soils. An oak-mesquite savanna on the granitic soils was represented by Post Oak, Ulmus crassifolia (Cedar Elm), and Prosopis glandulosa, var. glandulosa (Honey Mesquite), with Little Bluestem, Panicum virgatum (Switchgrass), Indian Grass, and Bouteloua curtipendula (Sideoats Grama). The woody vegetation was scanty on the serpentine soils, but the four grasses mentioned for the granitic soils were common, along with Bouteloua hirsuta (Hairy Grama) and Hilaria belangeri (Curly-mesquite), although Indian Grass was sparse. Other common species on the serpentine soils that were mentioned by Maoui (1966) are Acacia greggii (Catclaw), Diospyros texana (Persimmon), Mahonia trifoliolata (Algerita), Opuntia sp. (prickly pear), composite forbs in the Thelesperma and Chaetopappa genera, and several grass species. Among the grass species are Nassella leucotricha (Texas Wintergrass), Digitaria cognata (Witchgrass), Bouteloua rigidiseta (Texas Grama), Threeawn, Sporobolus cryptandrus (Sand Dropseed), Eragrostis intermedia (Plains Lovegrass), and Panicum hallii (Hall’s Panic Grass). Yucca consticta (Buckley’s Yucca) is another species that is common on the steep serpentine soils along Coal Creek (Fig. 10). Summary of the serpentine soils and soil-vegetation relationships A broad range of serpentine soils and vegetation occurs from Newfoundland to Alabama. The serpentine soils are distinguished more by their mineralogy and chemistry than by their morphology. The main morphological differences from nonserpentine soils are that the cold serpentine soils lack the distinctive albic (bleached) horizons that are characteristic of Spodosols (Podzols), and the greater amounts of secondary iron oxides in warm, strongly weathered serpentine soils commonly gives them redder colors than 2009 E.B. Alexander 245 nonserpentine soils. Also, in some areas where the serpentine soils are commonly Mollisols, the nonserpentine soils have no mollic epipedons. Although botanists commonly concentrate on the shallow serpentine soils that have the most distinctive serpentine vegetation, serpentine soils range from shallow to very deep. There is no evidence that serpentine soils are in general more shallow than nonserpentine soils over a large area. Perhaps the most comprehensive compilation of data comparing physical properties of serpentine and nonserpentine soils is for available-water capacities (AWCs) in soils of the Klamath and Shasta-Trinity National Forests, CA (Alexander et al. 2007), and the data are inconclusive: they show no definite AWC differences between serpentine and nonserpentine soils. The organic carbon in the upper meter of serpentine soils in eastern North America is comparable to that in other soils (Table 6). Although the coefficients of variation (CV) are high (Batjes 1996)—43% for Orthic Acrisols Table 6. Organic carbon in Appalachian serpentine soils (Table 3) compared to soils of the World (Batjes 1996). Soil organic carbon (kg/m2) World soils Serpentine soilsD WRBA soil group USDAB soil taxonomy 0–0.5 m 0–1.0 m 0–0.5 m 0–1.0 m World soils (n)C Serpentine soils (n)C Eutric Regosols (29,21) Orthent (1,0) 3.6 4.6 2.7 - Mollic Gleysols (39,28) Aquoll (1,0) 13.1 16.8 11.0 - Eutric Cambisols (99,68) Eutrudept (1,0) 6.3 8.8 5.5 - Luvisols (555,377) Chromic (92,56) Typic Hapludalfs (2,2) 5.5 8.0 5.4 7.8 Gleyic (77,52) Aquic Hapludalf (1,0) 4.7 7.0 5.5 - Orthic (127,86) Typic Hapludalfs (3,2) 4.7 7.1 5.0 6.4 Orthic Acrisols (60,55) Kanhapudalf (1,1) 5.0 7.1 7.0 9.8 AFAO/ISRIC/ISSS (1998). BSoil Survey Staff (1999). CNumbers of sample pedons (n) for 0–0.5 and 0–1.0 m depths. DMeans of data in Table 3. Figure 10. Llano uplift, TX. A. Serpentinite quarry, and, across Coal Creek, landscape on Renick soil map unit. B. Steep slope on serpentinite (foreground) along Coal Creek. 246 Northeastern Naturalist Vol. 16, Special Issue 5 to 122% for Eutric Regosols—the few pedons in Table 6 indicate that the amounts of organic carbon in the serpentine soils do not seem to be much different from the amounts in other soils. The main chemical features that distinguish serpentine soils are very high Mg and high first transition element contents, especially Cr, Co, and Ni, compared to other soils. It is very low exchangeable Ca/Mg ratios (Table 3), and possibly high Ni contents, that impose the greatest limitations on plants. Any effects of relatively low K and P in serpentine soils are masked by the effects of very high Mg and low Ca concentrations (Alexander et al. 2007). Nitrogen deficiency symptoms may appear upon heavy fertilization of serpentine soils with other elements (Moore and Zimmerman 1977), but that happens with most soils. Serpentine soils are not particularly low in N (Alexander et al. 2007). Although the lesser density and stature of serpentine vegetation are the most readily visible differences from nonserpentine vegetation, the plant species distributions are generally quite different, also. Many plants on serpentine soils with low available-water capacities occur mostly, or only, on serpentine soils, and some are isolated from their common geographic ranges (disjunct distributions). These unique vegetation distributions makes shallow serpentine soils very interesting habitats for botanists to scrutinize. Literature Cited Alexander, E.B., R.G. Coleman, T. Keeler-Wolf, and S. Harrison. 2007. Serpentine Geoecology of Western North America. Oxford University Press, New York, NY. 512 pp. Allison, J.E., G.W. Dittmar, and J.L. Hensell. 1975. Soil survey of Gillespie County, Texas. USDA, National Resources Conservation Service, Washington, DC. 80 pp. Barton, A.M., and M.D. Wallenstein. 1997. Effects of invasion of Pinus virginiana on soil properties in serpentine barrens in southeastern Pennsylvania. Journal of the Torrey Botanical Society 124:297–305. Batjes, K.H. 1996. Total carbon in the soils of the world. European Journal of Soil Science 47:151–163. Bouchard, A., H. Stuart, and E. Rouleau. 1978. Vascular flora of St. Barbe South district, Newfoundland: An interpretation based on biophysiographic areas. Rhodora 80:228–308. Boudette, E.L. 1982. Ophiolite assemblage of early Paleozoic age in central western Maine. Geological Association on Canada, Special Paper 24:209–230. Butler, J.R. 1989. Review and classification of ultramafic bodies in the Piedmont of the Carolinas. Geological Society of America, Special Paper 231:19–31. Christidis, G.E., and I. Mitsis. 2006. A new Ni-rich stevensite from the ophiolite complex of Othrys, Greece. Clays and Clay Minerals 54:653–666. Cleaves, E.T., D.W. Fisher, and O.P. Bricker. 1974. Chemical weathering of serpentine in the eastern Piedmont of Maryland. Geological Society of America, Bulletin 85:437–444. Dayton, B.R. 1966. The relationship of vegetation to Iredell and other Piedmont soils in Granville County, North Carolina. Journal of the Elisha Mitchell Scientific Society 82:108–118. 2009 E.B. Alexander 247 Dearden, P. 1979. Some factors influencing the composition and location of plant communities on a serpentine bedrock in western Newfoundland. Journal of Biogeography 6:93–104. De Kimpe, C., and J. Zizka. 1973. Weathering and clay formation in a dunite deposit at Asbestos. Canadian Journal of Soil Science 10:27–35. De Kimpe, C., J. Dejou, and Y. Chevalier. 1987. Évolution géochimique superficielle des pyroxénites ignées du Mont Saint-Bruno, Québec. Canadian Journal of Soil Science 24:760–770. Denny, C.S. 1982. Geomorphology of New England. US Geological Survey, Professional Paper 1208. 18 pp. Dittemore, W.H., Jr., and J.E. Allison. 1979. Soil survey of Blanco and Burnet counties, Texas. USDA, National Resources Conservation Service, Washington, DC. 116 pp. Eyles, N., and A. Miall. 2007. Canada Rocks: The Geologic Journey. Fitzhenry and Whiteside, Markham, ON, Canada. 512 pp. FAO/ISRIC/ISSS. 1998. World reference base for soil resources. FAO World Resources Report No. 84, Food and Agriculture Organization of the United Nations, Rome, Italy. 161 pp. Garrison, J.R., Jr. 1981. Coal Creek serpentinite, Llano uplift, Texas: A fragment an incomplete ophiolite. Geology 9:225–230. Gerbi, C.C., S.E. Johnson. and J.N. Aleinikoff. 2006. Origin and orogenic role of the Chain Lakes massif, Maine and Quebec. Canadian Journal of Earth Science 43:339–366. Gorring, M.L., and H.R. Naslund. 1995. Geochemical reversals within the lower 100 m of the Palisades sill, New Jersey. Contributions to Mineralogy and Petrology 119:263–276. Gray, J.T., and R.J.E. Brown. 1979. Permafrost existence and distribution in the Choc-Chocs Mountains, Gaspésie, Québec. Géographie Physique et Quaternaire 33:299–316. Hack, J.T. 1982. Physiographic divisions and differential uplift in the Piedmont and Blue Ridge. US Geological Survey, Professional Paper 1265. 49 pp. Hanan, B.B., and A. K. Sinha. 1989. Petrology and tectonic affinity of the Baltimore mafic complex, Maryland. Geological Society of America, Special Paper 231:1–18. Harris, T.B., F.C. Olday, and N. Rajakaruna. 2007. Lichens of Pine Hill, a peridotite outcrop in eastern North America. Rhodora 109:430–447. Harris, W.G., L.W. Zelazny, and J.C. Baker. 1984. Depth and particle size distribution of talc in a Virginia piedmont Ultisol. Clays and Clay Minerals 32:227–230. Hatch, N.L., Jr. 1982. Taconian line in western New England and its implications to Paleozoic tectonic history. Geological Association on Canada, Special Paper 24:67–85. Hibbard, J.P., C.R. van Staal, D.W. Rankin, and H. Williams. 2006. Lithotectonic map of the Applachian orogen, Canada-United States of America. Geological Survey of Canada, “A” Series Map 2096 A. Huggett, R.J. 1995. Geoecology. Routledge, London, UK. 320 pp. Hochman, D.J. 2001. Pinus virginiana invasion and soil-plant relationships of Soldier’s Delight Natural Environmental Area, a serpentine site in Maryland. M.Sc. Thesis. University of Maryland, College Park, MD. 143 pp. Hull, J.C., and S.G. Wood. 1984. Water relations of oak species on and adjacent to a Maryland serpentine soil. American Midland Naturalist 112:224–234. 248 Northeastern Naturalist Vol. 16, Special Issue 5 Jones, W.E. 1962. Soil survey of Cherokee County, South Carolina. US Department of Agriculture,Washington, DC. 105 pp. Larabee, D.M. 1966. Map showing distribution of ultramafic and intrusive mafic rocks from northern New Jersey to Alabama. US Geological Survey, Map I–476. Lyons, J.B., E.L. Boudette, and J.N. Aleinikoff. 1982. The Avalon and Gander Zones in Central Eastern New England. Geological Association on Canada, Special Paper 24:43–65. Mansberg, L., and T.R. Wentworth. 1984. Vegetation and soils of a serpentine barren in western North Carolina. Bulletin of the Torrey Botanical Club 111:273–286. Maoui, H.M. 1966. A Mineralogical and Genetic Study of Serpentine Derived Soils in Gillespie County, Texas. M.Sc. Thesis, Texas Tech University, Lubbock, TX. 127 pp. Merrill, G.P. 1906. A Treatise on Rocks, Rock-weathering, and Soils. Macmillan, New York, NY. 400 pp. Milton, N.M., and T.L. Purdy. 1988. Response of selected plant species to nickel in western North Carolina. Castanea 53:207–214. Misra, K.C., and F.B. Keller. 1978. Ultramafic bodies in the southern Appalachians: A review. American Journal of Science 278:389–418. Mittwede, S.K. 1989. The Hammet Grove metaigneous suite: A possible ophiolite in the north-western South Carolina Piedmont. Geological Society of America, Special Paper 231:45–62. Moore, T.R., and R.C. Zimmerman. 1977. Establishment of vegetation on serpentine asbestos mine wastes, southeastern Québec, Canada. Journal of Applied Ecology 14:589–599. Mosher, S. 1998. Tectonic evolution of the southern Laurentian Grenville orogenic belt. Bulletin of the Geological Society of America 110:1357–1375. Nixon, E.S., and C. McMillan. 1964. The role of soil in the distribution of four grass species in Texas. American Midland Naturalist 71:114–140. Ogg, C.M., and B.R. Smith. 1993. Mineral transformations in Carolina Blue Ridge- Piedmont soils weathered from ultramafic rocks. Journal of the Soil Science Society of America 57:461–472. Panaccione, D.G., N.L. Sheets, S.P. Miller, and J.R. Cummings. 2001. Diversity of Cenococcum geophilum isolates from serpentine and non-serpentine soils. Mycologia 93:645–652. Parisio, S. 1981. The genesis and morphology of a serpentine soil in Staten Island. Staten Island Institute of Arts and Sciences, Proceedings 31:2–17. Radford, A.E. 1948. The vascular flora of the olivine deposits of North Carolina and Georgia. Journal of the Elisha Mitchell Scientific Society 64:45–106. Rabenhorst, M.C., and J.E. Foss. 1981. Soil and geologic mapping over mafic and ultramafic parent materials in Maryland. Soil Science Society of America Journal 45:1156–1160. Rabenhorst, M.C., J.E. Foss., and D.S. Fanning. 1982. Genesis of Maryland soils formed from serpentinite. Journal of the Soil Science Society of America 46:607–616. Rajakaruna, N., T.B. Harris, and E.B. Alexander. 2009. Serpentine geoecology of eastern North America: A review. Rhodora 111:21–108. Reed, C.F. 1986. Flora of the Serpentinite Formations in Eastern North America, with Descriptions of the Geomorphology and Mineralogy at the Formations. Contributions of the Reed Herbarium 30. Reed Herbarium, Baltimore, MD. 858 pp. 2009 E.B. Alexander 249 Roberts, B.A. 1980. Some chemical and physical properties of serpentine soils from western Newfoundland. Canadian Journal of Soil Science 60:231–240. Roberts, B.A. 1992. Ecology of serpentinized areas. Pp. 75–113, In B.A. Roberts and J. Proctor (Eds.). The Ecology of Areas with Serpentinized Rocks: A World View. Kluwer, Dordrecht, The Netherlands. 427 pp. Sirois, L., and M.M. Grandtner. 1992. A phyto-ecological investigation of the Mount Albert serpentine plateau. Pp. 115–133, In B.A. Roberts and J. Proctor (Eds.). The Ecology of Areas with Serpentinized Rocks: A World View. Kluwer, Dordrecht, The Netherlands. 427 pp. Sirois, L., F. Lutzoni, and M.M. Grandtner. 1988. Les lichens sur serpentine et amphibolite du plateau du Mont Albert, Gaspésie, Québec. Canadian Journal of Botany 66:851–862. Soil Classification Working Group. 1998. The Canadian System of Soil Classification. Agriculture and Agri-Food Canada, Ottawa, ON, Canada. Publication 1646, 187 pp. Soil Survey Staff. 1993. Soil Survey Manual. Agriculture Handbook No. 18. US Government Printing Office, Washington, DC. 437 pp. Soil Survey Staff. 1999. Soil Taxonomy: A Basic System for Making and Interpreting Soil Surveys. USDA, Agriculture Handbook No. 436. US Government Printing Office, Washington, DC. 869 pp. Terlizza, D.E., and E.P. Karlander. 1979. Soil algae from a Maryland serpentine formation. Soil Biology and Biochemistry 11:205–207. Thomas, D.J. 1998. Soil survey of Clay County, North Carolina. USDA, National Resources Conservation Service, Washington, DC. 279 pp. Tyndall, R.W. 1992. Historical considerations of conifer expansion in Maryland serpentine “barrens.” Castanea 57:123–131. Tyndall, R.W. 1994. Contributions of the barrens symposium, preface. Castanea 59:182–183. Wheeler, A.G. 1988. Diabrotica cristata, a chrysomelid (Coleoptera) of relict Midwestern prairies discovered in eastern serpentine barrens. Entomological News 99:134–142. Williams, H., and P. St-Juliens. 1982. The Baie Verte-Brompton Line: Continentocean interface in the Northern Appalachians. Geological Association on Canada, Special Paper 24:177–207. Wing, L.A. 1951. Asbestos and serpentine rocks of Maine. Maine Geological Survey, Augusta, ME. Report of the State Geologist 1949–1950:35–46. Worthington, J.E. 1964. An exploration program for nickel in the southeastern United States. Economic Geology 59:97–109. Zika, P.F., and K.T. Dann. 1985. Rare plants on ultramafic soils in Vermont. Rhodora 87:293–304. 250 Northeastern Naturalist Vol. 16, Special Issue 5 Appendix 1. Taxononic names, botanical authorities, and some common names of plants. Taxonomic name Common name Abies balsamifera (L.) Mill Balsam Fir Acacia greggii A Gray Catclaw Acer rubrum L. Red Maple Adiantum aleuticum (Rupr.) Paris Maidenhair Fern Agalinis acuta Pennell Gerardia, or False Foxglove Alnus crispa (Ait.) Pursh Scrub Alder Amelanchier arborea (Michx.) Fernald Serviceberry Armeria ladradorica Waldr. Thrift Andromeda polifolia L. var. glaucophylla (Link) DC Bog Rosemary Andropogon gerardii Vitman Big Bluestem Andropogon scoparius (now Schizachyrium scoparium) Little Bluestem Arenaria humifusa Wahlenb. Low Sandwort Arenaria macrophylla (Hook.) Fenzl Largeleaf Sandwort Arenaria marcesens (now Minuartia marcesens) Serpentine Stitchwort Aristida purpurascens Poir. Arrowleaf Threeawn Asplenium trichomanes L. Maidenhair Spleenwort Aster depauperatus (now Symphotricum depauperatum) Serpentine Aster Betula glandulosa Michx. Dwarf Birch Betula pumila L. Bog Birch Bouteloua curtipendula (Michx.) Torr. Sideoats Grama Bouteloua hirsuta Lag. Hairy Grama Bouteloua rigidiseta (Steud.) Hitchc. Texas Grama Campanula rotundifolia L. Bluebell Bellflower Campylium stellatum (Hedw.) C.E.O. Jensen Campylium Moss Carex echinata Murray Star Sedge Ceanothus americanus L. Jersey Tea Cerastium arvense L. Chickweed Cetraria laevigata Rass. Striped Iceland Lichen Cypripedium caleolus L. Yellow Lady’s Slipper Danthonia spicata (L.) Roem. & Schult. Poverty Oatgrass Deschampsia caespitosa (L.) Beauv. Tufted Hairgrass Deschampsia flexuosa (L.) Trin. Wavy Hairgrass Diapensia lapponica L. Pincushion Dicranum bonjeanii De Not. Bonjean’s Dicranum Moss Digitaria cognata (J.A. Schulles) Pilger Witchgrass Diospyros texana Scheele Persimmon Drosera rotundifolia (L.) Roundleaf Sundew Dryas integrifolia Vahl. Mountain-avens Eragrostis intermedia Hitch. Plains Lovegrass Festuca filiformis Purret Fineleaf Sheep Fescue Festuca rubra L. Red Fescue Hilaria belangeri (Steud.) Nash Curly-mesquite Hylocomium splendens (Hedw.) Schimp Feather Moss Juncus trifidis L Highland Rush 2009 E.B. Alexander 251 Taxonomic name Common name Juniperus communis L. Dwarf Juniper Juniperus horizontalis Moench Creeping Juniper Juniperus virginiana L. Virginia Juniper Kalmia latifolia L. Mountain Laurel Larix larcina (Du Roi) K. Koch Tamarack Ledum groenlandicum Oeder Labrador Tea Linum sulcatum Riddell Flax Lychnis alpina L. Red Alpine Campion Mahonia trifoliolata Fedde Algerita Minuartia marcescens (Fernald) House Serpentine Stitchwort Morella pensylvanica (Mirb.) Kartez Bayberry Myrica gale L. Sweet Gale Nassella leucotricha (Trin. & Rupr.) R.W. Pohl Texas Wintergrass Packera plattenis (Nutt.) W.A. Webber & A. Löve Prairie Groundsel Panicum hallii Vasey Hall’s Panic Grass Panicum virgatum L. Switchgrass Physocarpus opulifolius (L.) Maxim. Ninebark Picea glauca (Moench) Voss White Spruce Picea mariana Britton, Sterns & Pagenb. Black Spruce Phlox sublata L. Moss Phlox Pinus rigida Mill. Pitch Pine Pinus virginiana Mill. Virginia Pine Pleurozium schreberi (Brid.) Mitt. Big Redstem Moss Potentilla fruticosa L. Cinquifoil Prosopis glandulosa var. glandulosa Torr. Honey Mesquite Quercus alba L. White Oak Quercus falcata Michx. Southern Red Oak Quercus marilandica Münchh. Blackjack Oak Quercus stellata Wagenh. Post Oak Quercus velutina Lam. Black Oak Rhacomitrium lanuginosum (Hedw.) Brid. Hoary Rock Moss Rhododendron calendulaceum (Michx.) Torr. Azalea Rhododendron lapponicum (L.) Wahlenb. Lapland Rosebay Rubus allegheniensis Porter Blackberry Salix arctica Richardson Arctic Willow Sassafras albidum (Nutt.) Nees Sassafras Saxafraga oppositifolia L. Purple Mountain Saxafrage Schizachyrium scoparium (Michx.) Nash Little Bluestem Selaginella rupestris (L.) Spring Rock Spike-moss Selaginella selaginoides (L.) Mart. & Schrank Club-moss Senecio pauperculus Michx. Balsam Ragweed Silene acaulis L. Moss Campion Smilacina trifolia (L.) Desf. Twisted-stalk Smilax glauca Walt. Cat Greenbrier Smilax rotundifolia L. Roundleaf Greenbrier Solidago hispida Muhl. Ex Wild. Hairy Goldenrod Sorghastrum nutans L. Nash Indian Grass Sporobolus cryptandrus (Torr.) Gray Sand Dropseed 252 Northeastern Naturalist Vol. 16, Special Issue 5 Taxonomic name Common name Sporobolus heterolepis (Gray) Gray Prairie Dropseed Symphotricum depauperatum (Fernald) G.L. Nesom Serpentine Aster Talinum teretifolium Pursh Flameflower Thuja occidentalis L. White Cedar Tsuga canadensis (L.) Carr. Hemlock Ulmus crassifolia Nutt. Cedar Elm Vaccinium oxycoccus L. Small Cranberry Vaccinium stamineum L. Deerberry Vaccinium uliginosum L. Alpine Blueberry Viburnum cassinoides L. Wild-raisin Yucca constricta Buckley Buckley’s Yucca