Floristics of Difficult Creek Natural Area Preserve: a Piedmont mafic woodland complex in Halifax County, Virginia, U.S.A.
The 331-hectare (819-acre) Difficult Creek Natural Area Preserve (DCNAP) was established in Halifax County, Virginia to protect and manage habitat for rare vascu-lar plant species and animals, and to restore plant communities. Mafic metavolcanic rocks of the Virgilina Formation and felsic metavolcanic and metasedimentary rocks of the Aaron Formation comprise the geologic units on the preserve. The Virgilina-derived soils have high shrink-swell potential, a dense hardpan layer, relatively high base status, and a significant gravelly or stony component; these soil conditions support the highest density of rare plant species known on the preserve. The first noteworthy vascular plant species were documented from the property in 1972 by botanist Alton Harvill of Longwood University, but detailed investigations of the flora did not begin until the site was revisited by the second author in 1993. Rare plant inventory has been the primary focus of botanists since that time. In 2001, the property was acquired by the Virginia Department of Conservation and Recreation, Division of Natural Heritage (DCR) and dedicated as a state Natural Area Preserve, at which point active management for natural communities and associated rare species was initiated. Since the rare plants on site thrive in open woodland or savanna-like conditions, prescribed burns and timber harvests have been used by DCR stewards to restore habitat after decades of fire suppression and conversion of hardwood stands to loblolly pine plantations. In 2018, a thorough floristic study was initiated to highlight the significance of this flora beyond the documentation of rare plants. The two-year inventory documented 653 plant taxa, comprising 326 genera in 106 families. Fourteen of these species are of conservation concern at the global or state level; an additional 12 taxa are considered uncommon and of potential conservation concern (Townsend 2019). These rare or uncommon species are components of two globally rare plant communities. In addition, the globally rare lepidopteran, Erynnis martialis (Mottled Duskywing), occurs on the preserve, the only extant population known in Virginia. Due to agricultural impacts and widespread fire exclusion, few analogs to this flora exist within the southern Piedmont of Virginia.
Aldrich, S.R., C.W. Lafon, H.D. Grissino-Mayer, G.G. DeWeese, & J.A. Hoss. 2010. Three centuries of fire in montane pine-oak stands on a temperate forest landscape. Appl. Veg. Sc. 13:36–46.
Bailey, C.M., W.C. Sherwood, L.S. Eaton, & D.S. Powa rs. 2016. The geology of Virginia. Virginia Mus. Nat. Hist. Publ. Special Publ. 18. Martinsville, VA, U.S.A.
Barden, L.S. 1997. Historic prairies in the Piedmont of North South Carolina, USA. Nat. Areas J. 17:149–152.
Beverly, R., Jr. 1705 (revised & enlarged 1722). The history and present state of Virginia, in four parts. https://docsouth.unc.edu/southlit/beverley/beverley.html) Accessed 13 Feb 2020.
Burns, R.M. & B.H. Honkala, tech. coord. 1990a. Silvics of North America: Volume 1. Conifers. United States Department of Agriculture (USDA), Forest Service, Agric. Handb. 654.
Burns, R.M. & B.H. Honkala, tech. coord. 1990b. Silvics of North America: Volume 2. Hardwoods. United States Department of Agriculture (USDA), Forest Service, Agric. Handb. 654.
Butaye, J.D. Adriaens, & O. Honnay. 2005. Conservation and restoration of calcareous grasslands: A concise review of the effects of fragmentation and management on plant species. Biotechno. Agron. Soc. Environm. 9:111–118.
Byrd, W. & E. Ruffin, ed. 1841. The Westover manuscripts: Containing the history of the dividing line betwixt Virginia and North Carolina; A journey to the land of Eden, A.D.; and A progress to the mines. [Printed by E. and J.C. Ruffin, Petersburg, VA, U.S.A.] [Web.] Retrieved from the Library of Congress, https://lccn.loc.gov/rc01002772.
Coladonato, M. 1992. Carya tomentosa. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/tree/cartom/all.html. Accessed 22 Jan 2019.
Copenheaver, C.A., S.A. Predmore, & D.N. Askam it. 2009. Conversion of rare grassy openings to forest: Have these areas lost their conservation value? Nat. Areas J. 29:133–139.
Cumming, W.P. 1991. Johann (John) Lederer. In: William S. Powell, ed. Dictionary of North Carolina biography. University of North Carolina Press, Chapel Hill, U.S.A. https://www.ncpedia.org/biography/lederer-johann-or-john. Accessed 23 Feb 2020.
Davis, Jr., J.E., C. McRae, B.L. Estep, L.S. Barden, & J.F. Matthews. 2002. Vascular flora of Piedmont Prairies: Evidence from several prairie remnants. Castanea 67:1–12
Dayton, B.R. 1966. The relationship of vegetation to Iredell and other Piedmont soils in Granville County, Virginia. J. Elisha Mitchell Sci. Soc. 82:108–118.
Department of Commerce, Bureau of the Census. E. Dana Durand, Director. 1913. Thirteenth Census of the United States taken in the year 1910. Volume VII. Agriculture 1909 and 1910. Reports by States, With Statistics for Counties. Nebraska-Wyoming. Alaska, Hawaii, and Porto Rico. Government Printing Office, Washington, U.S.A.
Eastham, D.H., H.L. Gillespie Jr., G.A. Hammer, l.A. Dail, & R. Jones. 2009. Soil survey of Halifax County and the city of South Boston, Virginia. United States Dept. of Agriculture, Natural Resources Conservation Service in Cooperation with Virginia Polytechnic Institute and State University, Washington, DC, U.S.A.
Fernald, M.L. 1937. Plants of the Inner Coastal Plain of Virginia. Rhodora 39:321–491.
Fernald, M.L. 1941. Another century of additions to the flora of Virginia. Rhodora 43:485–657.
Fleming, G.P. & K.D. Patterson 2017. Natural communities of Virginia: Ecological groups and community types. Natural Heritage Technical Report 17-07. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA, U.S.A.
Fleming, G.P. & N. Van Alstine. 1994. A natural heritage inventory of Fort Pickett, Virginia. Natural Heritage Technical Report 94-3. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, Virginia. Unpublished report submitted to the U.S. Army, U.S.A.
Foster, D.R. & G. Motzkin. 2003. Interpreting and conserving the openland habitats of coastal New England: Insights from landscape history. Forest Ecol. Managem. 185:127–150.
Fowler, C. & E. Konopik. 2007. The history of fire in the southern United States. Human Ecol. Rev. 14:165–176.
Frost, C.C. 1998. Presettlement fire frequency regimes of the United States: A first approximation. In: Teresa L. Pruden and Leonard A. Brennan, eds. Fire in ecosystem management: Shifting the paradigm from suppressioin to perception. Tall Timbers Fire Ecol. Conf. Proc. No. 20. Tall Timbers Research Station, Tallahassee, FL, U.S.A. Pp. 70–81.
Gould, F.W. 1941. Plant indicators of original prairies. Ecology 22:427–429.
Harvill, A.M. 1973. Some new and very local populations of rare species in Virginia. Castanea 38:305–307.
Kartesz, J.T. 2015. The biota of North America Program (BONAP). Taxonomic Data Center. (http://www.bonap.net/tdc). Chapel Hill, N.C. [maps generated from Kartesz, J.T. 2015. Floristic synthesis of North America, Version 1.0. Biota of North America Program (BONAP). (in press)]
Klopf, R.P., R.K. Myers, J.C. Ludwig, & C.A. Woodall. 2018. Management plan for Difficult Creek Natural Area Preserve. Natural Heritage Technical Report #18-15. Virginia Department of Conservation and Recreation, Division of Natural Heritage. Richmond, VA, U.S.A.
Kneller, M. & D. Peteet. 1993. Late-Quaternary climate in the Ridge and Valley of Virginia, U.S.A.: Changes in vegetation and depositional environment. Quatern. Sci. Rev. 12:613–628.
Kreisa, R.D. 1980. Geology of the Omega, South Boston, Cluster Springs and Virgilina Quadrangles, Virginia: Virginia Division of Mineral Resources Publication 5. Charlottesville, VA, U.S.A.
laney, F.B. 1917. The geology and ore deposits of the Virgilina district of Virginia and North Carolina. Virginia Geological Survey, Univ. Virginia, Bull. No. 14. Prepared jointly by the Virginia geological survey and the North Carolina geological and economic survey. University of Virginia, Charlottesville, U.S.A.
Leblond, R.J., J.F. Townsend, & J.C. Ludwig. 2020. Two new species of Dichanthelium (Poaceae) from the Mountains and Piedmont of Virginia, one with an outlier in Pennsylvania. J. Bot. Res. Inst. Texas 14(2):189–198.
Maxwell, H. 1910. The use and abuses of forests by the Virginia Indians. William & Mary Quart. 19(2):73–103.
Mehlich, A. 1984. Mehlich 3 soil test extractant: A modification of Mehlich 2 extractant. Commun. Soil Sci. Pl. Analysis 15:1409–1416.
Nowacki, G.J. & M.D. Abrams. 2008. The demise of fire and the “mesophication” of forests in the eastern United States. Bioscience 58(2):123–138.
Nesom, G.L., D.D. Spaulding, & H.E. Horne. 2014. Further observations on the Oxalis dillenii group (Oxalidaceae). Phytoneuron 2014-12:1–10.
Peet, R.K., T.R. Wentworth, & P.S. White. 1998. A flexible, multipurpose method for recording vegetation composition and structure. Castanea 63(3):262–274.
Reed, C.L. 2018. Guide to the vascular flora of the Eno River Diabase Sill Plant Preserve, Durham County, North Carolina. Unpublished Masters Thesis, North Carolina State University, Raleigh, U.S.A.
Roble, S.M. 2016. Natural Heritage Resources of Virginia: Rare animals. Natural Heritage Technical Report 16-07. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA, U.S.A.
Schmidt, J.M. 2002. A flora of the Rock Hill Blackjacks heritage preserve, York County, South Carolina. Castanea 67(3):247–279.
Sørensen, T. 1948. A method of establishing groups of equal amplitude in plant sociology based on similarity of species and its application to analyses of the vegetation on Danish commons. Biol. Skr. 5(4):1–34.
Sorrie, B.A., J.B. Gray, & P.J. Crutchfield. 2006. The vascular flora of the longleaf pine ecosystem of Fort Bragg and Weymouth Woods, North Carolina. Castanea 71(2):129–161.
Southeast Regional Climate Center. 2019. http://www.sercc.com/cgi-bin/sercc/cliMAIN.pl?va3695 Accessed 24 Jan 2019.
Stanley, J.S., A. Krings , J.M. Stucky, & R.R. Braham . 2019. Guide to the vascular flora of Picture Creek Diabase Barrens, Granville County, North Carolina, U.S.A. Sida, Bot. Misc. 51. Botanical Research Institute of Texas, Fort Worth, U.S.A.
Thiers, B. (2016) Index herbariorum: A global directory of public herbaria and associated staff. New York Botanical Garden’s Virtual Herbarium.http://sweetgum.nybg.org/science/ih/
Thornhill R., A. Krings, D. Lindbo, & J. Stucky. 2014. Guide to the vascular flora of the savannas and flatwoods of Shaken Creek Preserve and Vicinity (Pender & Onslow Counties, North Carolina, U.S.A.). Biodivers. Data J. 2: e1099. doi:10.3897/BDJ.2.e1099
Tirmenstein, D.A. 1991a. Carya ovata. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/tree/carova/all.html [2019, January 22].
Tirmenstein, D.A. 1991b. Carya glabra. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/tree/cargla/all.html [2019, January 22].
Townsend, J.F. 2004. Natural Heritage Resources of Virginia: Rare plants. Natural Heritage Tech. Rep. 04-06. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, U.S.A. Unpublished report. April 2004.
Townsend, J.F. 2019. Natural Heritage Resources of Virginia: Rare plants. Natural Heritage Tech. Rep. 19-11. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, Virginia. Unpublished report. March 2019.
Trimble, S.W. 1974 (2nd ed. 2008). Man-induced soil erosion on the southern Piedmont 1700–1970. Enhanced second edition with a new Foreword by Andrew Goudie. Soil and Water Conservation Society, Ankeny, IA, U.S.A. USNVC [United States National Vegetation Classification]. 2019. United States National Vegetation Classification Database, V2.0. Federal Geographic Data Committee, Vegetation Subcommittee, Washington, DC, U.S.A. URL: http://usnvc.org Accessed 10 Dec 2019.
Virginia Botanical Associates. 2019. Digital atlas of the Virginia flora (http://www.vaplantatlas.org). c/o Virginia Botanical Associates, Blacksburg, U.S.A. Accessed 29 Jul 2020.
Virginia Department of Conservation and Recreation, Division of Natural Heritage (VA DCR-DNH). 2019. VA Plots, the DCR-DNH Vegetation Plots Database. Data exported on 22 Nov 2019. Richmond, VA, U.S.A.
Virginia Department of Conservation and Recreation - Division of Natural Heritage and Virginia Department of Gam e and Inland Fisheries (VA DCR-DGIF). 2013. Atlas of rare butterflies, skippers, moths, dragonflies, and damselflies of Virginia (DCR-DGIF). Accessed at www.vararespecies.org on 11 Feb 2020.
Virginia Land Office. 2019. Surveys of the Virginia Land Office before 1779, State government records collection, The Library of Virginia, Archives Branch, Richmond, VA, U.S.A. Accessed 2019.
Walker, J.L. & R.K. Peet. 1983. Composition and species diversity of pine-wiregrass savannas of the Green Swamp, North Carolina. Vegetatio 55:163–179.
Weakley, A.S. & D.B. Poindexter. 2012. A new species of Marshallia (Asteraceae, Helenieae, Marshalliinae) from mafic woodlands and barrens of North Carolina and Virginia. Phytoneuron 2012-105:1–17.
Weakley, A.S., J.C. Ludwig, & J.F. Townsend. 2012. Flora of Virginia. Bland Crowder, ed. Foundation of the Flora of Virginia Project Inc, Richmond. Botanical Research Institute of Texas Press, Fort Worth, U.S.A.
Weakley, A.S. 2015. Flora of the Southern and Mid-Atlantic States, working draft of May 2015. University of North Carolina Herbarium, North Carolina Botanical Garden, Chapel Hill, N.C. Accessed at http://www.herbarium.unc.edu/flora/htm.