Endemic plants of the central grassland of North America: distribution, ecology, and conservation status
DOI :
https://doi.org/10.17348/jbrit.v11.i1.1172Mots-clés :
Central Grassland, conservation, endemism, floristic diversity, geobotanyRésumé
This paper enumerates the endemic plants of the Central Grassland of North America. The Central Grassland encompasses the full extent of the tallgrass, mixed-grass, and shortgrass prairie ecological systems of North America plus floristically related plant communities that adjoin and/or interdigitate with the midcontinental grasslands including savanna-open woodland systems, shrub-steppe, and rock outcrop communities. There are 382 plant taxa endemic to the Central Grassland, 300 endemic species (eight of which have multiple subspecific taxa endemic to the region) and 72 endemic subspecies/varieties of more widely distributed species. Nine regional concentrations of endemic taxa were identified and are described as centers of endemism for the Central Grassland: Arkansas Valley Barrens, Edwards Plateau, Llano Estacado Escarpments, Llano Uplift, Mescalero-Monahans Dunes, Niobrara-Platte Tablelands, Raton Tablelands, Red Bed Plains, and Reverchon Rocklands. In addition to hosting localized endemics, these areas are typically enriched with more widely-distributed Central Grassland endemics as well as peripheral or disjunct occurrences of locally-rare taxa, making them regions of high floristic diversity for the Central Grassland. Most of the endemics (299 or 78%) are habitat specialists, associated with rock outcrop, sand, hydric, or riparian habitats. There is a strong correlation between geology and endemism in the Central Grassland, with 59% of the endemics (225 taxa) associated with rock outcrop habitat. Of the 382 Central Grassland endemics, 124 or 33% are of conservation concern (NatureServe ranking of G1/T1 to G3/T3). Of these at-risk taxa, 78 or 63% are primarily associated with one of the centers of endemism identified in the study. It is hoped these findings will be useful in focusing conservation action on the habitats, ecological associations, and regions of the Central Grassland that host the highest concentrations of unique and at-risk plant species and associated biological diversity.
Références
Allison, J.R. & T.E. Stevens. 2001. Vascular flora of the Ketona Dolomite outcrops in Bibb County, Alabama. Castanea 66(1–2):154–205.
Amos, B.B. & C.M. Rowell, Jr. 1988. Floristic geography of woody and endemic plants. In: B.B. Amos & F.R. Gehlbach, eds. Edwards Plateau vegetation: plant ecological studies in central Texas. Baylor University Press, Waco, Texas. U.S.A. Pp. 25–42.
Anderson, D.G. 2006. Mentzelia chrysantha Engelmann ex Brandegee (golden blazingstar): a technical conservation assessment. U.S.D.A. Forest Service, Rocky Mountain Region, Fort Collins, Colorado, U.S.A.
Anderson, R.C. 2006. Evolution and origin of the Central Grassland of North America: Climate, fire, and mammalian grazers. J. Torrey Bot. Soc. 133(4):626–647.
Anderson, R.C. & M.L. Bowles. 1999. Deep-soil savannas and barrens in the Midwestern United States. In: R.C. Anderson, J.S. Fralish, & J.M. Baskin, eds. Savannas, barrens, and rock outcrop communities of North America, Cambridge University Press, New York, U.S.A. and Cambridge, U.K. Pp. 155–170.
Archibold, O.W. 1999. The aspen parkland of Canada. In: R.C. Anderson, J.S. Fralish, & J.M. Baskin, eds. Savannas, barrens, and rock outcrop communities of North America, Cambridge University Press, New York, U.S.A. and Cambridge, U.K. Pp. 406–420.
Armstrong, D.M. 1972. Distribution of mammals in Colorado. Monogr. Mus. Nat. Hist., Univ. Kansas 3:1–415.
Axelrod, D.I. 1985. Rise of the grassland biome, central North America. Bot. Rev. 51(2):163–201.
Barber. S.C. 2008. A floristic study of the vascular plants of the Gypsum Hills and Redbed Plains area of southwestern Oklahoma. Oklahoma Native Pl. Record 8(1):4–36.
Bare, J.E. & R.L. McGregor. 1970. An introduction to the phytogeography of Kansas. Univ. Kansas Sci. Bull. 48(26):869–949.
Barneby, R.C. 1977. Dalea imagines. Mem. New York Bot. Gard. 27:1–892.
Baskin, J.M. & C.C. Baskin. 1988. Endemism in rock outcrop plant communities of unglaciated eastern United States; an evaluation of the roles of edaphic, genetic and light factors. J. Biogeogr. 15:829–840.
Baskin, J.M. & C.C. Baskin. 2000. Vegetation of limestone and dolomite glades in the Ozarks and Midwest regions of the United States. Ann. Missouri Bot. Gard. 87(2):286–294
Beatty, B.L., W.F. Jennings, & R.C. Rawlinson. 2003. Lesquerella arenosa (Richards.) Rydb. var. argillosa Rollins & Shaw (Great Plains bladderpod): A technical conservation assessment. U.S.D.A. Forest Service, Rocky Mountain Region, Fort Collins, Colorado, U.S.A.
Bielmann, A.P. & L.G. Brenner. 1951. The recent intrusion of forests in the Ozarks. Ann. Missouri Bot. Gard. 38:261–282.
Bolen, E.G., L.M. Smith, & H.L. Schramm, Jr. 1989. Playa lakes: Prairie wetlands of the southern High Plains. BioScience 39(9):615–623.
Brennan, L.A. & W.P. Kuvlesky, Jr. 2005. North American grassland birds: An unfolding conservation crisis? J. Wildlife Managem. 69(1):1–13.
Bridges, E.L. & S.L. Orzell. 1986. Distribution patterns of the non-endemic flora of Middle Tennessee limestone glades. ASB Bull. 33:155–166.
Buckallew, R.R. & G.M. Caddell. Vascular flora of the University of Central Oklahoma Selman Living Laboratory, Woodward County, Oklahoma. Proc. Oklahoma Acad. Sci. 83:31–45.
Buchanan, R., ed. 1984. Kansas geology: An introduction to landscapes, rocks, minerals, and fossils. University Press of Kansas, Lawrence, Kansas, U.S.A.
Burge, D.O. (& 13 others). 2016. Plant diversity and endemism in the California Floristic Province. Madroño 63(2):1–206.
Buthod, A.K. & B.W. Hoagland. 2015. Contributions to the flora of Cimarron County and the Black Mesa area. Oklahoma Native Pl. Record 15:49–77.
Caddell, G.M. & K.D. Rice. 2012. Vascular flora of Alabaster Caverns State Park, Cimarron Gypsum Hills, Woodward County, Oklahoma. Oklahoma Native Pl. Record 12:43–62.
Cariveau, A.B. & L. Johnson. 2007 Survey and assessment of playa wetlands in eastern Colorado; Neotropical migratory bird conservation act final report to the U.S. Fish and Wildlife Service, Rocky Mountain Bird Observatory, Brighton, Colorado, U.S.A.
Carr, W.R. 2009. No place but Texas: An annotated list of plant taxa endemic to the Lone Star State (incomplete working draft). The Nature Conservancy of Texas, San Antonio, Texas, U.S.A.
Cartwright, J.M. & W.J. Wolfe. 2016. Insular ecosystems of the southeastern United States: A regional synthesis to support biodiversity conservation in a changing climate. U.S. Geological Survey Professional Paper 1828.
Charboneau, J.L.M., B.E. Nelson, & R.L. Hartman. A floristic inventory of Phillips and Valley counties, Montana (U.S.A.). J. Bot. Res. Inst. Texas 7(2):847–878.
Clark, D.A. 1996. A floristic survey of the Mesa de Maya region, Las Animas, Colorado. Natural History Inventory of Colorado No. 17. University of Colorado Museum, Boulder, Colorado, U.S.A.
Clements, F.E. 1920. Plant indicators: The relation of plant communities to process and practice. Carnegie Institution of Washington Publication 290. Washington, D.C., U.S.A.
Cochrane, T.S. & H.H. Iltis. 2000. Atlas of the Wisconsin prairie and savanna flora. Department of Natural Resources Technical Bulletin No. 191, University of Wisconsin, Madison, Wisconsin, U.S.A.
Colorado Natural Heritage Program. 1997+. Colorado Rare Plant Guide. www.cnhp.colostate.edu. Latest update: June 30, 2014.
Colorado Native Plant Society. 1997. Rare plants of Colorado, 2nd ed. Falcon Press Publishing Company, Inc., Helena, Montana, U.S.A.
Cooper, J.G. 1859. On the distribution of the forests and trees of North America, with notes on its physical geography. In: Annual report to the Board of Regents of the Smithsonian Institution, showing the operations, expenditures, and conditions of the Institution for the year 1858. Washington, D.C., U.S.A. Pp. 246–280.
Correll, D.S. & M.C. Johnston. 1970. Manual of the vascular plants of Texas, Texas Research Foundation, Renner, Texas, U.S.A.
Costea, M., G.L. Nesom, & S. Stefanovic. 2006. Taxonomy of the Cuscuta pentagona complex (Convolvulaceae) in North America. Sida 22(1):151–175.
Cridland, A.A. 1959. The habitat of Aschisma kansanum. Bryologist 62:132–135.
Curtis, J.T. 1959. The vegetation of Wisconsin: An ordination of plant communities. University of Wisconsin Press, Madison, Wisconsin, U.S.A.
Curtis, N.M., Jr., W.E. Ham, & K.S. Johnson. 2008. Geomorphic provinces of Oklahoma. In: K.S. Johnson & K.V. Luza, eds, Earth sciences and mineral resources of Oklahoma. Oklahoma Geological Survey Educational Publication 9, University of Oklahoma, Norman, Oklahoma, U.S.A. Pp. 8.
Decker, K. 2006. Asclepias uncialis Greene (wheel milkweed): A technical conservation assessment. U.S.D.A. Forest Service, Rocky Mountain Region, Fort Collins, Colorado, U.S.A.
Decker, K. 2007. The potential distribution and landscape integrity of Frankenia jamesii (James’ seaheath) in southeastern Colorado. Colorado Natural Heritage Program, Colorado State University, Fort Collins, Colorado, U.S.A.
Diamond, D.D. & F.E. Smeins. 1985. Composition, classification and species response patterns of remnant tallgrass prairies in Texas. Amer. Midl. Naturalist 113(2):294–308.
Diamond, D.D. & F.E. Smeins. 1988. Gradient analysis of remnant True and Upper Coastal Prairie grasslands of North America. Canad. J. Bot. 66:2152–2161.
Diamond, D.D. & F.E. Smeins. 1993. The native plant communities of the Blackland Prairie. In: M.R. Sharpless & J.C. Yelderman, Jr., eds. The Texas Blackland Prairie, land, history, and culture. Baylor University Program for Regional Studies, Waco, Texas, U.S.A. Pp. 66–81.
Dick-Peddie, W.A. 1993. New Mexico vegetation: Past, present, and future. University of New Mexico Press, Albuquerque, New Mexico, U.S.A.
Diffendal, R.F., Jr. 1991. Plate tectonics, space, geologic time, and the Great Plains: A primer for non-geologists. Great Plains Quart. 11(2):83–102.
Diffendal, R.F., Jr. 2017. Great Plains geology. University of Nebraska Press, Lincoln, Nebraska, U.S.A.
Diggs, G.M. & B.L. Lipscomb. 2014. The ferns and lycophytes of Texas. Botanical Research Institute of Texas, Fort Worth, Texas, U.S.A.
Diggs, G.M., Jr., B.L. Lipscomb, & R.J. O’Kennon. 1999. Shinners & Mahler’s illustrated flora of North Central Texas. Sida, Bot. Misc. 16.
Diggs, G.M., Jr., B.L. Lipscomb, M.D. Reed, & R.J. O’Kennon. 2006. Illustrated flora of East Texas, vol. 1. Sida, Bot. Misc. 26.
Dhillion, S.S. & M.H. Mills. 1999. The sand shinnery oak (Quercus havardii) communities of the Llano Estacado: History, structure, ecology, and restoration. In: R.C. Anderson, J.S. Fralish, & J.M. Baskin, eds. Savannas, barrens, and rock outcrop communities of North America, Cambridge University Press, New York, U.S.A. and Cambridge, U.K. Pp. 262–274.
Dorn, R.D. 2001. Vascular plants of Wyoming, 3rd ed. Mountain West Publishing, Cheyenne, Wyoming, U.S.A.
Dorr, L.J. 1990. Revision of the North American genus Callirhoe (Malvaceae). Mem. New York Bot. Gard. 56:1–76.
Dyksterhuis, E.J. 1946. The vegetation of the Fort Worth Prairie. Ecol. Monogr. 16:1–29.
Escudero, A., S. Palacio, F.T. Maestre, & A.L. Luzuriaga. 2014. Plant life on gypsum: A review of its multiple facets. Biol. Rev. 90:1–18.
Estill, J.C. & M.B. Cruzan. 2001. Phytogeography of rare plant species endemic to the southeastern United States. Castanea 66(1–2):3–23.
Evans, C.S. 2010. Playas in Kansas and the High Plains. Kansas Geological Survey Public Information Circular 30. Kansas Geological Survey, University of Kanas, Lawrence, Kansas, U.S.A.
Fenneman, N.M. 1931. Physiography of the western United States. McGraw-Hill, New York, New York, U.S.A.
Fertig, W. 2000. Status review of the Colorado butterfly plant (Gaura neomexicana ssp. coloradensis).Unpublished report prepared for the Wyoming Cooperative Fish and wildlife Research Unit, U.S. Fish and Wildlife Service, and Wyoming Game and Fish Department by theWyoming Natural Diversity Database, Laramie, Wyoming, U.S.A.
Flora of North America Editorial Committee, eds. [FNAEC] 1993–. Flora of North America north of Mexico. 18+ vols. Oxford University Press, New York, U.S.A. and Oxford, U.K.
Flores, D. 2010. Caprock Canyonlands: Journeys into the heart of the southern plains, 20th anniversary ed. Texas A. & M. University Press, College Station, Texas, U.S.A.
Foti, T.L. & G.A. Bukenhofer. 1998. A description of the sections and subsections of the Interior Highlands of Arkansas and Oklahoma. J. Arkansas Acad. Sci. 52:53–62.
Foti, T.L., S. Simon, D. Zollner, & M. Hattenbach. 2003. Blackland prairie landscapes of southwestern Arkansas: Historical perspective, present status, and restoration potential. In: E. Peacock & T. Schauwecker, eds. Blackland prairies of the Gulf Coastal Plain. University of Alabama Press, Tuscaloosa, Alabama, U.S.A. Pp. 94–109.
Foti, T. & C.T. Witsell. 2013. Effects of physical factors on the distribution of native flora and vegetation in the Natural Divisions of Arkansas. In: J.L. Gentry, G.P. Johnson, B.T. Baker, C.T. Witsell, & J.D. Ogle, eds. Atlas of the vascular plants of Arkansas, Arkansas Vascular Flora
Committee, Fayetteville, Arkansas, U.S.A. Pp. 17–40.
Fowler, N.L. & D.W. Dunlap. 1986. Grassland vegetation of the eastern Edwards Plateau. Amer. Midl. Nat. 115(1):146–155.
Gage, A.M., S.K. Olimb, & J. Nelson. 2016. Plowprint: Tracking cumulative cropland expansion to target grassland conservation. Great Plains Res. 26(2):107–116.
Gentry, J.L., G.P. Johnson, B.T. Baker, C.T. Witsell, & J.D. Ogle, eds. 2013. Atlas of the vascular plants of Arkansas, Arkansas Vascular Flora Committee, Fayetteville, Arkansas, U.S.A.
Graves, G.R. 2016. First record of Clematis fremontii S. Watson from Arkansas. Castanea 81(4):333–335.
Great Plains Flora Association [GPFA]. 1977. Atlas of the flora of the Great Plains. Iowa State University Press, Ames, Iowa, U.S.A.
Great Plains Flora Association [GPFA]. 1986. Flora of the Great Plains. University Press of Kansas, Lawrence, Kansas, U.S.A.
Griffith, G.E., S.A. Bryce, J.M. Omernik, J.A. Comstock, A.C. Rogers, B. Harrison, S.L. Hatch, & D. Bezanson. 2004. Ecoregions of Texas, U.S. Environmental Protection Agency, Corvallis, Oregon, U.S.A., 1:2,500,000.
Hanberry, B.B., D.T. Jones-Farraand, & J.M. Kabrick. 20014. Historical open forest ecosystems in the Missouri Ozarks: Reconstruction and restoration targets. Ecol. Res. 32(4):407–416.
Handley, J & W. Fertig. 2002. Cuscuta plattensis Wyoming dodder. State species abstract, Wyoming Natural Diversity Database, University of Wyoming, Laramie, Wyoming, U.S.A.
Hardy, J.P. 1991. The vascular flora of Banner County, Nebraska. Trans. Nebraska Acad. Sci. 18:109–126.
Harms, R. T. 2014. A new species of Evolvulus (Convolvulaceae) from the High Plains of the Texas/New Mexico border. Phytoneuron 2014-20:1–20.
Hattin, D.E. 1975. Stratigraphy and depositional environments of Greenhorn Limestone (Upper Cretaceous) of Kansas. Kansas Geol. Survey Bull. 209.
Hattin, D.E. 1982. Stratigraphy and depositional environment of Smoky Hill Chalk Member, Niobrara Chalk (Upper Cretaceous) of the type area, western Kansas. Kansas Geol. Survey Bull. 225.
Haukos, D.A. & L.M. Smith. 1997. Common flora of the playa lakes. Texas Tech University Press, Lubbock, Texas, U.S.A.
Hazlett, D.L. 1998. Vascular plant species of the Pawnee National Grassland. Gen. Tech. Rep RMRS-GTR-17, U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fort Collins, Colorado, U.S.A.
Hazlett, D.L. 2004. Vascular plant species of the Comanche National Grasslands in southeastern Colorado. Gen. Tech. Rep. RMRS-GTR-130. U.S. Department of Agriculture Forest Service, Rocky Mountain Research Station, Fort Collins, Colorado, U.S.A.
Hazlett, D.L., M.H. Schiebout, & P.L. Ford. 2009. Vascular plants and a brief history of the Kiowa and Rita Blanca National Grasslands. Gen. Tech. Rep. RMRSGTR-233. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fort Collins, Colorado, U.S.A.
Heidel, B. 2012. Status of Penstemon haydenii (Blowout Penstemon) in Wyoming. 2012. Prepared for Bureau of Land Management—Rawlins and Rock Springs Field Offices and Wyoming State Office. Wyoming Natural Diversity Database, University of Wyoming, Laramie, Wyoming. U.S.A.
Heidel, B. & J. Handley. 2004. Parthenium alpinum (Nutt.) Torr. & Gray (alpine feverfew): A technical conservation assessment. U.S.D.A. Forest Service, Rocky Mountain Region, Fort Collins, Colorado, U.S.A.
Heil, K.D., S.L. O’Kane, Jr., L.M. Reeves, & A. Clifford. 2013. Flora of the Four Corners region: Vascular plants of the San Juan River drainage, Arizona, Colorado, New Mexico, and Utah. Missouri Botanical Garden Press, St. Louis, Missouri, U.S.A.
Henwood, W.D. 2010. Toward a strategy for the conservation and protection of the world’s temperate grasslands. Great Plains Res. 20(1):121–134.
Hill, R.T. 1901. Geography and geology of the Black and Grand Prairies, Texas. U.S. Geological Survey. Annual Report 21. United States Geological Survey, Washington, D.C., U.S.A.
Hoagland, B.W. 2000. The vegetation of Oklahoma: A classification of landscape mapping and conservation planning. Southw. Nat. 45:385–420.
Hoagland, B.W. & A.K. Buthod. 2005. Vascular flora of a gypsum dominated site in Major County, Oklahoma. Proc. Okla. Acad. Sci. 85:1–8.
Hoagland, B.W., I.H. Butler, F.L. Johnson, & S. Glenn. 1999. The Cross Timbers. In: R.C. Anderson, J.S. Fralish, & J.M. Baskin, eds. Savannas, barrens, and rock outcrop communities of North America, Cambridge University Press, New York, U.S.A. and Cambridge, U.K. Pp. 231–245.
Hoagland, B.W. & S.L. Collins 1997. Heterogeneity in shortgrass prairie vegetation; the role of playa lakes. J. Veg. Sci. 8:277–286.
Hoagland, B.W. & F.L. Johnson. 2001. Vascular flora of the Chickasaw National Recreation Area, Murray County, Oklahoma. Castanea 66(4):383–400.
Hoekstra, J.M., T.M. Boucher, T.H. Ricketts, & C. Roberts. 2005. Confronting a biome crisis: Global disparities of habitat loss and protection. Ecol. Lett. 8:23–29.
Hood, H.C. & J.R. Underwood, Jr. 2001. Geology of Palo Duro Canyon. In: D.F. Guy, ed. The story of Palo Duro Canyon. Texas Tech University Press, Lubbock, Texas, U.S.A. Pp. 3–34.
Holliday, V.T. 2001. Stratigraphy and geochronology of upper Quaternary eolian sand on the Southern High Plains of Texas and New Mexico, United States. GSA Bull. 113(1):88–108.
Horn, D.D. & J. Shaw. 2007. Noteworthy collections: Tennessee. Castanea 72(1):48–49.
Hunt. C.B. 1974. Natural regions of the United States and Canada. W.H. Freeman, San Francisco, California, U.S.A.
Jercinovic, E. 2007. The status of genus Chamaesyce in New Mexico. New Mexico Botanist 40:1–14.
Johnson, A.F., W.W. Baker, L.C. Anderson, & A.K. Gholson, Jr. 2013. Flora of calcareous upland glades in Gadsen and Jackson counties, Florida. J. Bot. Res. Inst. Texas 7(1):475–494.
Johnston, M.C. 1969. Polygonum texense M.C. Johnston (Polygonaceae), new species from South Plains and Edwards Plateau. Southw. Nat. 14(2):257–258.
Kartesz, J.T. 2015. North American Plant Atlas. (http://bonap.net/napa). 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)]
Kaul, R.B., D. Sutherland, & S. Rolfsmeier. 2011. The flora of Nebraska, 2nd ed. School of Natural Resources, University of Nebraska-Lincoln, Lincoln, Nebraska, U.S.A.
Kelso, S., C. Hall, & G. Maentz. 2001. The role of landscape anomalies in regional plant conservation. In: J. Maschinski & L. Holter, eds. Southwestern rare and endangered plants: Proceedings of the third conference; 2000 September 25–28; Flagstaff, Arizona. RMRS-P-23. U.S. Department of Agriculture, Forest Service, Fort Collins, Colorado, U.S.A. Pp. 13–19.
Kelso, S., K. Heckman, J. Lawton, & G. Maentz. 1996. Endemic calciphiles of the Middle Arkansas Valley, Colorado. In: J. Maschinski, H.D. Hammond, & L. Holter, eds. Southwestern rare and engendered plants: Proceedings of the second conference; 1995 September 11–14, Flagstaff, Arizona. Gen. Tech. Rep. RM-GTR-283, U.S. Department of Agriculture, Forest Service, Fort Collins, Colorado, U.S.A. Pp. 270–280.
Kelso, S., N. Bower, K.E. Heckmann, P.M. Beardsley, & D.G. Greve. 2003. Geobotany of the Niobrara Chalk Barrens in Colorado: A study of edaphic endemism. W. N. Amer. Naturalist 63(3):299–313.
Kelso, T., N. Bower, P. Halteman, K. Tenney, & S. Weaver. 2007. Dune communities of SE Colorado: Patterns of rarity, disjunction and succession. In: P. Barlow-Irick, J. Anderson, C. McDonald, eds. Southwestern rare and engendered plants: Proceedings of the fourth conference; 2004 March 22–26, Las Cruces, New Mexico. RMRS-P-48CD, U.S. Department of Agriculture, Forest Service, Fort Collins, Colorado, U.S.A. Pp. 39–48.
Knight. D.H. 1994. Mountains and plains: The ecology of Wyoming landscapes. Yale University Press, New Haven, Connecticut, U.S.A.
Knight, D.H. 1999. Ponderosa and limber pine woodlands. In: R.C. Anderson, J.S. Fralish, & J.M. Baskin, eds. Savannas, barrens, and rock outcrop communities of North America, Cambridge University Press, New York, U.S.A. and Cambridge, U.K. Pp. 249–261.
Kraft, N.J.B., B.G. Baldwin, & D.D. Ackerly. 2010. Range size, taxon age and hotspots of neoendemism in the California flora. Diversity & Distrib. 16:403–413.
Kruckeberg, A.R. 1986. An essay: The stimulus of unusual geologies for plant speciation. Syst. Bot. 11:455–463.
Kruckeberg. A.R. 2002. Geology and plant life: The effects of landforms and rock types on plants. University of Washington Press, Seattle, Washington, U.S.A.
Kruckeberg, A.R. & D. Rabinowitz. 1985. Biological aspects of endemism in higher plants. Ann. Rev. Ecol. Syst. 16:447–479.
Kuchler, A.W. 1985. Potential natural vegetation of the conterminous United States [map], revised. American Geographical Society, New York, New York, U.S.A.
Kuhn, B., B.E. Nelson, & R.L. Hartman. 2011. A floristic inventory of the Cimarron National Grassland (Kansas) and the Comanche National Grassland (Colorado). J. Bot. Res. Inst. Texas 5(2):753–772.
Ladyman, J.A.R. 2005. Oenothera harringtonii Wagner, Stockhouse & Klein (Colorado Springs evening primrose): A technical conservation assessment. U.S.D.A. Forest Service, Rocky Mountain Region, Fort Collins, Colorado, U.S.A.
Ladyman, J.A.R. 2006a. Astragalus barrii Barneby (Barr’s milkvetch): A technical conservation assessment. U.S.D.A. Forest Service, Rocky Mountain Region, Fort Collins, Colorado, U.S.A.
Ladyman, J.A.R. 2006b. Chenopodium cycloides A. Nelson (sandhill goosefoot): A technical conservation assessment. U.S.D.A. Forest Service, Rocky Mountain Region, Fort Collins, Colorado, U.S.A.
Ladyman, J.A.R. 2006c. Eriogonum visheri A. Nelson (Visher’s buckwheat): A technical conservation assessment. U.S.D.A. Forest Service, Rocky Mountain Region, Fort Collins, Colorado, U.S.A.
Lauenroth, W.K., I.C. Burke, & M.P. Gutmann. 1999. The structure and function of ecosystems in the central North American grassland region. Great Plains Res. 9(2):223–259.
Lavin, M. & C. Seibert. 2011. Great Plains flora? Plant geography of eastern Montana’s lower elevation shrub-grass dominated vegetation. In: C.L. Wambolt et al., comps. 15th wildland shrub symposium – Shrublands: Wildlands and wildlife habitats, 2008 June 17–19, Bozeman, Montana. Natural Resources and Environmental Issues vol. 16, article 1, Utah State University, Logan, Utah, U.S.A.
Lawless, P.J., J.M. Baskin, & C.C. Baskin. 2006. Xeric limestone prairies of Eastern United States: Review and synthesis. Bot. Rev. 72(3):235–272.
Lee, W.T. 1902. The canyons of southeastern Colorado. J. Geogr. 1(8):357–370.
Lee, W.T. 1903. The canyons of northeastern New Mexico. J. Geogr. 2(2):63–82.
Lee, W.T. 1912. Extinct volcanoes of northeast New Mexico. Amer. Forest. 18(6):357–365.
Lesica, P. 2012. Manual of Montana vascular plants. Botanical Research Institute of Texas, Fort Worth, Texas, U.S.A.
Llado, L. & M.C. Slatterly. 2015. Fine scale temporal variations of surface moisture in topographically controlled Muhly grass seeps. Ecohydrology 9(3):371–381.
Locklear, J.H. 1989. The status of Ambrosia linearis (Rydb.) Payne in Colorado. Report to the U.S. Fish and Wildlife Service Endangered Species Office, Denver, Colorado, U.S.A.
Locklear, J.H. 1990. A Colorado specialty: Ambrosia linearis. Aquilegia [Colorado Native Pl. Soc. Newsl.] 14(5):10–11.
Locklear, J.H. 2011. Phlox: A natural history and gardener’s guide. Timber Press, Portland, Oregon, U.S.A.
Locklear, J.H. 2014. Reconnaissance survey of rock outcrop communities in the Kimball Grasslands of Nebraska. Prepared for the Nebraska Natural Heritage Program, Nebraska Game and Parks Commission, Lincoln, Nebraska, U.S.A.
Longing, S., S. Discua, & J. Cokendolpher. 2014. Surveys and habitat assessment of endemic insects at the Monahans dune system. Final report prepared for the Texas Parks and Wildlife Department, Texas Tech University, Lubbock, Texas, U.S.A.
Looman, J. & K.F. Best. 1987. Budd’s flora of the Canadian Prairie Provinces. Research Branch Agriculture Canada Publication 1662.
MacRoberts, B.R., M.H MacRoberts, C.S. Reid, & P.L. Faulker, 2009. Vascular flora of Morse Clay prairies in northwestern Louisiana. J. Bot. Res. Inst. Texas 3(1):355–366.
MacRoberts, B.R., M.H. MacRoberts, & C.T. Witsell. 2011. Small-scale vascular plant species richness in southwestern Arkansas blackland prairies. J. Bot. Res. Inst. Texas 5(2):743–751.
MacRoberts, M.H., B.R. MacRoberts, & L.S. Jackson. 2003. Louisiana prairies. In: E. Peacock & T. Schauwecker, eds. Blackland prairies of the Gulf Coastal Plain. University of Alabama Press, Tuscaloosa, Alabama, U.S.A. Pp. 80–93.
MacRoberts, M.H. B.R. MacRoberts, B.A. Sorrie, & R.E. Evans. 2002. Endemism in the West Gulf Coastal Plain; importance of xeric habitats. Sida 20(2):767–780.
Mahler, H.D., Jr., G.F. Engelmann, & R.D. Shuster. 2003. Roadside geology of Nebraska. Mountain Press Publishing Company, Missoula, Montana, U.S.A.
McMillan, M.E., C.L. Angevine, & P.L. Heller. 2002. Postdepositional tilt of the Miocene-Pliocene Ogallala group on the western Great Plains: Evidence of late Cenozoic uplift of the Rocky Mountains. Geology 30(1):63–66.
Menges, E.S. 1999. Ecology and conservation of Florida Scrub. In: R.C. Anderson, J.S. Fralish, & J.M. Baskin, eds. Savannas, barrens, and rock outcrop communities of North America, Cambridge University Press, New York, U.S.A. and Cambridge, U.K. Pp. 7–22.
Mink, J.N., J.R. Singhurst, & W.C. Holmes. 2012. A new species of Hymenoxys (Asteraceae, Helenieae, Tetraneuridinae) from Texas. Novon 22:56–59.
Mohr, C. 1901. Plant life of Alabama. Contr. U.S. Natl. Herb. 6:1–921.
Moir, W.H. 1969. Steppe communities in the foothills of the Colorado Front Range and their relative productivities. Amer. Midl. Naturalist 81:331–340.
Mueggler, W.F. & W.L. Stewart. 1980. Grassland and shrubland habitat types of western Montana. Gen. Tech. Rep Int-66, U.S. Department of Agriculture, Forest Service, Intermountain Forest and Range Experimental Station, Ogden, Utah, U.S.A.
Muhs, D.R. & V.T. Holliday. 1995. Evidence of active dune sand on the Great Plains in the 19th century from accounts of early explorers. Quaternary Res. 43:198–208.
Muhs, D.R. & V.T. Holliday. 2001. Origin of late Quaternary dune fields on the Southern High Plains of Texas and New Mexico. Bull. Geol. Soc. Amer. 113(1):75–87.
Naumann, T.S. 1991. Status report for Frasera coloradensis. Unpublished report prepared for the Colorado Natural Areas Program, Denver, Colorado, U.S.A.
Neely, B., S. Panjabi, & J. Handwerk. 2011. Arkansas Valley Barrens: Conservation action plan 2011 update. The Nature Conservancy and the Colorado Natural Heritage Program, Colorado State University, Fort Collins, Colorado, U.S.A.
Neid, S., K. Decker, J. Handwerk, & S.S. Panjabi. 2007. Rare plant surveys on the Piñon Canyon Maneuver Site 2006–2007. Colorado Natural Heritage Program, Colorado State University, Fort Collins, Colorado, U.S.A.
Neid, S. & J. Handwerk, 2007. Rare plant surveys on Fort Carson 2006–2007. Colorado Natural Heritage Program, Colorado State University, Fort Collins, Colorado, U.S.A.
Nelson, A. 1899. New plants from Wyoming VI. Bull. Torrey Bot. Club 26:122–134.
Nelson, P.W. 2005. The terrestrial natural communities of Missouri, revised ed. The Missouri Natural Areas Committee, Jefferson City, Missouri, U.S.A.
Nelson, P. & D. Ladd. 1980. Preliminary report on the identification, distribution, and classification of Missouri glades. In: C. Kucera, ed. Proceedings of the seventh North American Prairie conference, Southwest Missouri State University, Springfield, Missouri, U.S.A. Pp. 59–76.
Nesom, G.L. & T.K. Lowrey. 2011. Solidago capulinensis (Asteraceae: Astereae) redividus. Phytoneuron 2011-24:1–22.
Nesom, G.L. & R.J. O’Kennon. 2001. Two new species of Liatris series Punctatae (Asteraceae: Eupatorieae) centered in North Central Texas. Sida 19:767–787.
Nesom, G.L. & R. J. O’Kennon. 2008. Major plant communities of Lake Meredith National Recreational Area and Alibates Flint Quarries National Monument. Phytologia 90(3):391–401.
New Mexico Rare Plant Technical Council. 1999. New Mexico Rare Plants. Albuquerque, NM: New Mexico Rare Plants Home Page. http://nmrareplants.unm.edu (Latest update: 21 July 2016).
Noss, R.F. 2013. Forgotten grasslands of the South: Natural history and conservation. Island Press, Washington, D.C., U.S.A.
Noss, R.F., W.J. Platt, B.A. Sorrie, A.S. Weakley, D.B. Means, J. Costanza, & R.K. Peet. 2014. How global biodiversity hotspots may go unrecognized; lessons from the North American Coastal Plain. Diversity Distrib. 21:236–244.
Nuzzo, V. 1986. Extent and status of Midwest oak savanna: Presettlement and 1985. Natural Areas J. 6:6–36.
O’Kennon, R.J. & K.N. Taylor. 2015. Cyperus granitophilus (Cyperaceae), a granite outcrop endemic, new for Texas and Oklahoma (U.S.A.). J. Bot. Res. Inst. Texas 9(1):251–257.
Peterson, R.S. & C.S. Boyd. 1998. Ecology and management of sand shinnery communities: A literature review. Gen. Tech. Rep RMRS-GTR-16, U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fort Collins, Colorado, U.S.A.
Poole, J.M. W.R. Carr, D.M. Price, & J.R. Singhurst. 2007. Rare plants of Texas. Texas A & M University Press, College Station, Texas, U.S.A.
Pringle, J.S. & T. Witsell. 2005 A new species of Sabatia (Gentianaceae) from Saline County, Arkansas. Sida 21(3):1249–1262.
Raduski, A.R., L.H. Rieseberg, & J.L. Strasburg. 2010. Effective population size, gene flow, and species status in a narrow endemic sunflower, Helianthus neglectus, compared to its widespread sister species, H. petiolaris. Int. J. Mol. Sci. 11:492–506.
Ramaley, F. 1939. Sand-hill vegetation of northeastern Colorado. Ecol. Monogr. 9(1):1–51.
Ravin, P.H., & D.I. Axelrod. 1978 (reprinted 1995). Origins and relationships of the California flora. California Native Plant Society, Sacramento, California, U.S.A.
Reeves, C.C., Jr. 1972. Tertiary-Quaternary stratigraphy and geomorphology of West Texas and southeastern New Mexico. In: V.C. Kelly & F.D. Trauger, eds. East-central New Mexico, New Mexico Geological Survey 23rd annual fall field conference guidebook. New Mexico Geological Society, Socorro, New Mexico, U.S.A. Pp. 108–117.
Reid, C.S., P.L. Faulkner, M.H. MacRoberts, B.R. MacRoberts, & M. Bordelon. 2010. Vascular flora and edaphic characteristics of saline prairies in Louisiana. J. Bot. Res. Inst. Texas 4(1):357–379.
Riskind, D.H. & D.D. Diamond. 1988. An introduction to environments and vegetation. In: B.B. Amos & F.R. Gehlbach, eds. Edwards Plateau vegetation: Plant ecological studies in central Texas. Baylor University Press, Waco, Texas. U.S.A. Pp. 1–15.
Robinson, H.W. and C.T. McAllister. 2012. The endemic biota of Oklahoma. Proc. Okla. Acad. Sci. 92:21–28.
Rohrer, W.L. 1997. Biosystematic study of the rare plant Paronychia virginica Sprengel (Caryophyllaceae) employing morphometric and allozyme analyses. MS thesis. Virginia Polytechnic Institute and State University, Blacksburg, Virginia, U.S.A.
Rogers, C.M. 1953. The vegetation of the Mesa de Maya region of Colorado, New Mexico, and Oklahoma. Lloydia 16(4):257–290.
Rogers, C.M. 1954. Some botanical studies in the Black Mesa region of Oklahoma. Rhodora 56:205–212.
Rolfsmeier, S.B. & G. Steinauer. 2010. Terrestrial ecological systems and natural communities of Nebraska. Nebraska Natural Heritage Program, Nebraska Game and Parks Commission, Lincoln, Nebraska, U.S.A.
Rowell, C.M., Jr. 1967. Vascular plants of the Texas Panhandle and South Plains. PhD diss. Oklahoma State University, Stillwater, Oklahoma, U.S.A.
Rowell, C.M., Jr. 1971. Vascular plants of the playa lakes of the Texas Panhandle and South Plains. Southw. Nat. 15(4):407–417.
Rydberg, P.A. 1917. Flora of the Rocky Mountains and adjacent plains. Published by the author, New York, New York, U.S.A.
Rydberg, P.A. 1931. A short phytogeography of the prairies and Great Plains of central North America. Brittonia 1:57–66 + plate.
Rydberg, P.A. 1932. Flora of the prairies and plains of central North America. New York Botanical Garden, New York, New York, U.S.A.
Saghatelyan, A.A. 2015. Phytogeographical relationships and analysis of the flora of south-central Texas, U.S.A. J. Bot. Res. Inst. Texas 9(1):259–294.
Schiebout, M.H., D.L. Hazlett, & N. Snow. 2008. Floristic survey of the vascular plants over parts of northeastern New Mexico. J. Bot. Res. Inst. Texas 2(2):1407–1447.
Schroeder, W.A. 1982. Presettlement prairie of Missouri, 2nd ed. Natural History Series No. 2, Missouri Department of Conservation, Jefferson City, Missouri, U.S.A.
Schulz, K.A. & R.B. Shaw. 1992. Status of Haplopappus fremontii A. Gray ssp. monocephalus (A. Nelson) Hall [Asteraceae] in Colorado. Prairie Naturalist 24(3):143–148.
Scott, G.R. & W.A. Cobban. 1964. Stratigraphy of the Niobrara Formation at Pueblo, Colorado. U.S. Geological Survey Professional Paper 454-L.
Shaw, R.B., S.L. Anderson, K.A. Schultz, & V.E. Diersing. 1989a. Plant communities, ecological checklist, and species list for the U.S. Army Piñon Canyon Maneuver Site, Colorado. Range Science Series 37. Department of Range Science, Colorado State University, Fort Collins, Colorado, U.S.A.
Shaw, R.B., S.L. Anderson, K.A. Schultz, & V.E. Diersing. 1989b. Floral inventory for the U.S. Army Piñon Canyon Maneuver Site, Colorado. Phytologia 67:1–42.
Shultz, Leila M. 1993. Patterns of endemism in the Utah flora. In: R. Sivinski & K. Lightfoot, eds. Southwestern rare and endangered plants. New Mexico Department of Forestry and Resources Conservation Division, Misc. Publ. No. 2. Santa Fe, New Mexico, U.S.A. Pp. 249–263.
Shorthouse, J.D. 2010. Ecoregions of Canada’s prairie grasslands. In: J.D. Shorthouse & K. D. Floate, eds. Arthropods of Canadian grasslands, vol. 1: Ecology and interactions in grassland habitats. Pp. 53–81.
Sims, P.L. & P.G. Risser, 2000. Grasslands. In: M.G. Barbour & W.D. Billings, eds. North American terrestrial vegetation, 2nd ed. Cambridge University Press, New York, U.S.A. and Cambridge, U.K. Pp. 323–356.
Singh, J.S., W.K. Laurenroth, R.K. Heitchmidt, & J.L. Dodd. 1983. Structural and functional attributes of the vegetation of the mixed prairie of North America. Bot. Rev. 49(1):117–149.
Singhurst, J.R., L.L. Sanchez, D. Frels, Jr., T.W. Schwertner, M. Mitchell, S. Moren, & W.C. Holmes. 2007. The vascular flora of Mason Mountain Wildlife Management Area, Mason County, Texas. S. E. Naturalist 6(4):683–692
Sivinski, R.C. & P.J. Knight. 1996. Narrow endemism in the New Mexico flora. In: J. Maschinski, H.D. Hammond, & L. Holter, eds. Southwestern rare and engendered plants: Proceedings of the second conference; 1995 September 11–14, Flagstaff, Arizona. Gen. Tech. Rep. RM-GTR-283, U.S. Department of Agriculture, Forest Service, Fort Collins, Colorado, U.S.A. Pp. 286–296.
Smith, B.A. 2010. Four western Cheilanthoid ferns in Oklahoma. Oklahoma Native Pl. Rec. 10:65–70.
Smith, E.B. 1981. New combinations in Croptilon (Compositae-Astereae). Sida 9(1):59–63.
Smith, H.L. 1966. Mosses of the Great Plains and Arkansas River lowlands of Kansas. Univ. Kansas Sci. Bull. 46(12):433–474.
Smith, J.P. & J.O. Sawyer. 1988. Endemic vascular plants of northwestern California and southwestern Oregon. Madrono 35:54–69.
Smith, L.M. 2003. Playas of the Great Plains. University of Texas Press, Austin, Texas, U.S.A.
Snow, N. 1990. The distribution of Frankenia jamesii Torr. ex Gray (Frankeniaceae) in the Great Plains. Prairie Nat. 22(3):211–214.
Sorrie, B.A. & A.S. Weakley. 2001. Coastal Plant vascular plant endemics: Phytogeographic patterns. Castanea 66(1–2):50–82.
Spearing, D. 1991. Roadside geology of Texas. Mountain Press Publishing Company, Missoula, Montana, U.S.A.
Spellenberg, R.W. 1993. Species of special concern. In: W.A. Dick-Peddie. New Mexico vegetation: Past, present, and future. University of New Mexico Press, Albuquerque, New Mexico, U.S.A. Pp. 179-224.
Springer, T.L. & R.J. Tyrl. 1989. Distribution, habitat, and reproductive biology of Phlox oklahomensis Wherry (Polemoniaceae). Proc. Okla. Acad. Sci. 69:15–21.
Stebbins, G.L. & J. Major. 1965. Endemism and speciation in the California flora. Ecol. Monogr. 35:1–35.
Stephens, A.R. & W.M. Holmes. 1989. Historical atlas of Texas. University of Oklahoma Press, Norman, Oklahoma, U.S.A.
Shure, D.J. 1999. Granite outcrops of the southeastern United States. In: R.C. Anderson, J.S. Fralish, & J.M. Baskin, eds. Savannas, barrens, and rock outcrop communities of North America, Cambridge University Press, New York, U.S.A. and Cambridge, U.K. Pp. 99–118.
Swadek, R.K. 2012. Phemaranthus calcaricus (Montiaceae) new to Texas. J. Bot. Inst. Texas 6(10):303–307.
Swadek, R.K. & T.L. Burgess. 2012. The vascular flora of the North Central Texas Walnut Formation. J. Bot. Res. Inst. Texas 6(2):725–752.
Swinehart, J. B., V. L. Souders, H. M. DeGrew, and R. F. Diffendal, Jr. 1985. Cenozoic paleogeography of western Nebraska. In: R.M. Flores and S.S. Kaplan, eds. Ceonzoic paleogeography of the west-central United States. Rocky Mountain Paleogeography Symposium 3, Society of Economic Paleontologists and Mineralogists, Rocky Mountain Section, Denver, Colorado. U.S.A. Pp. 209 – 229.
Takhtajan, A.L. 1986. Floristic regions of the world. University of California Press, Berkeley, California, U.S.A.
Taylor, K.N. & R.J. O’Kennon. 2013. Ecology and distribution of the North Central Texas endemic Dalea reverchonii (Fabaceae). J. Bot. Res. Inst. Texas 7(1):603–610.
Taylor, K.N. & R.J. O’Kennon. 2014. Expanded distribution of Gratiola quartermaniae (Plantaginaceae) in Texas, U.S.A. J. Bot. Res. Inst. Texas 8(1):333–337.
Taylor, K.N. & R.J. O’Kennon. 2016. The vascular flora of Enchanted Rock State Natural Area, Llano and Gillespie counties, Texas, U.S.A. J. Bot. Res. Inst. Texas 10(1):267–294.
Taylor, K.N., R.J. O’Kennon, & T.F. Rehman. 2012. Expanded distribution of Isoetes butleri (Isoetaceae) in Texas. J. Bot. Res. Inst. Texas 6:753–757.
Terletzky, P. A. & O.W. Van Auken. 1996. Comparison of cedar glades and associated woodlands of the southern Edwards Plateau. Texas J. Sci. 48(1):55–67.
Terrell, E.E. 1986. Taxonomic and nomenclatural notes on Houstonia nigricans (Rubiaceae). Sida 11:471–481.
Thorne, J.H., J.H. Viers, J. Price, & D.M. Stoms. 2009. Spatial patterns of endemic plants in California. Nat. Areas J. 29(4):344–366.
Thorne, R.F. 1993. Phytogeography. In: Flora of North America Editorial Committee, ed. Flora of North America north of Mexico, vol. 1. Oxford University Press, New York, U.S.A. and Oxford, U.K. Pp. 132–153.
Transeau, E.N. 1935. The prairie peninsula. Ecology 16:423–427.
Trock, D.K. & R.J. O’Kennon. 2003. A new species of Packera (Asteraceae: Senecioneae) from the Edwards Plateau of Texas. Sida 20(3):945–951.
Turner, B.L. 1959. The legumes of Texas. University of Texas Press, Austin, Texas, U.S.A.
Turner, B.L. 1993. Texas species of Mirabilis (Nyctaginaceae) Phytologia 75(6):432–451.
Turner, B.L. 1995. Taxonomic overview of Hedyotis nigricans (Rubiaceae) and closely allied taxa. Phytologia 79(1):12–21.
Turner, B.L. 1997. Rebuttal to Terrell’s taxonomic notes of Turner’s treatment of Texan and Mexican Hedyotis. Phytologia 82:82–85.
Turner, B.L. 2006. Dalea austrotexana (Fabaceae), a new species from southernmost Texas. Phytologia 88(3):288–293.
Turner, B.L. 2009. Iva corbinii (Asteraceae): A remarkable new species from Travis County, Texas. Lundellia 12:5–7
Turner, B.L. 2012a. A new species of Cardamine (Brassicaceae) from south-central Texas. Phytoneuron 2012-49:1–5.
Turner, B.L. 2012b. Taxonomy of Eucnide bartonioides (Loaseae) complex in Texas. Phytologia 94(3):305–309.
Turner, B.L. 2014 Taxonomic overview of Eustoma (Gentianaceae). Phytologia 96(1):7–11.
Turner, B.L. & M.J. Moore. 2014. Oenothera gayleana (Oenothera sect. Calylophus, Onagraceae), a new gypsophile from Texas, New Mexico, and Oklahoma. Phytologia 96(3):200–206.
Turner, B.L., H. Nichols, G.C. Denny, & O. Doron. 2003. Atlas of the vascular plants of Texas. Sida, Bot. Misc. 24.
Turner, M.W. 2003. A new species of Brazoria (Lamiaceae) from the Central Mineral Region of Texas. Sida 20(4):1565–1571.
Van Auken, O.W. 2000. Characteristics of intercanopy bare patches in Juniperus woodlands of the southern Edwards Plateau, Texas. Southw. Naturalist 45(2):95–110.
Walters, T.W. & R. Wyatt. 1982. The vascular flora of granite outcrops in the Central Mineral Region of Texas. Bull. Torrey Bot. Club 109(3):344–364.
Ware, S. 2002. Rock outcrop communities (glades) in the Ozarks: A synthesis. Southw. Naturalist 47(4):585–597.
Weakley, A.S., J.C. Ludwig, & J.F. Townsend. 2012. Flora of Virginia. Botanical Research Institute of Texas, Fort Worth, Texas, U.S.A.
Weaver, J.E. 1954. North American prairie. Johnsen Publishing Company, Lincoln, Nebraska, U.S.A.
Weber, W.A. & R.C. Wittmann. 1992. Catalog of the Colorado flora: A biodiversity baseline. University Press of Colorado, Boulder, Colorado, U.S.A.
Weber, W.A. & R.C. Wittmann. 2012. Colorado flora, eastern slope: A field guide to the vascular plants, 4th ed. University Press of Colorado, Boulder, Colorado, U.S.A.
Wells, P.V. 1970. Historical factors controlling vegetation patterns and floristic distributions in the Central Plains region of North America. In: W. Dort, Jr. & J. K. Jones, eds. Pleistocene and Recent environments of the central Great Plains, University of Kansas Department of Geology Special Publication No. 3, University Press of Kansas, Lawrence, Kansas, U.S.A. Pp. 211–221.
West, N.E. 1999. Juniper-pinon savannas and woodlands of western North America. In: R.C. Anderson, J.S. Fralish, & J.M. Baskin, eds. Savannas, barrens, and rock outcrop communities of North America, Cambridge University Press, New York, U.S.A. and Cambridge, U.K. Pp. 288–308.
Whitehouse, E. 1933. Plant succession on central Texas granite. Ecology 14(4):391–405.
Will-Wolf, S. & F. Stearns. 1999. Dry soil oak savanna in the Great Lakes region. In: R.C. Anderson, J.S. Fralish, & J.M. Baskin, eds. Savannas, barrens, and rock outcrop communities of North America, Cambridge University Press, New York, U.S.A. and Cambridge, U.K. Pp. 135–154.
World Wildlife Fund. 2016. Plowprint annual report 2016. World Wildlife Fund Northern Great Plains Program, Bozeman, Montana, U.S.A.
Wright, R.A. 2001. The vegetation of Palo Duro Canyon. In: D.F. Guy, ed. The story of Palo Duro Canyon. Texas Tech University Press, Lubbock, Texas, U.S.A. Pp. 87–116.
Yatskievych, G. 1999. Steyermark’s Flora of Missouri, 2nd ed., vol. 1. Missouri Department of Conservation and Missouri Botanical Garden, Jefferson City and St. Louis, U.S.A.
Yatskievych, G. 2006. Steyermark’s Flora of Missouri, 2nd ed., vol. 2. Missouri Botanical Garden Press, St. Louis, U.S.A.
Yatskievych, G. 2013. Steyermark’s Flora of Missouri, 2nd ed., vol. 3. Missouri Botanical Garden Press, St. Louis, U.S.A.
Zollner D, M.H. MacRoberts, B.R. MacRoberts, & D. Ladd. 2005. Endemic vascular plants of the Interior Highlands, U.S.A. Sida 21:1781–1791.