W&M ScholarWorks Dissertations, Theses, and Masters Projects Theses, Dissertations, & Master Projects 2000 Plant Species of the Virginia Coastal Plain Flora that Are Disjunct from the Mountains: their Distribution, Abundance and Substrate Selectivity Leah E. McDonald College of William & Mary - Arts & Sciences Follow this and additional works at: https://scholarworks.wm.edu/etd Part of the Botany Commons Recommended Citation McDonald, Leah E., "Plant Species of the Virginia Coastal Plain Flora that Are Disjunct from the Mountains: their Distribution, Abundance and Substrate Selectivity" (2000). Dissertations, Theses, and Masters Projects. Paper 1539626249. https://dx.doi.org/doi:10.21220/s2-qs24-sy54 This Thesis is brought to you for free and open access by the Theses, Dissertations, & Master Projects at W&M ScholarWorks. It has been accepted for inclusion in Dissertations, Theses, and Masters Projects by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. Plant Species of the Virginia Coastal Plain Flora that are Disjunct from the Mountains: their Distribution, Abundance and Substrate Selectivity A Thesis Presented to The Faculty of the Department of Biology The College of William and Mary in Virginia In Partial Fulfillment Of the Requirements for the Degree of Master of Arts by Leah E. McDonald 2000 APPROVAL SHEET This thesis is submitted in partial fulfillment the requirements for the degree of Master of Arts A uthor Approved, October 2000 ^JX ^/[ItX^j { Stewart A. Ware Martha A. Case l ^ O n n Q /V- & ' A m z Donna M. E. Ware Dedicated to my grandfather, Felix Maiorana, and my mother, Kathleen McDonald TABLE OF CONTENTS Page ACKNOWLEDGMENTS................................................................................................... vi LIST OF TABLES................................................................................................................vii LIST OF FIGURES............................................................................................................ viii ABSTRACT........................................................................................................................... xi INTRODUCTION............................................................. 2 METHODS AND MATERIALS...................................................................................... 13 Determination of mountain disjunct species ....................................................13 Mapping of "less disjunct" species ...................................................... 17 Vegetation studies ......................................................................................... 29 Selection of study sites ..............................................................................29 Sampling of ground layer vegetation and collection of environmental data ................................................................................... 32 Sampling of woody vegetation ............................................................... 37 Ordination analysis .............................................................................. 38 Soil tolerance experiments ........................................................................38 RESULTS................................ 43 Maps of individual collection locations for the less disjunct species 43 Ground layer vegetation ....................................................................................... 63 Woody vegetation ................................................................................................. 103 Soil tolerance experiments .................................................................................. 116 DISCUSSION...................................................................................................................... 127 APPENDIX A- The number of specimens of less disjunct species examined and m ap p ed ................ 137 TABLE OF CONTENTS (continued) Page APPENDIX B- Maps of the study sites .........................................................................139 APPENDIX C- Seed sources for the species used in the soil tolerance experiments ............................................................. 147 APPENDIX D- Soil data for all study sites ...................................................................149 APPENDIX E- G round layer data ................................................................................. 153 LITERATURE CITED ....................... 248 v ACKNOWLEDGMENTS I wish to extend my sincerest gratitude to Dr. Stewart A. Ware, thesis advisor, for counsel and guidance throughout this study. I am truly thankful for his assistance in the field, advice concerning methodologies, help with analysis of the results and enthusiasm for this study. I would also like to thank members of my committee, Dr. Donna M. E. Ware and Dr. Martha A. Case for reviewing this manuscript and for advice throughout this endeavor. Dr. Donna M.E. Ware assisted greatly with field trips, selection of study sites and identification of herbaceous species. Dr. Martha A. Case provided invaluable advice on the methodology for the soil tolerance experiments and statistical analysis of those experiments. Others whose efforts I am grateful for are Dr. C. Rick Berquist for assistance with geology and Gary Fleming for his expert botanical advice. Special appreciation is extended to Tom Wieboldt, Dr. Alton Harvill and Dr. Ted Bradley, all curators of herbaria, for their help and hospitality during my stay at their respective herbaria. Dr. Ruth Douglas, Dr. Gwynn Ramsey and Dr. Doug Ogle graciously collected seeds for the soil tolerance experiments. Field assistance from Elizabeth Brewster, Eric Dunlavey, Holly Grubbs, Esther McDonald, and Jacques Oliver made data collection possible; and I greatly appreciate their help. I also wish to recognize Maiy Hyde Berg who assisted with the selection of the study site in Gloucester Co. Thanks goes to my family for their love and tireless encouragement from the beginning to the end of this project. My deepest gratitude goes to Jacques Oliver for his continuous love, support, perspective, and patience throughout this work. This study was made possible through the generous support of the Virginia Crouch Memorial Research Grant, the Barbara J. Harvill Memorial Grant and a Minor Research Grant from the College of William and Mary. vi LIST OF TABLES Table Page 1. Mountain disjunct species recorded in floristic studies in the Coastal Plain counties of Virginia. ......................................................................10 2. Species identified as mountain disjuncts by this study ...................................14 3. Coverage classes for the ground layer vegetation .............................................35 4. Mountain disjunct species used in the soil tolerance experiments .............. 39 5. Soil chemistry data for the two types of soil (calcareous and non-calcareous) used in the soil tolerance experiments .................................41 6. Herbaceous and woody seedling species identified in study plots of the calcareous and non-calcareous ravines ................................................. 67 7. The calcareous sites and ravines where disjunct species are located ...........71 8. Soil pH for the calcareous ravines and associated uplands ............................79 9. Soil pH for the non-calcareous ravines ................................................................ 81 10. Mountain disjunct species and soil pH ........................... 83 11. Plot numbers for the ground layer data ................. 86 12. Plot numbers for the tree and shrub data .......................................................... 107 13. The number of specimens of less disjunct species examined and and m ap p ed ...................................................................................... 138 14. Seed sources for the species used in the soil tolerance experiments 148 15. Soil data for all sites ............................ 150 vii LIST OF FIGURES Figure Page 1. The physiographic provinces of Virginia ............................................................4 2. The Coastal Plain of Virginia with number of mountain disjuncts reported from floristic studies. ..............................................................................8 3. Distribution maps of mountain disjunct from the Atlas of the Virginia Flora (Harvill et al.1992) ......................................................................................18 4. Map of the Virginia Coastal Plain showing the five counties with study sites........................ 31 5. Cross section of a typical ravine with 1 x 1 m plots set up in transects to sample the ground layer vegetation ............................................................. 33 6. Map of individual collection locations for Amianthium muscaetoxicum... 45 7. Map of individual collection locations for Comptonia peregrina..................46 8. Map of individual collection locations for Galax urceolata............................ 47 9. Map of individual collection locations for Anemone quinquefolia ................ 48 10. Map of individual collection locations for Dirca palustris............................. 49 11. Map of individual collection locations for Bidens cernua...............................50 12. Map of individual collection locations for Scutellaria ovata........................... 51 13. Map of individual collection locations for Taenidia integerrima....................52