National Park Service U.S. Department of the Interior Natural Resource Stewardship and Science Vegetation Classification and Mapping at Thomas Stone National Historic Site, Maryland Natural Resource Technical Report NPS/NER/NRTR—2012/550 ON THE COVER Dry Mesic Forest at Thomas Stone National Historic Site. Photograph by: Chris Lea. Vegetation Classification and Mapping at Thomas Stone National Historic Site, Maryland Natural Resource Technical Report NPS/NER/NRTR—2012/550 Chris Lea1, Lesley A. Sneddon2, and Elizabeth Eastman3 1 National Park Service Natural Resource Information Division Vegetation Mapping Program P.O. Box 25287 Denver, CO 80228-0287 2 NatureServe c/o University of Massachusetts at Boston Biology Department 100 Morrissey Blvd. Boston, MA 02125-3393 3 North Carolina State University Center for Earth Observation Campus Box 7106 Raleigh, NC 27695-7106 February 2012 U.S. Department of the Interior National Park Service Natural Resource Stewardship and Science Fort Collins, Colorado The National Park Service, Natural Resource Stewardship and Science office in Fort Collins, Colorado publishes a range of reports that address natural resource topics of interest and applicability to a broad audience in the National Park Service and others in natural resource management, including scientists, conservation and environmental constituencies, and the public. The Natural Resource Technical Report Series is used to disseminate results of scientific studies in the physical, biological, and social sciences for both the advancement of science and the achievement of the National Park Service mission. The series provides contributors with a forum for displaying comprehensive data that are often deleted from journals because of page limitations. All manuscripts in the series receive the appropriate level of peer review to ensure that the information is scientifically credible, technically accurate, appropriately written for the intended audience, and designed and published in a professional manner. This report received informal peer review by subject-matter experts who were not directly involved in the collection, analysis, or reporting of the data. Data in this report were collected and analyzed using methods based on established, peer-reviewed protocols and were analyzed and interpreted within the guidelines of the protocols. Views, statements, findings, conclusions, recommendations, and data in this report do not necessarily reflect views and policies of the National Park Service, U.S. Department of the Interior. Mention of trade names or commercial products does not constitute endorsement or recommendation for use by the U.S. Government. This report is available from the Natural Resource Publications Management website (http://www.nature.nps.gov/publications/nrpm/). Please cite this publication as: Lea, C., L.A. Sneddon, and E. Eastman. 2012. Vegetation classification and mapping at Thomas Stone National Historic Site, Maryland. Natural Resource Technical Report NPS/NER/NRTR—2012/550. National Park Service, Fort Collins, Colorado. NPS 477/112894, February 2012 ii Contents Page Figures............................................................................................................................................. v Tables............................................................................................................................................. ix Appendixes .................................................................................................................................... xi Acknowledgments........................................................................................................................ xiii Executive Summary ...................................................................................................................... xv Introduction..................................................................................................................................... 1 General Background ................................................................................................................. 1 Park-specific Information ......................................................................................................... 2 Project Area .................................................................................................................................... 5 Location and Regional Setting .................................................................................................. 5 Park Environmental Attributes and Site History ...................................................................... 5 Floristic setting.......................................................................................................................... 7 Materials and Methods.................................................................................................................... 9 Planning and Scoping ............................................................................................................... 9 Preliminary Data Collection and Review of Existing Information ......................................... 10 Aerial Photography Acquisition and Processing .................................................................... 10 Orthophoto Mosaic Metadata ................................................................................................. 10 Photointerpretation and Development of the Formation-level Map ....................................... 13 Field Data Collection and Classification ................................................................................ 14 Vegetation Map Preparation ................................................................................................... 21 Accuracy Assessment ............................................................................................................. 21 iii Results........................................................................................................................................... 31 Vegetation Classification - Observation Points ...................................................................... 31 Vegetation Classification - Plots ............................................................................................. 32 Association Descriptions ........................................................................................................ 34 Vegetation Map Production .................................................................................................... 97 Accuracy Assessment ........................................................................................................... 102 Project Deliverables.............................................................................................................. 102 Discussion................................................................................................................................... 105 Vegetation Classification and Characterization .................................................................... 105 Vegetation Map Production .................................................................................................. 107 Accuracy Assessment ........................................................................................................... 107 Recommendations for Future Projects.................................................................................. 108 Literature Cited ........................................................................................................................... 109 iv Figures Page Figure 1. Location of Thomas Stone National Historic Site, Charles County, Maryland. ........................................................................................................................................ 3 Figure 2. Soil series of Thomas Stone National Historic Site (adapted from Hall and Mathews 1974). ........................................................................................................................ 6 Figure 3. Photo centers of the Thomas Stone National Historic Site leaf-on (fall) 2002 orthophoto mosaic, with association map for reference. ..................................................... 11 Figure 4. Photo centers of the Thomas Stone National Historic Site leaf-off (spring) 2002 orthophoto mosaic, with association map for reference. ........................................ 12 Figure 5. Vegetation observation (rapid assessment) points at Thomas Stone National Historic Site, May 2001. ................................................................................................ 16 Figure 6. Vegetation plots sampled at Thomas Stone National Historic Site. ............................. 18 Figure 7. Ground control points (n=23) used to calculate horizontal positional accuracy of the Thomas Stone National Historic Site leaf-off (spring) orthophoto mosaic. .......................................................................................................................................... 23 Figure 8. Ground control points (n=22) used to calculate horizontal positional accuracy of the Thomas Stone National Historic Site leaf-on (fall) orthophoto mosaic. .......................................................................................................................................... 24 Figure 9. Locations of sampling points in the northern section of Thomas Stone National Historic Site for the 2004 thematic accuracy assessment.