The files linked to this reference are the geospatial data created as part of the completion of the baseline vegetation inventory project for the NPS park unit. Current format is ArcGIS file geodatabase but older formats may exist as shapefiles. The draft formation-level map was produced through limited field reconnaissance and visual interpretation of the pan-sharpened imagery and heads-up digitizing in ArcGIS to delineate polygons based on vegetation physiognomy. Spatial accuracy was assessed against 2006 digital orthophoto quarter quadrangle imagery, using 20 test points for each of the park’s three units. The maximum absolute error measured was less than 2 m ground distance, and maximum root mean square error was 1.03 m, well within the limits of the National Map Accuracy Standards.

The files linked to this reference are the geospatial data created as part of the completion of the baseline vegetation inventory project for the NPS park unit. Current format is ArcGIS file geodatabase but older formats may exist as shapefiles. A final vegetation map for TIMU was created to represent the vegetation occurring within the park during 2012. This product represents the final of four steps necessary to produce an accurate vegetation map based upon aerial photographs. This includes the determination of the community element global (CEGL) codes (2008) and acquisition of aerial imagery (2012), using the aerial imagery, with 162 ground truthing points (2014, 2015), to create a draft vegetation map, performing an accuracy assessment (2016), and then using all the available information to create a final vegetation map (2018).

The files linked to this reference are the geospatial data created as part of the completion of the baseline vegetation inventory project for the NPS park unit. Current format is ArcGIS file geodatabase but older formats may exist as shapefiles. A final vegetation map for TIMU was created to represent the vegetation occurring within the park during 2012. This product represents the final of four steps necessary to produce an accurate vegetation map based upon aerial photographs. This includes the determination of the community element global (CEGL) codes (2008) and acquisition of aerial imagery (2012), using the aerial imagery, with 162 ground truthing points (2014, 2015), to create a draft vegetation map, performing an accuracy assessment (2016), and then using all the available information to create a final vegetation map (2018).

The files linked to this reference are the geospatial data created as part of the completion of the baseline vegetation inventory project for the NPS park unit. Current format is ArcGIS file geodatabase but older formats may exist as shapefiles. Using field sample site information, the Alliance/Association classes were extrapolated to polygons sharing like aspects in the same regional area. A preliminary vegetation map was created and then reviewed by TNC field biologists for accuracy. If necessary, revisions to the delineations or the computer model were made and another map was produced for review. This process was repeated until the TNC biologists approved of all classification assignments.

The files linked to this reference are the geospatial data created as part of the completion of the baseline vegetation inventory project for the NPS park unit. Current format is ArcGIS file geodatabase but older formats may exist as shapefiles. Following the vegetation plot data analysis, the preliminary vegetation map was edited and refined to produce a revised preliminary vegetation map prior to thematic accuracy assessment (AA). Using ArcMap 9.2 (ESRI 1999-2006), polygon boundaries were revised on-screen using the newly acquired aerial orthophotography (digital photomosaic) based on the classification plot data, field observations, classification analyses, aerial photography signatures, and topographic maps. Each polygon was assigned the USNVC Community Element Global (CEGL) code of a preliminary vegetation association based on the information sources listed above. Second, third, and fourth CEGL code choices were entered in cases of uncertainty, or for polygons representing mosaics of two or more vegetation types.

The files linked to this reference are the geospatial data created as part of the completion of the baseline vegetation inventory project for the NPS park unit. Current format is ArcGIS file geodatabase but older formats may exist as shapefiles. Following the vegetation plot data analysis, the preliminary vegetation map was edited and refined to produce a revised preliminary vegetation map prior to thematic accuracy assessment (AA). Using ArcMap 9.2 (ESRI 1999-2006), polygon boundaries were revised on-screen using the newly acquired aerial orthophotography (digital photomosaic) based on the classification plot data, field observations, classification analyses, aerial photography signatures, and topographic maps. Each polygon was assigned the USNVC Community Element Global (CEGL) code of a preliminary vegetation association based on the information sources listed above. Second, third, and fourth CEGL code choices were entered in cases of uncertainty, or for polygons representing mosaics of two or more vegetation types.

The files linked to this reference are the geospatial data created as part of the completion of the baseline vegetation inventory project for the NPS park unit. Current format is ArcGIS file geodatabase but older formats may exist as shapefiles. In order to accommodate the complex vegetation patterns often found in National Park units and generally maintain a minimum mapping unit of 0.5 ha, a three-tiered scheme was developed for attributing vegetation polygons. Where appropriate, secondary and tertiary vegetation classes are added to describe mixed-plant communities within the polygon. Secondary and tertiary classes were especially useful for describing ecotones, and for polygons with a patchwork of communities below the minimum mapping unit size. Final products included seamless park-wide GIS databases in ArcGIS geodatabase and ArcView shapefile formats of detailed overstory vegetation communities, along with vegetation statistics, hardcopy maps and orthophoto images plotted at large scale corresponding to the park area.

The files linked to this reference are the geospatial data created as part of the completion of the baseline vegetation inventory project for the NPS park unit. Current format is ArcGIS file geodatabase but older formats may exist as shapefiles. Spatial data from field observation points and quantitative plots were used to edit the formation-level maps of Colonial National Historical Park to better reflect vegetation classes. Using ArcView 3.3, polygon boundaries were revised onscreen over leaf-off photography. Units used to label polygons on the map (i.e. map classes) are equivalent to one or more vegetation classes from the regional vegetation classification, or to a land-use class from the Anderson (Anderson et al. 1976) Level II classification system. Each polygon on the Colonial National Historical Park map was assigned to one of forty map classes based on plot data, field observations, aerial photography signatures, and topographic maps. The mapping boundary was based on park boundary data obtained Colonial National Historical Park in May 2003. The mapping boundary includes lands under a scenic easement at Swanns Point and it excludes the Cheatham Annex, an area that returned to US Navy ownership in February 2004. The vegetation map was clipped at the park boundary because areas outside the park were not surveyed or included in the accuracy assessment.

The files linked to this reference are the geospatial data created as part of the completion of the baseline vegetation inventory project for the NPS park unit. Current format is ArcGIS file geodatabase but older formats may exist as shapefiles. The map was designed to facilitate ecologically- based natural resources management at a 1:24,000 scale with 0.5-ha minimum map unit size. Based on a provisional assessment, overall accuracy was 82.5% for Level 1 and 66.8% for Level 2. Level 1 units will likely be sufficient and most appropriate for many natural resource planning and evaluations, while Level 2 units provide added fine-scale information within major ecological groups. To support the map as a management tool, we provide an annotated map legend along with descriptions of each plant association, a corresponding diagnostic key, field forms, and a plant species list. The map was delivered in both printed form and as digital Geographic Information System (GIS) map files. The GIS format allows flexibility to update the map as new information becomes available, or as major vegetation changes, such as fire, disease or other impacts, occur in the park.

The files linked to this reference are the geospatial data created as part of the completion of the baseline vegetation inventory project for the NPS park unit. Current format is ArcGIS file geodatabase but older formats may exist as shapefiles. Forty-two polygons were mapped within the project boundary: 27 at the main unit and 15 at the Adamsville proposed expansion area. In total, 15 distinct types were identified across the study area. Seven of these types are Anderson Land Use Classes or variations thereof; the others are natural vegetation classes following the NVCS. Map classes were described at the alliance or association level; where known, alliance descriptions also include recognized associations. Due to the small area involved in this project, and to its relatively simple floristic attributes, there is a one-to-one correspondence between the map classes presented here and the community types described. A total of 35 species were recorded during the sampling efforts. Alliances and associations marked with (P) are proposed, not yet accepted into the NVC. In addition, summarized local descriptions, with example satellite image/signatures and representative photos for each alliance or association, follow this section.