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 digital aerial photos for Tonto NM were evaluated in ArcGIS (ESRI) to define and delimit distinct vegetation structural characteristics at what will hereafter be termed the “formation” level. Formations were defined by a combination of structural properties, including height, texture, color, and the relative percent cover of tree, shrub, and herbaceous vegetation. For Tonto NM, polygons (a closed line encompassing an area) were hand-digitized in ArcMap 9.0 (ESRI) around each visibly distinct formation across the entire park area, including a ~100-m buffer at the park boundary. Polygon lines were drawn such that homogeneity of visible characteristics was maximized within each polygon while minimizing the amount and size of structurally different inclusions of less than 0.5 hectares (1.24 ac) in size (Figure 2-2). Other spatial data were used to assist in this process, including digital elevation models (DEM) and contour lines. A minimum mapping unit of 0.5 hectares was observed, as set forth in the NVC standards. Distinct areas smaller than 0.5 hectares had to be included in an adjacent or enveloping polygon. All polygons were drawn such that adjacent polygon boundaries were shared, (i.e., there were no gaps between polygons) and complete coverage of the study area was achieved. The classification work led to the identification of 23 different vegetation types at the association level, attributed to 82 polygons.