The zip file contains a large tiff mosaic stitched together from a series of aerial photographs of the Calhoun CZO area taken in 1933, when the area was being acquired by the US Forest Service. USFS archaeologist Mike Harmon delivered the black-and-white photographs, known to him as the 'Sumter National Forest Purchase Aerials', to us in a box. The photographs include most of the Enoree District of the Sumter National Forest, including the entirety of the Calhoun CZO, not just the long-term plots and small watersheds. The photographs were scanned and georectified, then color-balanced and stitched together following 'seams' - high-contrast features such as rivers and roads ('seamlined'). In addition to the main tiff are four files that can be used to properly geolocate the composite image in ArcGIS.

The multilayer pdf file includes a smaller version of the seamlined 1933 aerial photography mosaic raster layer, as well as this aerial mosaic transparent over slope map (for a 3D-like 1933 image raster). Other layers include contours, roads, boundaries, sampling locations, 1.5 m DEM, 1.5m slope, 1m 2013 NAIP aerial imagery, and 2014 canopy height. The pdf file includes both 'interfluve order' and 'landshed order.' These two layers mean the same thing, but the landshed is the area unit around the interfluve that is used for statistics; this dataset has been QC'ed. The Interfluve Order network was used to delineate the landsheds and agrees with it >95% of the time, but has a few inaccuracies (it was automated by the computer) that were fixed manually. Use the network for viewing and considering the landscape at large, but for the specific interfluve order, check the color of the 'Landshed Order' dataset to verify its accuracy.

Date Range Comments: The exact date these photos were taken is unknown, but the year is thought to be 1933.The flight date is prior to the USFS land purchases for the Enoree District of the Sumter National Forest; the photos are thus known as the "pre-purchase photos").