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We completed a soils and vegetation attribute study, in relation to Sonoran Desert Tortoise (SDT) (Gopherus morafkai) habitat, from December 5, 2009 to January 19, 2010 and again from March 29 to April 1, 2015 in Mojave County, Arizona on behalf of the Mojave Livestock Association. The survey covered approximately 956 square miles or 611,840 acres located from 5 to 80 plus miles south of Kingman, Arizona. The objectives of this study were to compare site specific landform, soils and vegetative characteristics to SDT density and distribution and attempt to identify detailed and quantifiable soils and landform characteristics that may be used to predict the distribution and densities of resident SDT, overlapping inhabitant Mojave Desert Tortoise (MDT)1 and any hybrids produced from the union of the SDT and MDT2 . An assessment of livestock use and potential competition for forage or habitat were considered. Similar efforts were completed in 19923 in Piute Valley, Clark County, Nevada for the MDT and in 19974 for 10 MDT study plots and surrounding areas located in Nye, Clark and Lincoln Counties in Nevada showing clear and definable relationships between soils, geomorphic surfaces (geomorphology), vegetation, and the distribution and densities of burrowing animals such as the MDT. The resultant soils classification criteria were evaluated by the National Resources Conservation Service (NRCS) who developed soils criteria and a soils report called WLF-Desert Tortoise. The information collected and analyzed from the Piute Valley study in the 1997 effort as revised in 20104 were compared with four existing SDT study plots that had previously been established on federal land within this study area in Mojave County, Arizona by the Bureau of Land Management (BLM) and the Arizona Game and Fish Department (AGFD). The agency study plots are named East Bajada, Buck Mountain, Hualapai Foothills and Arrastra Mountain.