The diversity of alluvial fan and pediment ages and the pristine Sonoran desert vegetation of the Table Top Mountains make this region ideally suited to study relationships between geomorphic surfaces, soil development, and vegetation distribution. The Table Top Mountains and flanking piedmonts, located about 30 km (20 mi) southwest of Casa Grande and about 50 km (30 miles) east-southeast of Gila Bend in south-central Arizona, lie mostly within the Table Top Wilderness Area, administered by the Bureau of Land Management (Fig. 1). The range is dominated by the mesa-like Table Top Mountain (1333 m, 4374 ft elevation) and is surrounded by smaller hills and extensive alluvial deposits of varying ages. This study describes the surficial geology, soils, and vegetation patterns on the piedmonts flanking the mountain mass.