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NRCS and Robinett Rangeland Resources LLC used existing soil survey and published Ecological Site Descriptions to map ecological states on the University of Arizona Santa Rita Experimental Range (SRER, 5500 acres) and the USDA ARS Walnut Gulch Experimental Watershed (7000 acres) in 2016-17. We developed protocols a priori for validating ecological sites and states as a basis for developing maps. Classification criteria for shrubs and exotic grass species were derived from long-term vegetation monitoring on the SRER and expert judgement. Other indicators for classification criteria were developed in the field and documented. From these protocols, we produced high resolution maps, revised state-and-transition models (STMs) with field keys. In addition, we identified research questions and made recommendations for additional monitoring to help NRCS and other land management agencies refine and develop STMs. In this presentation, we will illustrate maps of ecological states on Limy Slopes 12-16 inch pz ecological site (with suggested revisions). We used the best available information from the published literature and expert consensus to define states, disturbance regimes, transitions and threshold values. Topographic and climatic gradients as well as a recent history of land treatments (brush management) and plant invasions (exotic grass species) on the Limy Slopes ES offer abundant research opportunities for students and researchers at UA and ARS.