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Ecological site description in forested environments is complex and often confounded by variations in climate and topography that drive forest productivity. The Sierra Nevada mountains of California, Major Resource Land Area (MLRA) 22A, offers a unique set of challenges due to the extreme elevation and latitudinal gradients. Both users and producers of ecological site descriptions (ESDs) may benefit fromESDs based on a finer-scale designation known as the Land Resource Unit (LRU). Hierarchically, the LRU is nested within the MLRA and specifies ranges for a specific climatic zone that can accommodate a suite of similar ESDs from a management perspective. During a pilot study, we employed an unsupervised classification of LRU zones using several coarse-scale climatic and topographic variables to determine the relevant climatic ranges for such zones. In order to assess the validity of the LRU classification, we will use ground truth data collected from the ongoing Sequoia-Kings Canyon (SEKI) National Park soil survey. During the summer months of 2012-2014, we visited nearly 500 points to collect detailed soils and vegetation data (including observed LRU zone). For our next step, we endeavor to determine the producer error rate for five of the LRU zones (those occurring within SEKI) and to identify other variables that may be useful in improving the classification accuracy. The park boundary is only a fraction of the extent of the entire MLRA and offers an ideal testing ground to develop LRU models for the entire Sierra Nevada.