Background/Question/Methods Vegetation classification is used to help those interested in natural resources to organize and describe past, current, and future conditions of the ecosystems they manage, analyze, or research. The US National Vegetation Classification (NVC) was developed to classify and describe existing vegetation using a consistent approach that is suited to many business needs. The NVC can be effective in attributing and describing plant communities within an analytical frame that includes dynamics and the potential for varying expressions in vegetation over time. Here, the NVC is used to demonstrate the value of classification in delineating and describing different ecosystem phases and the effects of successional development, of management and land use, and of disturbance for purposes of state-and-transition model projections. The NVC can also be applied with climate-change forecasts of 21st-Century vegetation patterns.
Results/Conclusions A case example from montane forests of the southwestern US was used to demonstrate use of the NVC in describing and modeling ecosystem dynamics. An Ecological Site Description (ESD) was developed for the Ponderosa Pine-Evergreen Oak type, a warm-temperate ecosystem occurring below the Mogollon Rim in central and southern Arizona and New Mexico, equivalent to LANDFIRE’s Madrean Lower Montane Pine-Oak Forest and Woodland Biophysical Setting. Several NVC classes can be used to delineate and describe successional phases and disturbance transitions. There is sufficient detail in the NVC even at the level of Group, a middle level of the NVC hierarchy, to differentiate states and phases of a state-and-transition model for the ESD. Finally, impacts of 21st-Century climate trends are hypothesized using likely NVC Group outcomes. This case example shows a real-world application of the NVC for organizing and describing current and potential ecosystem conditions and related dynamics.