Models of Vegetative Change for Landscape Planning: A Comparison of FETM, LANDSUM, SIMPPLLE, and VDDT

________________________________________ Landscape assessment and planning often depend on the ability to predict change of vegetation. This report compares four modeling systems (FETM, LANDSUM, SIMPPLLE, and VDDT) that can be used to understand changes resulting from succession, natural disturbance, and management activities. The four models may be useful for regional or local assessments in National Forest planning rules. Although these models are limited in their ability to support site-specific decisionmaking, they can prove helpful in understanding and comparing strongly differentiated alternatives. They can also be used to make sure that interdisciplinary planning teams share a common base of knowledge. Since all four models are still evolving, increased validation and documentation should develop over time. This report includes a comparison of the models in terms of purpose, data requirements, use, and outputs. It is intended to provide planners with a general introduction to the use of these models within a landscape assessment process.