SIMPPLLE is a spatially-interactive, dynamic landscape modeling system for projecting temporal changes in the spatial distribution of vegetation in response to insects, disease, wildland fire, and other natural and management-caused disturbances. SIMPPLLE is designed to provide a balance between incorporating enough complexity and interactions in modeling ecosystem processes to provide an acceptable level of realism while making simplifications in the choices on required data input requirements, required computer platforms, and computing time to be a management tool useful in collaborative planning processes.