Incorporating landscape fuel treatment modeling into the Forest Vegetation Simulator

A simulation system was developed to explore how fuel treatments placed in random and optimal spatial patterns affect the growth and behavior of large fires when implemented at different rates over the course of five decades. The system consists of several command line programs linked together: (1) FVS with the Parallel Processor (PPE) and Fire and Fuels (FFE) extensions that pauses the simulation during each cycle and transfers data to and from other system components; (2) a component to create the spatial landscape file with fuel model logic to select fuel models not available in FFE; and (3) a command line version of FlamMap utilizing the Minimum Travel Time fire growth method and Treatment Optimization Model to identify treatments, simulate wildfires, and evaluate the performance of the fuel treatments. Simulations were performed for three study areas: Sanders County in western Montana, the Stanislaus National Forest in California, and the Blue Mountains in eastern Oregon utilizing the Inland Empire, Western Sierra, and Blue Mountain FVS variants. Several limitations of FVS were identified during the project. Understory vegetation important for fuel modeling is not simulated in FVS, and the cap of 10,000 stands in PPE limited the size of the analysis areas. This simulation system required a large time commitment for data development, multiprocessor computer hardware to perform the simulations, and a range of technical expertise that is more specialized than land management agencies are currently staffed to handle. The system was successful in meeting the project’s requirements. The research nature of this simulation system suggests it is probably not practical to run in most places for operational planning uses.