Chapter 13 - Conventional fire behavior modeling systems are inadequate for predicting fire behavior in bark beetle-impacted forests (Project INT-EM-F-11-03)
| Authors: | Sharon M. Hood, Robert E. Keane, Helen Y. Smith, Joel Egan, Lisa Holsinger |
| Year: | 2018 |
| Type: | General Technical Report |
| Station: | Southern Research Station |
| Source: | In: Potter, Kevin M.; Conkling, Barbara L., eds. 2018. Forest health monitoring: national status, trends, and analysis 2017. General Technical Report SRS-233. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. |
Abstract
Understanding the impacts of mountain pine beetle (MPB; Dendroctonus ponderosae Hopkins) on fire behavior is important from both an ecological and land management viewpoint. However, numerous uncertainties exist in the linkages of MPB-caused treemortality to changes in canopy and surface fuels (e.g., fuel loading, arrangement, and availability) and the effects on simulated and observed fire behavior in MPB-attacked forests. Current fuel inputs to fire behavior models may be poorly suited to predict fire behavior in these disturbed forests because of inappropriate assumptions, resolutions, and design. Spatial patterns of recent beetle mortality are difficult to realistically represent in fire models, and it is virtually impossible to determine model output accuracy in a planning scenario. The numerous stages of tree condition (green-infested, red, and gray phases) due to time since attack further complicate modeling. MPB-killed foliage is more flammable than green needles (Jolly and others 2012); however, it is unknown if this increase in flammability scales up to entire canopies to result in higher-intensity crown fires (Alexander and Cruz 2013).