AbstractsPhysics

Mastication is a fuel management technique that disrupts the vertical continuity of forest fuels by mechanical shredding of trees and understory vegetation into a highly-compacted surface fuelbed. The particle size distributions, bulk density and arrangements differ from natural and slash fuel types, thus resulting in fuelbeds with potentially different moisture dynamics and fire behaviour. We conducted three experiments, the first of which examined differences in in-stand micrometeorology and fuelbed moisture content between differing levels of stand thinning via mastication. In the second experiment, a fuel moisture model was created, validated with an independent dataset, and compared with pre-existing models that are incorporated in the Canadian Forest Fire Danger Rating System. In the third experiment, we compared the results of standard ignition tests performed on masticated fuelbeds in the laboratory and field to determine probability of sustained flaming, and compared our findings with pre-existing models of ignition for other forest fuels.