Fire in the landscape

Wildland fire is an episodic process that greatly influences the composition, structure, and developmental sequence of forests (McKenzie et al. 2011). Most news reports of wildland fire involves blazes fueled by slash, standing dead stems, and snags that reach into tree crowns and burn deeply into the forest floor, causing extensive tree mortality and the eventual replacement of the standing cohort of trees. Fires as part of a silvicultural prescription or that occur at the edges of wildfires are usually less devastating surface fires fueled by surface litter, herbaceous vegetation, and downed woody material. These fires tend to scorch the outer bark for some distance up the stem but generally do not extensively involve the crown or cause severe mortality of roots. Tree species vary in survival strategies under different fire regimes. Some species allocate resources to reduce injury by insulating stems from excessive heating. Other species rely on sprouting from the base of killed stems or from residual root systems. Still other species store or bank seeds in the forest floor that are ready to germinate after the fire passes. Most western “fire-adapted ” species rely on constitutive protection provided by thick bark as wells as by induced defenses to survive fire