Effects of fuel treatments on California mixed-conifer forests

Land managers implement forest fuel reduction treatments, including prescribed fire, mastication, and hand- and mechanical thinning, to modify wildfire behavior. Fuel treatments decrease tree density, increase mean canopy base height and remove surface fuels, and have been shown to reduce fire severity in yellow pine and mixed-conifer forests, even under relatively severe weather conditions. However, less is known about the impacts of fuel treatments on other facets of forest ecology. Synthesizing evidence from the scientific literature regarding their effects on forest structure, carbon, vegetation, soils, wildlife and forest pests, we found a developing consensus that fuel treatments, particularly those that include a prescribed fire component, may have neutral to positive effects on a number of ecological processes in frequent-fire coniferous forests and may increase forest resilience to future disturbance and stress.