Increasing resiliency in frequent fire forests: Lessons from the Sierra Nevada and western Australia

Abstract

This paper will primarily focus on the management and restoration of forests adapted to frequent, low-moderate intensity fire regimes. These are the forest types that are most at risk from large, high-severity wildfires and in many regions their fire regimes are changing. Fire as a landscape process can exhibit self-limiting characteristics in some forests which can assist managers in mitigating large, severe wildfires. In mixed conifer forests in Yosemite National Park, when the amount of time between successive adjacent fires is under nine years, the probability of the latter fire burning into the previous fire area is low. Analysis of fire severity data by 10-year periods (from 1975-2005) revealed stability in the proportion of area burned over the last three decades; this contrasts with research demonstrating increasing high-severity burning in many Sierra Nevada forests. There is also evidence that intact fire regimes can constrain fire size. One of the world’s best examples of a prescribed fire program designed to reduce unwanted fire effects can be found near Perth, Australia. Approximately 8,500 prescribed burns have been conducted burning a total area of 15 million ha since 1950. Over this time an inverse relationship between the area burned by prescribed fire and wildfire has been established. However, the annual area of prescribed burning in this region is trending downwards since the 1980s while the annual area burned by wildfires is trending upwards. In contrast to crown-fire adapted ecosystems, areas that are adapted to frequent, low-moderate intensity fire regimes can be managed today to reduce their susceptibility to high severity fires and increase ecosystem resiliency. The current pace and scale of fuel treatments and managed wildfire are inadequate to increase ecosystem resiliency in forests in the western United States. Continued funding reductions for fuel reduction treatments is one of the most serious issues facing federal resource managers in the western United States working to increase forest resiliency.

Parent Publication

• Forest conservation and management in the Anthropocene: Conference proceedings

Citation

Stephens, Scott L. 2014. Increasing resiliency in frequent fire forests: Lessons from the Sierra Nevada and western Australia. In: Sample, V. Alaric; Bixler, R. Patrick, eds. Forest conservation and management in the Anthropocene: Conference proceedings. Proceedings. RMRS-P-71. Fort Collins, CO: US Department of Agriculture, Forest Service. Rocky Mountain Research Station. p. 123-132.