Analyzes a range of fuel treatments for representative dry forest stands in the Western U.S. dominated by ponderosa pine, Douglas-fir, & pinyon pine. Six silvicultural options (no thinning; thinning from below to 50 trees per acre [tpa], 100 tpa, 200 tpa, & 300 tpa; & prescribed fire) are considered in combination with the surface fuel treatments (no treatment, pile & burn, & prescribed fire), resulting in a range of alternative treatments for each representative stand. Fuel treatment scenarios presented here can be used by resource managers to examine alternatives for Nat. Environ. Policy Act documents & other applications that require scientifically based info. to quantify the effects of modifying forest structure & surface fuels. Illustrations.

The Fire and Fuels Extension of the Forest Vegetation Simulator (FFE-FVS) was used to calulate the immediate effects of treatments on surface fuels, fire hazard, potential fire behavior, and forest structure for respresentative dry forest stands in the Western United States. Treatments considered included pile and burn and prescribed fire.

Global warming is expected to change fire regimes, likely increasing the severity and extent of wildfires in many ecosystems around the world. What will be the landscape-scale effects of these altered fire regimes? Within what theoretical contexts can we accurately assess these effects? We explore the possible effects of altered fire regimes on landscape patch dynamics, dominant species (tree, shrub, or herbaceous) and succession, sensitive and invasive plant and animal species and communities, and ecosystem function. Ultimately, we must consider the human dimension: what are the policy and management implications of increased fire disturbance, and what are the implications for human communities?

This synthesis provides an ecological foundation for management of the diverse ecosystems and fire regimes of North America, based on scientific principles of fire interactions with vegetation, fuels, and biophysical processes. Although a large amount of scientific data on fire exists, most of those data have been collected at small spatial and temporal scales. Thus, it is challenging to develop consistent science-based plans for large spatial and temporal scales where most fire management and planning occur. Understanding the regional geographic context of fire regimes is critical for developing appropriate and sustainable management strategies and policy. The degree to which human intervention has modified fire frequency, intensity, and severity varies greatly among different ecosystems, and must be considered when planning to alter fuel loads or implement restorative treatments. Detailed discussion of six ecosystems--ponderosa pine forest (western North America), chaparral (California), boreal forest (Alaska and Canada), Great Basin sagebrush (intermountain West), pine and pine-hardwood forests (Southern Appalachian Mountains), and longleaf pine (Southeastern United States)--illustrates the complexity of fire regimes and that fire management requires a clear regional focus that recognizes where conflicts might exist between fire hazard reduction and resource needs. In some systems, such as ponderosa pine, treatments are usually compatible with both fuel reduction and resource needs, whereas in others, such as chaparral, the potential exists for conflicts that need to be closely evaluated. Managing fire regimes in a changing climate and social environment requires a strong scientific basis for developing fire management and policy. --