Prescribed fire in North American forests and woodlands: history, current practice, and challenges

Abstract

Whether ignited by lightning or by Native Americans, fire once shaped many North American ecosystems. Euro–American settlement and 20th‐century fire suppression practices drastically altered historic fire regimes, leading to excessive fuel accumulation and uncharacteristically severe wildfires in some areas and diminished flammability resulting from shifts to more fire‐sensitive forest species in others. Prescribed fire is a valuable tool for fuel management and ecosystem restoration, but the practice is fraught with controversy and uncertainty. Here, we summarize fire use in the forests and woodlands of North America and the current state of the practice, and explore challenges associated with the use of prescribed fire. Although new scientific knowledge has reduced barriers to prescribed burning, societal aversion to risk often trumps known, long‐term ecological benefits. Broader implementation of prescribed burning and strategic management of wildfires in fire‐dependent ecosystems will require improved integration of science, policy, and management, and greater societal acceptance through education and public involvement in land‐management issues.

Empirical Support for the Use of Prescribed Burning as a Fuel Treatment

“…PB often is the preferred fuel treatment due to economic and effectiveness considerations. By increasing frequency of application and reflecting distinct constraints and challenges, PB is practiced in a wide diversity of vegetation types in Europe [6], South Africa [7], North America [8] and Australia [3,9,10]. The success of a PB programme is conditional on the existence of a knowledgeable, experienced and flexible staff, institutional compliance with adaptive management and engagement with society [3].…”

Impacts of Mastication: Soil Seed Bank Responses to a Forest Thinning Treatment in Three Colorado (USA) Conifer Forest Types

“…Increasing fire hazards and fuel densities coupled with human encroachment into the wildland urban interface have prompted managers to implement fuel reduction treatments to reduce potential crown fire hazard and threat to property [3,5,[7][8][9][10]. One such fuels reduction treatment is mastication or the chipping or shredding of unwanted small diameter trees and shrubs, followed by broadcasting this material, commonly called mulch, across the treatment area [10,11].…”

Historical perspective on the influence of wildfire policy, law, and informal institutions on management and forest resilience in a multiownership, frequent-fire, coupled human and natural system in Oregon, USA

“…For instance, recent fire-prone forest restoration legislation (e.g., Healthy Forest Restoration Act) directs DNF, FWNF, and WSR land managers to treat forest fuels. In practice, however, community support influences flexibility to implement treatments (Ryan et al 2013) The importance of agency-community collaborative arrangements in forging broadly supported decisions on contentious topics has been demonstrated in forest ecosystems across the western United States (Wondelleck and Yaffee 1994). Our findings suggest that collaborative cultural norms are an integral element of such arrangements, possibly because of their capacity to shore up cross-ownership cooperation and trust, which are influential factors in wildfire decisions (Fischer and Charnley 2012).…”

“…Beginning in 1995, federal wildfire policy directed integration of "fire as a critical natural process" into management plans (USDI-USDA 1995), and by 2000, treatment of forest fuels (USDA-USDI 2000, Stephens and Ruth 2005). Equally important, Congress appropriated fuel treatment funding, which expanded manager flexibility to shift away from past suppression-based wildfire management (Ryan et al 2013). Over time, USFS managers shifted forest fuel practices from no treatment (stages I and II) to prescribed burn (stage III) and then to both mechanical and prescribed burn treatments (stages III and IV) and reduced harvest of large trees.…”