Table 2.
Examples of wildfire management of unplanned ignitions and the influence of past wildfires in national parks and wilderness areas.
| Area | Management objective | Study findings | Biophysical setting | Reference |
|---|---|---|---|---|
| North Rim Grand Canyon National Park, AZ | Restoring fire; created strategic fuel reductions to allow for natural fire to return | Fires have thinning effect on small diameter trees along with fine fuel and coarse wood consumption | dry ponderosa pine forest and shrublands; cold dry mixed conifer forests | Fulé and Laughlin (2007), Stoddard et al. (2020) |
| Saguaro Wilderness, AZ | Sky islands; 30 yr of repeated wildland fires | Repeat fires have reduced small density trees but medium trees are still denser than historical stand structures probably supported | dry ponderosa pine forest and shrublands | Holden et al. (2007), Hunter et al. (2014) |
| Hualapai tribal lands, AZ | Compared fire scars with modern use of low‐intensity prescribed burning | Prescribed fires since the 1960s approximate the frequent surface fires of historical record but could incorporate greater variability in temporal schedules of burning | Dry ponderosa pine forests | Stan et al. (2014) |
| Gila/Aldo Leopold Wilderness, NM |
Restore fire as natural process Surface loads and continuity drive high fire frequency on productive sites |
Low severity fires beget low severity fires, and high severity fires tend to reburn at high severity in flammable shrub fields. Previous fires reduce size of subsequent fires for a short period of time | dry ponderosa pine forest and shrublands; dry mixed conifer forest; some cold forest |
Rollins et al. (2002), Holden et al. (2007, 2010), Hunter et al. (2014), Parks et al. (2014, 2015a , 2016, 2018), Holsinger et al. (2016) |
| Zion National Park, UT | Science‐based fire management plan including managed wildfires, prescribed burning, and hazardous fuel reduction | Repeat prescribed fires reduce probability of crown fire and increased grass and forb cover, but not tree density or shrub cover | dry ponderosa pine forest and shrublands | Brown et al. (2019) |
| Yosemite National Park (YNP), CA | Restore fire as natural process; began with fires within the park interior and gradually worked outward to allow for more fires throughout park | High severity burns favor flammable shrub fields, which perpetuate high severity reburns. Low severity burns perpetuate low severity burns | Boisramé et al. (2017), Collins et al. (2009), Coppoletta et al. (2016), Scholl and Taylor (2010), Thode et al. (2011), van Wagtendonk et al. (2012) | |
| Sequoia and Kings Canyon National Parks, Giant Sequoia National Monuments, CA | Restore fire as natural process | In red fir forests, repeated low‐ to moderate‐severity fire can restore structural heterogeneity | Meyer et al. (2015) | |
| Frank Church – River of No Return Wilderness, ID | Restore fire as natural process | Burn severity is lower within recent fire areas and increases with time since fire. Previous fires reduce size of subsequent fires | dry mixed conifer forests and cold forests | Teske et al. (2012), Parks et al. (2014, 2015a , 2016, 2018), Holsinger et al. (2016) |
| Bob Marshall Wilderness Area, MT | Restore fire as natural process | Previous fires reduce size of subsequent fires | cold mixed conifer forests, Rocky Mountains | Belote et al. (2015), Holsinger et al. (2016), Keane et al. (2006), Larson et al. (2013a ), Parks et al. (2015a , 2016, 2018), Teske et al. (2012) |
| Selway‐Bitterroot Wilderness Complex, ID and MT | Restore fire as natural process; moisture content of large fuels and tree crowns drive fire frequency (higher on drier sites) | Previous fires reduce size of subsequent fires | cold mixed conifer and subalpine forests | Rollins et al. (2002), Parks et al. (2015a ), 2016, 2018), Barnett et al. (2016a ), Holsinger et al. (2016), Morgan et al. (2017), Teske et al. (2012) |
| Banff, Kootenay and Yoho National Parks (NP), BC & Alberta, Canada | Guard fires to allow for more natural ignitions to burn within park; restoration of aspen and grasslands (bison habitat) | Multiple prescribed burns to reduce dense lodgepole pine (LPP) and allow aspen to regenerate | cold mixed conifer and subboreal forests, Rocky Mountains | White (1985), Park et al. (2019) |
| Wood Buffalo National Park, AB and NWT, Canada | Restore and maintain fire as natural process | Fire severity is influenced by pre‐fire stand structure and composition, topoedaphic context, and fire weather at time of burning. Burned areas less likely to burn again for 33 yr, though this decreases in drought years | vegetation is representative of the western Canadian boreal forest | Parks et al. (2018), Thompson et al. (2017), Whitman et al. (2019) |
State and province abbreviations are AZ, Arizona; NM, New Mexico; ID, Idaho; MT, Montana; BC, British Columbia; AB, Alberta; NWT, North West Territory.