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Fire Ecology Pete Fulé Northern Arizona University. Overview. Fire regimes Fire history methods Fire scars Comparison to records Fire and climate Effects of forest restoration on fire behavior Future fires: drought & beetles. Fire Regimes. Frequency
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Fire Ecology Pete Fulé Northern Arizona University
Overview • Fire regimes • Fire history methods • Fire scars • Comparison to records • Fire and climate • Effects of forest restoration on • fire behavior • Future fires: drought & beetles
Fire Regimes Frequency High frequency Low frequency IntensityHigh intensity High intensity (e.g., FL Everglades) (e.g., boreal, subalpine, lodgepole) High frequency Low frequency Low intensity Low intensity (e.g., ponderosa pine) (some deserts?)
Fire History Methods • Fire scars — common technique in surface-fire ecosystems. • Advantages: exact dates (even seasons of fires), locations of scarred trees. • Disadvantages: can’t map fire perimeter, absence of scars ≠ absence of fire. • Stand age — common technique in stand-replacing ecosystems. • Advantages: map perimeter/area of fire. • Disadvantages: imprecise fire date, newer fires obliterate evidence of older ones.
How good are fire scar methods? Critiqued by Baker & Ehle (2001, Can. J. Forest Research 31:1205-1226)
Comparison to Fire Records • Across western North America, we usually find sites with good records but no fires (USA), or many fires but limited records (Mexico).
Comparison to Fire Records • Across western North America, we usually find sites with good records but no fires (USA), or many fires but limited records (Mexico). • Grand Canyon has both: earliest recorded fire is the 1924 “Powell” fire.
Comparison to Fire Records • Across western North America, we usually find sites with good records but no fires (USA), or many fires but limited records (Mexico). • Grand Canyon has both: earliest recorded fire is the 1924 “Powell” fire. • Independent fire scar analysis found each of the 13 recorded fires > 20 acres since 1924 on the Powell, Rainbow, & Fire Pt. study sites (total of 1700 acres). Fulé, P.Z., T.A. Heinlein, W.W. Covington, and M.M. Moore. 2003. Assessing fire regimes on Grand Canyon landscapes with fire scar and fire record data. International Journal of Wildland Fire 12(2):129-145.
Emerald Prescribed Natural Fire August 10-24, 1993 Final size: 138 ha Stars indicate six samples that recorded the fire Six additional samples did not record the fire
Mixed Conifer Mid elevation site (2500 m): Swamp Ridge Northwest III Fire frequency: 6-9 years Last fire 1879 Forest: mixed conifer, formerly ponderosa pine Swamp Ridge, Grand Canyon N.P.
High elevation sites (2550-2800 m): Little Park Fire frequency: complex patterns, MFI25%= 31 yr MFIPoint= 32 yr Wt avg of fire-initiated stands = 22 yrs Last fire 1879 Forest: aspen, mixed conifer, spruce-fir
Forest Simulation and Fire Behavior Modeling Dendro Current Forest Structure (circa 2000) 1880 Forest Structure Site data FVS Tested procedures Add regen Simulate 1880-2040 • Intersecting evidence: • Lang & Stewart survey (1910) • Historical photos & data • Rasmussen (1941) Compared to measured data in 2000, +/- 20% Smoke Fire Plan Crown Biomass Forest Plan Biomass equations Wildlife Compared to observed fire behavior (NWIII fire & Outlet fire) Crowning Index Nexus Landscape Maps 1880-2040 Fire weather
Crown biomass changes in Grand Canyon forests, 1880-2040 Percent Mesic Species 1880: 30% @ 2500 m 65% @ 2650 m 86% @ 2700 m 2040: 60% @ 2500 m 86% @ 2650 m 96% @ 2700 m Fulé, P.Z., J.E. Crouse, A.E. Cocke, M.M. Moore, and W.W. Covington. 2003. Changes in canopy fuels and potential fire behavior 1880-2040: Grand Canyon, Arizona. Final Report to the Joint Fire Science Program, CA-1200-99-009-NAU 04 (Part 2).
Kaibab Plateau, Arizona Kaibab National Forest 2 5 6 1 7 3 4 Grand Canyon National Park • * Mean Fire Interval (10%-scarred < 2,500 m) • Fulé, P.Z., T.A. Heinlein, W.W. Covington, and M.M. Moore. 2003. Assessing fire regimes on Grand Canyon landscapes with fire scar and fire record data. International Journal of Wildland Fire 12(2). • Fulé, P.Z., J.E. Crouse, T.A. Heinlein, M.M. Moore, W.W. Covington, and G. Verkamp. 2003. Mixed-Severity Fire Regime in a High-Elevation Forest: Grand Canyon, Arizona. Landscape Ecology 18:465-486.
Fire and Climate • Climate is the major factor influencing distribution of ecosystems and occurrence of “fire weather”. • Southwest has frequent fires because climate is dry, hot, and windy nearly every summer. • Climate causes synchrony in burning across landscapes, mountain ranges, states. • Drought affects likelihood of fire. • El Niño/Southern Oscillation affects likelihood of fire.
Synchrony of Major Fire Years in the Southwest Swetnam, T.W., and C.H. Baisan. 2003. Tree-ring reconstructions of fire and climate history in the Sierra Nevada and southwestern United States. In: T.T. Veblen, W.L. Baker, G. Montenegro, and T.W. Swetnam (Editors), Fire and Climatic Change in Temperate Ecosystems of the Western Americas, Springer, New York, pp. 158-195.
Fire-ENSO Relationship Across the Southwest Swetnam, T.W., and C.H. Baisan. 2003. Tree-ring reconstructions of fire and climate history in the Sierra Nevada and southwestern United States. In: T.T. Veblen, W.L. Baker, G. Montenegro, and T.W. Swetnam (Editors), Fire and Climatic Change in Temperate Ecosystems of the Western Americas, Springer, New York, pp. 158-195.
Horseshoe Fire (1996) 8,650 acres Wallace Fire (1979) 327 acres Curley Fire (1980) 2,708 acres Slate Fire (1996) 379 acres Kelly Fire (1971) 2,732 acres Wild Bill Fire (1973) 7,814 acres Kendrick Fire (1980) 185 acres Kelly Fire (1954) 4,582 acres Kendrick Fire (1956) 292 acres ( ( ( / / / Hostetter Fire (1950) 1,077 acres (1968) 225 acres Burnt Fire (1973) 7,316 acres Pumpkin Fire (2000) 15,779 acres Hochderffer Fire (1996) 16,400 acres Bear Jaw Fire (1995) 780 acres Ft. Valley Fire (1948) 2,068 acres Trick Fire (1993) 344 acres White Horse Fire (1967) 865 acres Leroux Fire (2001) 1,113 acres Radio Fire (1977) 4,600 acres Power Fire (2000) 1,527 acres Pipe Fire (2000) 664 acres Side Fire (1996) 320 acres Belle Fire (1951) 1,128 acres A-1 Fire (1950) 1,002 acres . . . , , , - - - Joe Crouse, Andy Meador, Coconino NF data
Arizona 2002 Scar of the Rodeo-Chediski fire 468,638 acres NASA Visible Earth Credit:Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC Satellite:Terra Sensor:MODIS Data Start Date:06-30-2002
Does forest structure make a difference? This is the Trick Fire, 1993, burning near the San Francisco Peaks, AZ
Effects of forest restoration on fire behavior:Grand Canyon, Arizona
Restoration Techniques • Overstorytrees: thinning, species composition, spatial pattern, old-growth. • Understoryherbs and shrubs: natural regeneration, seeding, planting. • Fuels:accumulated fuels, canopy fuels, dead biomass as nutrient sources and habitat. • Fire:re-introducing fire, unique initial burn conditions, smoke. • Monitoring and adapting:evaluating results and making changes. Covington, W.W., P.Z. Fulé, M.M. Moore, S.C. Hart, T.E. Kolb, J.N. Mast, S.S. Sackett, and M.R. Wagner. 1997. Restoration of ecosystem health in southwestern ponderosa pine forests. Journal of Forestry 95(4):23-29.
Project Progress • Goal is to reduce uncharacteristically severe wildfire hazard, restore forest structure and dynamics. • Three experimental blocks measured 1997 (in the snow!) • Grand Canyon NP: draft EA 1998, protests of “logging in canyon,” no action taken. • New environmental process completed in 2002 with 5” diameter cap. Thinning completed by Northern Arizona Conservation Corps.
Northern Arizona Conservation Corps members thinning and piling slash with hand tools on Grand Canyon’s North Rim, October, 2002
Experimental Design • Kaibab National Forest: EA part of “Scott,” thinned 1999, burned fall 1999, remeasured 2000. • Control: continued fire exclusion. • Three restoration alternatives. • Full restoration: thinning (1.5/3 Rx), fuel treatment, rx fire. • Minimal thinning: thinning around old-growth trees, fuels, rx fire. • Burn-only: no fuel treatment, rx fire -- represents current management practice.
Burned October 1999 Full Restoration Minimal Thinning Fulé, P.Z., W.W. Covington, H.B. Smith, J.D. Springer, T.A. Heinlein, K.D. Huisinga, and M.M. Moore. 2002. Testing ecological restoration alternatives: Grand Canyon, Arizona. Forest Ecology and Management 170:19-41. Burn Only
Forest structure influences fire behavior Crown bulk density Fuel model 2 or 9 Canopy base height Fuel model 9 or 10
PRE-Treatment:torching at 21 mph, crowning at 33-40 mph. POST-Treatment (FULL):torching at 35 mph, crowning at 75 mph. Comparison to reference (1887) fire behavior:torching 42 mph, crowning 55-80 mph
Do model results hold up in real fires? Untreated stand, high density/high fuel Treated stand, low density/low fuel
Rodeo-Chediski fire 2002: White Mountain Apache lands No treatment, killed by fire Tree thinning and prescribed burning, survived fire
Effects of Treatments Treatments 1991-2001, forest above 6,560’, ≤ 45% slope 76% of untreated area burned moderate or high severity Only 4% (~1000 acres) of cut + burn had high severity
Future Fires • Increasing in size, intensity, and severity. • Increasing fire suppression costs and loss of life. • Firefighting priorities require focus on urban interface (lives & property) sacrificing wildlands. • Interaction with climate change: drought & beetles. Great Basin Incident Mgt Team (above)
Fuel hazards associated with bark beetle-caused tree mortality in the Southwest. forestfire.nau.edu/beetles.htm University of Arizona Arizona Public Service
“The most destructive fire … was fed by more than a million mature pine trees killed over the past year by a bark beetle infestation and drought. The fire front in the national forest was nearly 40 miles long … “ John M. Broder, NY Times, October 27, 2003 “Even before the winds came, the risk of fire in Southern California was considered extremely high because several years of drought had left trees vulnerable to the bark beetle and other pests and diseases. Hundreds of thousands of trees are estimated to have died, making them easy to burn.” Andrew Pollack, NY Times, October 27, 2003 Pine Bark Beetle Attack * Much of the “piñon/juniper type” forest includes some ponderosa pine. Figures for 2003 from FS Forest Health Protection program.