Register      Login
International Journal of Wildland Fire International Journal of Wildland Fire Society
Journal of the International Association of Wildland Fire
RESEARCH ARTICLE

Structure and composition of forest floor fuels in long-unburned Jeffrey pine-white fir forests of the Lake Tahoe Basin, USA

Erin M. Banwell A B D and J. Morgan Varner A C
+ Author Affiliations
- Author Affiliations

A Wildland Fire Laboratory, Department of Forestry & Wildland Resources, Humboldt State University, 1 Harpst Street, Arcata, CA 95521, USA.

B Present Address: 3060 NE Monterey Drive, Roseburg, OR 97470, USA.

C Present Address: Department of Forestry, Forest & Wildlife Research Center, Mississippi State University, Box 9681, Mississippi State, MS 39762, USA.

D Corresponding author. Email: banwelle@gmail.com

International Journal of Wildland Fire 23(3) 363-372 https://doi.org/10.1071/WF13025
Submitted: 15 February 2013  Accepted: 12 November 2013   Published: 7 March 2014

Abstract

In spite of the mechanistic links between forest floor fuels and fire behaviour and effects, little information is available on their composition and structure. We collected fuels from well-developed forest floors in four long-unburned Jeffrey pine (Pinus jeffreyi)–white fir (Abies concolor) forests in the Lake Tahoe Basin in California and Nevada. We measured forest floor (litter, fermentation and humus, where present) load, depth, bulk density and mineral ash content at the base of each tree, near the crown drip line and beyond the crown in open gaps (n = 40 Jeffrey pine, 40 white fir). We found substantial variability in composition between the two conifers’ forest floor fuels and across species. Forest floor was mounded near tree stems, with the majority of the depth (and mass) composed of fermentation fuels. Humus was present across spatial locations, but was patchier with increasing distance from trees. Ash content varied between trees (fir > pine) and with depth (humus > fermentation > litter). Results highlight the high spatial variation in forest floor fuels and underscore the need for building a greater understanding of forest floor fuels in long-unburned sites.

Additional keywords: conifers, duff, fuel classification.


References

Apigian K, Dahlsten D, Stephens SL (2006) Fire and fire surrogate treatment effects on leaf litter arthropods in a western Sierra Nevada mixed-conifer forest. Forest Ecology and Management 221, 110–122.
Fire and fire surrogate treatment effects on leaf litter arthropods in a western Sierra Nevada mixed-conifer forest.Crossref | GoogleScholarGoogle Scholar |

Banwell EM, Varner JM, Knapp EE, Van Kirk RW (2013) Spatial, seasonal, and diel forest floor moisture dynamics in Jeffrey pine-white fir forests of the Lake Tahoe Basin, USA. Forest Ecology and Management 305, 11–20.
Spatial, seasonal, and diel forest floor moisture dynamics in Jeffrey pine-white fir forests of the Lake Tahoe Basin, USA.Crossref | GoogleScholarGoogle Scholar |

Brown JK (1974) Handbook for inventorying downed woody material. USDA Forest Service, Intermountain Forest and Range Experiment Station, General Technical Report INT-16. (Ogden, UT)

Busse MD, Hubbert KR, Fiddler GO, Shestak CJ, Powers RF (2005) Lethal temperatures during burning of masticated forest residues. International Journal of Wildland Fire 14, 267–276.
Lethal temperatures during burning of masticated forest residues.Crossref | GoogleScholarGoogle Scholar |

Cannon SH, Powers PS, Savage WZ (1998) Fire-related hyperconcentrated and debris flows on Storm King Mountain, Glenwood Springs, Colorado. Environmental Geology 35, 210–218.
Fire-related hyperconcentrated and debris flows on Storm King Mountain, Glenwood Springs, Colorado.Crossref | GoogleScholarGoogle Scholar |

Cobb GW (1998) ‘Introduction to Design and Analysis of Experiments’. (Key College Publishing, Springer-Verlag: New York)

Covington WW, Sackett SS (1984) The effect of a prescribed burn in southwestern ponderosa pine on organic matter and nutrients in woody debris and forest floor. Forest Science 30, 183–192.

de Magalhães RMQ, Schwilk DW (2012) Leaf traits and litter flammability: evidence for non-additive mixture effects in a temperate forest. Journal of Ecology 100, 1153–1163.
Leaf traits and litter flammability: evidence for non-additive mixture effects in a temperate forest.Crossref | GoogleScholarGoogle Scholar |

Fonda RW (2001) Burning characteristics of needles from eight pine species. Forest Science 47, 390–396.

Fonda RW, Varner JM (2004) Burning characteristics of cones from eight pine species. Northwest Science 78, 322–333.

Frandsen WH (1987) The influence of moisture and mineral soil on the combustion limits of smoldering forest duff. Canadian Journal of Forest Research 17, 1540–1544.
The influence of moisture and mineral soil on the combustion limits of smoldering forest duff.Crossref | GoogleScholarGoogle Scholar |

Frandsen WH (1991) Burning rate of smoldering peat. Northwest Science 65, 166–172.

Garlough EC, Keyes CR (2011) Influences of moisture content, mineral content and bulk density on smouldering combustion of ponderosa pine duff mounds. International Journal of Wildland Fire 20, 589–596.
Influences of moisture content, mineral content and bulk density on smouldering combustion of ponderosa pine duff mounds.Crossref | GoogleScholarGoogle Scholar |

Gilliam FS, Platt WJ (1999) Effects of long-term fire exclusion on tree species composition and stand structure in an old-growth Pinus palustris (longleaf pine) forest. Plant Ecology 140, 15–26.
Effects of long-term fire exclusion on tree species composition and stand structure in an old-growth Pinus palustris (longleaf pine) forest.Crossref | GoogleScholarGoogle Scholar |

Greenberg JA, Dobrowski SZ, Ramirez CM, Tuil JL, Ustin SL (2006) A bottom-up approach to vegetation mapping of the Lake Tahoe Basin using hyperspatial image analysis. Photogrammetric Engineering and Remote Sensing 72, 581–589.

Haase SM, Sackett SS (1998) Effects of prescribed fire in giant sequoia-mixed conifer stands in Sequoia and Kings Canyon National Parks. In ‘Proceedings of the 20th Tall Timbers Fire Ecology Conference’, 7–10 May 1996, Boise, ID. (Eds TL Pruden, LA Bernnan) pp. 236–243. (Tall Timbers Research Station: Tallahassee, FL)

Hiers JK, O’Brien JJ, Will RE, Mitchell RJ (2007) Forest floor depth mediates understory vigor in xeric Pinus palustris systems. Ecological Applications 17, 806–814.
Forest floor depth mediates understory vigor in xeric Pinus palustris systems.Crossref | GoogleScholarGoogle Scholar | 17494398PubMed |

Hill MG (2006) Geology of the Sierra Nevada. (University of California Press: Berkeley, CA).

Hille MG, den Ouden J (2005) Fuel load, humus consumption and humus moisture dynamics in Central European Scots pine stands. International Journal of Wildland Fire 14, 153–159.
Fuel load, humus consumption and humus moisture dynamics in Central European Scots pine stands.Crossref | GoogleScholarGoogle Scholar |

Hille MG, Stephens SL (2005) Mixed conifer forest duff consumption during prescribed fires: Tree crown impacts. Forest Science 51, 417–424.

Hood SM (2010) Mitigating old tree mortality in long-unburned, fire-dependent forests: a synthesis. USDA Forest Service, Rocky Mountain Research Station. General Technical Report RMRS-GTR-238. (Fort Collins, CO)

Horwitz W (1965) ‘Official Methods of Analysis of the Association of Official Agricultural Chemists’. (Association of Official Analytical Chemists: Washington, DC)

Jain T, Juillerat M, Sandquist J, Ford M, Sauer B, Mitchell R, McAvoy S, Hanley J, David J (2007) Vegetation and soil effects from prescribed, wild, and combined fire events along a ponderosa pine and grassland mosaic. USDA Forest Service, Rocky Mountain Research Station. Research Paper RMRS-RP-67CD. (Fort Collins, CO)

Keane R (2013) Describing wildland surface fuel loading for fire management: a review of approaches, methods and systems. International Journal of Wildland Fire 22, 51–62.
Describing wildland surface fuel loading for fire management: a review of approaches, methods and systems.Crossref | GoogleScholarGoogle Scholar |

Kilgore BM, Taylor D (1979) Fire history of a sequoia–mixed conifer forest. Ecology 60, 129–142.
Fire history of a sequoia–mixed conifer forest.Crossref | GoogleScholarGoogle Scholar |

Knapp EE, Keeley JE (2006) Heterogeneity in fire severity within early and late season prescribed burns in a mixed conifer forest. International Journal of Wildland Fire 15, 37–45.
Heterogeneity in fire severity within early and late season prescribed burns in a mixed conifer forest.Crossref | GoogleScholarGoogle Scholar |

Knapp EE, Keeley JE, Ballenger EA, Brennan TJ (2005) Fuel reduction and coarse woody debris dynamics with early season and late season prescribed fire in a Sierra Nevada mixed conifer forest. Forest Ecology and Management 208, 383–397.
Fuel reduction and coarse woody debris dynamics with early season and late season prescribed fire in a Sierra Nevada mixed conifer forest.Crossref | GoogleScholarGoogle Scholar |

Kreye JK, Varner JM, Dugaw CJ, Cao J, Szecsei J, Engber EA (2013) Pine cones facilitate ignition of forest floor duff. Canadian Journal of Forest Research 43, 512–516.
Pine cones facilitate ignition of forest floor duff.Crossref | GoogleScholarGoogle Scholar |

Loftis WR (2007) Soil survey of the Tahoe Basin Area, California and Nevada. USDA, Natural Resources Conservation Service. Available at http://soils.usda.gov/survey/printed_surveys/ [Verified 17 July 2013]

Miyanishi K (2001) Duff consumption. In ‘Forest Fires, Behavior and Ecological Effects’. (Eds EA Johnson, K Miyanishi) pp. 437–475. (Academic Press: San Diego, CA)

Morris SE, Moses TA (1987) Forest fire and the natural soil erosion regime in the Colorado Front Range. Annals of the Association of American Geographers 77, 245–254.
Forest fire and the natural soil erosion regime in the Colorado Front Range.Crossref | GoogleScholarGoogle Scholar |

Murphy JD, Johnson DW, Miller WW, Walker RF, Carroll EF, Blank RR (2006) Wildfire effects on soil nutrients and leaching in a Tahoe Basin watershed. Journal of Environmental Quality 35, 479–489.
Wildfire effects on soil nutrients and leaching in a Tahoe Basin watershed.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XisFKrtbo%3D&md5=6fecfaf149aa32bc7001e05fba5f6febCAS | 16455848PubMed |

O’Brien JJ, Hiers JK, Mitchell RJ, Varner JM, Mordecai K (2010) Acute physiological stress and mortality following fire in a long-unburned longleaf pine ecosystem. Fire Ecology 6, 1–12.
Acute physiological stress and mortality following fire in a long-unburned longleaf pine ecosystem.Crossref | GoogleScholarGoogle Scholar |

Philpot CW (1970) Influence of mineral content on the pyrolysis of plant materials. Forest Science 16, 461–471.

Pritchett WL (1979) ‘Properties and Management of Forest Soils.’ (Wiley: New York)

Reardon J, Hungerford R, Ryan K (2007) Factors affecting sustained smoldering in organic soils from pocosin and pond pine woodland wetlands. International Journal of Wildland Fire 16, 107–118.
Factors affecting sustained smoldering in organic soils from pocosin and pond pine woodland wetlands.Crossref | GoogleScholarGoogle Scholar |

Ryan KC, Frandsen WH (1991) Basal injury from smoldering fires in mature Pinus ponderosa Laws. International Journal of Wildland Fire 1, 107–118.
Basal injury from smoldering fires in mature Pinus ponderosa Laws.Crossref | GoogleScholarGoogle Scholar |

Skinner CN, Chang C (1996) Fire regimes, past and present. In ‘Sierra Nevada Ecosystem Project: Final Report to Congress, Vol. II: Assessments and Scientific Basis for Management Options’. pp. 1041–1069. Water Resources Center Report 37. (Centers for Water and Wildland Resources, University of California: Davis, CA)

Stephens SL (2001) Fire history in adjacent Jeffrey pine and upper montane forests in the eastern Sierra Nevada. International Journal of Wildland Fire 10, 161–176.
Fire history in adjacent Jeffrey pine and upper montane forests in the eastern Sierra Nevada.Crossref | GoogleScholarGoogle Scholar |

Stephens SL, Finney MA (2002) Prescribed fire mortality of Sierra Nevada mixed conifer tree species: effects of crown damage and forest floor combustion. Forest Ecology and Management 162, 261–271.
Prescribed fire mortality of Sierra Nevada mixed conifer tree species: effects of crown damage and forest floor combustion.Crossref | GoogleScholarGoogle Scholar |

Stephens SL, Finney MA, Shantz H (2004) Bulk density and fuel loads of ponderosa pine and white fir forest floors: impacts of leaf morphology. Northwest Science 78, 93–100.

Swezy DM, Agee JK (1991) Prescribed fire effects on fine root and tree mortality in old growth ponderosa pine. Canadian Journal of Forest Research 21, 626–634.
Prescribed fire effects on fine root and tree mortality in old growth ponderosa pine.Crossref | GoogleScholarGoogle Scholar |

Swift T, Perez-Losada J, Schladow SG, Reuter J, Jassby D, Goldman C (2006) Water clarity modeling in Lake Tahoe: linking suspended matter characteristics to Secchi depth. Aquatic Sciences 68, 1–15.
Water clarity modeling in Lake Tahoe: linking suspended matter characteristics to Secchi depth.Crossref | GoogleScholarGoogle Scholar |

Taylor AH (2004) Identifying forest reference conditions on cut-over lands, Lake Tahoe Basin, USA. Ecological Applications 14, 1903–1920.
Identifying forest reference conditions on cut-over lands, Lake Tahoe Basin, USA.Crossref | GoogleScholarGoogle Scholar |

Taylor AH, Beaty RM (2005) Climatic influences on fire regimes in the northern Sierra Nevada mountains, Lake Tahoe Basin, Nevada, USA. Journal of Biogeography 32, 425–438.
Climatic influences on fire regimes in the northern Sierra Nevada mountains, Lake Tahoe Basin, Nevada, USA.Crossref | GoogleScholarGoogle Scholar |

Taylor KL, Fonda RW (1990) Woody fuels structure and fire in subalpine forests, Olympic National Park, Washington. Canadian Journal of Forest Research 20, 193–199.
Woody fuels structure and fire in subalpine forests, Olympic National Park, Washington.Crossref | GoogleScholarGoogle Scholar |

van Wagtendonk JW, Fites-Kaufman J (2006) Sierra Nevada bioregion. In ‘Fire in California’s Ecosystems’. (Eds NG Sugihara, JW van Wagtendonk, KE Shaffer, J Fites-Kaufman, AE Thode) pp. 264–294. (University of California Press: Berkeley, CA)

van Wagtendonk JW, Moore PE (2010) Fuel deposition rates of montane and subalpine conifers in the central Sierra Nevada, California, USA. Forest Ecology and Management 259, 2122–2132.
Fuel deposition rates of montane and subalpine conifers in the central Sierra Nevada, California, USA.Crossref | GoogleScholarGoogle Scholar |

van Wagtendonk JW, Benedict JM, Sydoriak WS (1998) Fuel bed characteristics of Sierra Nevada conifers. Western Journal of Applied Forestry 13, 73–84.

Varner JM, Gordon DR, Putz FE, Hiers JK (2005) Restoring fire to long-unburned Pinus palustris ecosystems: novel fire effects and consequences for long-unburned ecosystems. Restoration Ecology 13, 536–544.
Restoring fire to long-unburned Pinus palustris ecosystems: novel fire effects and consequences for long-unburned ecosystems.Crossref | GoogleScholarGoogle Scholar |

Varner JM, Hiers JK, Ottmar RD, Gordon DR, Putz FE, Wade DD (2007) Overstory tree mortality resulting from reintroducing fire to long-unburned longleaf pine forests: the importance of duff moisture. Canadian Journal of Forest Research 37, 1349–1358.
Overstory tree mortality resulting from reintroducing fire to long-unburned longleaf pine forests: the importance of duff moisture.Crossref | GoogleScholarGoogle Scholar |

Varner JM, Putz FE, O’Brien JJ, Hiers JK, Mitchell RJ, Gordon DR (2009) Post-fire tree stress and growth following smoldering duff fires. Forest Ecology and Management 258, 2467–2474.
Post-fire tree stress and growth following smoldering duff fires.Crossref | GoogleScholarGoogle Scholar |