Free Standard AU & NZ Shipping For All Book Orders Over $80!
Register      Login
International Journal of Wildland Fire International Journal of Wildland Fire Society
Journal of the International Association of Wildland Fire
RESEARCH ARTICLE

Seasonal variation in surface fuel moisture between unthinned and thinned mixed conifer forest, northern California, USA

Becky L. Estes A B C , Eric E. Knapp A , Carl N. Skinner A and Fabian C. C. Uzoh A
+ Author Affiliations
- Author Affiliations

A USDA Forest Service, Pacific Southwest Research Station, 3644 Avtech Parkway, Redding, CA 96002, USA.

B Present address: Eldorado National Forest, 100 Forni Road, Placerville, CA 95667, USA.

C Corresponding author. Email: bestes@fs.fed.us

International Journal of Wildland Fire 21(4) 428-435 https://doi.org/10.1071/WF11056
Submitted: 27 April 2011  Accepted: 13 October 2011   Published: 12 April 2012

Abstract

Reducing stand density is often used as a tool for mitigating the risk of high-intensity crown fires. However, concern has been expressed that opening stands might lead to greater drying of surface fuels, contributing to increased fire risk. The objective of this study was to determine whether woody fuel moisture differed between unthinned and thinned mixed-conifer stands. Sections of logs representing the 1000- and 10 000-h fuel sizes were placed at 72 stations within treatment units in the fall (autumn) of 2007. Following snow-melt in 2008, 10-h fuel sticks were added and all fuels were weighed every 1–2 weeks from May until October. Moisture of the 1000- and 10 000-h fuels peaked at the end of May, and then decreased steadily through the season. Moisture of the 10- and 1000-h fuels did not differ between unthinned and thinned stands at any measurement time. The 10 000-h fuel moisture was significantly less in thinned than unthinned stands only in early to mid-May. Overall, even when fuel moisture varied between treatments, differences were small. The long nearly precipitation-free summers in northern California appear to have a much larger effect on fuel moisture than the amount of canopy cover. Fuel moisture differences resulting from stand thinning would therefore not be expected to substantially influence fire behaviour and effects during times of highest fire danger in this environment.

Additional keywords: fire behaviour, fuel reduction treatments, large-diameter fuels, microclimate.


References

Agee JK, Skinner CN (2005) Basic principles of forest fuel reduction treatments. Forest Ecology and Management 211, 83–96.
Basic principles of forest fuel reduction treatments.Crossref | GoogleScholarGoogle Scholar |

Agee JK, Bahro B, Finney MA, Omi PN, Sapsis DB, Skinner CN, van Wagtendonk JW, Weatherspoon CP (2000) The use of shaded fuelbreaks in landscape fire management. Forest Ecology and Management 127, 55–66.
The use of shaded fuelbreaks in landscape fire management.Crossref | GoogleScholarGoogle Scholar |

Brown JK (2003) Coarse woody debris: managing benefits and fire hazard in the recovering forest. USDA Forest Service, Rocky Mountain Research Station, General Technical Report RMRS-105. (Ogden, UT)

Carlson JD, Bradshaw LS, Nelson RM, Bensch RR, Jabrzemski R (2007) Application of the Nelson model to four timelag fuel classes using Oklahoma field observations: model evaluation and comparison with National Fire Danger Rating System algorithms. International Journal of Wildland Fire 16, 204–216.
Application of the Nelson model to four timelag fuel classes using Oklahoma field observations: model evaluation and comparison with National Fire Danger Rating System algorithms.Crossref | GoogleScholarGoogle Scholar |

Countryman CM (1956) Old growth conversion also converts fire climate. Fire Control Notes 17, 15–19.

Countryman CM (1977) Radiation effects on moisture variation in ponderosa pine litter. USDA Forest Service, Pacific Southwest Forest and Range Experiment Station, Research Paper PSW-126. (Berkeley, CA).

Faiella SM, Bailey JD (2007) Fluctuations in fuel moisture across restoration treatments in semi-arid ponderosa pine forests of northern Arizona, USA. International Journal of Wildland Fire 16, 119–127.
Fluctuations in fuel moisture across restoration treatments in semi-arid ponderosa pine forests of northern Arizona, USA.Crossref | GoogleScholarGoogle Scholar |

Finney MA, Seli RC, McHugh CW, Ager AA, Bahro B, Agee JK (2007) Simulation of long-term landscape-level fuel treatment effects on large wildfires. International Journal of Wildland Fire 16, 712–727.
Simulation of long-term landscape-level fuel treatment effects on large wildfires.Crossref | GoogleScholarGoogle Scholar |

Harrington MG (1982) Stand, fuel, and potential fire behavior characteristics in an irregular south-eastern Arizona ponderosa pine stand. USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Research Note RM-418. (Denver, CO)

Ingalsbee T (2005) Fire ecology: issues, management, policy, and opinions. Fire Ecology 1, 85–99.
Fire ecology: issues, management, policy, and opinions.Crossref | GoogleScholarGoogle Scholar |

Keeley JE, McGinnis TW, Bollens KA (2005) Seed germination of Sierra Nevada post-fire chaparral species. Madrono 52, 175–181.
Seed germination of Sierra Nevada post-fire chaparral species.Crossref | GoogleScholarGoogle Scholar |

Kenward MG, Roger JH (1997) Small-sample inference for fixed effects from restricted maximum likelihood. Biometrics 53, 983–997.
Small-sample inference for fixed effects from restricted maximum likelihood.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DyaK2svntVGitw%3D%3D&md5=53aaed8f06a5328dfd101cf15666bca5CAS |

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 |

Littell RC, Milliken GA, Stroup WW, Wolfinger R, Schabenberger O (2006) ‘SAS for Mixed Models.’ 2nd edn (SAS Institute: Cary, NC)

Meyer CL, Sisk TD, Covington WW (2001) Microclimate changes induced by ecological restoration of ponderosa pine forests in northern Arizona. Restoration Ecology 9, 443–452.
Microclimate changes induced by ecological restoration of ponderosa pine forests in northern Arizona.Crossref | GoogleScholarGoogle Scholar |

Murphy JL, Schimke HE, Garber MJ (1965) Timber fuel-breaks and fuel moisture. USDA Forest Service, Pacific Southwest Forest and Range Experiment Station, Research Note PSW-95. (Berkeley, CA)

Ottmar RD, Sandberg DV (1985) Calculating moisture content of 1000-hour timelag fuels in western Washington and western Oregon. USDA Forest Service, Pacific Northwest Forest and Range Experiment Station, Research Paper PNW-336. (Portland, OR)

Pollet J, Omi PN (2002) Effect of thinning and prescribed burning on crown fire severity in ponderosa pine forests. International Journal of Wildland Fire 11, 1–10.
Effect of thinning and prescribed burning on crown fire severity in ponderosa pine forests.Crossref | GoogleScholarGoogle Scholar |

Pook EW, Gill AM (1993) Variation in live and dead fine fuel moisture in Pinus radiata plantations of the Australian Capital Territory. International Journal of Wildland Fire 3, 155–168.
Variation in live and dead fine fuel moisture in Pinus radiata plantations of the Australian Capital Territory.Crossref | GoogleScholarGoogle Scholar |

Pyne SJ, Andrews PL, Laven RD (1996) ‘Introduction to Wildland Fire.’ (Wiley: New York)

Raymond CL, Peterson DL (2005) Fuel treatments alter the effects of wildfire in a mixed-evergreen forest, Oregon, USA. Canadian Journal of Forest Research 35, 2981–2995.
Fuel treatments alter the effects of wildfire in a mixed-evergreen forest, Oregon, USA.Crossref | GoogleScholarGoogle Scholar |

Ritchie M (2005) Ecological research at the Goosenest Adaptive Management Area in north-eastern California. USDA Forest Service, Pacific Southwest Research Station, General Technical Report GTR-192. (Albany, CA)

Ritchie M, Skinner CN, Hamilton TA (2007) Probability of tree survival after wildfire in an interior pine forest of northern California: effects of thinning and prescribed fire. Forest Ecology and Management 247, 200–208.
Probability of tree survival after wildfire in an interior pine forest of northern California: effects of thinning and prescribed fire.Crossref | GoogleScholarGoogle Scholar |

Rothermel RC, Wilson RA, Jr, Morris GA, Sackett SS (1986) Modeling moisture content of fine dead wildland fuels: input to the BEHAVE fire prediction system. USDA Forest Service, Intermountain Research Station, Research Paper INT-359. (Ogden, UT)

Samran S, Woodard PM, Rothwell RL (1995) The effect of soil water on ground fuel availability. Forest Science 41, 255–267.

Schmidt DA, Taylor AH, Skinner CN (2008) The influence of fuels treatment and landscape arrangement on simulated fire behavior, Southern Cascade Range, California. Forest Ecology and Management 255, 3170–3184.
The influence of fuels treatment and landscape arrangement on simulated fire behavior, Southern Cascade Range, California.Crossref | GoogleScholarGoogle Scholar |

Skinner CN, Taylor AH (2006) Southern Cascades Bioregion. In ‘Fire in California’s Ecosystems’. (Eds NG Sugihara, JW van Wagtendonk, KE Shaffer, J Fites-Kaufman, AE Thode) pp. 170–194. (The University of California Press: Berkeley, CA)

Stephens SL, Fry DL, Franco-Vizcaíno E, Collins CM, Moghaddas JJ (2007) Coarse woody debris and canopy cover in an old-growth Jeffrey pine–mixed conifer forest from the Sierra San Pedro Mártir, Mexico. Forest Ecology and Management 240, 87–95.
Coarse woody debris and canopy cover in an old-growth Jeffrey pine–mixed conifer forest from the Sierra San Pedro Mártir, Mexico.Crossref | GoogleScholarGoogle Scholar |

Stephens SL, Moghaddas JJ, Edminster C, Fiedler CE, Haase S, Harrington M, Keeley JE, Knapp EE, McIver JD, Metlen K, Skinner CN, Youngblood A (2009) Fire treatment effects on vegetation structure, fuels, and potential fire severity in western US forests. Ecological Applications 19, 305–320.
Fire treatment effects on vegetation structure, fuels, and potential fire severity in western US forests.Crossref | GoogleScholarGoogle Scholar |

Storck P, Lettenmaier DP, Bolton SM (2002) Measurement of snow interception and canopy effects on snow accumulation and melt in a mountainous maritime climate, Oregon, United States. Water Resources Research 38, 1223–1239.
Measurement of snow interception and canopy effects on snow accumulation and melt in a mountainous maritime climate, Oregon, United States.Crossref | GoogleScholarGoogle Scholar |

Tanskanen H, Venalainen A, Puttonen P, Granstom A (2005) Impact of stand structure on surface fire ignition potential in Picea abies and Pinus sylvestris forests in southern Finland. Canadian Journal of Forest Research 35, 410–420.
Impact of stand structure on surface fire ignition potential in Picea abies and Pinus sylvestris forests in southern Finland.Crossref | GoogleScholarGoogle Scholar |

Taylor AH (2000) Fire regimes and forest changes along a montane forest gradient, Lassen Volcanic National Park, southern Cascade Mountains, USA. Journal of Biogeography 27, 87–104.
Fire regimes and forest changes along a montane forest gradient, Lassen Volcanic National Park, southern Cascade Mountains, USA.Crossref | GoogleScholarGoogle Scholar |

Uzoh FCC, Skinner CN (2009) Effects of creating two forest structures and using prescribed fire on coarse woody debris in north-eastern California, USA. Fire Ecology 5, 1–13.
Effects of creating two forest structures and using prescribed fire on coarse woody debris in north-eastern California, USA.Crossref | GoogleScholarGoogle Scholar |

Van Wagner CE (1977) Conditions for the start and spread of crown fire. Canadian Journal of Forest Research 7, 23–34.
Conditions for the start and spread of crown fire.Crossref | GoogleScholarGoogle Scholar |

Weatherspoon CP (1996) Fire–silviculture relationships in Sierra forests. In ‘Sierra Nevada Ecosystem Project: Final Report to Congress, Vol. II, Assessments and Scientific Basis for Management Options’. pp. 1167–1176. (Centers for Water and Wildland Resources, University of California: Davis, CA)

Whitehead RJ, Russo GL, Hawkes BC, Taylor SW, Brown BN, Barclay HJ, Benton RA (2006) Effect of a spaced thinning in mature lodgepole pine on within-stand microclimate and fine fuel moisture content. In ‘Fuels Management-How to Measure Success: Conference Proceedings’. (Eds PL Andrews, BW Butler) USDA Forest Service, Rocky Mountain Research Station, Proceedings RMRS-P-41, pp. 523–536. (Fort Collins, CO)

Youngblood A, Wright CS, Ottmar RD, McIver JD (2008) Changes in fuelbed characteristics and resulting fire potentials after fuel reduction treatments in dry forests of the Blue Mountains, north-eastern Oregon. Forest Ecology and Management 255, 3151–3169.
Changes in fuelbed characteristics and resulting fire potentials after fuel reduction treatments in dry forests of the Blue Mountains, north-eastern Oregon.Crossref | GoogleScholarGoogle Scholar |