A comparison of five sampling techniques to estimate surface fuel loading in montane forests*
Pamela G. Sikkink A C and Robert E. Keane BA Systems for Environmental Management, PO Box 8868, Missoula, MT 59807, USA.
B USDA Forest Service, Rocky Mountain Research Station, Missoula Fire Sciences Laboratory, 5775 W US Highway 10, Missoula, MT 59808, USA.
C Corrresponding author. Email: pgsikkink@fs.fed.us
International Journal of Wildland Fire 17(3) 363-379 https://doi.org/10.1071/WF07003
Submitted: 5 January 2007 Accepted: 11 August 2007 Published: 23 June 2008
Abstract
Designing a fuel-sampling program that accurately and efficiently assesses fuel load at relevant spatial scales requires knowledge of each sample method’s strengths and weaknesses. We obtained loading values for six fuel components using five fuel load sampling techniques at five locations in western Montana, USA. The techniques included fixed-area plots, planar intersect, photoloads, a photoload macroplot, and a photo series. For each of the six fuels, we compared (1) the relative differences in load values among techniques and (2) the differences in load between each method and a reference sample. Totals from each method were rated for how much they deviated from totals for the reference in each fuel category. The planar-intersect method, which used 2.50 km of transects, was rated best overall for assessing the six fuels. Bootstrapping showed that at least 1.50 km of transect were needed to obtain estimates that approximate the reference sample. A newly developed photoload method, which compared fuel conditions on the forest floor with sets of pictures calibrated for load by fuel type, compared well with the reference and planar intersect. The commonly used photo series consistently produced higher mean load estimates than any other method for total fine woody debris (0.05–0.20 kg m–2) and logs (0.50–1.25 kg m–2).
Additional keywords: fuel inventory, fuel sampling, line intersect, photoload, photo series.
* The use of trade or firm names in the current paper is for reader information and does not imply endorsement by the US Department of Agriculture of any product or service. This paper was written and prepared by US Government employees on official time; therefore, it is in the public domain and not subject to copyright.
Acknowledgements
We thank Steve Slaughter and Laura Ward, Ninemile Ranger District, Lolo National Forest and Laurie Dickinson and Curtis Johnson from USDA Forest Service Rocky Mountain Research Station Missoula Fire Sciences Laboratory for sampling support. We also thank our coworkers from the USDA Forest Service Rocky Mountain Research Station and Systems for Environmental Management, who diligently sampled these sites as part of the field crews; Jim Kautz and Ian Grob from the Missoula Technology and Development Center, who granted use of the Center’s photo laboratory and technical and creative assistance to create the photo sequences; Kathleen Gray, who provided statistical support; and Duncan Lutes, Helen Smith, Rudy King, and two anonymous reviewers, whose comments greatly improved the present manuscript.
Bate LJ, Torgersen TR, Wisdom MJ , Garton EO (2004) Performance of sampling methods to estimate log characteristics for wildlife. Forest Ecology and Management 199, 83–102.
Delisle GP, Woodard PM, Titus SJ , Johnson AF (1988) Sample size and variability of fuel weight estimates in natural stands of lodgepole pine. Canadian Journal of Forest Research 18, 649–652.
| Crossref | GoogleScholarGoogle Scholar |
Fosberg MA (1970) Drying rates of heartwood below fiber saturation. Forest Science 16, 57–63.
Hazard JW , Pickford SG (1978) Simulation studies on line intersect sampling of forest residue. Forest Science 24, 469–483.
Jalonen J, Vanha-Majamaa I , Tonteri T (1998) Optimal sample and plot size for inventory of field and ground layer vegetation in a mature Myrtillus-type boreal spruce forest. Annales Botanici Fennici 35, 191–196.
Pickford SG , Hazard JW (1978) Simulation studies in the line intersect sampling of forest residue. Forest Science 24, 469–483.
Reynolds MR (1984) Estimating the error in model predictions. Forest Science 30, 454–469.
Sandberg DV, Ottmar RD , Cushon GH (2001) Characterizing fuels in the 21st century. International Journal of Wildland Fire 10, 381–387.
| Crossref | GoogleScholarGoogle Scholar |
Stahl G (1998) Transect relascope sampling – a method for the quantification of coarse woody debris. Forest Science 44, 58–63.
Thorne MS, Skinner QD, Smith MA, Rodgers JD, Laycock WA , Cerekci SA (2002) Evaluation of a technique for measuring canopy volume of shrubs. Journal of Range Management 55, 235–241.
| Crossref | GoogleScholarGoogle Scholar |
van Wagtendonk JW, Benedict JM , Sydoriak WM (1996) Physical properties of woody fuel particles of Sierra Nevada conifers. International Journal of Wildland Fire 6, 117–123.
| Crossref | GoogleScholarGoogle Scholar |
Van Wagner CE (1968) The line intersect method in forest fuel sampling. Forest Science 14, 20–26.
Waddell KL (2002) Sampling coarse woody debris for multiple attributes in extensive resource inventories. Ecological Indicators 1, 139–153.
| Crossref | GoogleScholarGoogle Scholar |
Warren WG , Olsen PF (1964) A line intersect technique for assessing logging waste. Forest Science 10, 267–276.
Williams MS , Gove JH (2003) Perpendicular distance sampling: an alternative method for sampling downed coarse woody debris. Canadian Journal of Forest Research 33, 1564–1579.
| Crossref | GoogleScholarGoogle Scholar |
Woldendorp G, Keenan RJ, Barry S , Spencer DR (2004) Analysis of sampling methods for coarse woody debris. Forest Ecology and Management 198, 133–148.
| Crossref | GoogleScholarGoogle Scholar |
Accessory publication
Table A1. Comparing fuel load totals at five montane-forest sites using five fuel-sampling techniques
This table is available from the International Journal of Wildland Fire website.
