A comparison of two methods for estimating conifer live foliar moisture content
W. Matt Jolly A B and Ann M. Hadlow A
+ Author Affiliations
- Author Affiliations
A US Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory, 5775 Highway 10 W, Missoula, MT 59808, USA.
B Corresponding author. Email: mjolly@fs.fed.us
International Journal of Wildland Fire 21(2) 180-185 https://doi.org/10.1071/WF11015
Submitted: 25 January 2011 Accepted: 6 June 2011 Published: 30 November 2011
Abstract
Foliar moisture content is an important factor regulating how wildland fires ignite in and spread through live fuels but moisture content determination methods are rarely standardised between studies. One such difference lies between the uses of rapid moisture analysers or drying ovens. Both of these methods are commonly used in live fuel research but they have never been systematically compared to ensure that they yield similar results. Here we compare the foliar moisture content of Pinus contorta (lodgepole pine) at multiple sites for an entire growing season determined using both oven-drying and rapid moisture analyser methods. We found that moisture contents derived from the rapid moisture analysers were nearly identical to oven-dried moisture contents (R2 = 0.99, n = 68) even though the rapid moisture analysers dried samples at 145°C v. oven-drying at 95°C. Mean absolute error between oven-drying and the rapid moisture analysers was low at 2.6% and bias was 0.62%. Mean absolute error was less than the within-sample variation of an individual moisture determination method and error was consistent across the range of moisture contents measured. These results suggest that live fuel moisture values derived from either of these two methods are interchangeable and it also suggests that drying temperatures used in live fuel moisture content determination may be less important than reported by other studies.
Additional keywords: Computrac, fuel moisture, live fuels, oven-drying, rapid moisture analyser.
References
Altman D, Bland J (1983) Measurement in medicine; the analysis of method comparison studies. The Statistician 32, 307–317.| Measurement in medicine; the analysis of method comparison studies.Crossref | GoogleScholarGoogle Scholar |
Arizona Instruments LLC (2002) ‘Computrac MAX 2000XL Moisture Analyzer User’s Manual.’ (Arizona Instruments LLC: Chandler, AZ)
Brenner J (2002) Measuring live fuel moistures in Florida: standard methods and procedures. (Florida Division of Forestry, Department of Agriculture and Consumer Services). Available at http://www.fl-dof.com/wildfire/live_fuel_moisture/lfm_pdfs/procedures.pdf [Verified 23 November 2011]
Castillo JM, Enriques G, Nakahara M, Weise D, Ford L, Moraga R, Vihnanek R (2007) Effects of cattle grazing, glyphosate, and prescribed burning on fountain grass fuel loading in Hawai’i. In ‘Proceedings 23rd Tall Timbers Fire Ecology Conference: Fire in Grassland and Shrubland Ecosystems’, 17–20 October 2005, Bartlesville, OK. (Eds RE Masters, KEM Galley) Tall Timbers Research Station, Proceedings FC23, pp. 230–239. (Tallahassee, FL)
Chrosciewicz Z (1986) Foliar moisture content variations in four coniferous tree species of central Alberta. Canadian Journal of Forest Research 16, 157–162.
| Foliar moisture content variations in four coniferous tree species of central Alberta.Crossref | GoogleScholarGoogle Scholar |
Countryman D, Dean W (1979) Measuring moisture content in living chaparral: a field user’s manual. USDA Forest Service, Pacific Southwest Experiment Station, General Technical Report GTR-PSW-36. (Berkeley, CA)
Dimitrakopoulos AP, Papaioannou KK (2001) Flammability assessment of Mediterranean forest fuels. Fire Technology 37, 143–152.
| Flammability assessment of Mediterranean forest fuels.Crossref | GoogleScholarGoogle Scholar |
Kozlowski TT, Pallardy SG (1979) ‘The Physiology of Woody Plants.’ (Academic Press: San Diego, CA)
Little CHA (1970) Seasonal changes in carbohydrate and moisture content in needles of balsam fir (Abies balsamea). Canadian Journal of Botany 48, 2021–2028.
| Seasonal changes in carbohydrate and moisture content in needles of balsam fir (Abies balsamea).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE3MXjvFWgtQ%3D%3D&md5=1f94a776b2cb71d7b5a6b9a16e4f14d2CAS |
Manzello SL, Cleary TG, Shields JR, Maranghides A, Mell W, Yang JC (2008) Experimental investigation of firebrands: generation and ignition of fuel beds. Fire Safety Journal 43, 226–233.
| Experimental investigation of firebrands: generation and ignition of fuel beds.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXktlejtrY%3D&md5=6898c3d95cc8444d51df01ed3c5c0a41CAS |
Matthews S (2010) Effect of drying temperature on fuel moisture content measurements. International Journal of Wildland Fire 19, 800–802.
| Effect of drying temperature on fuel moisture content measurements.Crossref | GoogleScholarGoogle Scholar |
Nelson RM Jr (2001) Water relations of forest fuels. In ‘Forest Fires: Behavior and Ecological Effects’. (Eds EA Johnson, K Miyanishi) pp. 79–149. (Academic Press: London, UK)
Norum R, Miller M (1984) Measuring the fuel moisture content in Alaska: standard methods and procedures. USDA Forest Service, Pacific Northwest Forest and Range Experiment Station, General Technical Report GTR-PNW-171. (Portland, OR)
Pellizzaro G, Duce P, Ventura A, Zara P (2007) Seasonal variations of live moisture content and ignitability in shrubs of the Mediterranean Basin. International Journal of Wildland Fire 16, 633–641.
| Seasonal variations of live moisture content and ignitability in shrubs of the Mediterranean Basin.Crossref | GoogleScholarGoogle Scholar |
Philpot CW, Mutch RW (1971) The seasonal trends in moisture content, ether extractives, and energy of ponderosa pine and Douglas-fir needles. USDA Forest Service, Intermountain Forest and Range Experiment Station, Research Paper INT-102. (Ogden, UT)
Pickett BM, Isackson C, Wunder R, Fletcher TH, Butler BW, Weise DR (2010) Experimental measurements during combustion of moist individual foliage samples. International Journal of Wildland Fire 19, 153–162.
| Experimental measurements during combustion of moist individual foliage samples.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXjvF2msLw%3D&md5=96dc2c8caba02377c458f2679631f8feCAS |
Pook EW, Gill AM (1993) Variation of live and dead fine fuel moisture in Pinus radiata plantations of the Australian Capital Territory. International Journal of Wildland Fire 3, 155–168.
| Variation of live and dead fine fuel moisture in Pinus radiata plantations of the Australian Capital Territory.Crossref | GoogleScholarGoogle Scholar |
Ruiz González AD, Vega Hidalgo JA, Ãlvarez Gonzalez JG (2009) Construction of empirical models for predicting Pinus sp. dead fine fuel moisture in NW Spain. I: Response to changes in temperature and relative humidity. International Journal of Wildland Fire 18, 71–83.
| Construction of empirical models for predicting Pinus sp. dead fine fuel moisture in NW Spain. I: Response to changes in temperature and relative humidity.Crossref | GoogleScholarGoogle Scholar |
Samuelsson R, Nilsson C, Burvall J (2006) Sampling and GC-MS as a method for analysis of volatile organic compounds (VOC) emitted during oven-drying of biomass materials. Biomass and Bioenergy 30, 923–928.
| Sampling and GC-MS as a method for analysis of volatile organic compounds (VOC) emitted during oven-drying of biomass materials.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XhtVyksLvM&md5=094bfd62666bfefda6df5d87bc94cc8dCAS |
Sokal RR, Rohlf FJ (1997) ‘Biometry.’ (WH Freeman and Company: New York)
Southwest Area (2004) ‘Southwest Area Fuel Moisture Monitoring Program: Standard Methods and Procedures.’ (Albequerque, NM) Available at ftp://ftp2.fs.fed.us/incoming/wo_fam/PattyJ/Fuel%20Moisture%20Sampling/SWA_FM_Monitoring.pdf [Verified 20 September 2011]
Sun L, Zhou X, Mahalingam S, Weise DR (2006) Comparison of burning characteristics of live and dead chaparral fuels. Combustion and Flame 144, 349–359.
| Comparison of burning characteristics of live and dead chaparral fuels.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXhtlertbrJ&md5=5d20ed5f08acc1f2ca5fb22a16c1aa34CAS |
Thompson SK (2002) ‘Sampling.’ (Wiley: New York)
Viegas DX, Viegas M, Ferreira AD (1992) Moisture content of fine forest fuels and fire occurrence in central Portugal. International Journal of Wildland Fire 2, 69–86.
| Moisture content of fine forest fuels and fire occurrence in central Portugal.Crossref | GoogleScholarGoogle Scholar |
Weise DR, Hartford RA, Mahaffey L (1998) Assessing live fuel moisture for fire management applications. In ‘Proceedings 20th Tall Timbers Fire Ecology Conference: Fire in Ecosystem Management: Shifting the Paradigm from Suppression to Prescription’, 7–10 May 1996, Boise, ID. (Eds TR Pruden, LA Brennan) Timbers Research Station, Proceedings FC20, pp. 49–55. (Tall Tallahassee, FL) available at http://www.fs.fed.us/psw/publications/weise/psw_1998_weise000.pdf [Verified 23 November 2011]
Weise DR, Zhou X, Sun L, Mahalingam S (2005) Fire spread in chaparral – ‘go or no-go?’ International Journal of Wildland Fire 14, 99–106.
| Fire spread in chaparral – ‘go or no-go?’Crossref | GoogleScholarGoogle Scholar |
Xanthopoulos G, Wakimoto RH (1993) A time to ignition–temperature–moisture relationship for branches of three western conifers. Canadian Journal of Forest Research 23, 253–258.
| A time to ignition–temperature–moisture relationship for branches of three western conifers.Crossref | GoogleScholarGoogle Scholar |
