International Journal of Wildland Fire International Journal of Wildland Fire Society
Journal of the International Association of Wildland Fire

Testing and classification of individual plants for fire behaviour: plant selection for the wildland–urban interface

Robert H. White A and Wayne C. Zipperer B C

A USDA, Forest Service, Forest Products Laboratory, One Gifford Pinchot Drive, Madison, WI 53726, USA. Email:

B USDA Forest Service, PO Box 110806, Gainesville, FL 32611, USA.

C Corresponding author. Email:

International Journal of Wildland Fire 19(2) 213-227
Submitted: 29 August 2007  Accepted: 10 July 2008   Published: 31 March 2010


Knowledge of how species differ in their flammability characteristics is needed to develop more reliable lists of plants recommended for landscaping homes in the wildland–urban interface (WUI). As indicated by conflicting advice in such lists, such characterisation is not without difficulties and disagreements. The flammability of vegetation is often described as having four components (ignitability, combustibility, sustainability and consumability). No standards or generally recognised test procedures exist for evaluating these components in plants. Some measurements of flammability include times for ignition, rate of flame spread, flame height and heat release rate. Often, the fire behaviour characteristics of a plant are derived from its physical and chemical characteristics. Thermogravimetric analysis and other thermal analyses of ground samples have long been used to characterise the thermal degradation of vegetation. More recently, researchers have used the oxygen consumption methodology to measure the heat released due to combustion of the vegetation. Although oxygen consumption calorimetry is an improvement in characterising plant flammability, translation of laboratory results to field conditions can be problematic and tests can be expensive.

Additional keywords: calorimetry, flammability, oxygen consumption, vegetation.


Albini FA (1980) Thermochemical properties of flame gases from fine wildland fuels. USDA Forest Service, Intermountain Forest and Range Research Station, Research Paper INT-243. (Ogden, UT)

Alessio GAPeñuelas JLlusià JOgaya REstiarte MDe Lillis M2008Influence of water and terpenes on flammability in some dominant Mediterranean species.International Journal of Wildland Fire17274286doi:10.1071/WF07038

Anderson HE1970Forest fuel ignitibility.Fire Technology6312319, 322doi:10.1007/BF02588932

Anonymous 2005Committee on fire standards launches subcommittee on external fire exposure tests.ASTM Standardization News331016

Apte VB (Ed.) (2006) ‘Flammability testing of materials used in construction, transport and mining.’ (Woodhead Publishing Limited: Cambridge, UK)

Babrauskas V1984Development of the cone calorimeter – a bench scale heat release rate apparatus based on oxygen consumption.Fire and Materials88195

Babrauskas V (2002a) The cone calorimeter. In ‘The SFPE handbook of fire protection engineering’. 3rd edn, pp. 3-63–3-81. (National Fire Protection Association: Quincy, MA)

Babrauskas V (2002b) Heat release rates. In ‘The SFPE handbook of fire protection and engineering’. 3rd edn, pp. 3-1–3-37. (National Fire Protection Association: Quincy, MA)

Babrauskas V (2003) ‘Ignition handbook.’ (Fire Science Publishers: Issaquah, WA)

Babrauskas V2006Effective heat of combustion for flaming combustion of conifers.Canadian Journal of Forest Research36659663doi:10.1139/X05-253

Baker E, Woycheese JP (2007) Burning characteristics of Douglas-fir trees: scaling of individual tree fire based on tree size. In ‘Conference papers fire and materials, 2007, 10th international conference’, 29–31 January 2007, San Francisco, CA. (CD-ROM) (Interscience Communications: London)

Baptiste L (1992) ‘Firescape – landscaping to reduce fire hazard.’ (East Bay Municipal Utility District: Oakland, CA)

Beall FC1969Thermogravimetric analysis of wood lignin and hemicelluloses.Wood and Fiber1215226

Beall FC, Eickner HW (1970) Thermal degradation of wood components: a review of the literature. USDA Forest Service, Forest Product Laboratory, Research Paper FPL 130. (Madison, WI)

Behm ALDuryea MLLong AJZipperer WC2004aFlammability of native understory species in pine flatwood and hardwood hammock ecosystems and implications for the wildland–urban interface.International Journal of Wildland Fire13355365

Behm AL, Long AJ, Monroe MC, Randall CK, Zipperer WC, Hermansen-Baez LA (2004b) Fire in the wildland–urban interface: preparing a firewise plant list for WUI residents. University of Florida, Institute of Food and Agricultural Services, Florida Cooperative Extension Service Circular 1453. (Gainesville, FL)

Bilbao RMastral JFCeamanos JAldea ME1996Modeling of the pyrolysis of wet wood.Journal of Analytical and Applied Pyrolysis368197doi:10.1016/0165-2370(95)00918-3

Blank RRWhite RHZiska LH2006Combustion properties of Bromus tectorum L.: influence of ecotype and growth under four CO2 concentrations.International Journal of Wildland Fire15227236doi:10.1071/WF05055

Clark FRS1981Fire spread tests – a critique.Fire Technology417992

County of Los Angeles Fire Department (1998) Fuel modification guidelines for projects located in fire zone 4 or very high fire hazard severity. County of Los Angeles Fire Department, Prevention Bureau, Forestry Division, Brush Clearance Section. (Los Angeles, CA)

Damant GHNurbakhsh S1994Christmas trees – what happens when they ignite?Fire and Materials18916

Detweiler AJ, Fitzgerald S (2006) Fire-resistant plants for home landscapes: selecting plants that may reduce your risk from wildfire. Oregon State University Extension Service, Pacific Northwest Extension (PNW) 590. (Corvallis, OR)

Dibble ACWhite RHLebow PK2007Combustion characteristics of north-eastern USA vegetation tested in the cone calorimeter: invasive versus non-invasive plants.International Journal of Wildland Fire16426443doi:10.1071/WF05103

Dietenberger M2002Update for combustion properties of wood components.Fire and Materials26255267doi:10.1002/FAM.807

Dimitrakopoulos AP2001aA statistical classification of Mediterranean species based on their flammability components.International Journal of Wildland Fire10113118doi:10.1071/WF01004

Dimitrakopoulos AP2001bThermogravimetric analysis of Mediterranean plant species.Journal of Analytical and Applied Pyrolysis60123130doi:10.1016/S0165-2370(00)00164-9

Dimitrakopoulos APPanov PI2001Pyric properties of some dominant Mediterranean vegetation species.International Journal of Wildland Fire102327doi:10.1071/WF01003

Dimitrakopoulos APPapaioannou KK2001Flammability assessment of Mediterranean forest fuels.Fire Technology37143152doi:10.1023/A:1011641601076

Doran JD, Randall CK, Long AJ (2004) Fire in the wildland–urban interface: selecting and maintaining firewise plants for landscaping. University of Florida, Institute of Food and Agricultural Services, Florida Cooperative Extension Service Circular 1445. (Gainesville, FL)

Emmons HW1974Fire and fire protection.Scientific American2312127

Enninful EK, Torvi DA (2005) Effects of moisture on smoke production and heat release rates of vegetation. In ‘Proceedings of The Combustion Institute, Canadian Section 2005 Spring Meeting’, 15–19 May 2005, Dalhousie University, Halifax, NS, Canada. (Eds P Amyotte, M Pegg) pp. 273–278. (The Combustion Institute, Canadian Section)

Etlinger MGBeall FC2004Development of a laboratory protocol for fire performance of landscape plants.International Journal of Wildland Fire13479488

Evans DD, Rehm RG, Baker ES (2004) Physics-based modeling for WUI fire spread – simplified model algorithm for ignition of structures by burning vegetation. USDC National Institute of Standards and Technology NISTIR 7179. (Gaithersburg, MD)

Fernandes PMRego FC1998A new method to estimate fuel surface area-to-volume ratio using water immersion.International Journal of Wildland Fire8121128doi:10.1071/WF9980121

Fogarty LG (2001) A flammability guide for some common New Zealand native tree and shrub species. Forest Research (Rotorua) in association with the New Zealand Fire Service Commission and National Rural Fire Authority, Forest Research Bulletin No. 197, Forest and Rural Fire Scientific and Technical Series, Report No. 6. (Wellington)

Fonda RW2001Burning characteristics of needles from eight pine species.Forest Science47390396

Gill AM, Moore PHR (1996) Ignitibility of leaves of Australian plants. CSIRO Plant Industry, Centre for Plant Biodiversity Research. (Canberra)

Hough WA (1969) Caloric value of some forest fuels of the southern United States. USDA Forest Service, Southeastern Forest Experiment Station, Research Note SE-120. (Asheville, NC)

Huggett C1980Estimation of rate of heat release by means of oxygen consumption measurements.Fire and Materials46165

Janssens M (2002) Calorimetry. In ‘The SFPE handbook of fire protection engineering’. 3rd edn, pp. 3-38–3-62. (National Fire Protection Association: Quincy, MA)

Liodakis SBakirtzis DLois E2002TG and autoignition studies on forest fuels.Journal of Thermal Analysis and Calorimetry69519528doi:10.1023/A:1019907706137

Long A, Hinton B, Zipperer W, Hermansen-Baez A, Maranghides A, Mell W (2006) Quantifying and ranking the flammability of ornamental shrubs in the southern United States In ‘2006 Fire Ecology and Management Congress Proceedings. Quantifying and ranking the flammability of ornamental shrubs in the southern United States’. (DVD) (The Association for Fire Ecology and Washington State University Extension: San Diego, CA)

Lubin DM, Shelly JR (Eds) (1997) Defensible space landscaping in the urban/wildland interface: a compilation of fire performance ratings of residential landscape plants. University of California, Forest Products Laboratory, Internal Report No. 36.01.137. (Richmond, CA)

Lyon REWalters RN2004Pyrolysis combustion flow calorimetry.Journal of Analytical and Applied Pyrolysis712746doi:10.1016/S0165-2370(03)00096-2

Lyon RE, Walters RN (2007) Screening flame-retardants for plastics using microscale combustion calorimetry. In ‘Proceedings of the 18th annual conference on recent advances in flame retardancy of polymeric materials’, 21–23 May 2007, Stamford, CT. (Ed. M Lewin) Vol. 1, pp. 74–93. (BCC Research: Norwalk, CT)

Mak EHT1988Measuring foliar flammability with the limiting oxygen index method.Forest Science34523529

Manzello SLMaranghides AMell WE2007Firebrand generation from burning vegetation.International Journal of Wildland Fire16458462

Martin RE, Gordon DA, Gutierrez ME, Lee DS, Molina DM, Schroeder RA, Sapsis DB, Stephens SL, Chambers M (1994) Assessing the flammability of domestic and wildland vegetation. In ‘Proceedings of the 12th conference on fire and forest meteorology’, 26–28 October 1993, Jekyll Island, GA. pp. 130–137. (Society of American Foresters: Bethesda, MD)

Montgomery KRCheo PC1971Effect of leaf thickness on ignitibility.Forest Science17475478

Natori AKakae NKitahori JTsuchihashi TAbe TNagaoka TOhmiya YHarada K2006Development of a simple estimation method of heat release rate based on classification of common combustibles in category groups.Fire Science and Technology253154

Orange County Fire Authority (2001) Guideline for fuel modification plans and maintenance program. Orange County Fire Authority, Guideline C-05 dated 10 April 2001. (Orange, CA)

Philpot CW (1969) Seasonal changes in heat content and ether extractive content of chamise. USDA Forest Service, Intermountain Forest and Range Experiment Station, Research Paper INT-61. (Ogden, UT)

Pyne SJ, Andrews PL, Laven RD (1996) ‘Introduction to Wildland Fire.’ 2nd edn. (Wiley: New York)

Radeloff VCHammer RBStewart SIFried JSHolcomb SSMcKeefry JF2005The wildland–urban interface in the United States.Ecological Applications15799805doi:10.1890/04-1413

Rothermel RC (1972) A mathematical model for predicting fires spread in wildland fuels. USDA Forest Service, Intermountain Forest and Range Experiment Station, Research Paper INT-115. (Ogden, UT)

Sandberg DVOttmar RDCushon GH2001Characterizing fuels in the 21st century.International Journal of Wildland Fire10381387doi:10.1071/WF01036

Särdqvist S (1993) Initial fires – RHR, smoke production and CO generation from single items and room fire tests. Lund University, Institute of Technology, Department of Fire Safety Engineering. (Lund, Sweden)

Shafizadeh FChin PPSDeGroot WF1977Effective heat content of green forest fuels.Forest Science238189

Stephens SL, Gordon DA, Martin RE (1994) Combustibility of selected domestic vegetation subjected to desiccation. In ‘Proceedings of the 12th Conference on Fire and Fire Meteorology’, 26–28 October 1993, Jekyll Island, GA. pp. 565–571. (Society of American Foresters: Bethesda, MD)

Stroup DW, DeLauter L, Lee J, Roadarmel G (1999) Scotch pine Christmas tree fire tests, Report of Test FR 4010. USDC, National Institute of Standards and Technology, 1 December 1999. (Gaithersburg, MD)

Sun LZhou XMahalingam SWeise DR2006Comparison of burning characteristics of live and dead chaparral fuels.Combustion and Flame144349359

Susott RA1982aCharacterization of the thermal properties of forest fuels by combustible gas analysis.Forest Science28404420

Susott RA1982bDifferential scanning calorimetry of forest fuels.Forest Science28839851

Susott RADeGroot WFShafizadeh F1975Heat content of natural fuels.Journal of Fire and Flammability6311325

van Wagtendonk JWSydoriak WMBenedict JM1998Heat content variation of Sierra Nevada conifers.International Journal of Wildland Fire8147158

Weise DRWhite RHBeall FCEtlinger M2005Use of the cone calorimeter to detect seasonal differences in selected combustion characteristics of ornamental vegetation.International Journal of Wildland Fire14321338doi:10.1071/WF04035

White RH1987Effect of lignin content and extractives on the higher heating value of wood.Wood and Fiber Science19446452

White RH, DeMars D, Bishop M (1997) Flammability of Christmas trees and other vegetation. In ‘Proceedings of the 24th international conference on fire safety’, 21–24 July 1997, Columbus, OH. (Ed. CJ Hilado) pp. 99–110. (Products Safety Corporation: Sissonville, WV)

White RH, Weise DR, Mackes K, Dibble AC (2002) Cone calorimeter testing of vegetation: an update. In ‘Proceedings of the 35th international conference on fire safety’, 22–24 July 2002, Columbus, OH. (Ed. CJ Hilado) pp. 1–12. (Products Safety Corporation: Sissonville, WV)

Williamson NMAgee JK2002Heat content variation of interior Pacific Northwest conifer foliage.International Journal of Wildland Fire119194

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