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.


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