Burning rate of smoldering peat
Document Type: Journal Article
Author(s): William H. Frandsen
Publication Year: 1991

Cataloging Information

  • bulk density
  • CO - carbon monoxide
  • combustion
  • decay
  • decomposition
  • duff
  • fuel loading
  • ground fires
  • heat
  • heavy fuels
  • ignition
  • inorganic ratio
  • Larix occidentalis
  • litter
  • lodgepole pine
  • moisture
  • mortality
  • mosses
  • organic matter
  • peat
  • peat fires
  • peatlands
  • Pinus contorta
  • polyurethanes
  • rate of spread
  • sampling
  • smoldering
  • soil organic matter
  • soil organisms
  • soil temperature
  • sphagnum
  • statistical analysis
  • surface fires
  • temperature
  • universal burning rate
  • western larch
Record Maintained By:
Record Last Modified: June 1, 2018
FRAMES Record Number: 3845
Tall Timbers Record Number: 7943
TTRS Location Status: In-file
TTRS Call Number: Fire File
TTRS Abstract Status: Okay, Fair use, Reproduced by permission

This bibliographic record was either created or modified by the Tall Timbers Research Station and Land Conservancy and is provided without charge to promote research and education in Fire Ecology. The E.V. Komarek Fire Ecology Database is the intellectual property of the Tall Timbers Research Station and Land Conservancy.


Smoldering ground fires spread slowly (about 3 cm h-1) and can raise mineral soil temperatures above 300 degrees C for several hours with peak temperatures near 600 degrees C, resulting in decomposition of organic material and the death of soil organisms. Smoldering ground fire has potential for reigniting surface fire long after the main front has passed. The rate of smoldering was examined with the Canadian sphagnum peat moss as a representative fuel. The time to burn a known amount of organic mass was monitored for different organic bulk densities and moistures and inorganic contents. Organic bulk densities were comparable to the field and ranged from 90 to 180 kg m-3. Moisture and inorganic contents were expresses as mass ratios relative to the organic mass and covered the range of sustained smoldering combustion. Moisture ratios: Rm. ran up to 0.8 and inorganic ratios, RI, up to 4.0. The burning rate is independent of the organic bulk density. A universal burning rate, the unit area burn rate (UBR), was obtained by normalizing the burning rate to the area of the burning surface. It is expressed as follows: UBR = 0.27-0.997 Rm - 0.033(RI - D) g cm-2 h-1. Where D = RI if RI < 1.0, and D = 1.0 if RI > 1.0

Online Link(s):
Link to this document (425 KB; pdf)
Frandsen, William H. 1991. Burning rate of smoldering peat. Northwest Science 65(4):166-172.