Bark heat resistance of small trees in Californian mixed conifer forests: Testing some model assumptions
An essential component to models of fire-caused tree mortality is an assessment of cambial damage. Cambial heat resistance has been traditionally measured in large overstory trees with thick bark, although small trees have thinner bark and thus are more sensitive to fire. We undertook this study to determine if current models of bark heat transfer are applicable to small trees (<20 cm diameter at breast height (dbh)). We performed this work in situ on four common species in the mixed conifer forests of the Sierra Nevada, California.
The allometric relationship between bole diameter and bark thickness for each species was linear, even for very small trees (5 cm dbh). Heating experiments demonstrated that bark thickness was the primary determinant of cambial heat resistance. We found only slight, but statistically significant, among species differences in bark thermal properties. Our most significant finding was that small trees were more resistant to heating than expected from commonly used models of bark heat transfer. Our results may differ from those of existing models because we found smaller trees to have a greater proportion of inner bark, which appears to have superior insulating properties compared to outer bark. From a management perspective, growth projections suggest that a 50-year fire-free interval may allow some fire intolerant species to achieve at least some degree of cambial heat resistance in the Sierra Nevada.
Citation Information
Publication Year | 2003 |
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Title | Bark heat resistance of small trees in Californian mixed conifer forests: Testing some model assumptions |
DOI | 10.1016/S0378-1127(02)00554-6 |
Authors | Phillip J. van Mantgem, Mark Schwartz |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Forest Ecology and Management |
Index ID | 1008219 |
Record Source | USGS Publications Warehouse |
USGS Organization | Western Ecological Research Center |