Impact of Fire On Wood Decomposition in Forest Soils of Western North America.

Due to past fire exclusion practices and recent drought conditions in western North America, the number of large, high intensity fires has increased in the last decade.  Consequently, there has been much interest on the effects such fires have on soil organic matter pools and the decomposition of new and residual OM after the fires. While most decomposition studies after fire have concentrated on surface leaf litter, much less is known on mineral soil.  As part of a comprehensive study on the impact of wild and prescribed fire on soil physical, chemical and biological properties in western North American forests, we used “standard” wood stakes as an “index” of fire effect on organic matter decomposition across a range forest types and mineral soil conditions. We will give the results from studies currently underway in different U.S. forest ecosystems on the impact of wildfire on wood decomposition rates in mineral soil.