The influence of residue removal and prescribed fire on distributions of forest nutrients.

Abstract

The effects of two levels of residue removal (removal of all woody material larger than 15 x 180 cm and 10 x 120 cm) on the distribution of nitrogen and sulfur on the forest site and the added effects of post-harvest prescribed fire on those distributions were studied at two sites in the Cascade Range in Oregon. Nutrients lost from increased removal of residue were small compared with nutrients removed in merchantable timber. Differences in the amount of nutrient capital removed during harvest between the two levels of residue removal amounted to 1 percent of the total site nitrogen and 4 percent of the total site sulfur. The amount of nutrient lost during fire depended not only on residue levels, but also on moisture content of residue and duff. At the site where both treatments had the same moisture levels, the unit with less residue removed by harvest lost 7 percent more nitrogen by the combination of harvest and prescribed burn. It appears that nutrient losses due to fire may be mitigated by increased residue removal.

Citation

Little; S.N.; Klock, G.O. 1985. The influence of residue removal and prescribed fire on distributions of forest nutrients. Res. Pap. PNW-RP-338. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 20 p