SITE PREPARATION BURNING TO IMPROVE SOUTHERN APPALACHIAN PINE HARDWOOD STANDS - ABOVEGROUND BIOMASS, FOREST FLOOR MASS, AND NITROGEN AND CARBON POOLS

On three sites in the southern Appalachians, stands characterized by s parse overstories and dense Kalmia latifolia L. shrub layers were fell ed in early summer and burned in early fall. Amounts of aboveground ve getation and forest floor mass, nitrogen (N), and carbon (C) were meas ured before and after treatment by sampling wood, foliage, herbs, gras ses, and forest floor (Oi and Oe + Oa layers). Burning decreased woody mass by 48 to 60% across the three sites. The most intense burn reduc ed mass from 180 to 70 Mg . ha-1, and N and C losses were 300 kg . ha- 1 and 52 Mg . ha-1, respectively. Significant losses of mass, N, and C occurred in the Oi layer, but not in the Oe + Oa layer. Foliage, herb s, and grasses were totally consumed by the fires. Total aboveground N losses across sites ranged from 193 to 480 kg . ha-1. These losses ma y be significant because N availability is low on these sites. Variati ons in patterns of mass, N, and C consumption were related to differen ces in amounts, types, size distributions, and moisture contents of fu els.