Pre and post-burn forest floor survey of Jacobs Branch and Devils Den burn sites, 1990-1992

Changes in aboveground and forest floor mass, carbon (C), and nitrogen (N) pools were quantified on three sites in the southern Appalachians 2 yr after felling and burning. Before felling and burning, stands were characterized by sparse overstories and dense Kalmia latifolia L. understories. Two years after burning, foliar C and N pools had reached 25% and 29% of pretreatment levels, respectively. Foliar N concentrations were not different from pretreatment values. Standing wood C and N pools were 1% and 2%, respectively, of pretreatment values. Wood N concentrations were significantly higher on two sites, likely related to differences in fire intensity. Forest floor N content 2 yr after burning was 90% of pretreatment levels, most contained in unconsumed large woody material. Forest floor mass was significantly lower in the Oi layer and unchanged in the Oe + Oa layers. Forest floor N concentrations were generally lower after treatment. The site with the least intense fire and the lowest mass loss from the forest floor had the highest forest floor, foliage, and wood N concentrations 2 yr after burning. Site recovery after felling and burning was a function of fire severity and the capacity for site-nutrient retention through plant uptake.