Growth of Eastern White Pine (Pinus strobus L.) Related to Forest Floor Consumption by Prescribed Fire in the Southern Appalachians

Chainsaw fe l l ing , burning, and p lant ing of eastern whi te pine (Pinus s t robus L.) have been prescribed on degradedpinelhardwoodstands in the Southern Appalachians to improve overstory composi t ion and product iv i ty . The desired future condi t ion the overstory is a product ive pinelhardwood mixture, wi th white pine, which is resistant to southern pine beetle (Dendroctonus frontalis), as the dominant pine. We evaluated the growth of white pine planted af ter fe l l -and-burn treatments through eight growing seasons af ter plant ing on three s i tes that di f fered in their jre characteris t ics and carbon and ni trogen losses . The three s i tes (JE, JW, and DD) dif fered in heat penetration andforestfloor consumption. Al though very l i t t le consumption of the Oe+Oa humus layer occurred during burning, consumption of the Oi l i t ter layer was 94%, 9470, and 63% at JE, JW, and DD, respectively. Corresponding to the forest floor layer consumption (Oi and Oe+Oa combined), 46% offorestfloor N was lost at JE, 45% offkestfloor N was lost at JW, and less than 0.1% of theforestjIoorNwas 1ostatDD. Biomassanddensi ty ofwoody competi tor species werenotsignijkantlyrelated to whi te pine s ize or growth. By the e ighth growing season, no di f ferences in whi te pine s ize or growth were detected between JE and JW, but DD had signif icantly smaller white pine trees. The size di f ference between DD and the other two sites was attributed to the replanting of seedlings at DD in 1992. However, relative growth rate (RGR) was significantly higher on DD in 1998 than the other two sites. Eight growing seasons after planting, white pine growth was negatively related to percent Oi layer consumed on the JE and JW si tes . We alsofoundsigni jkant re lat ionships between whi te pine RGR andpercent Oi consumed using datafrom al l three si tes . Al though f ire severi ty had a long-term ef fect on pine growth, f ire severi ty was considered low overal l on these si tes because there were l imited lossesfiom theforestfloor Oe+Oa layer. However, white pine increment and RGR were signljicantly related to percentforestfloor Oi mass and N loss . This loss of site N capi ta l could have a significant negative effect on growth of planted white pine over the long term. South. J. Appl. For. 26(1):18-2.5.