Comparison of pyric properties in southeastern Quercus spp litter: Insight into fire management and restoration

Restoration efforts in southeastern coastal plain longleaf pine forests typically focus on promoting the dominance of pine species through the reduction of hardwood trees and shrub species.  Often targeted are the many oak species (Quercus) present within these forests, in which managers typically desire to reduce the density and stature of these species.  However, the relative importance and contribution of oak species to this system are not well understood.  The physical traits and pyric properties of plants can often help evaluate the relative importance of fire, reveal potential adaptive traits and inform mangers about potential fire behavior.  In other studies, burning characteristics and have shown significant comparisons between species and the habitat/fire regimes they inhabit.  While studies have evaluated the burning characteristics of Pinus spp., analogous studies using oak species have not been conducted.  To make comparisons between the burning characteristics of southeastern Quercus spp. (n= 8), oak litter samples (n=7) were collected and burned under controlled conditions in a combustion chamber.  Each burn consisted of 15g of litter situated atop a 35cm x 35cm grid of xylene soaked cotton strings.  Burning characteristics measured consisted of maximum flame height (cm), flaming duration, smoldering duration, mass loss and mass loss rate.  To detect differences between species an ANCOVA was completed with fuelbed height as a covariate and resulted in the detection of a significant species effect for all burning characteristics measured (P > 0.01).  Rank total comparisons placed Q. stellata and Q. laevis with characteristics the most favorable to burning while Q. virginiana and Q. hemisphaerica seemingly contained relatively less favorable characteristics to burning.  These results suggest that oaks, similar to pines, have litter properties that may reflect the historical fire regime or habitat they have developed in, thus potentially revealing insight into their relative importance within longleaf pine forests.