Prescribed fire effects on understory woody plants and fuels in <i>Quercus-Pinus</i> mixedwoods

Abstract

To enhance forest resilience to predicted increases in forest stressors, managers increasingly desire ecologically-based restoration approaches that increase ecosystem adaptation potential. Mixedwood stands, which contain a range of life history and functional traits, may be more resistant and resilient to ecosystem stressors. Management of <i>Quercus-Pinus</i> mixedwood stands includes the use of prescribed fire, which requires an understanding of vegetation-fuels-fire feedbacks in these ecosystems. However, a paucity of knowledge exists on the intra-stand spatial patterns of fire effects. We analyzed the effects of a newly initiated prescribed fire program on the intra-stand characteristics of understory woody plants and fuelbed composition and loading in a long-unburned <i>Quercus-Pinus</i> mixedwood stand in Tennessee, USA. We sampled vegetation and fuels in two plots, one that experienced two prescribed fires (burned plot), and one fire-excluded plot directly adjacent (unburned plot). On the burned plot, we recorded lower sapling and seedling densities across taxa. Spatial analysis of advance reproduction in the burned plot indicated a combination of patchy fire effects, canopy openings, and high-light understory environments. We documented significant reductions in total fuel mass. The combination of spatial analysis and ordination revealed that prescribed fires homogenized fuel loads within the burned plot.