Prescribed Fire Effects on Tree Grades and Wounds on the Monongahela National Forest, WV

Species traits, including but not exclusive to bark thickness and texture, sprouting ability, and litter bulk density and chemistry, may be related to a stem's potential to withstand potential heating from wildland fire. Trees exhibiting similarities for these properties and others may be classified into two broad functional groups: pyrophytes and pyrophobes. To our knowledge, few research studies have been conducted to determine how prescribed fires may affect wood quality of merchantable tree species in the Appalachian Mountains. Understanding potential relationships between wounding and fire tolerance may assist prescribed fire managers as they seek to promote and expand the use of prescribed fire for management purposes. To investigate this issue, six locations on the Monongahela National Forest, West Virginia, that had been subjected to one or two mixed intensity and severity prescribed fires since 2012 were selected for stand inventory in 2021. Overstory trees within these burned locations and adjacent, unburned locations were measured and graded using variable radius sampling, and additional landscape features and physiographic factors, such as aspect, elevation, and slope percentage, were also recorded at each variable radius sampling location. The most common, commercially valuable deciduous species encountered were red maple (Acer rubrum) (17.5%), white oak (Quercus alba) (9.8%), chestnut oak (Quercus montana) (32.8%), and northern red oak (Quercus rubra) (39.9%). Using field measurements and tree grades, the total number and types of wounds, potential volume loss, charring, basal area, and diameters at breast height (DBH) were compared by species, burn status (burn or control), and the number of burns. Overall, A. rubrum and Q. rubra comprised 93% of the total trees exhibiting volume loss from wounds in the burned locations. However, total volume loss only constituted about 3% of the bottommost 4.9 m log. Trees in the burned locations experiencing volume loss differed significantly between species (p=0.0294) with Q. rubra constituting 60% of volume loss trees. In burned and control plots, A. rubrum was the most commonly wounded tree with 43.5% of trees having at least one wound. Cat face and oval wounds were the only wound types resulting in volume loss. Felling and milling stems identified in this study as having potential volume loss from any fire-influenced wounds would be valuable. Furthermore, assessing the potential impact of outer bark char resulting from prescribed fires would be desired to better understand if charring constitutes any potential internal damage to stems. Deploying a similar, field-scale experiment on areas with varying fire frequencies and intensities would be useful to determine how wood quality may be affected after several prescribed burns.