The establishment of shortleaf pine following repeated prescribed burns at Catoosa WMAThis article is part of a larger document. View the larger document here.
A mature shortleaf pine (Pinus echinata) stand on the Cumberland Plateau in Tennessee at the Catoosa Wildlife Management Area was harvested in 2001 in response to a regional southern pine beetle outbreak and converted into a savannah through periodic prescribed burns in 2005, 2010, and 2013. Following the harvest and series of burns, the stand was occupied by shortleaf pine seedlings and saplings of different sizes (<5 feet, 6 to 10 feet, and >10 feet) at a rate of approximately 400 stems per acre. Given the re-sprouting capability of shortleaf pine, the objective of this study was to assess the age of the shortleaf pine regeneration to determine if establishment occurred progressively over time in conjunction with known prescribed burn dates or during a single event prior to, during, or after the timber harvest in 2001. Shortleaf pines from each height class were aged above-ground level and below-ground level at or just above the basal crook to determine when they initiated and if and when they re-sprouted. An analysis of variance and post-ANOVA mean separation were used to determine differences amongst mean ages of each height class. Shortleaf pines from all three height classes had similar below-ground ages of approximately 13 years, indicating that they were of a single cohort initiating around the time of the 2001 timber harvest (p=0.4104). While shortleaf pines in the 6- to 10-foot height class and the >10-foot height class had similar above-ground ages of 12 and 10 years respectively, shortleaf pines currently less than five feet tall were significantly younger above-ground, averaging 6 years in age (p<0.001). Shortleaf pines currently less than five feet in height were more than likely top-killed in the 2005 prescribed burn and have since re-sprouted, while those currently greater than five feet tall were more than likely not top-killed in the 2005 burn. The fluctuations in age and growth of regenerating stems of shortleaf pine in this study are indicative of the mosaic of stand burns and their impact across the stand.