Tuesday, August 5, 2008 - 10:30 AM

COS 24-8: Landscape changes on the Apalachicola National Forest, a fire dependent ecosystem

Charels A. Hess and Antoine Laniray. Florida State University

Background/Question/Methods

Historical practices and a focus on uplands have led many land managers to believe that 3-5 year fire return intervals are enough to maintain the longleaf pine ecosystem.  On the Apalachicola National Forest (ANF), the current fire regime has allowed many fire dependent species to persist and this forest is considered one of the best burned parcels in the National Forest system. However, the fire return frequencies in the ANF have failed to maintain the characteristic wet flats which are transition zones between the coniferous uplands and deciduous bottomlands.   I analyzed aerial photographs taken over a span of 70 years for 50 randomly selected sites and used GIS technology to estimate the amount of encroachment of titi (Cyrilla racemiflora and Cliftonia monophylla) into the transition zones and wet flats. 

Results/Conclusions   In that period an estimated 14% of the landscape has been lost to titi encroachment.  This loss amounts to approximately 80,000 acres of the wet prairie/ longleaf system being lost. When areas with greater than 5 year fire return intervals were compared to those with 3-5 year intervals, no significant differences were observed.  Only one compartment in the sample showed evidence of maintaining the wet flats of the Apalachicola and it had a fire return interval of less than 3 years. These results suggest that fire return intervals of more than three years, at least with non-growing season burns, are not adequate to maintain the edges of the longleaf pine ecosystem.