Age, composition, and stand structure of old-growth oak sites in the Florida high pine landscape: Implications for ecosystem management and restoration

We sampled tree age, species composition, and stand structure of four high pine sites composed of old-growth sand post oak (Q, margaretta Ashe), old-g rowth turkey oak (Quercus laevis Walt.), and young longleaf pine (Pinus pal ustris Mill.) in north and central peninsular Florida. The oldest turkey oa k sampled was 123 years old, and the oldest sand post oak was 230 years old . Turkey oak exhibited the greatest diameter variation in relation to age. The median number of rings found in rotten and/or hollow turkey oaks was 63 and the corresponding number for sand post oak was 105. Age reconstruction indicated that in 1900 minimum oak tree (greater than or equal to 5 cm dia meter at breast height) density ranged from 10 to 60 trees ha(-1) among sit es. This study demonstrates that sandhill oak trees historically were an in tegral component of at least some phases of the high pine ecosystem. These data support the hypothesis that spatial patchiness and variability in fire frequency, season, and intensity historically permitted oaks to reach and maintain tree size in varying densities over time and across the high pine landscape.