An assessment of annularity in Sand live oak (Quercus virginiana) and Turkey oak (Quercus laevis) in central Florida
The Tiger Creek Preserve in central Florida has one of the highest concentrations of threatened and endangered plants and animals in the United States. Historically it was probably a longleaf pine savanna, but fire exclusion in recent decades has almost certainly led to increased basal area by mid-story oaks (mainly Quercus geminata and Q. laevis). Determining the date of establishment of these trees, as well as the early fire history of the site, would provide evidence to support appropriate management of this ecosystem as well as insights into how quickly these sites degrade in the absence of fire. Here we evaluate the annularity of these oaks from cross sections of Q. virginiana and Q. laevis collected from the Preserve using dendrochronological techniques. Cross sections from both species were scanned at high resolution and ring widths were cross-dated and measured by two groups working independently. Preliminary results suggest that Q. laevis produces annual rings reliably, and that the independent groups came to nearly identical results. Rings are present in Q. virginiana, but they are often difficult to discern and the annularity in this evergreen species growing at Tiger Creek is not yet clear. Fire scars are present in both species in the early portion of their growth, but not in recent decades. Growth climate analysis of Q. laevis will be undertaken.