Ichauway

The Ichauway Forest Dynamics Plot was established between March 2022 and February 2023 at the Jones Center at Ichauway in Newton, GA. The 15.21 ha plot (390 × 390 m) is a second-growth mixed pine-oak longleaf pine woodland. These woodlands are located within a global biodiversity hotspot where structure, function, and diversity are maintained through a unique suite of environmental controls, including frequent disturbance from fire and tropical cyclones. While the stand is dominated by an overstory of longleaf pine (Pinus palustris), it contains a variety of xeric-adapted oaks (e.g., Quercus margaretta and Q. incana), and mesic oaks (Q. virginiana and Q. hemisphaerica).  Compositional attributes suggest long-term recurrent but inconsistent use of fire, including a diverse understory comprised of >150 herbaceous species, a midstory of oaks and other hardwoods, and the occurrence of many disturbance-sensitive perennial species such as Asclepias spp. and Aristida spp. The site has been managed with prescribed fire since at least the 1920s and with prescribed burns every 2 years since at least the 1990s. Currently, the site receives a spring burn on odd years, most recently in March 2023.

The site is representative of many remaining longleaf woodlands throughout the southeastern coastal plain, which have a shared history of degradation through logging and often fire exclusion. In the initial 2022 survey, the plot contained 18,295 stems > 1cm diameter at breast height from 26 species. The dominant species include P. palustris (59.5% by basal area), Q. margaretta (18.1%), and Q. hemisphaerica (7.6%), and Q. incana (6.0%). The overstory pines at the site were primarily established ~1920s, likely after overstory harvest. The average establishment date for longleaf pine in the plot is 1969, with the oldest pines dating to the late 1800s. There were pulses of longleaf pine establishment from 1915-1925 and 1950-1960, although the majority have established in the period from 1980 to present day. The majority of oaks were established between 1985-1995. A few of the oldest oaks, which are all Q. margaretta, were established in the 1910s.  

The Ichauway Forest Dynamics Plot is useful for a broad range of ecological inquiry as it contributes to the broader network as only one of two sites in the southeastern U.S. and is located within a global biodiversity hotspot of high conservation value. The primary motivation for establishing this plot is to explore fire-scale questions about longleaf pine ecosystem dynamics including tree competition, fire ecology, and microclimate variability in ways that inform fire management and restoration in the region. In initial efforts we are (1) reconstructing the stand history using dendroecological techniques, (2) studying patterns of pine–oak competition and facilitation using geostatistical methods, and (3) understanding fire behavior and effects using remote sensing and mortality surveys. To provide data to advance the adoption of remote sensing technologies in forest ecology and restoration, in addition to census every 4 years, we aim to collect terrestrial LiDAR scans at least every 2 years (on even years) throughout the plot. We also obtain occasional LiDAR scans for other studies: current scans include October 2021, February 2023, and March 2023.

Situated within a large and active research station, the study area offers several synergistic opportunities for ecological research well beyond the primary questions being addressed. First, prescribed burns are planned collaboratively by Jones Center and conservation and research staff, so reasonable accommodations of timing, modification of burns is possible, and instrumentation can be operated during critical periods to facilitate fire research. Second, the larger research station is part of the National Science Foundation NEON network providing programmatic cross-linkages and complementary data. The area receives aerial surveys that include lidar and hyperspectral imagery (NEON AOP) approximately annually. Third, the site contains an approximately centrally located eddy-covariance tower that is part of the Ameriflux network that can facilitate studies linking forest structure and composition to ecosystem processes. For collaborators interested in extensive field studies, the Jones Center offers lodging and accommodation if available.