Terrestrial vegetation monitoring at Chattahoochee River National Recreation Area: 2021 data summary
Authors: Boyle M. 
Published: April 2024

The Southeast Coast Network (SECN) conducts long-term terrestrial vegetation monitoring as part of the NPS Inventory and Monitoring Program. The vegetation community vital sign is one of the primary-tier resources identi?ed by SECN park managers, and monitoring is conducted at 15 network parks (DeVivo et al. 2008). Monitoring plants and their associated communities over time allows for targeted understanding of ecosystems within the SECN geography, which provides managers information about the degree of change within their parks? natural vegetation.

2021 marked the ?rst year of conducting this monitoring e?ort at Chattahoochee River National Recreation Area (CHAT). Thirty vegetation plots were established throughout the park from June through July. Data collected in each plot included species richness across multiple spatial scales, species-speci?c cover and constancy, species-speci?c woody stem seedling/sapling counts and adult tree (greater than 10 centimeters [3.9 inches {in}]) diameter at breast height (DBH), overall tree health, landform, soil, observed disturbance, and woody biomass (i.e., fuel load) estimates.

This report summarizes the baseline (year 1) terrestrial vegetation data collected at Chattahoochee River National Recreation Area in 2021. Data were strati?ed across two dominant broadly de?ned habitats within the park, including Piedmont Upland Forests and Piedmont Alluvial Wetland Vegetation and three land parcels: North?from Bowman?s Island to Abbotts Bridge, Middle?from Medlock Bridge to Gold Branch, and South?from Sope Creek to Palisades. Noteworthy ?ndings include:

299 vascular plant taxa were observed across 30 vegetation plots, including 29 species not previously documented within the park.

The most frequently encountered species in each broadly de?ned habitat included:

Piedmont Alluvial Wetland Vegetation: Chinese privet (Ligustrum sinense), sweetgum (Liquidambar styraciflua), eastern poison ivy (Toxicodendron radicans var. radicans), muscadine (Muscadinia rotundifolia var. rotundifolia), and smallspike false nettle (Boehmeria cylindrica).

Piedmont Upland Forests: tuliptree (Liriodendron tulipifera var. tulipifera), eastern poison ivy, Virginia creeper (Parthenocissus quinquefolia), cat greenbrier (Smilax glauca), muscadine, mockernut hickory (Carya tomentosa), and black edge sedge (Carex nigromarginta).

Sixteen non-native species categorized as invasive by the Georgia Exotic Pest Plant Council (GA-EPPC 2023) were encountered during this monitoring e?ort, including two not previously detected within the park?miniature beefsteak plant (Mosla dianthera) and Chinese holly (Ilex cornuta). Chinese privet and Japanese honeysuckle (Lonicera japonica) were the most frequently encountered and abundant invasive plant within the park.

One species of special concern listed for Georgia (GADNR 2024) was observed during this monitoring e?ort?large-fruited sanicle (Sanicula trifoliata).

Tuliptree, loblolly pine (Pinus taeda), boxelder (Acer negundo var. negundo), river birch (Betula nigra), and sweetgum were the most dominant species within the tree stratum of Piedmont Alluvial Wetlands of Chattahoochee River National Recreation Area; white oak (Quercus alba), loblolly pine, tuliptree, and mockernut hickory were the most dominant species of Piedmont Upland Forests.

Chinese privet was the most abundant species within the sapling and seedling strata of Piedmont Alluvial Wetlands.

The mortality rate of green ash (Fraxinus pennsylvanica) within Piedmont Alluvial Wetland plots was high, and it is likely these trees succumbed to impacts from emerald ash borer (Agrilus planipennis). The emerald ash borer
is a wood-boring pest of ash (Fraxinus sp.) and is native to Asia. Since its discovery in the U. S. in the early 2000s, the insect has been responsible for the death of tens of millions of ash trees in the eastern and midwestern parts of the country. At this time, it is not certain whether
the declining health of ash within Chattahoochee River National Recreation Area is due to emerald ash borer, edaphic factors that are responsible for natural mortality and decline, or other factors.

Other threats to native vegetation within the park are: (1) the high prevalence of non-native, invasive plant species;
(2) ?re suppression within oak-hickory; and (3) impacts from heavy browse by white-tailed deer (Odocoileus virginianus).

All plots monitored during this sampling e?ort are scheduled to be resampled in 2024.