- A Carolina Bay in the Land of the Longleaf Pine
Unbeknownst to the majority of North Carolina beachgoers, just a few miles away lies a different kind of bay, a Pleistocene Era landform unique to the coastal southeastern United States. Carolina bays were once lakeshores. While their elevational relief is unassuming (~ 1 to 1.5 meters), they are home to a rich and unique anthropogenic, ecological, and climatological history that is worth exploring.
Human presence on Carolina bays in North Carolina dates to the Paleoindian and Archaic periods (Brooks et al. 2015). Artifacts gathered at these sites reveal a history of hunting, ritual life, and temporary habitation (Gillam 2015). When Europeans forcibly settled North America, the longleaf pine trees depicted in this issue's cover photo occupied approximately 36.5 million hectares of the southeastern United States and were not exclusive to Carolina bays (Frost 2006). However, longleaf pine ecosystems became the site of the extractive turpentine industry. Raw sap was collected from longleaf pine trees by cutting notches at the base of the tree, removing its bark, and slashing the tree to force its resin to run. This raw resin was distilled to create turpentine. In the 19th century, turpentine was the South's third largest export with North Carolina accounting for approximately 97 percent of the national market (Outland 1996). Continued slashing, along with logging and modern fire suppression techniques have been responsible for a 97 percent decline in native longleaf pine ecosystems (Frost 2006).
While many Carolina bay longleaf woodlands were affected by the turpentine and logging industries, others were spared due to inaccessibility. What remains at such sites are relic ecosystems teeming with biodiversity and mature longleaf pine trees. Redcockaded woodpeckers (RCW), a keystone species for longleaf pine ecosystems, are currently listed as an endangered species. RCW nest in hollowed cavities of mature longleaf pines that have historically been found on remote and minimally disturbed Carolina bays (Jose et al. 2007). Trees are marked with a white painted band (as seen on some trees in the cover photo) to indicate the presence of RCW cavities. Venus flytraps, the iconic carnivorous plant species, are endemic to Carolina bay ecosystems and are also currently threatened due to loss of habitat (Luken 2005). In addition, it is estimated that one third of rare flora species in the Southeast can be found in Carolina bays, longleaf pine savannas, and karst ponds (Sharitz 2003). The estimated 10,000 to 20,000 Carolina bays and surrounding pocosin wetlands are integral to the flora and fauna composition of the southeastern United States (Richardson and Gibbons 1993). [End Page 1]
Carolina bays have been of interest for recent dendrochronology research that investigates tropical cyclone precipitation (TCP) recorded in the annual rings of longleaf pine trees (Knapp et al. 2016, Montpellier et al. 2019). Accessing Carolina bays with extant old-growth longleaf pines that were not logged or turpentined during the late 19th and early 20th centuries offers the opportunity to survey the 300-year old climatological record stored in their annual rings. Flat tops, flagging branches, gnarled trunks and RCW cavities, some of which can be seen in the issue's cover photo, are all visual indicators of mature longleaf (Harper et al. 1997). The leading hypothesis as to why longleaf pine are sensitive to TCP relates to root structure and water table height fluctuation. When TCP collects in the pocosin wetlands, the water table rises, and longleaf pine roots record this surplus water in their annual rings. This information can be used to assess how TCP has fluctuated over time (Knapp et al. 2016) and allows for the investigation of microelevational influences on tree growth and climate response (Montpellier et al. 2019).
Carolina bays are not only a landscape that is unique to the southeastern United States, but they also serve as recorders of anthropogenic and climatological history and provide refuge for species on the brink of extinction. Their research and preservation are vital as historically significant, ecologically vital, and climatologically intriguing locations in the United States are becoming increasingly rare.