Carolina Sandhills Research Articles

Characterising dispersal and potential impacts of non‐native red swamp crayfish (Procambarus clarkii) populations in the coastal plain region of the pee Dee River basin, U.S.A.

Abstract Non‐native species can spread rapidly through aquatic ecosystems in association with both natural and anthropogenic mechanisms, but the relative importance of these two mechanisms in determining the spread of a species is not always clear. The red swamp crayfish (Procambarus clarkii) has been introduced to multiple continents, including waterbodies in the United States where both natural and anthropogenic dispersal are likely to have contributed to its current distribution. The present study combined comparisons of historical and contemporary distributions of P. clarkii and several high conservation priority crayfish species, regional field sampling, and microsatellite‐based genetic approaches from the Pee Dee River basin in North Carolina and South Carolina to understand the dispersal patterns of P. clarkii and its potential effects on native crayfishes. Field sampling and microsatellite analyses revealed widespread populations of P. clarkii throughout the study area with catchment‐specific patterns of population genetic structure, wherein more distinct genetic structures were found in the basin with historic aquaculture activities and a longer period of occurrence. The rapid spread of P. clarkii has occurred concurrently with extirpations of populations of native crayfishes, namely the Waccamaw crayfish (Procambarus braswelli), the Carolina Sandhills crayfish (Procambarus pearsei) and the coastal plain crayfish (Procambarus ancylus). The rapid spread of P. clarkii and coincident extirpation of native crayfishes calls for more extensive regulatory controls to help prevent the intentional or accidental release of non‐native crayfishes through aquaculture practices, bait releases, the pet trade and the environmental education industry.

First Report of Bacterial Leaf Spot Disease on Sesame (Sesamum indicum L.) Caused by Pseudomonas syringae pv. sesami in North Carolina.

In July 2022, dark brown to black, angular, water-soaked lesions were observed on sesame leaves (Sesamum indicum L.) in a research plot established to assess yield potential for eight varieties at the North Carolina (NC) Sandhills Research Station (Chavez 2023). Symptoms were indicative of a bacterial leaf spot (BLS). At early flowering stage, leaf spots were present on scattered plants; varieties ES108, SS3301, and ES201 exhibited up to 75% disease prevalence, with lower frequency in ES103, S39, S4302, S3251, and S3276. Symptomatic leaves from 3-4 plants were collected on four different dates from July through September. A section of symptomatic tissue was excised and macerated in sterile deionized water (SDW). A 10 µL aliquot was streaked onto SPA medium (15 g sucrose, 5.0 g proteose peptone, 0.50 g MgSO4 7H2O, 0.25 g K2HPO4, 15 g agar per liter of SDW) and incubated at 28ºC. After 72 h, numerous, smooth, white-cream colored, convex-shaped, colonies were individually isolated. Five randomly selected isolates from the different collection dates, designated as AHP108-AHP111 and AHP116, were genotyped. The 16S rRNA, gyrB, rpoD, and gapA genes were sequenced (Heuer et al. 1997; Hwang et al. 2005) and deposited to NCBI (GenBank Accessions: P213467- PP213470; OQ628040-OQ628042; PP214983-PP214994; and PP255798). These five isolates shared 100% sequence identity for gyrB and rpoD. AHP108-AHP111 shared 100% sequence identity for 16S rRNA and gapA, with 99.7% and 90.8% identity, respectively, for AHP116. A phylogenetic tree was inferred from a maximum-likelihood analysis of concatenated gyrB, rpoD, and gapA sequences of the five isolates and the top 11 hts from a blastn search of the NCBI nucleotide database. Those hits included closely related sequences from Pseudomonas syringae pv. sesami type strains ICMP 763T and ICMP 7459T. Based on this phylogenetic analysis AHP108-AHP111 and AHP116 are P. syringae pv. sesami. Recent genomic analysis suggests this pathovar is part of P. amygdali (Gomila et al. 2017), but an official name change has not been proposed. Each of the five isolates were infiltrated into leaves of sesame varieties ES108, ES103, and S327, consistently resulting in similar symptoms. Thus, strain AHP116, as a representative, was used to fulfill Koch's postulates using five, 30-day-old potted sesame plants (var. S3301). Plants were spray-inoculated with a bacterial suspension of ~108 CFU/ml until runoff; plants were incubated in moist chambers 24 h pre and post inoculation at 28ºC with 80% relative humidity and a 12 h photoperiod. At 13 days post inoculation, symptoms resembling those on plants at the Sandhills Research Stations in 2022 were evident. Reisolated bacteria were confirmed to be AHP116 through 16S rRNA and gyrB amplification and sequencing. No symptoms were observed on the five water-inoculated plants. BLS of sesame has been reported in Asia and is thought to be seedborne (Firdous et al. 2009; Prathuangwong and Yowabutra 1997). To our knowledge, this is the first report of P. syringae pv. sesami causing BLS on sesame in North Carolina. Sesame cultivation in the state increased from approximately 2,000 acres in 2022 to 13,000 acres in 2023 and there is interest in cultivating sesame as a rotational and alternative crop because it requires minimal input costs. Potential outbreaks of BLS in this warm, humid region could negatively affect sesame production, where little is known about the economic impact of the disease.

Spatial Multi-Criteria Decision Modeling for Pinus palustris Mill. (Longleaf Pine) Restoration in the South Carolina Sandhills Wiregrass Gap

Spatial Multi-Criteria Decision Modeling for Pinus palustris Mill. (Longleaf Pine) Restoration in the South Carolina Sandhills Wiregrass Gap

The Influence of Slash Management Practices on Water and Nutrient Dynamics in Longleaf Pine Forests

(1) Silvicultural applications that manipulate woody debris loading and the structural composition of a forest can have both short and long-term effects on biogeochemical cycling. Longleaf pine forests have been the historically dominant community types throughout much of the Southeastern United States. Fire exclusion, hardwood encroachment, and resource exploitation have severely reduced the amount of remaining longleaf pine habitats, making ecological restoration necessary. The silvicultural treatments used to reestablish these communities have been widespread, leading to some skepticism regarding the sustainability of certain restoration practices. (2) This study aimed to understand how overstory manipulation and woody debris management affected soil water retention rates and nutrient availability. Using a randomized complete block design, abiotic responses to biomass harvesting, conventional harvesting, and mastication treatments were measured across a soil moisture gradient in the South Carolina sandhills. (3) Our findings indicate that mastication increased soil moisture retention rates by 37% and 41%, on average, compared to conventional harvesting and biomass harvesting, respectively. (4) Additionally, soil nutrient stocks did not decline following any management practice, indicating that both biomass harvesting and mastication treatments may not necessarily impact site productivity in a negative manner. These findings imply that mastication treatments keep moisture retention high and do not immediately change soil nutrient availability in longleaf pine forests. Long-term vegetation response studies should continue to document successional trends in conjunction with moisture retention rates and long-term nutrient pulsing.

Where There’s a Will … : Rural Enslavement and National Register of Historic Places Diversity

ABSTRACT Three archaeological sites in the South Carolina Sandhills provide insight into the opportunities and challenges associated with the archaeology of rural enslavement. A consideration of the material culture and historical context of these sites raises questions about the National Register of Historic Places’ standards of significance and integrity and their applicability in historical environments of scarcity. By examining sites with quantitatively small assemblages, but large stories to tell, this article explores prospects for expanding the histories curated in the National Register of Historic Places.

Critical Material Culture Analysis in US National Register of Historic Places Significance Statements

ABSTRACT Significance statements express the values of archaeological assemblages and effect the preservation of sites in the United States. Through an evaluation of 219 significance statements from the South Carolina Sandhills, this paper explores trends in the analysis of material culture in Section 106 and Section 110 assessments. A review of archaeological guidelines from 47 states contextualizes the patterns of material culture analysis observed in the Sandhills. This research indicates an overreliance on subjective quantification measures and undefined artifact density calculations fostered by the absence of robust material culture analysis recommendations in state guidelines. A consideration of the impact bias in National Register of Historic Places recommendations suggests that modifications to state guidelines, university curricula, and historic contexts are necessary to address the systems that permit the perfunctory treatment of material culture in compliance archaeology.

Soil Chemistry and Clay Mineralogy of an Alluvial Chronosequence from the North Carolina Sandhills of the Upper Coastal Plain, USA

Temporal changes in soil development were assessed on fluvial terraces of the Little River in the upper Coastal Plain of North Carolina. We examined five profiles from each of six surfaces spanning about 100,000 years. Soil-age relationships were evaluated with inter-surface clay mineral comparisons and regression of chemical properties versus previously reported optically-stimulated luminescence ages using the most developed subsoil horizon per profile. Bases to alumina (Bases/Al2O3) ratios have negative correlations with age, whereas dithionite-Fe (FeD) concentrations are positively correlated with time and differentiate floodplain (<200 yr BP) from terrace (≥10 ± 2 ka) soils and T4 pedons (75 ± 10 ka) from younger (T1-T3b, 10 ± 2–55 ± 15 ka) and older (T5b, 94 ± 16 ka) profiles. Entisols develop into Ultisols with exponentially decreasing Bases/Al2O3 ratios, reflecting rapid weatherable mineral depletion and alumina enrichment during argillic horizon development in the first 13–21 kyr of pedogenesis. Increasing FeD represents transformation and illuviation of free Fe inherited from parent sediments. Within ~80–110 kyr, a mixed clay mineral assemblage becomes dominated by kaolinite and gibbsite. Argillic horizons form by illuviation, secondary mineral transformations, and potentially, a bioturbation-translocation mechanism, in which clays distributed within generally sandy deposits are transported to surface horizons by ants and termites and later illuviated to subsoils. T5b profiles have FeD concentrations similar to, and gibbsite abundances greater than, those of pedons on 0.6–1.6 Ma terraces along Coastal Plain rivers that also drain the Appalachian Piedmont. This is likely because the greater permeability and lower weatherable mineral contents of sandy, Coastal Plain-sourced Little River alluvium favor more rapid weathering, gibbsite formation, and Fe translocation than the finer-grained, mineralogically mixed sediments of Piedmont-draining rivers. Therefore, recognizing provenance-related textural and mineralogical distinctions is crucial for evaluating regional chronosequences.

Predation of a Cavity Kleptoparasite by an Eastern Rat Snake (Pantherophis alleghaniensis) at an Active Nest Cavity of a Red-Cockaded Woodpecker (Dryobates borealis)

I report a case of predation by Pantherophis alleghaniensis (Eastern Rat Snake) on an adult Melanerpes erythrocephalus (Red-headed Woodpecker) at an active nest cavity of a Dryobates borealis (Red-cockaded Woodpecker [RCW]) in the North Carolina Sandhills. The first RCW nest in this cavity failed during the nestling stage, either from the activities of the snake or the Red-headed Woodpecker. I believe this is the first documentation of a predation event of a kleptoparasite at an active nest cavity of a RCW by a rat snake. The resident RCWs re-nested successfully in the same cavity, illustrating the complex species interactions among rat snakes, cavity kleptoparasites, and RCWs in the Pinus palustris (Longleaf Pine) ecosystem.

The Impact of Prescribed Burning on Native Bee Communities (Hymenoptera: Apoidea: Anthophila) in Longleaf Pine Savannas in the North Carolina Sandhills.

Prescribed burning is a common silvicultural practice used in the management of longleaf pine (Pinus palustris Mill., Pinales: Pinaceae) savannas to reduce hardwood encroachment and ground cover and to maintain biodiversity. We investigated the response of the native bee community (Hymenoptera: Apoidea: Anthophila) in the Sandhills of North Carolina to prescribed burning on a 3-yr rotation over two consecutive years (2012 and 2013). We deployed bee bowl traps in sites that had been burned the year of sampling, 1 yr before, 2 yr before, and in unburned controls. In total, 2,276 bees of 109 species were captured. Bee abundance declined with time since fire, with 2.3 times more bees captured in the most recently burned sites than in unburned controls. Bee diversity also declined with time since fire, with 2.1 times more species captured in the most recently burned sites than in controls. Bee community composition also responded to fire; we present evidence that this response was mediated in part by the effect of fire on the amount of bare ground and canopy cover. Bees nesting aboveground were unaffected by fire, contrary to our expectation that fire would destroy the wood and stems in which these species nest. Our results indicate that prescribed burning is a silvicultural practice consistent with pollinator conservation in longleaf pine ecosystems of the North Carolina sandhills.

Fossil tabulate corals reveal outcrops of Paleozoic sandstones in the Atlantic Coastal Plain Province, Southeastern USA.

The geologic history of the Southeastern United States of America is missing nearly 350-million-years of rocks, sediments, and fossils. This gap defines the Fall Line nonconformity where Upper Ordovician consolidated rocks are directly overlain by Upper Cretaceous unconsolidated sediments of the Atlantic Coastal Plain Province. Here we begin to fill in the missing geologic record by reporting the discovery of fossils of lower-to-middle Paleozoic tabulate corals (Syringophyllidae) in angular, quartz-rich, ferruginous sandstones that crop out in the Carolina Sandhills Physiographic Province that forms the updip margin of the Atlantic Coastal Plain Province near the Fall Line. These fossils of extinct tabulate corals are the first evidence that Paleozoic (Upper Ordovician–Lower Silurian) sandstones crop out amidst the mostly Mesozoic-to-Cenozoic deposits of the Atlantic Coastal Plain Province of the United States of America. This discovery of Paleozoic fossils and strata in a region in which they were previously entirely unknown offers a more complete insight into the geologic history of the Southern Appalachian Mountains Region, Carolina Sandhills and updip margin of the Atlantic Coastal Plain Province and extends the previously identified range of Syringophyllidae in North America.

Impacts of urbanization on stormflow magnitudes in small catchments in the Sandhills of South Carolina, USA

Abstract Research on urban flood hydrology—especially in small watersheds—is urgently needed in response to a dearth of small catchment studies, rapid urban growth, increased flash flooding, and precipitation variability. This study compares stormflow between three small catchments in the South Carolina Sandhills of the USA: two heavily urbanized, and one forested catchment that serves as a proxy for pre-urban conditions. Comparisons of runoff volume, runoff coefficient, peak discharge, and shape of dimensionless unit hydrographs (DUH) show significantly larger stormflow volume and peak instantaneous discharge in the urban catchments that exceed those in the forested catchment by more than an order of magnitude. Changes in hydrograph shapes are visualized by DUHs and measured by skewness and kurtosis. Urban kurtosis values of DUHs are significantly higher than forested kurtosis values (p-values

How effective is the Safe Harbor program for the conservation of Red-cockaded Woodpeckers?

ABSTRACT Land use restrictions imposed by the Endangered Species Act may create conflict, affecting conservation on private lands. In 1995, the Safe Harbor program (hereafter, ‘Safe Harbor’) was initiated to alleviate concerns of private landowners about conservation of imperiled species. The inaugural program targeted endangered Red-cockaded Woodpeckers (Picoides borealis; hereafter, ‘RCW') in the North Carolina Sandhills, USA. Landowners enrolled in the Safe Harbor select management actions to enhance habitat for existing populations, but incur no additional responsibilities for increases in populations. Despite the relevance for conservation, the benefits of Safe Harbor remain largely unknown. Here, we evaluate the effects of Safe Harbor on RCWs in the North Carolina Sandhills. Between 1980 and 2014, we monitored 55 RCW territories (30 Safe Harbor, 25 control). Following the initiation of Safe Harbor, the probability of territory abandonment on control properties increased by ∼14% over a 19-yr period, ...

A novel approach for estimating densities of secretive species from road-survey and spatial-movement data

Context Accurate estimates of population density are a critical component of effective wildlife conservation and management. However, many snake species are so secretive that their density cannot be determined using traditional methods such as capture–mark–recapture. Thus, the status of most terrestrial snake populations remains completely unknown. Aim We developed a novel simulation-based technique for estimating density of secretive snakes that combined behavioural observations of snake road-crossing behaviour (crossing speed), effort-corrected road-survey data, and simulations of spatial movement patterns derived from radio-telemetry, without relying on mark–recapture. Methods We used radio-telemetry data to parameterise individual-based movement models that estimate the frequency with which individual snakes cross roads and used information on survey vehicle speed and snake crossing speed to determine the probability of detecting a snake, given that it crosses the road transect during a survey. Snake encounter frequencies during systematic road surveys were then interpreted in light of detection probabilities and simulation model results to estimate snake densities and to assess various factors likely to affect abundance estimates. We demonstrated the broad applicability of this approach through a case study of the imperiled southern hognose snake (Heterodon simus) in the North Carolina (USA) Sandhills. Key results We estimated that H. simus occurs at average densities of 0.17 ha–1 in the North Carolina Sandhills and explored the sensitivity of this estimate to assumptions and variation in model parameters. Conclusions Our novel method allowed us to generate the first abundance estimates for H. simus. We found that H. simus exists at low densities relative to congeners and other mid-sized snake species, raising concern that this species may not only have declined in geographic range, but may also occur at low densities or be declining in their strongholds, such as the North Carolina Sandhills. Implications We present a framework for estimating density of species that have traditionally been considered too secretive to study at the population level. This method will greatly enhance our ability to study and manage a wide variety of snake species and could be applied to other secretive wildlife species that are most frequently encountered during road surveys.

Trait space of rare plants in a fire-dependent ecosystem.

The causes of species rarity are of critical concern because of the high extinction risk associated with rarity. Studies examining individual rare species have limited generality, whereas trait-based approaches offer a means to identify functional causes of rarity that can be applied to communities with disparate species pools. Differences in functional traits between rare and common species may be indicative of the functional causes of species rarity and may therefore be useful in crafting species conservation strategies. However, there is a conspicuous lack of studies comparing the functional traits of rare species and co-occurring common species. We measured 18 important functional traits for 19 rare and 134 common understory plant species from North Carolina's Sandhills region and compared their trait distributions to determine whether there are significant functional differences that may explain species rarity. Flowering, fire, and tissue-chemistry traits differed significantly between rare and common, co-occurring species. Differences in specific traits suggest that fire suppression has driven rarity in this system and that changes to the timing and severity of prescribed fire may improve conservation success. Our method provides a useful tool to prioritize conservation efforts in other systems based on the likelihood that rare species are functionally capable of persisting.

Survival of Northern Bobwhite on Hunted and Nonhunted Study Areas in the North Carolina Sandhills

Radio-tagged northern bobwhite (Colinus virginianus) were monitored in the Sandhills region of North Carolina to investigate the influences of hunting on seasonal survival. We used the Kaplan-Meier product limit method with staggered entry design to calculate survival estimates and distributions for 79 radio-tagged bobwhite representing 33 coveys during November-February 1987-89. Estimated winter survival rates for year 1 (59%) and for pooled years (67%) in the nonhunted study areas were greater than in the hunted areas (31 and 45%, respectively; P < 0.05). Survival trends for the second winter were again greater in the nonhunted study areas (7 4%) but not different than hunted study areas (63%; P > 0.05). Avian predation was the major proximate cause of mortality, accounting for 66% of the known losses. Summer whistle count surveys indicated that nonhunted study areas contained more (P< 0.05) whistling bobwhite per station than hunted areas following winter hunting seasons.

The Carolina Sandhills: Quaternary eolian sand sheets and dunes along the updip margin of the Atlantic Coastal Plain province, southeastern United States

The Carolina Sandhills is a physiographic region of the Atlantic Coastal Plain province in the southeastern United States. In Chesterfield County (South Carolina), the surficial sand of this region is the Pinehurst Formation, which is interpreted as eolian sand derived from the underlying Cretaceous Middendorf Formation. This sand has yielded three clusters of optically stimulated luminescence ages: (1) 75 to 37 thousand years ago (ka), coincident with growth of the Laurentide Ice Sheet; (2) 28 to 18 ka, coincident with the last glacial maximum (LGM); and (3) 12 to 6 ka, mostly coincident with the Younger Dryas through final collapse of the Laurentide Ice Sheet. Relict dune morphologies are consistent with winds from the west or northwest, coincident with modern and inferred LGM January wind directions. Sand sheets are more common than dunes because of effects of coarse grain size (mean range: 0.35–0.59 mm) and vegetation. The coarse grain size would have required LGM wind velocities of at least 4–6 m/sec, accounting for effects of colder air temperatures on eolian sand transport. The eolian interpretation of the Carolina Sandhills is consistent with other evidence for eolian activity in the southeastern United States during the last glaciation.

Breeding Distribution and Population Persistence of Loggerhead Shrikes in a Portion of the North Carolina Sandhills

Abstract This study provides the first comparison of historical (1979–1994) and recent (2012–2013) breeding distributions of Lanius ludovicianus (Loggerhead Shrike) at a single location in southeastern North America. I conducted roadside and area searches for Loggerhead Shrikes in the spring (April—early June 2012 and late March—early May 2013) in Richmond County, NC, and small areas of 4 adjacent counties. Most of the study area is within the Sandhills, a subregion of the Coastal Plain. I documented a total of 44–45 breeding territories in 2012–2013, of which 36–38 (82–84%) were in the Sandhills, where I estimated the recent breeding density to be 3.2–3.4 pairs/100 km2. In both years, a smaller percentage of confirmed historic breeding sites were occupied in the Piedmont compared to the Sandhills portion of the study area, and the Piedmont had a much lower breeding density (0.6–0.8 pairs/100 km2). Sixteen of 22 (73%) confirmed historical breeding sites were occupied (n = 10) or retained suitable breeding...

Uktena riparia n. gen., n. sp. (Annelida, Clitellata, Lumbriculidae), a new spermatophore-producing oligochaete.

Uktena riparia n. gen., n. sp. has been collected in hyporheic habitats at several sites in North Carolina, southeastern USA. The genus is defined by unusual characters related to reproductive structures, including the formation of encapsulated spermatophores for sperm transfer and large bundles of genital chaetae, both previously unknown in the Lumbriculidae. The simultaneous occurrence of both spermatophores and spermathecae is rare in the microdrile oligochaetes. Uktena spermatophores appear more similar to those reported in leeches than to those in other microdrile oligochaete families. Possible synapomorphies associating Uktena with the genera Kincaidiana and Guestphalinus include a filiform, ringed proboscis, a forward shift of reproductive organs relative to the usual position in the family, and spermathecae in the atrial segment. The new species adds to the already diverse, endemic lumbriculid fauna of the North Carolina Sandhills ecoregion.

PINE BARRENS AND POSSUM’S RATIONS: EARLY ARCHAIC SETTLEMENT IN THE NORTH CAROLINA SANDHILLS

Competing models of Early Archaic settlement in the Southeast propose broad-scale organization conditioned by either lithic raw material availability or seasonal exploitation of biotic resources and social interaction. We offer a view from beyond the quarries and away from the river with data from the North Carolina Sandhills, a unique physiographic zone of the interior Coastal Plain. Analysis of the distribution of Early Archaic sites at Fort Bragg, including posited upland base camps, raw material use, and application of GIS least-cost path analysis, suggests intensive interriverine settlement, with watershed divides serving as conveyance corridors between high-quality toolstone areas in the Piedmont and resource blooms in the Coastal Plain. Some settlement changes are evident within the Early Archaic sequence, including a gradual shift from logistical to residential mobility and infilling of the local landscape. In the proposed Sandhills model, biocultural needs, social interaction, and requirements for high-quality toolstone are identified at the local band level. Mobility and settlement are considered to be broadly structured by networks of interriverine trails between the major resource areas of the Piedmont and Coastal Plain. Aspects of both the bandmacroband model and Uwharrie-Allendale model apply to the Early Archaic record of the Sandhills, but with closer affinities to the latter.

Foliage and Litter Chemistry, Decomposition, and Nutrient Release in Pinus taeda

Following fertilization of forest plantations, high accumulations of nutrients in the forest floor creates the need to assess rates of forest floor decomposition and nutrient release. The study site was a 25-year old experimental loblolly pine plantation in the North Carolina Sandhills Region. Soluble and insoluble N, P, carbohydrate and phenol-tannin fractions were determined in foliage and litter by extraction with trichloroacetic acid. The long-term forest floor decomposition rate and decomposition and nutrient release in an experiment simulating removal of the overstory canopy were also determined. In litter, insoluble protein-N comprised 80%–90% of total-N concentration while soluble inorganic- and organic-P comprised 50%–75% of total-P concentration explaining forest floor N accumulations. Fertilization did not increase soluble carbohydrates in litter and forest floor decomposition rates. Loblolly pine forest floor decomposing in environmental conditions simulating removal of the overstory canopy was greatly accelerated and indicated 75% mass loss and release of 80% of the N pool within one year. This could result in a loss of substantial quantities of N at harvest due to low N uptake by seedlings in the newly planted next rotation suggesting management of the forest floor at harvest is essential to conserve site N capital in these N limited systems.