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Hurricane Hugo was a category five storm in September of 1989 that significantly impacted natural areas along the Carolina coastal plain through wind damage and storm surge flooding. Francis Beidler Forest, an Audubon wildlife sanctuary in Four Holes Swamp, suffered severe damage to its forest canopy. In response to concerns that the rare spring ephemeral Trillium pusillum var. pusillum may be negatively impacted by the loss of the mixed hardwood canopy, we established permanent plots in the spring of 1990 with single leaf, triple leaf, and flowering individuals recorded by Ecology faculty and students at The Citadel. Disruption to the forest canopy would significantly alter forest floor microhabitat conditions negatively affecting T. pusillum var. pusillum population demography. There was no expected negative effect of Hurricane Hugo, and the loss of canopy cover on the population. Evidence suggests that the decrease in canopy cover and increased light was associated with increased flowering. The coefficient of variation, as a measure of cohort variability among years, increased from flowering, to triple leaf, to single leaf across the 29 years of population monitoring. There was a significant positive association between the number of named storms in the previous two and three years and the number of single leaf plants. There was no evidence that the population is decreasing, even though the number of flowering individuals has decreased. The results of this long-term demography suggest that even severe natural disturbances, like hurricanes and tropical storms, may have a positive effect on Trillium population dynamics.

American chaffseed ( Schwalbea americana L. [Scrophulariaceae]) is a federally endangered, hemiparasitic species that primarily occurs in fire-maintained pinelands in the Atlantic and Gulf coastal plains of the US. Efforts to propagate S. americana for re -introduction into the wild have been met with mixed results. Discrepancies in our understanding of host requirements, soil ecology, and growing conditions need to be resolved in order to develop a successful ex situ propagation program. We conducted a series of greenhouse experiments to address the impact that growth media, soil microbes, mycorrhizal associations, and autoparasitism may have on successful propagation of seedlings. We also tested the effectiveness of storing bareroot plants at 4°C (39 °F) relative to plants overwintering outside or being maintained in the greenhouse. We confirmed that cold-moist stratification is necessary to achieve the high germination rates needed for ex situ propagation. Soil microbes and growth media affected S. americana survivorship. We successfully grew plants in the absence of host plants by supplementing nursery media with organic hydrolized fish fertilizer. We did not observe S. americana forming mycorrhizal associations or parasitizing its own roots (no autoparasitism). Finally, we demonstrated that 1-y-old bareroot plants stored for 3 mo at 4°C exhibited survival rates that rivaled plants that overwinter outdoors or in the greenhouse.

Purvis, K.G.; Gramling, J.M., and Murren, C.J., 2015. Assessment of beach access paths on dune vegetation: Diversity, abundance, and cover. Coastal human populations are expanding and affecting plant communities, in particular dune systems. Coastal communities face risks from storm events, while coastal dune systems are heavily affected by human population and recreation pressures. Here, we evaluate the impacts of human disturbance (beach access paths) on vegetative cover and plant diversity in coastal dunes on the Isle of Palms, South Carolina. Transects were created in the foredune, middune, and backdune vegetation communities, and plots were placed 0, 1.5, 5, 10, and 20 m from a path to assess the impacts of three types of paths (public sand paths, private sand paths, and private wooden paths) at these distances on diversity, abundance, and measures of cover. Results indicate that beach access paths reduce biodiversity and density of beach dune vegetation. Sand paths contribute to greater redu...

Lindera melissifolia is a federally endangered wetland shrub endemic to the Southeastern Coastal Plain and the Lower Mississippi Alluvial Valley. Lindera melissifolia is known to occupy seasonally flooded habitats, but little work has been done to describe habitat characteristics in the Southeastern Coastal Plain region. This research uses vegetation and environmental data collected from 50 plots in North Carolina, South Carolina, and Georgia to develop a habitat classification and description for L. melissifolia in the Southeastern Coastal Plain. Cluster analysis, nonmetric multidimensional scaling, indicator species analysis, and analysis of variance were used to assign plots to four distinct isolated wetland habitat types. Swamp Tupelo Depression Pond and Successional Swamp Forest communities supported the densest and healthiest L. melissifolia populations, followed by Pond-Cypress Pond and Pocosin, and Limestone Sink Forest habitats. Habitat degradation and other forms of disturbance were fou...

Degradation of wetlands on agricultural lands contributes to the loss of local or regional vegetation diversity. The U.S. Department of Agriculture's Wetlands Reserve Program (WRP) funds the restoration of degraded wetlands on private ‘working lands’, but these WRP projects have not been studied in the Southeast United States. Wetland hydrogeomorphic type influences hydrodynamics and thus the vegetation of restored sites, but species composition may also be affected by prior land-condition and restoration methods. We examined the variation in restored wetland vegetation of 61 WRP sites (representing 52 projects) across the Southeast region. Field surveys identified the common plant species at each site, and species composition was analyzed in relation to hydrogeomorphic type and specific restoration methods that were linked to pre-restoration habitat status. At least 380 plant species were recorded across all sites. Site floristic composition generally reflected variation in wetness conditions an...

The Wetlands Reserve Program (WRP) restores converted or degraded wetlands on private working lands; however, the nature and outcomes of such efforts are undocumented in the Southeastern U.S. Identification of wetland types is needed to assess the program’s conservation benefits, because ecological functions differ with hydrogeomorphic (HGM) type. We reviewed >100 WRP projects across the Southeast Piedmont–Coastal Plain to characterize their wetland types and to evaluate whether restoration practices favored original or modified functions. The projects encompassed four HGM types and diverse pre-restoration conditions. Nearly half were converted wetlands retired from active agriculture; the remainder were either drained vegetated wetlands or forested bottomlands degraded by timber harvest. Hydrology-repair practices varied by wetland type and prior condition, with differing functional implications. Depressions and flats typically were restored, whereas low-order riparian sites and prior-agriculture floodplains were often modified to enhance water retention. Timber-harvested floodplains were restored by removing barriers to water flow and biotic connectivity. Vegetation restoration was generally passive, but tree planting was frequent on prior-agriculture sites. Field surveys suggested that most projects had positive indicators of wetland hydrology, vegetation, and faunal use. The variety of Southeastern WRP wetlands has implications for ecosystem services at local and landscape scales.

Laurel Wilt is caused by a recently identified fungal pathogen infecting plants in the Lauraceae. Laurel Wilt is transmitted by Xyleborus glabratus (Redbay Ambrosia Beetle), which was recently introduced to the southeastern United States from Asia. As the insect expands its range in the US, so too has the disease. A query of the NatureServe Explorer database was used to identify the conservation status of native plant species and recognized plant communities that may be affected by Laurel Wilt. Laurel Wilt affects at least nine plant species, and all fifteen species in the Lauraceae currently found in North America may ultimately prove to be hosts for the disease. Four of the twelve native lauraceous species had been identified as vulnerable to extirpation or extinction, prior to the introduction of Laurel Wilt. There are 55 plant communities in the US and Canada that have a member of the Lauraceae as a dominant or diagnostic species. The majority of these plant communities have been identified a...

Ecologists have long sought to understand the relationships among species diversity, community productivity and invasion by non-native species. Here, four long-term observational datasets were analyzed using repeated measures statistics to determine how plant species richness and community resource capture (i.e. productivity) influenced invasion. Multiple factors influenced the results, including the metric used to quantify invasion, interannual variation and spatial scale. Native richness was positively correlated with non-native richness, but was usually negatively correlated with non-native abundance, and these patterns were stronger at the larger spatial scale. Logistic regressions indicated that the probability of invasion was reduced both within and following years with high productivity, except at the desert grassland site where high productivity was associated with increased invasion. Our analysis suggests that while non-natives were most likely to establish in species rich communities, their success was diminished by high resource capture by the resident community.

PARTEL (Ecology 83: 2361-2366, 2002) and EWALD (Folia Geobot. 38: 357-366, 2003) suggest that the relationship between local species density and soil pH is determined by regional species pool size, which in turn reflects the relative abundance of soil types during the evolutionary history of the flora. Ewald observed that calcareous sites in Central Europe have higher species density and larger species pools than acidic sites, and argues that this is the consequence of a Pleistocene bottleneck for acidophiles. The flora of the southern Blue Ridge Mountains USA has always been associated with primarily acidic soils. We used vegetation and soil data from 3328 100 m 2 southern Blue Ridge forest plots to examine the generality of the Partel-Ewald hypothesis. The Blue Ridge flora with less than 20% of species confined to sites above pH 4.7 contrasts dramatically with that of Europe. However, regional species pool size increases with pH. Genus- and family-level pools increase with pH, suggesting an ancient origin for this pattern. Mean species density is also strongly positively correlated with soil pH. Thus, both regional species pool size and plot species density of southern Blue Ridge forests fail to conform to predictions derived from the work of Partel and Ewald. The increase in species pool with increase in pH exhibited by southern Blue Ridge forests appears to reflect broad species distributions and tolerance for high pH conditions among species that grow predominantly under acid conditions. We conclude that richness on higher pH sites is a consequence of generally more favorable conditions for plant growth and/or establishment. Ewald may be correct in asserting that the abundance of high pH specialists in Central Europe is an historical artifact, but our data contradict the assertion of Partel and Ewald that evolution of a flora in a primarily low pH environment will necessarily translate into a negative correlation between pH and species density in local vegetation.

Any fish species that appears to be readily available in the marketplace will create an impression among the public that there is a plentiful supply of that fish in the sea, but this may belie the true state of the fisheries' stock. Here we use molecular genetic analysis to show that some three-quarters of the fish sold in the United States as 'red snapper'--the US Food and Drug Administration's legally designated common name for Lutjanus campechanus--belong to another species. Mislabelling to this extent not only defrauds consumers but could also adversely affect estimates of stock size if it influences the reporting of catch data that are used in fisheries management.

Any fish species that appears to be readily available in the marketplace will create an impression among the public that there is a plentiful supply of that fish in the sea, but this may belie the true state of the fisheries' stock. Here we use molecular genetic analysis to show that some three-quarters of the fish sold in the United States as 'red snapper'--the US Food and Drug Administration's legally designated common name for Lutjanus campechanus--belong to another species. Mislabelling to this extent not only defrauds consumers but could also adversely affect estimates of stock size if it influences the reporting of catch data that are used in fisheries management.