Some of the most species-rich areas and highest concentrations of threatened and endangered species in the southeastern United States are found in wet savanna and flatwood longleaf pine (Pinus palustris Mill.) communities. Where intensive forestry practices have eliminated much of the natural understory of the longleaf ecosystem, the potential for reestablishment through a seed bank may present a valuable restoration opportunity. Longleaf pine sites converted to loblolly pine plantations and non-disturbed longleaf sites on the Coastal Plain of North Carolina were examined for seed bank presence and diversity. Conducting vegetation surveys and examining the seed bank using the seedling emergence technique allowed for verification of the seed bank presence, as well as evaluation of the quality of the seed bank on disturbed longleaf pine sites. Forty-three species and over 1,000 individuals germinated, and the seed banks of both the disturbed and non-disturbed stand types contained species not noted in the vegetation survey. Although many of these species were considered weedy and typical of disturbance, numerous taxa were indicative of stable longleaf pine communities. This study confirms both the presence and quality of seed banks in highly disturbed former longleaf pine sites, suggesting that the seed bank may be an important tool in restoration efforts.
Lindera melissifolia is a federally endangered endemic shrub of the southeastern United States. Numerous populations are gender-biased. The goal of this study was to determine environmental conditions most appropriate for establishment and growth of seedlings and adult females. Seedlings were grown under varied moisture and light to compare growth rates and morphological ratios. Seedlings were clipped to simulate two levels of disturbance, and their shoot sprouting ability was assessed. Densities of adult flowering stems, co-occurring species, and solar transmittance were analyzed within two North Carolina populations. The lowest levels of light resulted in decreased growth, but light and moisture did not interact to affect seedling growth rate significantly. Morphological ratios and growth responses followed patterns expected for plants exhibiting plasticity in response to varied light levels, but not to moisture. Clipping immature plants below root collars decreased survivorship to 31%. Growth rates of new shoots when clipped below and above the root collar were 40% and 58% percent lower, respectively (p < 0.001). Percent cover of Lindera melissifolia explained 52% of the variation in the number of male flowering stems per plot and 14% of the variation in female stems per plot. No relation of stem density to percent transmittance was found. Indicator species analysis revealed association of males with facultative wetland species and a weak association of females with wetland obligates, but overall difference in vegetation composition between plots with or without females present was slight (MRPP: A ¼ 0.02, p ¼ 0.016). We concluded hydrology should be a primary concern for future studies.
Ap p r o v e d b y :Co r o lla Wild Ho r se Fu n d Da t e Co u n t y o f Cu r r it u ck Da t e NC Na t io n a l Est u a r in e Re se a r ch Re se r v e , Da t e De p a r t m e n t o f En v ir o n m e n t a n d Na t u r a l Re so u r ce s Cu r r it u ck Na t io n a l Wild life Re fu ge , Da t e U.S. Fish a n d Wild life Se r v ice , De p a r t m e n t o f In t e r io r
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