Masters Thesis completed 2011


Unks, R.R., T.H. Shear, A. Krings, and R.R. Braham. 2014.
Environmental controls of reproduction and early growth of Lindera melissifolia (Lauraceae). 
Castanea 79(4):266–277
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Ryan Unks


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=0.02, p=0.016).

We concluded hydrology should be a primary concern for future studies.