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Bank, NC. In Evans’s studies, no seedlings survived after two years. Clearly longer-term studies
are needed to determine seedling success in the field.

Evidence for clonal expansion exists in the foredune, although the scale is diminished
from Evans’s (1992) assumptions of clonal expansion. Due to the limited number of foredune
samples, results could be skewed and not representative of all barrier island dune habitats beyond
Fort Fisher, NC. Little to no expansion was seen in more favorable dune habitats, with dune,
shellhash, backdune, and swale all displaying shorter main ramets and fewer, shorter lateral
ramets. The lengths, number of lateral ramets, and shorter internode distance may support more
sexual recombination occurring in these habitats. As the need for water and nutrient translocation
diminishes with distance from the shore, asexual reproduction through expansion may not be
necessary outside of the foredune. To truly know the extent of sexual reproduction, genetic
testing and analyses across gradients would more definitively answer the question of clonal
versus sexual reproduction. Greenhouse studies could also provide insight on H. bonariensis
germination requirements and seed viability.

The relative importance of Hydrocotyle bonariensis in the dune environment may be
greater than previously supposed. With a frequency of 0.06 leaves to cm in the foredune,
calculating the percent presence of this plant would be misleading using only visible leaves. In
the harsher habitats approaching the shoreline, there are more underground structures than above
ground. Hydrocotyle bonariensis may help to stabilize both the foredune and dune habitats for
other species. More research is needed to address the interactions between H. bonariensis and
other dune botanical species, but H. bonariensis may be a favorable addition to U. paniculata for
dune building protocols.

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