Lantana camara is an invasive plant species that has spread quickly across South Africa. This bird-dispersed plant suppresses surrounding plants through allelopathy. I examined the dispersal of L. camara under and away from tree canopies in a highly populated communal area and an adjacent conserved area with low human density. I hypothesized that L. camara would be more common in the communal area because of the higher grazing pressure than in the conserved area. Additionally, I hypothesized that this allelopathic plant would inhibit or retard the germination rate of two plant species. The dispersal hypothesis was examined by surveying subcanopy and intercanopy environments near Acornhoek, South Africa. The number and diameter of L. camara stems were recorded, as well as the presence of adjacent L. camara plants. The allelopathy hypothesis was examined by germinating radish Raphanus sativus and Bermuda grass Cynodon dactylon seeds in soil collected from under L. camara bushes and in open areas. We recorded germination over a span of five days. L. camara was most common in the conserved area in the subcanopy and in the communal area in intercanopy environment. We found that R. sativus seeds had a higher average germination rate in open-area soils (95%) than in L. camara soils (84%), while the opposite was true for C. dactylon seeds (84% vs. 90%). These results suggest that birds are important dispersers of L. camara seeds and that allelopathic effects vary between plant species.
Lantana camara is a bird-dispersed invasive plant with allelopathic properties. I examined the dispersal of L. camara under and away from trees in a communal area and in a conserved area. I hypothesized that L. camara would be more common in communal areas than in conserved areas. L. camara should inhibit the germination rate of radish and grass seeds. I surveyed subcanopies and intercanopies near Acornhoek, South Africa and germinated the seeds in soil from under L. camara bushes and open areas. L. camara was most common in the conserved area in the subcanopy and in intercanopies in the communal area. Radishes had a higher average germination rate in open-area soils than in L. camara soils, while the opposite was true for grass seeds.