Distribution of pond apple (Annona glabra L) in South Florida

Pond apple (Annona glabra; Annonaceae) is a small tree native to wetlands of the neotropics.  In Australia and some Pacific islands, pond apples are an invasive exotic, threatening ecosystem stability. Historically, South Florida hosted large, dense monotypic stands of pond apple.  Due to intensive human disturbance in the Everglades ecosystem, these large stands no longer exist.   Understanding the habitat preferences of pond apple, including ecological factors that lead to dense stands in its native habitat, may aid restoration efforts and prevent the further spread of pond apple in regions where it is invasive.  We collected data on the density and distribution of pond apple in relation to habitat characteristics in 13 sites within the Florida peninsula, south of Lake Okeechobee.  Habitat characteristics quantified included canopy cover, soil/water pH, percent leaf damage and habitat type. In contrast to pond apple populations in Australia and what was historically reported in Florida, we found no dense, mono typic stands of adult trees.  Habitat characteristics that were significantly related to pond apple density and distribution include soil pH, habitat type and canopy cover.  Specifically, pond apples were denser and less clumped in hardwood swamps and more clumped in areas with high pH.  We discuss the implications of these results for conservation and further research.