The Australian pine is native to Malaysia, south Asia, Oceania and Australia. Brought to Florida in the late 1800s for ditch and canal stabilization, shade and lumber. The scientific name is Casuariana equisetiifolia. A deciduous tree with soft, wispy pine-like appearance that grows to 100 feet or more in height. It is also known as ironwood, beefwood, she oak, and horsetail tree. There is a superficial resemblance to the conifer genus Pinus due to its small, round, cone-licoastalits and its branchlets of scale-like leaves that look like pine needles. The Australian pine is capable of flowering year-round, producing tremendous numbers of small, winged seeds which are dispersed by the wind.
The Australian pine is established in the Hawaiian Islands, costal Florida, Puerto Rico, the Bahamas and many other Caribbean islands. You will find it in open coastal strand habitat with sand and shell beaches, rocky coasts, sand dunes and sand bars in subtropical climates.
An Australian pine can group five to ten feet per year and produce a dense shade and think blanket of leaves and hard pointed fruit that completely cover the ground beneath. Native dune and beach vegetation, including mangroves and other resident beach adapted species have been displaced due to dense thickets of Australian pines. Through microbial association, the roots are capable of producing nitrogen and can colonize nutrient-poor soils. Once the trees are established, they radically alter the light, temperature and soil chemistry regimes of beach habitats. The ground below then becomes ecologically sterile and lacking in food value for native wildlife. Due to their thick shallow roots, they are much more susceptible to blow-over during high wind events. In turn, this leads to increased beach and dune erosion and infers with the nesting activities of sea turtles.
Since there are no biological controls currently available for management of the Australian pine, raking, and removal of the leaf litter, cones and seeds should be done whenever possible. Small or new infestations of pine seedling or saplings should be removed manually. For a heavier infestation, an application of the systemic type of herbicide to the bark cut stumps or foliage is the most effective. A fire has also been prescribed for use in large infestations in fire-tolerant communities.