Casuarina - Cultivation and Uses

Cultivation and Uses

Commonly known as the she-oak, sheoak, ironwood, or beefwood, casuarinas are commonly grown in tropical and subtropical areas throughout the world. The tree has delicate, slender ultimate branches and leaves that are no more than scales, making the tree look more like a wispy conifer. The plants are very tolerant of windswept locations, and are widely planted as windbreaks, although usually not in agricultural situations.

C. equisetifolia is a common tropical seashore tree known as Common Ironwood, Beefwood, Bull-oak, or Whistling-pine and is often planted as a windbreak. The wood of this tree is used for shingles, fencing, and is said to make excellent, hot burning firewood.

C. oligodon has been planted in New Guinea in an ancient (more than 3,000 years) silviculture by highland gardeners practicing an intensive traditional permaculture. The wood of this tree is used for building-timber, furniture and tools and makes excellent firewood. The tree's root nodules are known to fix nitrogen, and it is traditionally prized for its ability to increase the soil's fertility. Its abundant leaf-fall is high in nitrogen and traditionally prized for mulch.

The resin exuded from some casuarinas is edible and was a food source for Aboriginal people.

Gardeners in Bermuda can appreciate that all parts of the casuarina tree (needles, sawdust, bark, and prepared mulch) can be useful in lowering the soil pH, as Bermuda's topography consists of naturally high pH limestone rock, and perhaps only a foot of red or sandy soil. Lowering soil pH makes the soil more acidic, which can help Bermuda's biodiversity by growing acid-loving plants such as blueberries, blackberries, azaleas, rhododendrons, and such plants that may be seen in similar hardiness zones as Bermuda (USDA 9-11), such as plants found in New Zealand and Florida, which naturally have a lower pH soil than Bermuda, albeit some other environmental differences as well.