Pandanus

The Pandanus, or Coastal Screw Pine, Pandanus tectorius, is an interesting coastal dune plant, it is sand and salt tolerant, with both male and female trees. The male flowers resemble 15-20cm corncob while the female plant forms the familiar pineapple shaped fruit, which is about 25cm across and are on the tree for 12 months. Growing to about 8m the Pandanus has stout prop roots that grow from the stem, a scarred trunk and branches results from the loss of leaves, with the leaves growing to about 1.5m long and 5-7cm wide, with prickly edges and midrib. The leaves are spiralled and crowded towards the branch ends.

Over the last few years, these trees have become vulnerable due to attack by the insect Jamella australiae. Native to north Queensland, the insect may have been introduced in nursery grown pandanus from that part of the state. The insect causes waterlogging and fungal infestation in the leaves, causing about 18% - 37% death amongst the pandanus from Northern Queensland to Port Macquarie. Two species of Aphanomerus wasps from north Queensland, natural predators of the Jamella australiae have been released as a biological control and are being closely monitored.