The Norfolk Island Pine or Norfolk Pine Araucaria heterophylla (synonym A. excelsa) is a distinctive conifer, a member of the ancient and now disjointly distributed family Araucariaceae. As its name implies, the tree is endemic to Norfolk Island. The trees grow to a height of 50-65 m, with straight vertical trunks and symmetrical branches, even in the face of incessant onshore winds that can contort most other species. The leaves are awl-shaped, 1-1.5 cm long, about 1 mm thick at the base on young trees, and incurved, 5-10 mm long and variably 2-4 mm broad on older trees, the thickest, scale-like leaves on coning branches in the upper crown. The cones are squat globose, 10-12 cm long and 12-14 cm diameter, and take about 18 months to mature. They disintegrate at maturity to release the nut-like edible seeds.

The scientific name heterophylla ("different leaves") derives from the variation in the leaves.

Cultivation and uses

Its distinctive appearance, with widely spaced branches and a symmetrical, triangular outline, has made it a popular cultivated species, either as a single tree or in avenues. It is particularly widely planted in Australia, New Zealand, Florida, Hawaii and southern California.

Norfolk Island Pines grow well in deep sand, as long as they receive reliable water when young. This, and their tolerance for salt and wind, make them ideal for coastal situations.

Post-hurricane damage to a Norfolk Island Pine

In Florida, these trees are subject to freeze damage and as a result produce multiple stems with weakly attached trunks. In the 2004 hurricane season, many of these trees failed under the 160 km/h winds. Some coastal communities (e.g. Vero Beach) prohibit their use as a tree in local landscape plan approvals.

Young trees are often grown as houseplants in areas where the winters are too hard for them to grow outside (they will not, for example, survive outdoors in most of the United States or Europe, but are sometimes used as Christmas trees there, as elsewhere). The timber is good for woodturning, and is extensively used by Hawaiian craftspeople. However, British explorer James Cook unsuccessfully used these trees as ship masts when exploring Norfolk Island. Large numbers of Norfolk Island Pines are produced in South Florida for the houseplant industry. The bulk of these are shipped to grocery stores, discount retailers and garden centers during November. Many of these are sprayed with a light coating of green paint prior to sale to increase their eye appeal.

External link

• Gymnosperm Database: Araucaria heterophylla (http://www.botanik.uni-bonn.de/conifers/ar/ar/heterophylla.htm)