New Zealand’s coastal forest is made up of plants that can tolerate salty winds from the sea. These forests generally lack large emergent conifers, and have fewer vines and epiphytes. Coastal forest usually has a dense wind-shorn canopy of broadleaf trees, and is not very tall.
Species of the coastal forest
In northern New Zealand, pōhutukawa (Metrosideros excelsa) dominates the coastal forest. Pōhutukawa has many spreading trunks and rough, flaky bark. Masses of aerial roots grow down the trunks or hang in mid-air, and the dark green leaves have woolly undersides. Pōhutukawa often overhang the sea and are splashed by waves.
Karo, ngaio and taupata also grow in coastal forest. Karo (Pittosporum crassifolium) has leaves that are smaller than pōhutukawa’s, but also woolly beneath. Its three-valved seed capsules contain sticky seeds. Ngaio (Myoporum laetum) has leaves that show translucent oil glands when held up to the light. Taupata (Coprosma repens), with its very shiny leaves, is the smallest tree in the coastal forest. In exposed places taupata crouches close to the rocks, but with shelter it grows into an erect shrub.
Away from direct salt spray, several other trees grow. All are related to tropical plants. The handsome pūriri (Vitex lucens) has large compound leaves (made up of a number of leaflets), tubular crimson flowers and large red berries. It is related to the tropical mahogany. Karaka (Corynocarpus laevigatus) is another common coastal tree, and has simple dark green leaves and orange berries the size of small plums.
Underneath, the coastal forest is often fairly open. A thick litter of large leaves and leaflets covers the ground. There may be an undergrowth of kawakawa (Macropiper excelsum), a shrub with distinctive heart-shaped leaves. It is related to Fiji’s kava plant, and the Asian plant that is the source of pepper. Ferns are dotted here and there.
Pōhutukawa and pūriri do not occur naturally further south than Taranaki and the East Cape.
Subantarctic coastal forest
On the subantarctic Auckland Islands, the low coastal forest on sheltered shores is dominated by southern rātā. There are also a few smaller species and some ferns on the forest floor. The dense, wind-smoothed forest roof is a striking sight when the red-flowered rātā is in bloom.