Story: Shrubs and small trees of the forest
Page 8 – Pittosporums
Pittosporums are most familiar as small bushy trees with attractive foliage, grown widely in gardens. Of the 21 New Zealand species, about half are divaricating shrubs.
Some pittosporums are common throughout the country, growing in forest and scrub from the coast to subalpine habitats. Others have restricted distributions, and some are rare or endangered.
Pittosporums have small bell-shaped flowers. These are followed by woody capsules containing the sticky seeds that give the genus its Latin name – pittosporum means pitch seed.
Karo (Pittosporum crassifolium) is a small tree or shrub, conspicuous in coastal forest. It grows naturally on the Three Kings Islands and Great Barrier Island, and in the North Island from Te Paki south to East Cape. It is now widely naturalised throughout New Zealand, partly as a result of the dispersal of its seeds by birds.
Karo can reach 10 metres in height. Both its branchlets and the underside of its dark green leathery leaves are felted white or buff. In spring to early summer karo bears richly-scented flowers, coloured deep crimson to purple. The flowers sit neatly among the leaves at the tips of branches. Its distinctive large seed capsules are felted white or yellow, and open to reveal sticky black seeds.
A favourite scent
Fragrant plants were sought-after by Māori for use as scent or body lotion. Lemon-scented tarata was commonly used, as it was widely available. Its resinous sap and crushed leaves were mixed with plant oils such as tītoki and kohia.
Tarata – lemonwood
The largest New Zealand pittosporum species, lemonwood (P. eugenioides) grows up to 12 metres tall. It is a handsome tree, with pale bark and wavy-edged, mottled, yellow-green leaves with a distinctive pale midrib. A strong lemon scent is released when its leaves are crushed.
Lemonwood is common in forests throughout the North and South islands, growing from the coast up to about 600 metres. In spring, lemonwood bears profuse clusters of cream-yellow, highly scented flowers.
Kōhūhū – black matipo
A small tree or compact shrub, kōhūhū (P. tenuifolium) is common throughout New Zealand, particularly in regenerating forest and scrubland. It has dark branchlets and small, wavy-edged, pale-green leaves with a silvery sheen. Kōhūhū’s solitary, small, dark-red to black flowers are often overlooked, but the scent can be noticeable at night during spring.
Common divaricating pittosporums
Several twiggy, divaricating, lookalike pittosporums with small leaves are found in the lowland to montane forests of both main islands.
Pittosporum rigidum is an upright shrub with stiff, interlacing branches. It is up to four metres tall, and has whorls of lobed or toothed dark-brownish green leaves, and solitary dark red flowers. It is common in the North Island axial ranges and in north-west Nelson.
Smaller P. divaricatum also has dark red to black flowers and irregularly lobed juvenile leaves but a more open habit. Its pale green adult leaves have two distinct shapes – toothed or smooth-edged. This species is widespread in the lowland to montane beech forest and scrub of Canterbury, but is rare west of the Southern Alps.
Shrubby P. anomalum is the smallest of this group of lookalikes, reaching about one metre in height. Compact, with tightly interwoven, stout, reddish-orange branches, it has strongly scented yellow flowers.