Buckinghamia celsissima

Common name: Ivory curl

Other common names: Spotted silky oak


vory Curl is a timber and ornamental tree originating in Australia, its natural range limited to relatively small areas of humid tropical forest in the north-east of the country.

It is a tall tree in closely spaced forests, reaching heights of up to 30 m (100 ft) with a straight, buttressed trunk up to 40 cm (1.3 ft) in diameter supporting a narrow crown. On open sites, it is more typically 5 to 10 m (15 to 30 ft) tall with a densely branched rounded crown. The bark on young trees is grey and smooth, with age becoming rough, thick and fissured. Growth is moderate to fast, depending on the growing conditions. 

Leaves bronze-red or pink-tinged when young becoming dark glossy green with a tough, leathery texture. They change shape as they mature, from deeply lobed, in juvenile form, to entire, elongated-oval at maturity and remain on the tree throughout the year.

The flowers are creamy-white tubes coiled at the tip and closely arranged in bottle-brush-like flower spikes up to 25 cm (10 in) long. They come into bloom in summer in its native range, over a period lasting four to six week. The long spikes hang from the ends of the branches in profuse numbers, nearly hiding the green foliage from view and are sweetly fragrant. They are followed in autumn to winter by small pear-shaped fruit that mature to dark brown, then split open to release small winged seed.


It is cultivated occasionally as a landscape and street tree, particularly in eastern Australia, for its shapely form and striking floral display. The nectar-rich flowers nourish native bird and butterfly species and are useful to apiculture, providing both pollen for brooding bees and nectar for honey production, with the honey described as similar to Macadamia (Macadamia integrifolia), being light amber and mildly flavoured.

Ⅰvory Curl trees produce a heavy wood, averaging around 940 kgs per cubic meter (59 lbs per cubic ft), with pale, red-brown heartwood that is attractively patterned by spots, somewhat resembling scattered liquid droplets. Though heavy, the wood is not naturally resistant to rot and decay, which puts it in the non-durable hardwood class. The sawn timber is used mostly for interior flooring and joinery work and the roundwood for turnery and other decorative woodcraft. 


Grows naturally in moderately humid subtropical and tropical lowland to mid-elevation climates, generally in areas with annual lows of 13 to 23 °C, annual highs of 25 to 32 °C, annual rainfall of 1000 to 2300 mm and a dry season of 2 to 5 months. However, it reaches its best development as a timber tree in areas with annual rainfall of 1600 mm or more.


New plants are usually raised from seed, though cuttings have also been used with reasonable success. It performs best on rich, moist, free-draining loam and sand soils of a moderately acid to neutral nature, generally with a pH of 5.0 to 7.0, and on sites with full to partial sun exposure.

Problem features

There are no known problem features associated with this tree.

Where it will grow



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