Australian Tropical Rainforest Plants - Online edition

Palaquium galactoxylon (F.Muell.) H.J.Lam


Tree
Click/tap on images to enlarge
Flowers [not vouchered]. CC-BY J.L. Dowe
Fruit, three views, cross section and seeds. © W. T. Cooper
Scale bar 10mm. © CSIRO
Cotyledon stage, hypogeal germination. © CSIRO
10th leaf stage. © CSIRO
Family

Lam, H.J. (1925) Bulletin du Jardin Botanique de Buitenzorg Series 3 7: 107.

Common name

Cairns Pencil Cedar; Cedar, Pencil; Daintree Maple; Pencil Cedar; Red Silkwood; Silkwood, Red; Cedar, Cairns Pencil

Stem

Deciduous; often leafless around October. Exudate often slow and meagre, emerging from layers, mainly in the inner blaze. Lenticels tend to be in vertical lines.

Leaves

Petioles and twigs produce a milky exudate. Young shoots and younger leaf bearing twigs clothed in rusty brown hairs. Stipules caducous, tapering to a long narrow tip. Leaf blades about 6.5-13 x 2.5-5.5 cm.

Flowers

Flowers usually produced on the twigs below or back from the leaves. Calyx ferruginous or brown tomentose. Corolla glabrous throughout, lobes about 6 mm long, lobes longer than the corolla tube. Stamens 12. Ovary 6-locular.

Fruit

Fruits stalked, +/- ellipsoid, about 35-40 x 20-30 mm. Seeds about 25 x 12-20 mm. Testa firm but not particularly hard, hilum lateral, quite large, about 10 mm or more wide.

Seedlings

First pair of leaves elliptic to obovate, about 5.5-8 x 2.5-3.5 cm, apex acuminate. Midrib hairy on the underside of the leaf blade. At the tenth leaf stage: leaf blade obovate, apex acuminate, base cuneate, upper surface glabrous; petiole, stem and terminal bud clothed in rusty hairs; stipules small, elongate-triangular, hairy. Seed germination time 28 to 40 days.

Distribution and Ecology

Occurs in CYP and NEQ. Altitudinal range from sea level to 300 m. Grows in well developed lowland rain forest and gallery forest. Also occurs in New Guinea and the Solomon Islands.

Natural History & Notes

Fruit eaten by Torresian Imperial-pigeons. Cooper & Cooper (1994).

Produces a useful and decorative cabinet timber.

Wood specific gravity 0.56 Cause et al. (1989).

Synonyms
Sersalisia galactoxylon (F.Muell.) Benth., Flora Australiensis 4: 279(1868). Lucuma galactoxylon (F.Muell.) F.Muell., Systematic Census of Australian Plants : 91(1883). Bassia galactoxyla F.Muell., Fragmenta Phytographiae Australiae 6: 27(1868), Type: Ad sinum Rockinghams Bay secundum fluviorum ripas.
RFK Code
265
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