Australian Tropical Rainforest Plants - Online edition

Alphitonia excelsa (A.Cunn. ex Fenzl) Benth.

Shrub (woody or herbaceous, 1-6 m tall)
Click/tap on images to enlarge
Flowers and buds. © Barry Jago
Leaves and Flowers. © CSIRO
Leaves and Flowers. © CSIRO
Scale bar 10mm. © CSIRO
Scale bar 10mm. © CSIRO
10th leaf stage. © CSIRO
10th leaf stage. © CSIRO
Cotyledon stage, epigeal germination. © CSIRO
Cotyledon stage, epigeal germination. © CSIRO

Bentham, G. (1863) Flora Australiensis 1: 414.

Common name

Asg, Red; Humbug; Leatherjacket; Coopers Wood; Mountain Ash; Soap Tree; Red Tweedie; Sarsaparilla; Red Almond; RED ASH


Usually encountered as a small tree 4-20 m, less than 30 cm dbh but recorded to 40 cm dbh. Bark usually somewhat fissured and corky towards the base of the trunk.


Leaf blades about 3-18.5 x 1.2-6 cm, white or whitish on the underside. Stipules long and narrow, about 3-10 x 1 mm, gradually tapering to a fine point. Freshly broken twigs emit a faint sarsaparilla or liniment odour. Young shoots rusty hairy.


Flowers greenish. Calyx lobes acute, about 1.5-2 mm long. Petals hooded, about 1.5 mm long. Stamens enveloped in the petals. Disk thin, surface not corrugated. Style extended at anthesis.


Fruits 5-9 mm diam, globular. Mesocarp black and glossy or powdery at maturity. Seeds inflexibly attached to the receptacle.


Cotyledons ovate, elliptic or obovate, about 8-16 x 9-11 mm. First pair of leaves toothed, undersides clothed in matted hairs. At the tenth leaf stage: leaf blade underside clothed in white, downy hairs; hairs on stem erect, pale brown. Stipules hairy, linear, up to 3 mm long. Seed germination time 11 to 37 days.

Distribution and Ecology

Occurs in WA, NT, CYP, NEQ, CEQ and southwards to south-eastern New South Wales. Altitudinal range in northern Australia from sea level to 800 m. Grows in open forest, monsoon forest and dry rain forest.

Natural History & Notes

Food plant for the larval stages of the Large Green-banded Blue, Small Green-banded Blue, Copper Jewel, Fiery Jewel and Indigo Flash Butterflies. Common & Waterhouse (1981).

The leaves possess a high saponin content sufficient to make a froth if they are crushed and shaken in water. Cribb (1981).

Sometimes grows large enough to produce millable logs. Produces a useful general purpose timber.

Wood specific gravity 0.77. Cause et al. (1989).

Alphitonia excelsa (Fenzl) Benth. var. excelsa, Comprehensive Catalogue of Queensland Plants : 837(1913). Colubrina excelsa Cunn. ex Fenzl, Enum. Pl. Hueg. : 20(1837), Type: Australia, A. Cunningham (?). Alphitonia sp. Forty Mile Scrub (B.Hyland 25763RFK): Phrase name.
RFK Code
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