Aleurites

Aleurites.

Family Euphorbiaceae > Subfamily Crotonoideae > Tribe Aleuritideae > Subtribe Aleuritinae.
There are only 2 species that are native from India and China down to Queensland and New Zealand.

They are evergreen trees up to 40 m high with simple alternate leaves.
Young twigs, leaves and inflorescences have dense pale or rust-coloured simple and stellate hairs.
The smooth bark has long vertical fissures.

The leaves are on a petiole up to 20 cm long.
The 1 mm stipules fall early leaving small circular scars.
There are 2 small glands on the upper surface of the petiole where it joins the blade.

The leaf blades are 20 to 40 cm long and up to 30 cm wide.
They are commonly ovate to lanceolate but may have up to 5 (7) triangular lobes.
The tips are pointed but the base can be very variable.
Three to five main veins radiate from the top of the petiole.
Young leaves are pink or brown due to a thick covering of hairs.
Hairs are gradually lost although some may remain along the veins especially on the lower surface.

The conical terminal inflorescences are branched clusters (panicles) up to 15 or 20 cm long.
The bracts are up to 5 mm long and, like the branches are densely hairy.
The small white or cream flowers are mostly male with only 1 (few) female on each branch.

The calyx has 2 to 4 ovate lobes that are hairy externally and may be of different sizes.
The 5 or 6 free petals, with rounded tips may have hairs.

Male or staminate flowers, on thin pedicels have up to 32 stamens in 4 whorls.
Those in the outer whorls are free while the filaments of the inner ones are fused forming a column.
There are hairs on the filaments.
The basi- to dorsi-fixed anthers, opening inwards through slits may have some hairs.

There is a nectiferous disc with 5 small lobes.
There is no ovary.

The slightly larger female or pistillate flowers are on a shorter and thicker pedicel.
The densely hairy ovary has 2 or 3 (4) locules each with one ovule.
The 2 thick styles, with or without hairs are fused for up to half their length.

The fruit are drupes with a thin fleshy outer layer and 1 or 2 seeds inside a hard woody shell.
They vary in shape and the presence or absence of stellate hairs.
The roughly spherical ridged seeds may be flattened front to back.

Aleurites moluccanus is widely cultivated while the native A. rockinghamensis is restricted to N. E. Queensland.

J.F.

Species