Common Name: Kurrajong

General Information

Brachychiton populneus is a wide-spreading evergreen or semi-deciduous tree with a dense crown; it can grow 10 - 20 metres tall. In open situations the tree has a short, stocky bole which may reach a diameter of 50 - 100cm[].
The seeds and the root were popular foods for the Australian Aborigines and the seed in particular is also appreciated by Western palates. The plant is harvested from the wild and is also commonly grown as an ornamental.

Known Hazards

The seed capsule contains irritant, glochid-like, hairs and should only be handled when wearing gloves[].

Botanical References

,

Range

Australia - all mainland states, but mainly in Victoria, New South Wales, Queensland

Habitat

Coastal and sub-coastal areas on a variety of soils but favouring limestone[, ]. Drier lowland woodlands and rocky hillsides[].

Properties

Edibility Rating
Other Uses Rating
Habit	Evergreen Tree
Height	15.00 m
Cultivation Status	Ornamental, Wild

Cultivation Details

Brachychiton populneus is a plant of the arid to moist tropics, subtropics and warm temperate zones, where it is found at elevations up to 1,000 metres. It grows best in areas where annual daytime temperatures are within the range 25 - 32°c, but can tolerate 13 - 38°c[]. Mature plants can be killed by temperatures of -5°c or lower, but young plants will be severely damaged at -1°c[]. It prefers a mean annual rainfall in the range 450 - 750mm, but tolerates 250 - 1,000mm[].
Prefers a well-drained moderately fertile, slightly acidic soil in a sunny position[, ]. Succeeds in most soils, tolerating dry soils in Australian gardens[, ]. Plants dislike wet soils, especially in the winter[]. Prefers a pH in the range 7 - 8, tolerating 6.5 - 8.5[]. Established plants are drought tolerant[].
Trees can be cut back into old wood and usually resprout well[].Requires a minimum temperature of 7 - 10°c[, ]. Plants are hardy to at least -7°c in Australian gardens[], though this cannot be translated directly to British gardens due to our cooler summers and longer, colder and wetter winters. This plant is very doubtfully hardy outdoors in Britain, though plants in an unheated greenhouse survived a prolonged cold period in 1996 - 97 when temperatures sometimes went down to -8°c[].
Prefers a well-drained moderately fertile soil in a sunny position[]. Succeeds in most soils, tolerating dry soils in Australian gardens[, ]. Plants dislike wet soils, especially in the winter[].

Edible Uses

The seed can be eaten raw or roasted[, , ]. It can also be ground into a powder and made into bread, pancakes and other baked goods[]. They have a rich, nutty, earthy flavour[]. A popular Aboriginal food, they are also acceptable to western palates, especially when roasted[]. Very nutritious, containing about 18% protein, 25% fat plus high levels of zinc and magnesium[].

The roasted seed is used as a coffee substitute[, ].

Root - cooked[, ]. The yam-like root is often much broader than the stem above it[, ]. The tap-roots of young trees, and the young roots of old trees, are used[]. When boiled they have a flavour similar to that of turnips, but sweeter[]. A popular food item with the Australian Aborigines[].

The honey-coloured sap was a popular Aborigine food[].

Medicinal

None known

Other Uses

A strong fibre is obtained from the inner bark[]. It is used for making cordage, nets and dilly bags[, , , ].

A gum exudes from the trunk[]. Somewhat like gum tragacanth (Astragalus spp.) in appearance, it is produced abundantly[]. This gum, however, does not thicken water, except to an almost inappreciable extent, and, therefore, could not have the same economic uses to which the very viscid tragacanth is put[].

The wood is soft, fibrous and useless[]. The heartwood is light, soft, open textured and of poor strength and durability. It is used for lattice construction and as a softwood for interior furnishes[].

Propagation

Seed - we have no details for this species but suggest sowing the seed in spring in a greenhouse. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts.
Cuttings of mature wood of the current season's growth.