Acacia paradoxa DC.

Scientific Name

Acacia paradoxa DC.

Description

Size and Growth Form

This species is a large shrub or tree that grows 2 to 4 metres (7 to 13 ft) tall, with a similar width.

Branchlet and Phyllode Features

It has ribbed branchlets that often arch downward, and is densely foliated. What appear to be leaves are actually enlarged petioles called phyllodes; these phyllodes are crinkly, with new growth covered in hairs.

Phyllode Dimensions

They are erect, asymmetrical, lanceolate-shaped, and measure around 30 millimetres (1.18 in) long and 7 millimetres (0.276 in) wide. The plant is also covered in long spines.

Flowering Characteristics

It typically flowers between August and November, producing axillary flower spikes holding small, bright yellow spherical flower heads.

Pod and Seed Traits

After flowering it forms brown pods 4 to 7 centimetres (1.6 to 2.8 in) long that hold hard black seeds. The seeds are oblong, around 6 millimetres (0.236 in) long and approximately 3 millimetres wide.

Spine Function

Spiny stipules growing at the base of phyllodes keep livestock from feeding on the plant or approaching it too closely.

Distribution

Native Range

Commonly called kangaroo thorn, this species is endemic to south-eastern South Australia, most of Victoria, eastern New South Wales, and south-eastern Queensland, and is widely distributed across Australia.

Regeneration Trait

It regenerates from seed after disturbances such as bushfire.

Naturalised and Introduced Range

It has become naturalised in parts of Western Australia and Tasmania, and has been introduced to other continents. In the United States, kangaroo thorn is a well-documented noxious weed in California.

Ecological Role

Ecologically, small birds including wrens use this plant as shelter and habitat, moths, butterflies and other insects rely on it as a food source, and birds also feed on its seeds.

Cultivation

Common Uses

This plant is grown as an ornamental or as a dense screening plant. It provides excellent habitat and food for birds.

Growing Conditions

It grows well in full sun or partial shade, and can be planted in dry to moist well-drained areas.

Propagation Requirements

Seeds require pre-treatment such as scarification before planting.