Acacia quadrilateralis

A medium shrub, growing up to 3 metres tall with a spindly habit.

It has a mostly coastal distribution, found in eastern Queensland (up to Bundaberg – Gladstone and north of Yeppoon), and north-eastern New South Wales, down to Sydney (north of Botany Bay), with a southern disjunct population at Ulladulla. It typically grows on sandy soils over sandstone as a part of open Eucalyptus forest and woodland communities, as well as heathlands.

Australian Wattles at least, can be broadly placed into 1 of 3 recognisable groups:

• Group 1: Those that produce juvenile compound-bipinnate leaves and then change to producing adult-phyllodes which are modified-flattened petioles which form the foliage. This is combined with flowers produced in globular balls or heads (or ovoid heads). The heads can be singular in leaf/phyllode axils or arranged in groups.
• Group 2: As for Group 1 but flowers are produced in longer rod-like spikes.
• Group 3: Those that never produce phyllodes and retain the juvenile compound-bipinnate foliage into adulthood. These always produce flowers in globular balls (which are secondarily arranged into panicle or raceme-like groups in many cases).

This species belongs to Group 1.

The phyllodes (resembling leaves) are slender, rigid and evergreen and are 6 cm long and 0.1 cm wide. They are square-shaped in cross-section.

Very small staminate flowers occur between July and September and are produced as singular globular heads in the leaf axils, containing 12 to 30 cream to pale yellow-coloured flowers.

The seed pods are dark brown and resemble a string of beads. The pods are up to 9 cm long and 0.4 cm wide.