Acacia quadrilateralis, commonly known as the Square-stemmed Wattle, is a spindly shrub native to open Eucalyptus woodlands and dry sclerophyll forests in southeastern Queensland and northeastern New South Wales, Australia. This perennial plant typically grows up to 10 feet tall and is characterized by its slender, rigid, quadrangular phyllodes, which are a unique adaptation in place of true leaves. From July to September, it produces cream to pale yellow spherical flower-heads that are moderately showy, followed by distinctive dark brown seed pods that resemble strings of beads.

The Square-stemmed Wattle is valued for its drought tolerance and ability to thrive in poor, sandy soils over sandstone, making it suitable for xeriscaping and restoration projects in similar habitats. It is also used in ornamental plantings for its unique foliage and interesting flower-heads. In cultivation, it requires well-drained soils, full sun exposure, and minimal water once established. While not commonly afflicted by diseases, it can be sensitive to root disturbance due to its adaptation to specific soil conditions.CC BY-SA 4.0