The shrub or tree typically grows to a height of 3 to 15 m (9.8 to 49.2 ft)^[2] can grow to a height of around 20 m (66 ft) and usually has a weeping^[3] or erect to spreading habit.^[2] It has hard, fissured and deep grey coloured bark and glabrous branchlets.^[3] The wood of the tree has a scent similar to cut violets.^[4] Like most species of Acacia it has phyllodes rather than true leaves.^[4] The glabrous, evergreen phyllodes are straight or slightly curved and have a narrowly elliptic or narrowly oblong shape. The phyllodes are usually 2 to 7 cm (0.79 to 2.76 in) in length but can be as long as 9 cm (3.5 in) and 3 to 22 mm (0.12 to 0.87 in) wide with three to seven prominent longitudinal veins. It blooms between March and June in its natural range producing simple inflorescences that occur in groups of one to four usually in the axils. It has spherical flower-heads are 4 to 8 mm (0.16 to 0.31 in) in diameter and contain 20 to 35 bright yellow flowers.^[2] Following flowering it will produce brittle firmly papery seed pods that are flat and straight but are constricted between seeds. The glabrous pods are 4 to 11 cm (1.6 to 4.3 in) in length and 6 to 12 mm (0.24 to 0.47 in) wide finely reticulated veins and often covered in a fine white powdery coating.^[2]

The species was first formally described by the botanist George Bentham in 1848 as part of Thomas Mitchell's work Journal of an Expedition into the Interior of Tropical Australia. It was reclassified as Racosperma excelsum by Leslie Pedley in 1987 then transferred back to genus Acacia in 2006.^[1] The specific epithet means tall and is in reference to the tall habit of the tree.^[2]

It has a wide-ranging but scattered distribution throughout inland parts of southern inland Queensland extending into northern and central New South Wales.^[3] In New South Wales it is found as far south as Condbolin and as far east as Warialda. It is found growing in sandy loamy soils as a part of open woodland or savannah grassland communities.

The bark of this species, like all Acacias, contain appreciable amounts of tannins and are astringent and can be used for medical purposes including for the treatment of diarrhoea and dysentery when used internally or used to treat wounds, haemorrhoids or some eye problems when used externally. The trees can also produce gum from the stems which is also taken internally to treat haemorrhoids and diarrhoea. The wood produced by the tree is close-grained, very tough and hard and elastic and is suitable for cabinet-work and instrument fretboards. It was used by Indigenous Australian peoples to make boomerangs and spearthrowers.^[4]

• List of Acacia species