Acacia leptostachya

Townsville wattle


Acacia leptostachya

Benth. 1864

pronounced: uh-KAY-shuh lep-toh-STAK-yuh

(Mimosaceae — the hibiscus family)

common name: Townsville wattle

native 4Acacia comes from the Greek ακις (akis), a thorn or spike; leptostachya is from λεπτος (leptos), slender, and σταχυς (stachys), an ear of corn (as in the sense of a spike of flowers).

This is the dominant wattle species on Magnetic Island, and decorates our hillsides with a lovely swathe of yellow colour in mid-winter. The shrub varies in shape and size depending on the soil in which it grows, and can grow up to about 5 m, but in most of its habitat here it reaches only about 2 m.

The species is spread across eastern and central Queensland from the east-central part of Cape York Peninsula near Coen as far south as Maryborough and Charleville, in deep sand and skeletal soil on sandstone or granite in eucalypt woodlands, open eucalypt forests or hummocky grassland.

It has dense foliage and a rounded shape. Young growth of both branches and phyllodes is hairy, and the bark is dark grey and fissured.

The phyllodes are stiff, straight or shallowly curved, and narrow, although in young trees this varies. They are leathery, grey-green, from 3 – 9 cm long and 0.3 – 1 cm broad, and have many longitudinal veins.

The bright golden yellow spike flowers are from 2 – 4 cm long, and occur, usually in pairs, in the leaf axils. The flowering period is usually from June to August, and then narrow, curved pods are produced.

These pods are up to about 6 cm long with the seeds either longitudinal or transverse in the pod, the latter in the broader pods. Pods are dark brown in colour, occur in clusters and are twisted and curled. The pods remain on the tree after the seeds have fallen from them. The seeds themselves are 3 – 4 mm long, shiny and brown, with a small aril.

Very often galls are seen on our local trees, caused by wasps.

As the tree never achieves a great size, the size of the timber available is limited; but, as there is only slight movement during the drying process, it can be kept as a whole log, which means that objects of a fair size can be turned from it. The timber works better than most of the other local small wattles. It is of medium weight with a slightly open grain that machines and sands well: a good finish can be obtained with not too much effort.

Photographed in Picnic Bay 2008-2016 and Horseshoe Bay 2014
Page last updated 22nd December 2019