Acacia podalyriifolia

Mount Morgan wattle


Acacia podalyriifolia

G.Don 1832

pronounced: uh-KAY-shuh pod-al-ih-ree-if-FOH-lee-uh

(Mimosaceae — the hibiscus family)

common names: Mount Morgan wattle, Queensland silver wattle

native 4Acacia is derived from the Greek word ακις (akis), a thorn or spike; podalyriifolia means that the plant has leaves like those of the Podalyria genus.

This is one of the most popular and widely cultivated of the wattles. It is a tall shrub or small tree that can reach about 5 m in height, with a similar spread. Like most members of the genus, the mature plant does not have true leaves, but has leaf-like flattened stems called phyllodes. In this species the phyllodes are a silvery grey in colour. The flowers occur in ball-shaped clusters in the axils of the phyllodes, and are golden yellow in colour. Flowering occurs mainly in late winter and early spring.

Mt Morgan Wattle occurs naturally in Queensland from Mt Morgan inland to west of the Carnarvon Range and south-east to Stanthorpe, where it is quite common; there are some plants in the north of NSW close to the Queensland border; and it has become naturalized in the south-west of Western Australia, and in parts of South Australia.

The branchlets are pruinose, velvety with dense, straight, soft and spreading hairs, very rarely glabrous. The phyllodes are elliptic to ovate or sometimes obovate, 2 – 4 cm long by 1 – 2.5 cm wide, with an abruptly tapering point, thin, usually silvery grey to glaucous, hairy like the branchlets, but the hairs are sparser, and the midrib is off-centre.

The inflorescences are racemose; the raceme axes are 3 – 11 cm long, stretching out past the phyllodes, also hairy like the branchlets; peduncles are 5 – 10 mm long, again hairy like the branchlets. The heads are showy, fragrant, globular, 5 – 8 mm in diameter, usually with 15 – 50 flowers on each raceme.

Pods up to 12 cm long are produced, 1.5 – 2 cm wide, leathery, velvety. and pruinose when young, but sometimes becoming glabrous with age. They dehisce unilaterally, with the margins sometimes undulate. The seeds are longitudinal, oblong, 6 – 7.5 mm in length, dull and black. The aril is club-shaped.

This wattle is fast-growing, and may flower in its second year. It seeds freely, and can be invasive in areas outside its normal habitat. It has become an invasive pest in some southern areas. It is naturalized in Malaysia, Africa, India and South America. There have been several garden hybrids developed in Europe with Acacia podalyriifolia as one parent. The species is frost-hardy down to about –7ºC, which makes it and its hybrids well suited to cooler climates.

This is a very beautiful tree, and not only when it is in flower – its foliage is also very attractive. It is also a host plant for the larvae of some butterflies, especially the Fielder’s Line Blue (Prosotas felderi) and the Tailed Emperor (Polyura sempronius).

Photographs taken in Picnic Bay, 2010
Page last updated 24th September 2018