ACACIA AURICULIFORMIS

ACACIA AURICULIFORMIS

  

Common name: Earleaf Acacia, Ear-pod Wattle, Papuan Wattle, Auri, Northern Black Wattle

Botanical name: Acacia auriculiformis     

Family: Mimosaceae (Touch-me-not family)

Geographical source

Native to the savannas of New Guinea, islands of the Torres Strait, and northern Australia, it has been widely introduced, e.g. in Fiji, India, Indonesia, Java, Malaysia, Niger, Nigeria, Philippines, Tanzania, Thailand, the Soloman Islands, Uganda, and Zanzibar.

Introduction: Earleaf Acacia is an evergreen, unarmed tree to 15 m (50 ft) tall, with compact spread, often multi-stemmed; young growth glaucous. Leaves alternate, simple, reduced to phyllodes (flattened leaf stalks), these blade-like, slightly curved, 5-8 in long. Flowers in loose, yellow-orange spikes at leaf axils or in clusters of spikes at stem tips; flowers mimosa-like, with numerous free stamens. Fruit a flat, oblong pod, twisted at maturity. It's roots are very strong and can break through concrete, ruining sidewalks and driveways and pushing out other vegetation. Used for the cultivation of the lac insect in India. This plant is native to southeast Asia, Indonesia, Papua New Guinia and Australia.

Species Type: Tree

Cultivation

It has been suggested as an interplant with long-term timber Dalbergias, itself serving as a short-term but renewable firewood source. Seeds, storable for 18 months in airtight containers, should be soaked in hot water for 24 hours. Sow in full light, allowing 6 days for germination (ca 80% germination after 2–4 weeks). To reforest grassland, burn and plant in holes ca 36 x 30 x 30 cm, spaced at 1–2.5 or 1–3 m if intercropped with Cassia siamea. Recent spacings have been 2.5 x 2.5 m.

Chemical composition: The gum contains 5.3% ash, 0.92% N, and 1.68% methoxyl, and ca 27.7% uronic acid. The sugar from the gum after hydrolysis, contained 10.1% 4-0-methylglucuronic acid, 17.6% glucuronic acid, 59% galactose, 8% arabinose, and 5% rhamnose (Anderson, 1978). Bark contains ca 13% water. triterpenoid saponins -- proacaciaside-I; proacaciaside-II; acaciamine;

Traditional medicinal uses: A decoction of the root is used to treat aches and pains and sore eyes; an infusion of the bark treated rheumatism (aborigines of Australia).

Role in the habitat: Acacias recover wastelands, returning nutrients to poor soils and providing shade for other plants to take hold. They do not produce a lot of pollen or nectar as food, but their plentiful seed supply is a valuable food source for animals (mainly birds and also small mammals), particularly in dry places. Various insects eat their leaves and wood, and sugar gliders and squirrels may eat their sap. The trees also provide shelter for animals; as well as epiphytic plants.

Flowers : June-October