Prickly acacia

Vachellia nilotica, Fam. Mimosaceae

A shrub to spreading tree to 10m tall with axillary spines up to 50mm long. Previously Acacia nilotica subsp. indica.


Weed Category:	Restricted invasive plants Category 3 Plants declared invasive under the Biosecurity Act 2014, that are present in QLD. Not to be distributed or disposed of.
Weed:	Yes
Form or habit:	Shrub, Small tree
Family:	Mimosaceae
Leaf:	Compound Opposite Compound, opposite, bipinnate, fern-like with 4-10 pairs of pinnae each with 10-25 pairs of leaflets.
Flower conspicuous:	Conspicuous
Flower colour:	Yellow
Flower description:	Yellow, in fluffy spherical heads, typical wattle.
Fruit conspicuous:	Conspicuous
Fruit colour:	Grey, Green
Fruit:	Dry
Fruit description:	Pods 100-150mm long, green-grey and downy, flat, deeply indented like a necklace around the 8-15 seeds. Seeds flattened, greyish, oval, with a very long viability.
Habitat:
Distribution
Food source for:
Toxicity:	No toxicity known
Origin:	Pakistan, Africa, Middle East and south west Asia
Notes:	Spread by: seeds germinate in large numbers under the parent plant, dispersed by water, in animal manure (e.g. cattle) and by contaminated soil on/in vehicles and machinery. Originally introduced as a fodder tree and also planted for shade. Leaves and pods high in protein. Invades/threats: drier areas of the region where it replaces remnant vegetation, forms thorny thickets which outcompete grassland species and restrict mustering, vehicle and wildlife movement. Grows on heavy clay soils. Category 3 restricted invasive plant under the Biosecurity Act 2014, it must not be given away, sold, or released into the environment without a permit. The Act requires everyone to take all reasonable and practical steps to minimise the risks associated with invasive plants and animals under their control. This is called a general biosecurity obligation (GBO).
Information sources:	Mackay Regional Pest Management Group (2018) Weeds of the Mackay Whitsunday Region Second Edition.