Acacia are woody legumes in the form of small shrubs to large forest trees, which occur naturally on all inhabited continents except in Europe, especially in tropical and subtropical regions of Asia, Africa, Central and South America. Acacia occurs in both extremely humid and very dry ecosystems. Most acacia have long-lived seeds that can withstand fire and remain viable. There are more than 1,500 species, of which around 1,200 are in Australia. Some of these species are severely or critically endangered. Others, such as the now popular for musical instruments Victorian Blackwood (Acacia melanoxylon), are now widely used worldwide and are considered virtually invasive weeds. Acacia wood is used as a tonewood for ukuleles; it is denser and heavier than mahogany.

Acacia melanoxylon (Victorian Blackwood)