Acacia cultriformis (Knife-leaf wattle) is a large shrub growing up to 4m high with silvery triangular leaves and large golden flower heads which appear in spring. It is frost and drought hardy and adaptable to a wide range of soil types. This ornamental wattle occurs naturally in inland parts of NSW and southern Queensland. Must be grown from seed. There is a prostrate form called 'Cascade' which looks stunning cascading over large rocks or walls.
Acacia pycnostachya is a small rare tree which grows on Bolivia Range in northern NSW. It flowers in October and has large fantastic rod flowers. This is fascinating. Some years ago I suggested planting this as a wattle that can feature at Bali commemorations because most of the other wattles are finished by that time. I sent out about 500 packets of seed to listeners of Australia All Over. The video is the first bit of feedback I've had from that campaign.
Acacia decurrens (Black wattle) is a large tree with ferny leaves and sprays of golden flower heads in spring. It is frost and drought hardy, very fast growing and suited to farm plantings, woodlots and windbreaks. It grows naturally in open forests from the Hunter Valley in NSW to the ACT. It may naturalise in good conditions.