What is it?
A very fast growing, though thankfully short lived tree - popping up on cliffs, banks, hillsides, slips and cuttings. One of the few flowering trees around in winter, brush wattle is conspicuous now with greenish-yellow bottlebrush-like flowers. It is reasonably common in the North Island, though rarer in the south.
Why is it wicked?
Now you don't see it, now you do! It can seem only a matter of months before a few tiny saplings suddenly become tall stands of solid looking trees. Brush wattle is renowned for its rapid growth and knack of producing heaps of long-lived seeds held in seed pods and transported in soil, gravel and water. Native forest will establish under wattle and eventually overtop it, so it's really only around low-growing or open vegetation that it's an environmental problem.
What can you do?
Brush wattle likes lots of light. If you cut one down, it's likely that you will just encourage even more brush wattle seedlings to develop. If you can't wait the 20-30 years for the bush to take over or brush wattle trees have only recently appeared you can cut them down but stumps will need treating with herbicide - check out www.weedbusters.org.nz for more control options. The most important thing is to make sure you are ready to pull out any new seedlings and try to replant with desirable species as you go.
Kohuhu (Pittosporum tenuifolium) is a hardy tree of similar size that is great for revegetation. Kanuka (Kunzea ericoides) and manuka (Leptospermum spp.) are also quick to establish and have attractive flowers.