Late Black Wattle, Acacia mearnsii, is flowering splendidly this season (although the rain this morning will affect the blossoms). Black wattles prefer dry slopes with shallow soil in open forests and woodlands. They are a very common tree in the lower parts of the Strathbogie Ranges landscape. Late Black Wattle grows readily from seed or suckers, particularly after fire, ploughing or ripping . Growth is usually very fast (to 15 metres) and the trees are short-lived. They have acquired a bad reputation with farmers because they die after 10 years, fall on fences, look a bit messy and become annoying ‘scrub’, but Late Black Wattle has a lot to offer.
It is useful to quickly create habitat structure and windbreaks . Fast growth and the ability to improve soil fertility make it an ideal nurse crop and suitable to be used with slower-growing eucalypts or other long-lived species. It tolerates frost and extended dry periods. It is excellent for controlling erosion on steep slopes . It is an excellent fuel , compared to other wattles, burns well and produces high quality charcoal . The timber can be used for cabinet work , joinery and flooring. It can be cut for emergency drought fodder. Wildlife love it . Seed eating birds such as rosellas, cockatoos and pigeons eat the seed. It is plant food for caterpillars of native butterflies and moths, which in turn attract insect-eating birds . Many species of beetles and their larvae feed on the foliage . Black cockatoos look for beetle larvae beneath the bark. Ants collect the funicles from fallen seed . Honeyeaters like to nest in the foliage. Black wattle is critical habitat for gliders and possums . The gum is food for Sugar Gliders. The flowers have an attractive perfume.
Acacia mearnsii establishes well when direct seeded. The seeds stay viable in the soil for around 50 years and there are up to 140 viable seeds per gram of seed. Like all acacias the seeds need to be scarified before sowing. For the past two seasons very little seed has been produced by our local wattle trees and the seedbank has needed to buy in from other areas. The tricky thing is that the seeds take over one season to reach maturity. If you look carefully at flowering time you will notice the small green seed pods from last years flowers back from the fresh blossom; these will mature by mid summer and they shed quickly when finally ripe. This years flowers will mature next year – always one season behind. Lightwood Wattle have a similar habit.
Koories used the gum to make spear bases. The wood was used for clubs , shields , boomerangs and spears. The bark , leaves and seed pods can be used to dye material.