What’ll happen to the wattles ?
You may have noticed the rusty-browning and defoliation of wattle trees around the district recently. This was particularly noticeable to us on a trip to the Strath Falls the other day – the effect can be seen in the centre of the photo at left, where much of the dense post-fire regrowth of wattles appears to be dying.
The wattle species affected are those with feathery bipinnate foliage: Silver Wattle (Acacia dealbata) and Black Wattle (Acacia mearnsii). The culprit is what appears to be a small caterpillar, as seen in the photo at right (click on it for a closer look).
Fireblight Beetle larva
In fact the offender (approx. 1 cm long) is the larva of the Fireblight Beetle (Peltoschema orphana – formerly Pyrgoides orphana) as seen at left. The beetle is native to south-eastern Australia and feeds on Silver and Black Wattles.
The defoliation of these wattles is another interesting aspect of the post-fire recovery of the bush. Not all of the wattles will recover and, in the meantime, the thinning of the canopy will allow other native plants (and unfortunately weeds!) to regenerate.
Focus On Fauna 
These guys are popping up everywhere at the moment, noticeable outside the fire affected areas too. Adults are starting to emerge now. I have started a collection on http://www.natureshare.org.au to map their distribution. http://natureshare.org.au/collection/261/ There is a map and photos of the adults. Be great if other people could add to this collection to see how many areas are affected and compare it to what we notice next year.
James.
Thanks James. Great shot of the adult beetle. Do you know if they also feed on the same wattle foliage?
David
Hi David, From what I have read the adults also feed on the same plants and I have seen adults on the few trees that still have some foliage left. See http://natureshare.org.au/observation/7020/ . James.
This is even happening in Northern Tasmania, and in areas that have never seen a bushfire!