Lawn looking lunar this Winter?

Corbie grub.

The Exton Gardener

There are two main lawn pests in Tasmania. The first is the infamous corbie grub.

Strictly speaking, it’s a ground dwelling caterpillar which pupates into a moth.

There are two species in Tasmania, Oncopera rufobrunnea and Oncopera intricacata (the winter corbie). It is the latter what would be active now.

The thing with corbie grubs is that they live in tunnels. The opening is covered with webbing and debris.

If you have a balding patch in your lawn you can soon see if is caused by corbie grubs by clearing any loose debris away.

Boys used to hunt for corbie grubs with a length of wire poked down the holes.

Redheaded cockchafer larvae.

Now the prevailing wisdom seems to be to flood the area with soapy water.

I have tried this with little success and I’m dubious about the damage some detergents can cause to the microbiology of the soil.

A trickling hose works far better and it can take about five minutes of flooding the area before the shiny heads pop out of the tunnel entrances.

I grab them with secateurs and they can be dispatched immediately with a snip or fed to the chooks. (I did have a cat once who would eat them...but that’s another story...)

The other lawn pest is the cockchafer, specifically, the red-headed cockchafer pupae, which hatch into a largish beetle, (Adoryphorus coulonii.)

It is no use flooding the area with water, soapy or otherwise, or even dousing the area with chemicals which may work on the blackheaded cockchafer but not on the redheaded.

These larvae won’t come to the surface. They live all their pupal life underground, feeding on the roots of not only your grass, but other herbaceous plants.

Birds may sometimes dig them up, but bandicoots love them, hence the moon craters.

Of the two species of bandicoot in Tasmania, the Southern brown bandicoot (Isoodon obesulus) looks like a large rat with a short tail and nose.

These fellows are enthusiastically tearing up my grass in search of their prey - and it looks pretty bad.

What to do? Well, I have to be philosophical about this.

Bandicoots are endangered and they’re rather endearing marsupials. I’m going to let them do their thing and topdress in spring...