Sunday 15 July 2007

Fungus or caterpillar?

I was fairly sure I would find what I was looking for. There is a group of Black Wattle Acacia mearnsii growing on our bush block at Homerton and in previous years I had found the Vegetable Caterpillar Cordyceps gunnii growing under them, so that was where I headed. Cordyceps are wonderful fungi and I love showing them to the uninitiated, especially children. There is a lovely sense of horror and disgust mingled with astonishment when they see a fungus growing out of the head of a large dead caterpillar, a moth larvae. We were expecting a family of children to visit hence my reconnaissance. I was pleased to find them growing in abundance under the wattles. The pleasure was doubled when I found the colony of Trim Orchids nearby. This area is entirely natural regrowth as a result of putting up a fence about twenty years ago to keep stock out, so its very rewarding to see nature getting back to business.

Cordyceps gunnii

Next day, armed with a spade, I took the boys down to do some 'excavation', and was astonished to see that a lot of the fungi had been pulled from the ground. They hadn't been eaten but there were very few with the caterpillar part still present so I'm puzzled.

Cordyceps gunnii pulled from the ground

Was the caterpillar broken off as the fungi was being pulled up? I tried pulling several very gently out of the wet ground and the caterpillar broke off every time, so I don't know how an animal could have been more successful.
Was the fungi pulled up just to eat the caterpillar?
What animal did it and how? Echidnas? Possums? Kangaroos? A bird?

Now a true naturalist or scientist would have gone back at night with a spotlight. Not me. I was already exhausted from sitting up too late to watch some mad bike riders race around Europe.

2 comments:

Duncan said...

I've been looking for Cordyceps gunniifor the last couple of months without success, looks as if I'd better get out into the bush again. We have another species up here too, the branched fruiting body is only a couple of inches tall, haven't found out the specific name yet. It's a great time for greenhoods too.

Boobook said...

Hi Duncan
All of last week I looked for Cordyceps in the bush without success. The only place I have ever found it is on the edges of the bush under Black Wattle.