This creature is not the sort of thing you would want to find in your salad.

The prickly, black and red caterpillar is turning up in gardens all over south-eastern Australia. It is the larva of the white-stemmed gum moth (Chelepteryx collesi).

It can grow up to 11 cm (4.5 inches) in length. And watch those hairs - they can give a poisonous prick.

"Look, but don't touch," says Kim Pullen, from Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO).

"A 1998 report in the Medical Journal of Australia cites two Canberra cases where patients ended up in hospital with allergic reactions after getting a handful of bristles. In one case, the hair came from a cocoon which was inside a letterbox," said the insect identification and advice officer.

"The hairs are there for a purpose - defence. They are tiny toxin-tipped barbs that are very hard to get out of your skin. The caterpillar looks fearsome enough to deter most people, but you can also come to grief with the cocoon, which is almost invisible on the shaggy trunk of a gum tree, so my advice is, 'hands off!'"

The caterpillars can be seen crawling on the ground or on tree trunks during January and February. They are found throughout south-eastern Australia into the Gippsland and coastal tablelands.

"They've been high up in gum trees since their eggs were laid in April or May," says Mr Pullen. The eggs hatch mid-winter to early spring and they have been feeding since, out of sight but gorging themselves on leaves. By summer they're ready to spin a cocoon, so they come down from the trees to find a quiet place to pupate.

"They are not looking for food, and they won't eat anything in the garden. They make their long, tapered cocoon out of a tough opaque silk, embedding their bristles in the walls to leave it resembling a stretched-out pin cushion."

Although the larva may look spectacular, the moth itself is a little less ostentatious with dull, grey-brown colours.