HONOLULU -- A pest with a nasty sting has turned up at a nursery on Oahu, state agriculture officials said.

The stinging nettle caterpillar first turned up in Hilo in 2001, officials said. It came through an illegal shipment of seedlings from Taiwan, according to officials.

The problem has not been completely wiped out on the Big Island. Complaints are now coming in from home gardeners, officials said.

The major problem with the caterpillars is not so much the effect on plants, but on people.

"If you rub against the caterpillar, it has a very strong burn and that's why they called it the stinging caterpillar or nettle caterpillar, and it can burn for a few hours," said Neil Rheimer of the state Department of Agriculture.

State officials want to avoid alien species like these from gaining a hold in the islands.

It is likely the source was a shipment bought from a Big Island nursery about a year ago, officials said.

"It's possible it may already have spread, but it wouldn't just be this nursery. Anybody who is bringing plants from the Big Island is running this risk," Rheimer said.

The state is been setting up traps to monitor the nursery. They hope to attract the moths that lay eggs and spread the problem.

The caterpillars were discovered on raphis palm trees. Workers at a Central Oahu nursery complained about being stung last week. The department would not name the company, saying only that the workers had moved the palm trees to a second location.

If you have palms, officials said you should check the base of the plants for the cocoon.

"This sort of material here, you just pull that back and you see a little brown thing about the size of a pea and that will be a cocoon," Rheimer said.

The state said it is still too early to tell if the infestation has been controlled. Officials said that you should call the state's pest hot line at 643-PEST if you spot the insects.