The mushroom-like fungi appeared suddenly in Manchu Autonomous County of Xiuyan in Anshan City, according to the house owner, surnamed Sun.

"I didn't notice them until last week...When I accidentally coughed, the biggest of the fungi -- about 20 centimetres in diameter -- let out some white smoke, he said.

"I've invited all my friends and neighbours to the house, but no one can tell what the weird plants are or why they smoke," Xinhua news agency reported.

The fungi are not umbrella-shaped like most other fungi that grow in humid environment. Without a cap or a trunk, they stick on the cement wall with only tiny, string-like roots.

Whenever someone talks or coughs loudly in Sun's storehouse, even the smallest of the plants emit white smoke and "cowers" towards the wall, then turns back to normal after a minute or two.

Botanists from the Liaoning University say they have never heard of such a smoking fungus.

But Professor Liu Mingyu assumes the "smoke" is clusters of spores. "Sound waves cause vibrations that cause the spores to fall off the plants," he said.