Bizarre find inside Aussie home 'a sign of much bigger issues'

It's not every day you wake up to find aliens in your home, but that's how one little boy feels after a strange growth appeared inside his house overnight.

His mum revealed they woke to find two large mushrooms sticking out of the cornice in one of their rooms which she claims "wasn't there" the night before, and now she has "a 5-year-old thinking aliens are taking over our house," she said.

The Sydney woman shared a picture of the bizarre find on Facebook asking if anyone knows what it could be. The image shows two long stalks poking out of a newly-formed hole in the plaster with liquid stains dripping down the wall.

Mushroom a 'sign of much bigger issues'

The growth in the image has been identified by experts as "a fungus sporing body" called Coprinus, — put simply, an ink-cap mushroom.

"The spore-producing mushroom expands rapidly and then liquifies releasing its spores in a dark fluid suspension that in this case has run down and stained the walls," David Catcheside, a biology professor told Yahoo News Australia.

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While "unlikely to be toxic and not dangerous to touch", it's "most likely a sign of much bigger issues of the housing conditions", Benjamin Schwessinger from Australian National University added.

"The wall must be in a pretty bad shape as the mycelium of the fungus must be all over," he told Yahoo. " It is likely very damp and the fruiting body (the stuff you see in the picture and most people call mushroom) can just grow overnight."

Mushrooms can grow 'within hours'

Teresa Lebel, a taxonomist and ecologist, said it happens "rapidly," sometimes "within hours". However, Catcheside, from Flinders University, explained "it has probably been slowly growing on damp timber in the ceiling structure or possibly on fibres within a fibrous plaster" before poking through the wall.

"The mycelium would have been growing slowly and once it gets to an adequate size it forms a knot of mycelium that develops into a ball of tissue that differentiates into what will become the mushroom when it expands," he explained. "The development takes significant time but the expansion into the mushroom happens fast, indeed overnight. It then breaks down into the spore-bearing fluid over a few hours."

Mushrooms likely a sign of 'rotting wood'

Lebel, who works on fungi, said when mushrooms are present "there is usually a moisture problem behind the wall or ceiling". "Mushrooms like cool, damp places to grow in," she explained.

"Then when the conditions are right will push the mushrooms out of the rotting wood or sometimes even insulation (paper/wood based) to release the spores."

She said it's "probably a good idea to get someone in to check the ceiling above, and increase ventilation in the roof space and the room where the mushrooms fruited if you can reduce moisture."

But the mushroom can easily be removed safely using gloves. "Wipe any mess off the walls with warm soapy water and dispose of the rag in the bin or compost. You could then use an alcohol wipe to clean the area further or spray a mould/grease/ grime disinfectant and wipe clean. Try to seal the hole (if there is one)."

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