To the children it's a place to play; to the council it's a death-trap. So officials in Nelson have ordered a tree house to be demolished because it's too unsafe for children to play on.

The offending structure, two platforms built on council land near Orphanage Creek, will be torn down next week by the Nelson City Council.

A tyre swing has the all-clear to stay but will be monitored and may be removed in future.

A letter tacked to the tree on Friday was found by a boy who uses the hut.

The notice was posted on a Trade Me forum by his father yesterday. "I'm sorry to inform you that we consider that your structure in this 'crack willow' tree is unsafe and is a risk to your safety and the safety of others [who] may use these tree platforms," said the letter.

The user wrote: "My son brought this letter home from their tree hut last night. I had a good laugh at it and all the PC crap that goes with it."

Nelson City Council parks team leader Lindsay Barber said the council was tipped off by a concerned member of the public.

The hut's platform was "a bit wobbly" and didn't look particularly secure, he said.

Barber said the council was caught between letting kids be kids and protecting the public: "We have to take a more conservative line with it."

He said "no one wants to ruin anyone's fun", but if a child was hurt it could come back on the organisation.

"The general public are very, very unforgiving when it comes to the council. At the end of the day we've got to cover our tracks with it a little bit."

Barber acknowledged such a situation would not have happened 20 or 30 years ago but said "we're in a different situation in the 21st century".

Nelson city councillor Pete Rainey said he would speak to the staff who issued the letter tomorrow.

He said it would be sad if a kid couldn't have fun building a tree hut, but the council had a public safety responsibility.

But such actions were killing the nation's adventurous spirit, said Scouts New Zealand spokesman Ed Kulik.

"Kids these days are wrapped in cotton wool. They need to be able to climb trees - and fall out of them sometimes."

He said anything "remotely hazardous" required an unnecessary amount of forms and precautions..

"I'm disappointed that we can't teach our children what is safe and that they can't experience danger so they know how to get out of it."