Queenstown Lakes District Council arboricultural officer Tim Errington wanted people to be less adventurous around the tree and not climb it when the water level was low.
"Willow has a relatively thin bark that can be easily crushed or worse, dislodged from the tree.
"Any damage of the protective bark layer has two results — the wood beneath the bark becomes exposed to fungal pathogens and wood-digesting insects, which can enter the tree and result in the eventual demise of the tree, and it disrupts the flow of food or sugars to the roots, which can eventually have a detrimental effect on the wellbeing of the tree, which none of us want to happen."
He said willow wood was particularly fragile and easily broken.
"As any tree requires a certain amount of leaves to sustain itself, any reduction as a result of branches being broken or fractured will have a direct effect on the tree’s ability to photosynthesise.
"So, when visiting the famous Wanaka tree, we’d ask people . . . to be satisfied with a sustainable and tree-friendly photo or selfie from afar."
Lake Wanaka Tourism chief executive James Helmore said the tree had been one element of the town’s marketing campaign.
"We don’t encourage people to climb it," Mr Helmore said.
"It was a fencepost about 70-odd years ago and it grew from that."
He said photographing the tree was popular and had its own social media hashtag, #thatwanakatree, which was shared and viewed around the world.
