Nature lovers have embraced the cancellation of an art project that planned to colour trees blue.

The Blue Trees, an installation by Egypt-born artist Konstantin Dimopoulos, was supposed to take place over the weekend of Nov 7 and 8 at Dhoby Ghaut Green.

Volunteers were meant to paint the trunks and branches of about 20 trees with a blue water-based colourant to draw attention to the importance of trees and inspire conversation about deforestation.

Following protests by tree lovers, the National Parks Board withdrew its support and the event was cancelled. As the trees are on park land, NParks' permission was needed for the event to proceed.

Artist and urban design consultant Choo Meng Foo, 51, says he is elated by the news.

"I consider the colouring of the trees a violent act against nature," he says. "It would also encourage participants to disrespect nature and think of nature as being at man's disposal."

He was among the first people to raise his concerns about the project. He wrote two letters, including one to the National Arts Council, the event organiser.

Environmentalist Ria Tan, 54, who runs wildlife website Wildsingapore, also cheered the news of NParks' decision on her Facebook page.

She told Life: "Trees are not something lifeless like furniture that you can go and paint. They are part of a living web of life consisting of birds and other creatures.

"Each tree is home to tiny plants and animals living on and under its bark. Even if the colourant does not harm the tree, how do we ensure that the colourant does not harm other organisms?"

There has been disagreement on exactly how environmentally detrimental the blue paint is.

The National Arts Council said the colourant was developed by the artist for the installation and is "biologically and environmentally safe".

It has been used in 14 cities around the world, and the artist has provided testimonials by overseas tree organisations and certified arborists vouching for the safety of the colourant with regards to the trees, the surroundings and other life forms.

The colourant is not paint and consists mostly of water and 100 per cent organic material, "some of which can also be commonly found in children's face paint" and easily removed with water, the council said.

Nonetheless, NParks, which had initially given the green light for the project, decided to withdraw its support, as it wants to be "mindful of the sensitivities of the community towards our trees and the potential impact on insect biodiversity", says Ms Kalthom A. Latiff, deputy director of Arts & Heritage Parks at the agency.

The Blue Trees is a project under the National Arts Council's Arts in Your Neighbourhood programme. About 150 people had signed up to be volunteers in the tree-painting sessions.

When contacted yesterday, the art council's director for arts and community Chua Ai Liang says that while it respects NParks' latest position, it will "discuss this with the artist and hope to find a way to collaborate even as the project evolves from its original concept".

The artist, who was in town last week, has since left. His latest post on his Facebook page shows a photograph of the Blue Trees project in Germany.

Attempts to reach him were not successful.

The Blue Trees was launched in April 2011 at the Vancouver Biennale and has travelled to countries such as the United States, Britain and New Zealand.

It was named one of the Top 100 Activism Trends for ideas that changed the world in 2012.

Singapore is not the only place where some members of the public had expressed unhappiness with the installation.

In Squamish, a city in Canada, newspaper editor Christine Endicott wrote in the Squamish Chief in April this year that "Squamish is a unique place, where visitors come to escape to nature... It's baffling that we have a plan to alter (local) nature, based on the vision of an artist who does not live here".

Dr Shawn Lum, a botanist and a lecturer at the Asian School of the Environment at Nanyang Technological University, says painting the branches and trunks of the trees is unlikely to damage the tree as a whole.

Dr Lum, who is also the president of Nature Society Singapore, says: "It will likely hurt or even kill some of the tiny organisms living on the trees, but these organisms are likely to regenerate or return over time.

"The question we need to ask as a community is whether we want to risk this short-term impact on these micro-ecosystems to make an artistic statement, which may turn out to be a powerful one affecting many people."