Mighty Tane Mahuta still stands strong, rumours of closure scotched

Kauri dieback, the effects shown above, has been infecting Waipoua Forest kauri since 2010 but Tane Mahuta is still safe.

There are no plans at this stage to close the walkway to the world's most famous kauri and other iconic trees in the Waipoua Forest.

Nor will Tane Mahuta be dead within a year, as claimed by some accusing Ministry for Primary Industries (MPI) of not acting quickly enough to protect New Zealand's biggest and oldest tree, known as the "Lord of the Forest".

According to a Lincoln University study, one in three kauri tested at all sites have shown signs of dieback disease (Phytophthora agathidicida), and the Waipoua Forest could be the worst affected of any place.

Dr Amanda Black, who works on the university's bio-protection research team, said on a recent radio newscast that Tane Mahuta would be ''infected'' within a year.

Some sources have incorrectly repeated her comment as ''dead'' within a year.

A Department of Conservation (DoC) spokesman said there is no evidence Tane Mahuta is infected and, if it were, because of its sheer size deterioration would occur over many years, not months.

However, DoC confirmed Tane Mahuta is ''at risk'' because of its proximity to infected kauri in a separate catchment. The catchment has been actively managed for many years; dieback was first discovered in the Waipoua in 2010.

More recently new lesion activity has been seen on another tree in that catchment, about 160m from Tane Mahuta. The spores of the kauri phytophthora are primarily spread through water and soil.

Contaminated and little-used tracks to other Waipoua kauri have been closed to the public but the Tane Mahuta boardwalk and cleaning station are of a standard unlikely to enable the disease to spread — as long as visitors comply, DoC said.

''The Tane Mahuta site is one of the most well-mitigated areas in the country and is protected by boardwalks, cleaning stations and ambassadors monitoring and managing for the risk. We are confident that the risk of further spread due to human vectors is low in this forest.''

When the disease settles in dirt at a kauri's base it creeps through the massive root system, then trunk and branches, sucking the life out over several years. There is no known remedy.

DoC is working with MPI, local iwi Te Roroa and other stakeholders to ensure the Waipoua risk is managed. Last week Te Roroa met with technical experts specialising in kauri dieback to discuss protection measures for the culturally significant site.

For the foreseeable future, the path ahead includes ongoing testing, monitoring and pig control, and visitor education.

Yesterday Black said one of the students at Lincoln University described in his thesis how P. agathidicida could be incubated in and spread from pine plantations and agricultural pasture by people, animals and machinery.

Black said earlier research this year showed P. agathidicida also infected other native plants, including tanekaha.