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Kauri dieback creeping towards Tane Mahuta

Kauri dieback disease has been confirmed in a young tree just 60 metres from the iconic New Zealand Tane Mahuta. Source: Stuff NZ

The discovery means the 100% fatal fungal disease could already be well within the spread of the giant tree’s root system in Waipoua Forest, about 45 kilometres north of Dargaville. 

Tāne Mahuta – Northland’s ancient and iconic kauri tree is estimated to be between 1250 and 2500 years old.

Iwi and its science partners confirmed the infection of the “ricket”, or non-mature tree, which sits in clear line of sight to Tāne Mahuta, several weeks ago.

The Department of Conservation (DoC) was informed but had “sat on the information”, Patuawa said. 

Te Roroa science advisor Taoho Patuawa wants urgent soil and root testing in the vicinity of Tāne Mahuta (Lord of the Forest) – New Zealand’s oldest and most revered “Rangatira” tree to establish whether the giant is infected or in immediate danger of becoming infected. 

The iwi is heavily critical of DoC for refusing to carry out any “on the ground testing” of soil or root samples around Tāne Mahuta, despite knowing of the danger for years.

Only aerial surveys had been done, the latest of which, conducted by the Ministry for Primary Industries last summer, found 200 new spots where infection was suspected. 

Patuawa said a contingency plan for Tāne Mahuta and its immediate surrounds, ordered by former Conservation Minister Maggie Barry in 2013 and written by DoC staff, was ignored. 

Mr Patuawa says the 100% fatal fungal disease could already be within the spread of Tāne Mahuta’s root system.

While widespread surveys, including ground testing, were carried out in Auckland’s infected Waitakere Ranges, DoC had refused to do so in the Waipoua forest despite years of urging, he said. 

Te Roroa wants to go ahead with its own testing to see whether kauri dieback, also known as phytopthera agathadisida, is in Tāne Mahuta’s root system. It asked DoC for resourcing for the iwi’s own experts to do the work, but “they’ve offered the bare minimum of what we’ve been asking for”, Mr Patuawa said. 

DoC’s Northern North Island director of operations Sue Reed-Thomas said the department would be open to funding the iwi’s experts “but we’ve got to see the plan first”. 

She defended DoC’s handling of kauri dieback in Waipoua. 

“We have done as much as we can in the absence of the science to prove how to cure or how to stop the spread of the disease.” 

Ms Reed-Thomas said she had received “verbal advice” from Te Roroa that the young tree near Tāne Mahuta was infected.

The department had not asked to see a written report or the specific soil samples that confirmed the infection. The contingency plan had not resulted in soil or root sampling, she said. Taking soil samples risked spreading the disease. 

Winter was an unsuitable time to test for kauri dieback, and an agreement between DoC and iwi should be finalised by the time it was safe to do so. 

Ms Reed-Thomas denied there had been a breakdown in the relationship between Te Roroa and DoC at regional level. 

“That would be a surprise to me,” she said. 

Dr Amanda Black, from the Bioprotection Research Centre at Lincoln University, said the pathogen that caused kauri dieback could “sniff out kauri roots and move towards them through water, all by itself”.

Dr Black said building better boardwalks, tracks and cleaning stations would not be enough to save the iconic kauri, and other forest giants like it.

Kauri dieback had been found 200m from the stand of giants known as the Four Sisters. There was a growing consensus among the scientific community that the Waipoua forest, including the popular kauri walking tracks and access to Tāne Mahuta, should be closed immediately. 

Te Rorora was considering placing a “rahui” – a prohibition to enter – on the forest in its capacity as manua whenua. A similar rahui placed on the Waitakere Ranges last December was the trigger for the ranges to be closed to the public, in an attempt to stop the spread of the disease.

Tāne Mahuta (Lord of the Forest) is a popular tourist attraction in Waipoua Forest, about 45 kilometres north of Dargaville.

Former head of Biosecurity for Auckland Council, Jack Craw, said DoC and the Ministry for Primary Industries had fallen well behind with their response to the situation at Waipoua and the nearby Trounson Kauri Park, which was now a “graveyard.” 

“This is the most serious thing I’ve ever seen. It’s like HIV and Ebola rolled into one,” he said. He agreed that the forest should be closed as soon as possible. 

“New Zealand will have to get used to staying away from its kauri. To keep it alive we’ve got to leave it alone.” 

Mr Craw said that as well as closing the Waitakere Ranges, Auckland Council had contracted pig hunters to cull wild pigs in the region. He was critical of MPI for refusing to do the same at Waipoua.

Pigs are suspected to be spreading the disease as they move around the forest. 

Ms Reed-Thomas said DoC was open to the idea of a pig culling program, but questioned the logic of closing the forest altogether now the department had built raised boardwalks, improved tracks and built new footwear cleaning stations. 

“I would ask, what else would be achieved by closing the forest? The crucial thing is to help people understand the risk they create if they don’t follow the rules.” 

Kauri dieback is spread through soil movement. Increasing numbers of scientists have publicly criticised MPI’s handling of the kauri bio-crisis. Many agree that after a good start in 2009, officials had “dropped the ball” in the past few years.  

Mr Craw said MPI should immediately relinquish control of the response to a community charitable trust, which would consult with individual iwi. 

“This shouldn’t be driven by central government when Maori are the ones that know better.” 

Mr Craw, the former head of biosecurity at Auckland Council, says the spread of the disease is the worst biosecurity incident he has encountered in his 40 years in the industry.