New Zealand / Environment

Northland councillor fears Kauri could become extinct on Crown land

10:16 am on 1 October 2020

A Northland councillor is predicting kauri will be extinct on Crown land in the next 30 years because the government is not doing enough to control kauri dieback across the upper North Island - but local iwi strongly disagree with that assessment.

Kauri in Waipoua Forest in Northland. Photo: RNZ / Jackson Payne

Northland Regional Council councillor Jack Craw is the former biosecurity manager for Auckland Council.

He has accused the Ministry for Primary Industries and the Department of Conservation of dropping the ball on managing the disease.

"We still haven't completed surveillance of where the disease is. It's been 12 years now and we still don't know in Northland where the disease is, aside from a couple of small spots."

He said there are no accurate figures either on how many trees have died from the disease.

"In Northland, I'd say Waipoua Forest is probably 30 to 40 percent dead, Trousen [Forest] is about 70 percent dead and we're heading for extinction of kauri on Crown land within the next 30 years."

Te Roroa iwi was the kaitiaki for Waipoua Forest which is home to iconic giant kauri, including Tāne Mahuta and Te Matua Ngahere.

Snow Tane says the iwi is doing everything in its power to prevent the spread of kauri dieback. Photo: RNZ / Lois Williams

The iwi's general manager, Snow Tane, disputed Jack Craw's estimations.

He said they needed to be 'ground-truthed' - or verified with on-the-ground observations.

Craw's estimations did not match what he saw during an aerial observation two years ago of the forest.

"That may have been the case closer to the main road, because the most infected areas are those closer to State Highway 1," he said.

Tane said the iwi is doing everything in its power to prevent the spread of the disease.

This includes spending up to $100,000 on mitigation measures and working with the Ministry for Primary Industries and DOC to develop new plans.

DOC national operations manager for kauri Alan McKenzie said the Waipoua Forest was of particular concern, but the agency was working hard to fight the disease and protect kauri across the country.

This included spending $20 million to upgrade tracks and set up hygiene stations, along with soil sample testing.

So far this year, soil samples by the department revealed 46 positive results for kauri dieback out of 132 tests.

There was one positive result out of 75 tests in 2019, and 19 positive results out of 74 tests in 2018.

McKenzie said there is more that can be done and they are ready to act on any new scientific discoveries that will help manage the disease.

In a statement, Ministry for Primary Industries said significant work, costing $90 million has been underway to fight the disease since 2009.

This included research, on the ground protection, and aerial surveillance of more than 3m hectares of land.

Meanwhile, Auckland Council kauri dieback team manager Lisa Tolich said it was difficult to determine how many trees in the region are infected as it could take years for trees to show symptoms.

The focus was on areas where the disease had not yet spread to, such as the Hunua Ranges and Waiheke Island.

"We focus on identifying sites [and] areas where the pathogen is in the soil, but also symptoms of the disease. It's like a snapshot in a point of time."

She said ongoing monitoring was key to detecting any spread of the disease and the council currently tested every five years.

A council targeted rate had gathered $105m over 10 years, which had allowed the council to expand its monitoring system.

In addition, the council had spent $24m in last two years upgrading tracks, conducting research and monitoring the forests in the region.

People were urged to stick to marked tracks, use hygiene stations to clean footwear and follow official instructions when out in kauri forests this summer season.