Tanekaha affected by kauri dieback, study suggests

Friday, 23 February 2018

Kauri dieback may threaten other native plants, including tanekaha.

Auckland University research looked at whether the microscopic fungus might have a wider impact than just on kauri trees.

'I think we've proved that other species are affected,' associate professor Bruce Burns said.

'We don't know how they are affected, and we don't know the full range of the hosts that could be affected by kauri dieback, but I think we can say that it doesn't just infect kauri.'

**READ MORE:

* Council moves to close Waitākere Ranges and Hunua kauri areas

* Auckland Council votes against full closure of Waitākere Ranges

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In the research, Masters student Jessica Ryder identified differences in the makeup of ecosystems around infected and healthy kauri groves in the Waitākere Ranges.

She then tested the susceptibility of these plants' leaves by infecting them with kauri dieback disease in petri dishes – and found lesions grew on six different species. 

The disease was then re-isolated from the leaves of two of them – tanekaha and rewarewa.

Ryder infected seedlings of these two native trees with kauri dieback disease.

After nine weeks, the young tanekaha showed signs of dieback above and below the ground, although the rewarewa did not.

Burns said the study showed kauri dieback disease was probably not only found in kauri.

'There are other species in that plant community that will be affected.'

Burns said the study also suggested kauri grass could carry the disease even though it did not show symptoms.

'It could act as a reservoir in the community to keep that dieback organism going.'

The Waitākere Ranges are set to be off limits to the public from May as Auckland Council considered tougher measures to combat kauri dieback disease.

Kauri dieback disease is a fungus mainly spread on human shoes.

It slowly kills all kauri it infects, and there is currently no cure.