Kauri existence under threat from dieback disease

UNDER THREAT: With no known cure kauri dieback has the potential to wipe out New Zealand kauri if action isn't taken to stop it.

Kauri dieback disease is killing kauri trees throughout Northland, Auckland and the Coromandel.

First discovered in the Waitakere Ranges west of Auckland in 2006 and formally identified as a new disease to science in 2008, this disease was soon reported in other areas of both public and private land.

This fungus-like disease is soil borne and comes from the same group of species that causes potato blight, which lead to the Irish potato famine in 1845. With no known cure kauri dieback has the potential to wipe out New Zealand kauri if action isn't taken to stop it.

Microscopic spores in the soil infect kauri roots and damage the tissues that carry nutrients within the tree. Infected trees show a range of symptoms including yellowing, loss of leaves, dead branches and lesions that bleed gum at the base of the trunk.

Nearly all infected kauri die. In the past 10 years, kauri dieback has killed thousands of kauri in New Zealand. Scientists are currently working to find control tools for this disease but there is no known treatment at this time.

However, it's not all bad news. With proper measures kauri dieback can be contained where it is and areas of healthy kauri preserved for generations to come.

At this stage, the disease has not been detected in many areas of Northland forests, the Hunua Ranges and Hauraki Gulf Islands (excluding Great Barrier).

Many farms with bush remnants throughout Waikato, Auckland and Northland are also still healthy and can act as safe havens for the future of our kauri.

Because kauri dieback spreads through soil movement, anything that can move soil can spread the disease. To prevent this spread we all need to ensure footwear and gear are cleaned before and after visiting kauri forests and stick to the tracks and off kauri roots.

On-farm machinery, livestock and feral animals can easily spread kauri dieback within and between kauri forests. To protect your kauri, avoid movement of livestock through kauri forest remnants and ensure machinery is cleaned before and after working in kauri areas. Ideally, such remnants should be fenced-off with good stock-proof fencing. Many local councils have funding assistance available for fencing off bush blocks.

If you have concerns about kauri health, on public or private land -- contact 0800 NZ KAURI or visit www.kauridieback.co.nz for more information.