A new round of aerial checks for kauri dieback disease is under way over the Coromandel Peninsula, Hauraki and central Waikato.
It follows a series of flights last year which targeted western areas of the region.
The latest surveys, which began on Monday and are expected to continue until February 28 for the Waikato Regional Council, will be using a fixed wing plane.
Biosecurity officer Kim Parker said kauri dieback had already been found on the Coromandel Peninsula at Hukarahi and within the Whangapoua Forest.
"This latest round of checks is about casting our net wider, from Hamilton to the Hunuas across to the Coromandel, and down to the Kaimais.
"On such a large landscape kauri dieback symptoms are more easily spotted from the air, so an aerial survey is the most efficient way for us to check the state of health of stands of kauri. It's crucial that we stop the spread of this crippling disease which attacks our amazing kauri trees."
There is no confirmed presence of kauri dieback in Hauraki district but there have only been limited checks so far.
Kauri dieback is caused by a microscopic fungus-like organism called Phytophthora agathidicida.
The disease infects kauri roots and damages the tissues that carry nutrients and water within the tree, basically starving the tree to death.
Other kauri dieback symptoms include bleeding around the roots and lower trunk.
It kills kauri of all sizes, from the smallest of seedlings to the mightiest of giants.
Once a tree has the disease there is no cure.
The latest surveys will be carried out for the council as part of the National Kauri Dieback programme, and involve co-operation with the Ministry for Primary Industries, the Department of Conservation, Bay of Plenty Regional Council, and Auckland Council.
A kauri dieback expert will be looking for yellowing leaves, canopy thinning and/ or dead branches.
The survey will be carried out over about five days from late-January to the end of February. The exact dates will depend on suitable weather conditions.
People in the surveyed areas may notice a plane flying in a grid.
Soil movement is the big risk factor for spreading the disease and people are encouraged to follow the prevention measures at www.kauridieback.co.nz.
This includes the following info:
Prevention: What can I do to save our kauri forests?
Without any treatment or control tools, the only way we can save our kauri forests is to contain the disease in its current locations and stop the spread into healthy areas. When around kauri:
• Make sure shoes, tyres and equipment are cleaned to remove all visible soil and plant material before AND after visiting kauri forest
• Please use cleaning stations installed on major tracks: scrub to remove all soil and spray with disinfectant.
• Stay on the track and off kauri roots
• Keep dogs on a leash at all times.
We all can help - tourists, hunters, trappers, trampers, runners, bikers, walkers. We all need to make it happen, rather than hope "someone else" will do it.
- Any questions about the survey can be directed to 0800 800 401. Information on kauri dieback is also available at www.kauridieback.co.nz.