Gum bleeding at the base
Sticky, pale resin weeping from the lower trunk or the root collar, often near ground level. This is the classic early indicator and the one most people spot first.
West Auckland Kauri Dieback
Assessment, hygiene advice and careful removal — from arborists who work around kauri every week.
What Causes Kauri Dieback
The culprit is Phytophthora agathidicida, a microscopic soil-borne organism. It is a water mould rather than a true fungus, though it behaves much like one. It attacks the fine feeder roots and the collar of the tree, which slowly cuts off the tree's ability to draw up water and nutrients. What you see in the canopy is the symptom; the damage is happening underground.
It travels in soil and water, not through the air. A teaspoon of infected dirt on a boot, a bike tyre, a wheelbarrow or a digger bucket is enough to introduce it to a clean site, and it also moves in surface water running downhill through a root zone. That is why so much of the response is about keeping soil where it is rather than treating the tree.
There is currently no cure. Phosphite treatment can slow the disease and buy an infected tree time, but it does not clear the pathogen from the soil, and once a kauri is significantly affected the decline tends to be one-way.
Signs Your Kauri Tree May Be Infected
Symptoms come on slowly, and several of them can have other explanations — drought stress and root damage look similar from a distance. Any of the following is worth getting looked at properly rather than watched for another season.
Yellowing foliage
Leaves losing their deep green and turning a dull yellow, usually across the whole canopy rather than in one patch. Healthy kauri hold their colour year round.
Thinning canopy
The crown gradually opening up so you can see more sky through it than you used to. Compare against a neighbouring kauri if you have one to judge it against.
Dead branches in the crown
Bare limbs appearing in the upper canopy while the rest of the tree still has leaves. Progressive dieback from the top down is a bad sign in a kauri.
Lesions on the lower trunk
Dark, sunken patches in the bark around the base, sometimes with resin flowing from them. These are worth photographing so change can be tracked over time.
Neighbouring trees declining
The disease travels in soil and surface water, so a kauri showing symptoms uphill or next door raises the risk to yours considerably.
When Tree Removal Is the Right Call
Removing a kauri is a last resort, and it should never be the first suggestion you hear. A tree in early decline may hold on for years, and standing kauri — even unwell ones — still provide habitat and shade, and still hold a bank of soil together on a steep section.
The point at which removal becomes the right answer is usually about safety rather than the disease itself. A kauri that has lost enough root function becomes unstable, and a large one falling onto a house, a driveway or a neighbouring property is a very different problem. Extensive crown death, significant trunk lesions, or a tree that has begun to lean are the sorts of findings that shift the conversation.
It is also worth knowing that kauri are protected in Auckland, and removal generally requires resource consent from the council regardless of the tree's health. That process takes time, and it is not something to start the week you want the tree gone. We can tell you whether your situation is likely to need consent and what the council will want to see, though you should always confirm the current requirements with Auckland Council directly before committing to anything.
Protecting Healthy Kauri on Your Property
If your kauri is still in good shape, the job is to keep it that way — and most of that comes down to leaving the ground around it alone. Kauri are far more sensitive to root disturbance than most trees, and a lot of the damage we see was done by well-meant landscaping rather than by disease.
Practically, that means no trenching, digging or building within the root zone, no piling soil or mulch against the trunk, and no driving or parking under the canopy. A generous layer of coarse leaf litter left where it falls does more good than tidying it away. If you are planning a deck, a shed, a driveway or a drainage run anywhere near a kauri, get advice before the excavator arrives rather than after.
It is also worth simply looking at the tree twice a year and photographing the base from the same spot each time. Change is gradual enough that you will not notice it day to day, but a set of photos two years apart makes it obvious.
Calling a Qualified Arborist in West Auckland
Kauri are not a tree to hand to a general contractor. The hygiene requirements alone rule out anyone turning up with the same unwashed gear they used on the last three jobs, and the consent side has real consequences — unauthorised work on a protected tree can attract serious penalties on top of whatever the removal costs.
Our arborists are qualified, fully insured, and work around kauri regularly across the Waitākere foothills, Titirangi, Laingholm and the wider west. An assessment visit is free. You get an honest read on what the tree is doing, what is realistic to do about it, and whether you need to involve the council — and if the answer is that the tree is fine and you should leave it alone, that is what we will tell you.
Get Your Kauri Assessed
If something about your kauri has changed, the earlier it is looked at the more options you have. Book a free assessment and we will give you a straight read on where the tree stands.