Most pruning mistakes happen before the saw comes out. Someone notices a branch brushing the gutter, grabs a loppers and starts cutting, and only later realises the tree was already stressed, the branch was holding up half the canopy, or the cut has opened a wound that will never close properly.
This guide walks through what to look at, in roughly the order a careful arborist would, so you can decide whether a job is a quick tidy-up you can handle or something that needs a professional and possibly a conversation with the council.
Start from the street, not the ladder
Stand back far enough to see the whole tree, ideally from two or three sides. You are looking at overall shape and balance.
- Lean: Is the trunk leaning, and if so, is the soil on the opposite side cracked or heaved? An old, settled lean is usually fine. A new lean after heavy rain is a warning sign.
- Canopy density: Compare this year’s foliage with photos from previous summers if you have them. A thinning crown often signals root trouble rather than a need for pruning.
- Weight distribution: A tree that has grown heavily towards the house or towards light gaps may already be lopsided. Removing more from the light side can make things worse.
Note any deadwood at this stage. Dead branches are usually greyer, have no buds or leaves in the growing season, and often have bark peeling away.
Read the trunk and the base
Move in close and work your way around the trunk from the ground up. The root flare, where the trunk widens into the soil, should be visible. Mulch piled against it can rot the bark.
Look for mushrooms or bracket fungi at the base or on the trunk. Not every fungus is a problem, but some indicate internal decay that can weaken the tree significantly. Cavities, oozing sap, cracks running vertically down the bark and areas where the bark sounds hollow when tapped with a knuckle are all worth photographing and showing to an arborist.
Pay attention to forks. Two stems of similar size growing from the same point, with bark pinched between them, form what is called included bark. These unions are weaker than a clean branch attachment and are a common failure point in storms.
Understand how branches attach
Every branch joins the trunk at a slightly swollen collar. Healthy cuts are made just outside this collar, never flush with the trunk and never leaving a long stub. The collar seals the wound over the following seasons.
Before you cut, trace each branch you plan to remove back to where it starts. Ask yourself:
- How large is it at the base? Branches thicker than your wrist leave wounds that close slowly and may let decay in.
- What else will move once it is gone? A branch can be bracing or shading another one, and removing it changes how wind hits the canopy.
- Where will it fall? Plan for the weight, not just the length. A three-metre branch of green pÅhutukawa can weigh more than you expect.
As a rough rule, avoid removing more than about a quarter of a healthy tree’s live canopy in one year. Stressed, old or recently disturbed trees often tolerate far less.
Check the timing and the rules
Season matters. Many deciduous trees are best pruned in late winter, roughly July to August in New Zealand, when the structure is easy to see and the tree is dormant. Evergreens and natives vary. Pruning in a hot, dry spell in January or February adds stress, and cutting stone fruit in wet autumn weather can invite silver leaf infection.
Rules matter too. Some trees are protected by district plan schedules, and work near power lines has its own requirements. Tauranga homeowners can find tree-related rules and contacts on the Tauranga City Council website, and other councils have equivalent pages. If a tree is notable, on a reserve boundary or within a heritage area, check before doing anything beyond minor deadwood removal.
It is also worth knowing what to do if a storm does the pruning for you. A practical companion read is this guide on dealing with fallen trees and floodwater after a storm.
Frequently asked questions
How do I know if a branch is dead or just dormant? Scratch a small patch of bark with a fingernail. Green or moist tissue underneath means the branch is alive. Brown, dry tissue and brittle twigs that snap cleanly suggest it is dead. Deciduous trees in winter can look lifeless, so check buds as well.
Should I paint or seal pruning cuts? Generally not. Current practice favours clean cuts outside the branch collar and letting the tree seal the wound naturally. Wound paints can trap moisture and may slow the process.
When should I stop and bring in an arborist? If the work needs a ladder higher than a couple of metres, involves branches over a roof, power line or driveway, or if you have spotted fungi, cracks or a new lean, it is time for a professional assessment. The cost of a site visit is usually small compared with the damage a falling limb can do.