Trees are one of the great joys of a Kiwi property — they provide shade, privacy, and character. But when they need attention, it can be tempting to reach for the ladder and chainsaw yourself. Knowing where the line sits between a safe DIY job and one that needs a qualified arborist could save you from serious injury, property damage, or even legal trouble.
What Can a Homeowner Safely Do?
There are plenty of tree tasks well within the reach of a careful, capable homeowner:
- Light pruning of small shrubs and ornamental trees you can reach from the ground
- Removing small branches (generally under about 50 mm diameter) with hand pruners or loppers
- Clearing fallen branches after a storm, provided they are not tangled in power lines or structures
- Planting and mulching around established trees
- Watering and basic fertilising to support tree health
If you can do the work safely with both feet on the ground and without power tools, you're likely in DIY territory.
When the Job Calls for a Qualified Arborist
The moment a job involves height, large branches, power tools, or a tree that is structurally compromised, the risk profile changes dramatically. Here's when you should pick up the phone:
The Tree Is Large or Overhanging Structures
Large trees — especially those overhanging your house, a neighbour's property, fences, or driveways — require careful rigging and sectional removal techniques. A branch dropped in the wrong direction can cause tens of thousands of dollars in damage or, worse, injure someone. A qualified arborist has the training, equipment, and insurance to manage this safely.
The Tree Is Near Power Lines
This is non-negotiable. Working near power lines is extremely dangerous and in many cases legally restricted. In New Zealand, only approved line-clearance arborists are permitted to work within certain distances of live conductors. Contact your lines company before any work begins — they may carry out or oversee the work themselves. WorkSafe NZ has clear guidance on working safely near electricity.
The Tree Appears Diseased, Dead, or Structurally Unsound
A dead or dying tree can drop branches without warning. Signs to watch for include fungal growth at the base, significant dead wood in the canopy, cracks in the trunk, or leaning that has developed suddenly. A qualified arborist can assess whether the tree is a hazard tree and recommend removal or remediation before it becomes an emergency.
You Need to Use a Chainsaw at Height
Using a chainsaw on the ground already demands respect and proper training. Using one while climbing or on a ladder multiplies the risk enormously. Arborists who climb trees are trained in aerial tree work and use specialist climbing equipment and harnesses. This is not a skill to improvise.
The Tree Is Protected or Subject to a Resource Consent
Many councils across New Zealand have Notable Tree schedules or rules in their district plans that restrict or prohibit work on certain trees without consent. Removing or significantly pruning a protected tree without permission can result in substantial fines. Check with your local council before starting any significant work. An experienced arborist will know the local rules and can help you navigate the consent process.
Neighbour or Boundary Disputes
If a tree sits on or near a boundary, or if branches or roots are encroaching on a neighbour's property, getting a professional assessment in writing can be invaluable. An arborist's report carries weight if a dispute escalates.
DIY vs Professional: A Quick Comparison
| Task | DIY OK? | Call an Arborist? |
|---|---|---|
| Pruning small shrubs from ground level | ✅ Yes | Not needed |
| Removing branches up to ~50 mm diameter | ✅ With care | If in doubt |
| Pruning large branches or canopy work | ❌ No | ✅ Yes |
| Any work near power lines | ❌ No | ✅ Yes (approved) |
| Felling a tree of any significant size | ❌ No | ✅ Yes |
| Assessing a potentially hazardous tree | ❌ No | ✅ Yes |
| Removing a protected/notable tree | ❌ No | ✅ Yes + council consent |
| Stump grinding | ❌ Generally no | ✅ Yes |
What Qualifications Should an Arborist Have?
Look for an arborist with a New Zealand Certificate in Arboriculture or equivalent, and ideally membership with the New Zealand Arboricultural Association (NZAA). Always confirm they hold current public liability insurance and, for any aerial work, appropriate personal accident cover. BRANZ and industry bodies recommend getting at least two quotes and checking references for significant tree work.
Safety First — Always
Even for simple DIY pruning, wear appropriate PPE: safety glasses, gloves, sturdy footwear, and a helmet if there's any risk of falling debris. Never work alone on anything involving a ladder or power tools. If there is any doubt about a tree's stability or the safety of a job, stop and call a professional. No tree is worth a trip to the emergency department.
When to Call a Professional
Call a qualified arborist any time a job involves working at height, using a chainsaw, trees near power lines or structures, potentially hazardous or protected trees, or when you simply aren't confident in your own assessment. A professional arborist will also carry the right insurance — protecting you if something goes wrong on your property. You can find qualified, local arborists on tradedirectory.co.nz.