Free for anyone
Tools and guides for consulting arborists
Written for the Australian standard and the way the work actually goes. No sign up, no email wall, nothing gated. If it saves you fifteen minutes on a report, it has done its job.
NRZ and SRZ calculator
Work out the Notional Root Zone and Structural Root Zone from your measurements, handle multi stemmed trees properly, and classify encroachment under AS 4970:2025. Runs in your browser, so it works on site with no reception.
AS 4970:2025: what actually changed
The TPZ now means something different, DBH is DSH, and encroachment has three defined tiers. Same maths, new words, and what to fix in your report templates before the next one goes out.
How to measure DSH properly
Slopes, forks, leans and buttress flare. Where the tape actually goes, why adding multi stem diameters together is wrong, and why a five percent measurement error moves the zone area by more than ten.
What councils actually check in an impact assessment
The five gaps that trigger a request for further information, what has to be in the report, the qualification most Victorian councils require, and a 2025 terminology trap worth avoiding.
Justifying an encroachment so it survives objection
The percentage tells you which conversation you are having, not whether the tree will be alright. Where the encroachment sits, when root investigation earns its cost, and how to structure the argument so it holds up.
Being written
- Recording assessments where there is no phone signal
- Choosing between retention and removal when the call is marginal