Health and Safety Tree Removal Reports – Dangerous Tree Assessment Newcastle

What Is a Health and Safety Tree Removal Report?

A health and safety tree removal report is the formal arborist assessment required to support a tree removal application where a tree presents a risk to people, property or infrastructure.

Under Newcastle City Council's DCP 2023 and the Urban Forest Technical Manual, removal on health and safety grounds must address the Risk Assessment Test in Part A Section 3.4.4. This test requires the arborist to demonstrate:

• The tree presents a structural defect or condition that creates unacceptable risk
• The likelihood of failure is established, not assumed from appearance alone
• Targets have been identified including people, property, accessways or structures in the failure zone
• The consequence of failure is assessed, not just the probability
• Pruning or risk mitigation cannot reasonably manage the risk to an acceptable level
• Removal is the most appropriate response given the evidence

Quick Assessment Guide

A report that simply states a tree looks dangerous will not satisfy Newcastle City Council. The Risk Assessment Test requires structured evidence of structural condition, failure likelihood and consequence, presented by a suitably qualified AQF Level 5 arborist.

When Do You Need a Health and Safety Tree Removal Report?

A health and safety report is typically required where:

• A tree has structural defects including decay, deadwood, included bark, root plate damage or fungal activity
• A tree has suffered storm damage affecting structural integrity
• A tree is leaning with evidence of root plate movement or soil heave
• A tree is in significant decline and posing risk to adjacent structures or people
• A tree has a history of branch failure over a target including accessways, playgrounds, car parks or dwellings
• A tree's root system is compromised by construction, drought, soil compaction or disease
• Council or an insurer requires independent structural risk documentation
• A tree has been flagged by a building or insurance assessment as requiring arborist assessment

Not all unhealthy or unattractive trees qualify for removal on health and safety grounds. The Risk Assessment Test is specific. Risk must be assessed against identifiable targets and found to be unacceptable before removal will be supported.

Our Structural Risk Assessment Method

Every health and safety report we prepare uses a systematic approach to tree risk assessment, consistent with QTRA (Quantitative Tree Risk Assessment) methodology and the Urban Forest Technical Manual Part A Section 3.4.4 Risk Assessment Test.

Structural Condition Assessment

We assess the tree's above-ground structure and below-ground root system for all indicators of structural compromise:

• Trunk defects including cavities, decay columns, included bark, co-dominant stems and cracks
• Crown condition including deadwood distribution, dieback pattern, foliage density and crown asymmetry
• Root zone condition including root plate stability, soil heave and exposed or damaged surface roots
• Evidence of past failure including old wound wood, previous branch loss sites and callus growth
• Fungal activity including fruiting bodies, bracket fungi and mycelial mats, indicators of internal decay

Common Structural Defects We Assess

The following defects are the most common indicators of structural compromise assessed in health and safety reports across Newcastle:

• Basal cavities, hollow base of trunk reducing structural cross-section
• Included bark, bark trapped between co-dominant stems creating a weak union prone to splitting
• Co-dominant stems, two stems of equal size competing with included bark at the union
• Root plate instability, soil heave, leaning with root movement and exposed or damaged structural roots
• Fungal decay, bracket fungi, fruiting bodies or mycelial mats indicating internal wood decay
• Dead scaffold limbs, large deadwood over targets liable to failure without warning
• Crown dieback, progressive decline indicating systemic vascular or root system failure
• Previous failure sites, old wound wood indicating past branch loss and potential further failure
• Construction damage, root severance, soil compaction or grade changes within the TPZ

Each defect type has a specific failure mechanism, a specific likelihood of failure profile and a specific mitigation or removal response. Our reports document each defect present, its significance and its contribution to the overall risk rating.

Advanced Diagnostic Testing – Resistograph and AirSpade

Where visual assessment alone cannot confirm the extent of internal decay or root compromise, we use in-house advanced diagnostic tools.

Resistograph decay testing is a micro-drill probe that measures wood density through the trunk, producing a resistance graph that maps decay columns, cavities and sound wood. Non-destructive. Provides objective internal evidence of structural integrity that visual assessment cannot confirm alone.

AirSpade root investigation uses compressed air excavation exposing root architecture without cutting or compacting. Used where root plate stability or soil condition is in question and visual assessment of the below-ground zone is required.

These diagnostic tools are in-house. We do not subcontract. Results are documented in the report as objective evidence of structural condition.

Likelihood of Failure Assessment

We assess the probability of failure under foreseeable conditions including wind loading, seasonal stress, drought and storm events, using structural evidence, not assumption.

Factors assessed include:

• Defect type and severity, which defects most increase failure risk
• Wood strength remaining at the point of maximum stress
• Loading including canopy size, crown asymmetry and wind exposure of the site
• Structural configuration including stem angle, branch attachment and root plate geometry

Target Assessment and Consequence Rating

A tree's risk rating depends on what is in the failure zone and how often people or structures are present. We identify:

• Primary targets including permanent structures, accessways, car parks, dwellings and public space
• Occupancy, how often people are present in the target zone
• Secondary targets including adjacent trees, services, fencing and vehicles

A tree presenting a high likelihood of failure over an unoccupied paddock is a different risk from the same tree over a school access path. Target assessment is what separates a defensible report from a generic opinion.

Risk Mitigation Assessment - Is Removal the Only Option?

Newcastle City Council applies a retention-first principle. Removal must be justified, not assumed. Our report documents whether risk mitigation alternatives can reduce the risk to an acceptable level:

• Crown reduction, reducing canopy weight and wind loading
• Deadwood removal, eliminating the primary failure hazard
• Target modification, relocating assets out of the failure zone
• Cabling or propping where structurally appropriate

Only where mitigation cannot reduce the risk to an acceptable level is removal the supported outcome.

QTRA – Quantitative Tree Risk Assessment

Our lead arborists at Newcastle Tree Permit Services hold certifications that go beyond the standard AQF Level 5 qualification. Robert de Jong and Alexander de Jong are both certified in QTRA, Quantitative Tree Risk Assessment, an internationally recognised, systematic methodology for tree risk quantification.

QTRA uses a mathematical framework to express tree risk as a probability, combining likelihood of failure, likelihood of impact and consequence of failure into a quantified risk output. This methodology is increasingly expected on:

• Complex health and safety removal applications where risk justification is disputed
• Insurance matters where structural risk must be quantified for claims purposes
• Legal proceedings where tree risk must be expressed as expert evidence
• High-profile targets including public open space, schools, heritage assets and commercial properties

Most arborist practices in Newcastle cannot offer QTRA-certified risk assessment. Where applicable, our reports also reference TRAQ (Tree Risk Assessment Qualification) frameworks, the ISA standard widely used in professional tree risk documentation for legal and insurance contexts.

Where a removal application involves a high-profile target or is likely to be contested, QTRA methodology provides a level of rigour that standard visual assessment cannot match.

Why Property Owners and Insurers Choose Arbor Express

• AQF Level 5 Consulting Arborists with QTRA-certified structural risk assessment capability
• Resistograph decay testing and AirSpade root investigation in-house, objective evidence, not opinion alone
• Urban Forest Technical Manual Part A Section 3.4.4 Risk Assessment Test addressed with evidence
• Insurance-ready reports, structured to satisfy insurer requirements and support claims
• Local Newcastle arborists, we know this Council, these trees and these suburbs
• DCP 2023 compliant, current rules applied correctly
• Fast-track available, most reports within 3-4 business days

Not all arborists operating in Newcastle hold AQF Level 5 qualifications. Verify credentials before engaging anyone. Every Arbor Express arborist meets or exceeds the Council standard.