Why I Use TRAQ for Tree Risk (and Why It Serves You Best)

Last winter I assessed a leaning sycamore over a village footpath used twice daily on the school run. The stem was sound, but two long laterals carried too much end-weight. Using the TRAQ tree risk assessment framework, the Likelihood of Failure was Possible and the Likelihood of Impact was High—a Moderate risk. We reduced the lever arms, removed deadwood, and set a six-month review. Safer route, canopy kept, sensible cost. That’s why I use TRAQ.

Why TRAQ?

I base my reports on the ISA’s Tree Risk Assessment Qualification (TRAQ) because it’s structured, consistent, and defensible—easy to explain to clients, neighbours, insurers and courts. Learn more at the ISA/TRAQ, the Arboricultural Association, the National Tree Safety Group (NTSG) and HSE. Where works are specified, I align with BS 3998 principles (see the Arboricultural Association).

What TRAQ gets right

• Trusted and replicable: standard definitions and matrices mean different competent assessors should reach comparable outcomes.
• Objective and proportionate: real-world targets (people, property, footpaths, roads, overhead wires, buildings) are weighed alongside tree condition.
• Scalable: works for a single tree or a large estate, and plays nicely with advanced diagnostics (e.g., decay detection) when needed.
• Aligned with UK guidance: consistent with NTSG’s proportionate risk management and BS 3998 good practice.

How TRAQ works (short version)

Timeframe: normally 12 months (I’ll state if a different horizon is appropriate for species/site use).

1. Inspect the tree: species, defects, history, load, site context.
2. Identify targets: who/what could be hit (people, vehicles, structures, utilities).
3. Score Likelihood of Failure (LOF): Imminent / Probable / Possible / Improbable.
4. Score Likelihood of Impact (LOI): High / Medium / Low / Very Low.
5. Combine to LOFI: how likely failure and impact are together.
6. Consider Consequences: Severe / Significant / Minor / Negligible.
7. Risk Rating: Extreme / High / Moderate / Low → drives recommendations.

Quick glossary (plain English)

• LOF: chance a tree/part fails in the timeframe (Imminent, Probable, Possible, Improbable).
• LOI: chance a target is present at impact (High, Medium, Low, Very Low).
• LOFI: combined likelihood (from Unlikely to Very Likely).
• Consequences: severity if impact occurs (Negligible → Severe).
• Risk Rating: overall level (Low → Extreme) used to prioritise action.

Matrices at a glance

LOF × LOI → LOFI

‍

LOFI × Consequences → Risk Rating

What you’ll get from me

• Clear priorities: which trees need action first—and why.
• Proportionate works: monitor, prune, reduce, remove only where justified; retain canopy wherever sensible.
• Documented assumptions: access limits, target occupancy, method reasoning (auditable for duty of care).
• Re-inspection plan: because trees and sites change (storms, decay progression, groundworks).

Good to know: TRAQ is a structured, qualitative method grounded in field observation. It guides reasonable decisions; it doesn’t promise zero risk. Recommendations reflect your risk tolerance and relevant UK guidance (NTSG, BS 3998) and are made in good faith at the time of inspection.

Want a TRAQ-based tree survey or a portfolio plan?

I’ll prepare a contractor-ready report (map, priorities, schedules) with plain-English specifications and timeframes, aligned with TRAQ, BS 3998, NTSG, and HSE expectations.