Understanding and managing the risk associated with trees is a critical component of responsible land and asset management. At Parkes Arbor Consultancy, we provide comprehensive, technically robust tree risk assessments to help our clients make informed, defensible decisions regarding tree safety and retention.
Our assessments are particularly suited for landowners, local authorities, infrastructure managers, and commercial property stakeholders who require risk management strategies grounded in evidence and best-practice methodology.
Technical Approach to Tree Risk
Tree risk is a function of three primary factors: the probability of failure, the likelihood of impact on a target, and the severity of consequences. Our assessments involve a detailed inspection and analysis of:
- Tree vitality and structural integrity
- Presence of defects such as decay, cavities, or compromised roots
- Site-specific conditions (soil volume, wind exposure, target occupancy)
- Proximity and exposure of potential targets (vehicles, structures, public areas)
Each assessment results in a structured risk rating and tailored management recommendations that are proportionate to the identified risk level.
Quantified Tree Risk Assessment (QTRA)
As a key differentiator, we are accredited practitioners of the Quantified Tree Risk Assessment (QTRA) system—a leading industry standard that translates tree risk into a quantifiable and rational framework.
Using QTRA, we assess:
- The likelihood of failure of a given tree or part thereof
- The probability of a target being present and impacted
- The potential severity of harm
This method enables risk to be expressed as a probability per annum, aligning with the tolerability thresholds used in broader risk management disciplines such as engineering and public health.
The key advantage of QTRA provides a defensible, consistent, and auditable approach to tree risk. It is particularly valuable for clients seeking to demonstrate due diligence, comply with health and safety obligations, or defend management decisions in legal or planning contexts.
Why Our Approach Stands Out
- Specialisation in tree risk audits for high-occupancy or sensitive sites
- Integration of QTRA for evidence-based, legally robust recommendations
- Clear documentation for internal policy, insurance, and planning compliance
Whether you manage a municipal tree stock, a private estate, or a commercial development, our service offers technical precision and legal defensibility—helping you manage tree risk without unnecessary removals or liability exposure.
Contact us to commission a detailed risk assessment or to integrate QTRA into your broader asset management strategy.
