A total of 6 trees were assessed at Yandina-Coolum Road, Coolum Beach QLD 4573 on 22 April 2025. The property is an established urban residential allotment with a mixed canopy of native and exotic species. Trees were assessed using the Visual Tree Assessment (VTA) methodology and the Quantified Tree Risk Assessment (QTRA) system.

Tree Risk QTRA has been engaged by the council Roads and Infrastructure division to undertake a Tree Risk (QTRA) and Works Priority Assessment of nine roadside trees along a rural road corridor. Target occupancy at this site is primarily vehicle traffic with continuous daily use. Statutory road clearance requirements (5.5m vertical) have been assessed for each relevant tree. The assessment was carried out on 22 April 2025 by a QTRA-certified practitioner.

The assessment was carried out on 22 April 2025 by a QTRA-certified practitioner. All trees were assessed individually using the Visual Tree Assessment (VTA) methodology, with risk quantified using the Quantified Tree Risk Assessment (QTRA) system in accordance with QTRA Ltd (2015).

Subject trees were inspected using the Visual Tree Assessment (VTA) methodology developed by Mattheck and Breloer (1998). Each tree was assessed for species, age class, health, structure, defects, proximity to targets, and arboricultural value. A Quantified Tree Risk Assessment (QTRA) was completed for each tree, producing a Risk of Harm (RoH) value expressed as a probability comparable to accepted tolerability thresholds.

The roadside corridor supports a mixed population of native species including Forest Red Gum, Swamp Mahogany, Brush Box and Angophora costata. Two trees (Trees #2 and #6) present Unacceptable risk and require urgent removal — both trees exhibit advanced structural decay with crowns overhanging the live carriageway. Two additional trees (Trees #4 and #9) present Tolerable risk and require moderate priority works within 3 months.

Target occupancy for all trees is assessed as continuous vehicular — primary target is passing vehicles, cyclists and pedestrians. This elevated and continuous target occupancy is the primary driver of risk ratings throughout this assessment and has been incorporated into each QTRA calculation.

Of the 9 trees assessed, 2 present Unacceptable risk (Trees #2 and #6) and require immediate removal — the relevant road authority should be notified and traffic management arranged. Two trees present Tolerable risk requiring moderate priority works within 3 months. Four trees require low priority clearance pruning and 2 require no works. All pruning works in the road reserve must be undertaken in accordance with traffic management requirements.

All pruning works should be undertaken by a qualified arborist in accordance with AS 4373-2007 Pruning of Amenity Trees. All retained trees should be re-inspected within a two-year timeframe.

The following table summarises the assessment findings and recommended works for all trees assessed. Works are prioritised as High (immediate action), Moderate (within 3 months), Low (within 12 months) or None (no works required at this time).

Quantified Tree Risk Assessment (QTRA) is an internationally recognised tree risk management framework that applies established risk management principles to tree safety. The assessment produces a Risk of Harm (RoH) value — a numerical probability comparable to everyday risk benchmarks.