Approved Document OPW18-0319 · OPW18/0319

                                                                                  Consult Arborist

5 V ISU AL T REE R ISK A SSESSM ENT R ESULTS
The assessment commenced at the northern end of the Buffer Zone and preceded south along
the western edge. The subject trees were previously marked with flagging tape to aid
identification. To provide continuity, the trees were assessed in the same order as the previous
assessment, where possible with tree additional trees.

Tree attributes are approximately measured visually unless otherwise stated.

5.1   TREE 1 – SWAMP MAHOGANY
 ID         Genus & Species                         Common Name
 1          Eucalyptus robusta                      Swamp Mahogany
 Height                    Crown Spread             [email protected]          Age
 18-20m                    8-10m                    600-700mm                Over-mature
 Health                                             Structure
 Fair to Poor with depleted canopy                  Fair to Poor with typical die-back in the main
                                                    branch structure
 Target                             Occupancy                        Target Zone
 Residential dwelling               Constant                         Within 1 x height & Dripline
 Comments
 The tree is located within a bushland setting with no evidence of ground disturbance on the tree's
 tension side. A main feature of the tree is a dominant lean to the main trunk, likely developed when
 young and seeking light (phototrophic). No evidence of root plate failure/heave over the recent years
 that would have contributed to the lean was confirmed.

 The canopy displays typical decline for this species when in an advanced stage of life. Natural
 retrenchment and regrowth creating twig/branch die-back and deadwood with responsive epicormic
 growth creating new growth are evident throughout the main branch structure.

 Tree 1 is directly targeting a Unit with the upper canopy encroaching over the roof.

 This is a known Koala food tree and generally a good habitat tree.

 The risk matrix has been calculated on branch failure as this has been deemed the most likely event
 to occur within the next 12 months.
 Likelihood of Failure            Likelihood of Impacting Target       Matrix 1 - Result
 Probable                         High                                 Likely
 Consequence of Failure           Matrix 2 – Overall Risk Rating       Work Priority
 Significant                      High                                 Within 30 days
 Recommendations
 Canopy management is recommended to reduce the canopy away from the adjacent dwelling.
 Pruning will likely exceed the recommended 20% removal of lost live foliage but will retain a more
 stable tree and an acceptable height that will reduce the likelihood of further branch failure in the
 near future and create a tree that can be managed into the future.

 This species are known for being responsive to pruning with the creation of prolific regrowth formed
 by epicormic shoots. These works will also reduce canopy sail area and, although unlikely, the
 likelihood of total failure.

 Re-inspect in 12 months.
 Residual Risk on completion of Mitigation Options
 Low




19_01_24_TRA_RACV Resort _Noosa_V3                                                        Page 8 of 32