2018-07-10 Planning & Environment Committee Agenda

PLANNING & ENVIRONMENT COMMITTEE MEETING AGENDA                                            10 JULY 2018




   Figure 7: Photograph taken from Main Beach looking towards the subject site and the Endiandra sieberi
                                               (Corkwood).

The applicant’s arborist report, Australian Tree Contractors & Arboricultural Consultants Pty Ltd
(TRAQ), which assesses the safety of the tree incorrectly identifies the tree is a Endiandra
Sievert sp. it is believed that this is a spelling mistake.
The report includes the following assessment:
      This Corkwood tree is growing on the side of a sandy based soil slope of approx. 32
      degrees and it has a major bias downhill….
      There is the very poor taper of the trunk to the root plate and reaction growth to the
      increased load by this phototrophic growing tree, primarily no laying down of supporting
      wood on either the tension or compression side.
      The crown has a lot of epicormic growth present which I interpret to be a direct correlation
      to the root system under severe load and stress.
      As identified in the TRAQ assessment this tree is in the process of failure although not
      necessarily immediately if left with no mitigation response to the issues identified this tree
      will fail and as the targets also identified in the TRAQ assessment are all in the target zone
      and the potential impact is very significant to both property and life.
Based on a risk assessment the report provides two mitigation options, the first option is the
complete removal of the tree and the second option is end weight crown reduction. End weight
crown reduction is the process of reducing the sail area of the crown to reduce wind stresses.
To assist with the assessment of this application an arborist was engaged by Council officers to
assess both the tree and the applicant’s report. The report considers a number of issues
associated with the tree including root plate movement, ‘lean and heave’ and ‘health and
condition’.
The result of the risk assessment performed by Council’s consulting arborist differs to the
applicants and results in a lower risk rating. The applicant’s arborist has determined a Risk Score
of ‘High’ whilst Council’s arborist score is ‘Moderate’.

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