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Attachment 4 - Treee Management Plan_V1
Plans and drawings: the text below has words only, no drawings.
ARBORICULTURAL REPORT
Tree Management Plan
Project: Site Redevelopment and Upgrades
Site Address: Ozcare Noosa
80-100 Cooyar St,
Noosa Heads, QLD, 4567
Commissioned by: Woollam Constructions
Local Authority: Noosa Council (NC)
Application No.: 132001.210127.3
Date: Tuesday, 16 July 2024
Version: 1
Prepared by:
Matthew Duncan
Director / Principal Arborist
e: [email protected]
m: 0450 355 770
ABN: 68 153 548 531
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This document was prepared for the sole use of Woollam Construction, and any regulatory agencies
involved in this project. No other party should rely on this information without the prior written consent
of Consult Arborist and the client.
The findings laid out in this report are valid for 12 months from the assessment date.
If the advice and recommendations made in this report are not strictly adhered to, no responsibility will
be taken for the continuing health and condition of retained trees. Trees are dynamic living organisms
that respond to changes in their environs; repeat assessments are key to maintaining tree vitality,
structural integrity and reducing any potential risk they may pose.
C OPYRIGHT
This report/document is subject to copyright laws and remains the property of Consult Arborist Pty Ltd.
Penalties @280c per word per incident of unauthorised usage. No part of this report may be reproduced
or used without the written permission of Consult Arborist Pty Ltd. No responsibility will be accepted by
Consult Arborist Pty Ltd for unauthorised or partial use of this report.
General Permission of use as subject to Consult Arborist Pty Ltd copyrights:
• Hard copy permission: Entire copies may be printed for use by the Client for internal or Project
liaison.
• Electronic permissions: Must be original PDF format for filing and/or limited to the agreed parties
with a direct and vested interest in the case.
D OCUMENT C ONTROL
The latest approved version of this 24_07_16_TMP_Woollam_Ozcare_V1 should be available to all
personnel involved in the Project in consultation with Consult Arborist Pty Ltd.
Each new revision should be distributed to all key personnel for review and endorsement.
All individuals working near protected trees are to be made aware of this document and it is the
responsibility of the individual to implement and/or adhere to the recommendations and guidelines.
Version Date Written Reviewed Approved
Draft 14/07/2024 MJD SCD MJD
One 16/07/2024 MJD SCD MJD
D OCUMENTS R EVIEWED
The following documents have been reviewed, analysed, and referenced during the production of this
report.
Reference / Date Title / Details
27/07/2023 Noosa Council Letter of Decision Notice – Minor Change
Tree Mark-up Tree Mark-up Plan – provided by Woollam Construction
23/03/2023 2. Fire Trail Clearance Plan – STP
240611 Site Services Overlay - with Vegetation
Note: Extracts from the above document have been used to illustrate the text within this report but should be read with full
documents.
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T ABLE OF C ONTENTS
Copyright .............................................................................................................................. 2
Document Control ................................................................................................................. 2
Documents Reviewed ........................................................................................................... 2
1 Brief ............................................................................................................................... 4
2 Site Inspection ............................................................................................................... 5
3 Scope and Limitations .................................................................................................... 5
3.1 Contractors Notes.................................................................................................. 6
3.2 Habitat Trees ......................................................................................................... 6
4 Background.................................................................................................................... 7
5 Site Plans....................................................................................................................... 8
6 Site Discussion .............................................................................................................. 9
6.1 Fire Tanks and Pump Room ................................................................................ 11
6.2 Generator and Switchboard ................................................................................. 13
6.3 Firebreak & Access Track .................................................................................... 15
6.3.1 Arborist Review................................................................................................ 17
7 Site Photos .................................................................................................................. 18
8 Tree Protection Guidelines (TPG) ................................................................................ 20
8.1 The Role of the Project Arborist and Tree Protection ........................................... 20
8.2 Calculating Tree Protection Zone......................................................................... 21
8.2.1 TPZ.................................................................................................................. 21
8.2.2 SRZ ................................................................................................................. 21
8.3 Tree Protection .................................................................................................... 22
8.3.1 TPZ Signs ........................................................................................................ 22
8.3.2 Restricted Activities Within the TPZ ................................................................. 23
8.3.3 Tree Protection Fencing (TPF)......................................................................... 23
8.4 Mitigation Measures............................................................................................. 24
9 General Excavation Methodologies .............................................................................. 25
10 Hard Surface / Asphalt Removal.............................................................................. 26
11 References: ............................................................................................................. 27
12 Assumptions and Disclaimers.................................................................................. 27
Appendix 1: Definition of Terms .......................................................................................... 28
Appendix 2: Sample TPZ Fencing Sign ............................................................................... 29
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1 B RIEF
This report has been commissioned by Woollam Constructions to fulfil the Noosa Council (NC)
DA conditions relating to the protection of the retained Allocasuarina littoralis, Black Sheoak
trees at the project site at Ozcare Noosa. Consult Arborist has been requested to provide
information on the site findings in relation to the development and offer advice and
methodologies for general tree protection of the Black Sheoak that are to be retained.
The subject trees inspected are as illustrated in the North Coast Environmental Plans, Bennett
and Bennett Site Tree Survey, STP site Civil & Track Layout plans, and Enrich Architecture
project plans.
This report is to fulfil Noosa Council conditions numbered 68 and 69 as per Decision Notice –
Minor Change letter dated 27/07/2023.
Figure 1: Extract from the Noosa Council Decision Notice – Minor Change letter dated 27/07/2023
Figure 2:Google overview of the Ozcare site and Cooyar Street, Noosa heads
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2 S ITE I NSPECTION Matthew Duncan, the Director and Principal Arborist of Consult Arborist undertook the Visual Tree and site assessments on the site from a ground level in July 2024. Matthew holds an AQF Level 5 Diploma of Arboriculture (AHC50510), an International Society of Arboriculture’s Tree Risk Assessment Qualification, valid from 2015 to 2030, and has worked in the arboricultural industry since 1994. Since its establishment in 2011, Consult Arborist has been engaged to provide arboricultural advice and guidance on private, civil, and capital works projects from cross-sector clients throughout Queensland where he is a Queensland Arboricultural Association (QAA) Qualified Member and Approved Consultant. The weather at the time of the inspection was clear with light winds, and ground conditions were dry underfoot with good access. 3 S COPE AND L IMITATIONS The arboricultural assessment for this report is based on the methods outlined in the International Society of Arboriculture’s Risk Assessment Methodology for trees. The level of assessment undertaken for this report was a basic Level 1 visual assessment of the surrounding area and the subject tree’s structure and health, from the ground on one side and a Level 2 assessment on all sides of the tree was completed to assess further any visual defects noted. No tree-specific risk assessment was undertaken for this report. It is an assessment that includes the use of basic tools and techniques, i.e., cavity probing, minor root collar excavation, measuring tapes and devices and photography to gather information and not a full assessment of any trees’ structural safety. No trunk decay detection equipment or ground radar was used as part of this Arboricultural Appraisal, no conclusive comments on what may have been or may be happening within the internal structure of the tree or the tree’s roots will be made. No tissue or soil samples have been collected or submitted for testing. All data is based on visual inspection based on known industry methodology of visual tree assessment VTA, of the tree/s and its/their location, species, health, and condition at the time of inspection unless otherwise stated. The information contained in this report is based on a visual inspection of each recorded tree and its location, species, health, and condition at the time of inspection unless otherwise stated. It is the author's opinion and is a 'snapshot in time' of the specific tree's health and condition at the time of the inspection and no guarantee can be given that faults or issues may not arise in the future. The relevant tree information has been recorded to be used as a functional tool to determine management strategy for the subject trees, considering attributes, conditions, past works, location, project design, construction, and future use. Site plans have been provided and used for reference with no changes to the design. See the attached site photographs and site maps/plans for identification purposes. 24_07_16_TMP_Woollam_Ozcare_V1 Page 5 of 29
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Recommended arboricultural works are to be carried out by an arborist holding a minimum of a Level 3 AQF qualification in Arboriculture with good working experience. It is expected that the Arborist may encounter anomalies within the tree as they climb/work and as such may use their discretion to remove any further branches or limbs which they may deem could pose an immediate risk. Additional removals outside the recommendations or defects noted whilst in the tree are to be recorded and reported to the author and/or discussed with a Level 5 Arborist on site prior to undertaking the appropriate action. All pruning is to be guided by AS 4373 – “Pruning of Amenity Trees”, industry best practice and experience. The use of an Elevated work platform (Cherry picker) is recommended to allow for safe access to the outer branches and more accurate pruning. When undertaking remedial tree works on habitat trees, please be aware of the fauna and their habitat. The creation of future habitat whilst undertaking remedial works is to be considered. When mitigating hazardous deadwood, hollow sections and large branches, minimal pruning or reduction of weight is required rather than total removal. Hollow sections take many years to be created and are a highly valuable habitat. Coronet cuts should be facilitated where appropriate to mimic natural branch failure on suitable trees in a natural setting. Please note all site activities are to be agreed upon and implemented in accordance with all Health & Safety, Environmental and Cultural Heritage best practices with the approval provided by the appropriate project entities. 24_07_16_TMP_Woollam_Ozcare_V1 Page 6 of 29
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4 B ACKGROUND
Consult Arborist has been engaged to provide arboricultural advice relating to the project
design and plans at the Noosa Ozcare site at 80-100 Cooyar Street, Noosa Heads. This report
focuses on the retention status of Black Sheoak trees found throughout the site within the
project scope.
The site is an existing residential care facility that is surrounded on the north, east and
southern side by the Girraween Nature Refuge. The redevelopment of site includes the
demolition and redevelopment of existing buildings, relocation and upgrades to services and
associated infrastructure, and the creation of a fire break and access track.
As per of the approval conditions, an Arborist Report is required to provide advice on the
retention and protection of retained trees. This advice will be guided by AS4970-2009
Protection of trees on development, industry best practice and experience.
The tree survey and tree plot as part of a Verification Plot was undertaken by Bennett and
Bennett, and extracts will be used and embellished to inform this report.
Figure 3 :Bennett and Bennett tree plot front cover plan
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5 S ITE P LANS
Figure 4: Services plan provided by Woollam illustrating the locations for the Fire Water Tanks next to the
Cooyar Street entrance and the new and ungraded Switch Board, and Generator.
The internal site services alignment is to be confirmed
Figure 5: STP Earthworks/track Layout plan to provide a project overview, with the Pink shaded area
illustrating the Firebreak and Access Track.
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6 S ITE D ISCUSSION The Ozcare property is located within a mix of natural and planted trees and vegetation. With the site built approximately 30 years ago, most of the landscape planted trees have reached their mature size and, in many areas, naturally occurring trees have grown up and infilled spaces. The existing site facility is proposed to be upgraded with the redevelopment of existing buildings. This includes the upgrade of inground services with a new Fire Tank and Pump Room and new Generator and Switchboard to be installed on the western side of the site that abuts the natural road verge of Cooyar Street. In recent years the creation of a Fire Break around the north and eastern site of the property was approved. These works are planned to be undertaken as part of the upgrade and in the process an access track will be created that will facilitate the construction phase of the project. The Black Sheoak, Allocasuarina littoralis, has been highlighted as a tree species requiring special consideration due to its importance to the local fauna, particularly the Glossy Black Cockatoo. The Black Sheoak is a fast-growing semi-pioneer species which is found throughout the site and the surrounding areas of Noosa and the Sunshine Coast. A broad age class of these trees are found within the project scope area of the site. Clumps of emerging, naturally occurring trees are along the edge of the Girraween Bushland, individual semi-mature trees are throughout the site and mature and advanced-age trees are found in areas that have not been disturbed in recent decades. Black Sheoaks as a species, have a relatively short life expectancy as a mature tree and they are highly susceptible to localised change which can bring about sudden decline, death, and failure. On observing the older trees on site, there is common trend for them to succumb to environmental or site changes, quickly succumbing to root plate failure when infected with a decay fungus. Commonly this fungus was noted as a Ganoderma species with fruiting bodies found on both failed and on the standing trunks of older trees. The fungus attacks the tree’s main trunk heartwood timber and structural roots, frequently resulting in root plate failure. This can be seen throughout the site on many occasions. 24_07_16_TMP_Woollam_Ozcare_V1 Page 9 of 29
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Figure 6: T43 - Recently failed Black Sheoak with Figure 7: T9 - Mature Ganoderma fruiting body on
Ganoderma fruiting body on the lower trunk Black Sheoak trunk
Where possible the Black Sheoak are proposed to be retained at the site except where
required to be removed to accommodate the approved project plans. An assessment of these
trees was made based on each tree’s current Health, Condition, project constructability, and
workplace Health and Safety. The results of this assessment are provided in the following
sections.
The site findings and arborist review are laid out to cover the three main areas of tree related
conflict and protection or mitigation measures required.
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The location for the proposed Fire tanks, Pump Room and associated infrastructure is on the
northern side of the Cooyar Street driveway site access.
On attending site, the project design was clearly pegged providing a visual representation of
the proposed design. This essential infrastructure requires the removal of approximately 20
trees of differing species and age class, predominantly Paperbarks and Wattles.
One small Black Sheoak, with a strong lean that appears to be being held up by an adjacent
tree, will be directly conflicted by the design and requires removal.
The closest mature Black Sheoaks are found within the adjacent verge next to the concrete
path, close to the existing Booster. Currently, it is predicted that these trees will be retained
during the project, but when the adjacent trees are removed these two would be left exposed
in an area of considerable change. This change is likely to lead to a decline in the tree’s health
rendering them unsuitable for retention.
In the interest of site accessibility and safety both during and immediately after the completion
of the works, they are recommended for removal as part of these works.
Figure 8: Fire Tanks and Pump Figure 9: Bennett and Bennett Tree plot extract
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Figure 10: Google Street View 2022 - overview of the site from the road and the location of the existing
booster (red square) and two Black Sheoaks (marked in light green), and the ‘SITE’ of the Pump Room
While the Water Tank and Pump Room dictates the removal of the trees that are in direct
conflict with the footprint, it is recommended that an additional 1-2m of trees are cleared for
work site access and project constructability. The Project Arborist is to finalise the clearing
limits with Woollam Construction and the location of the Exclusion Zone demarcation.
Inground and pipes and/or services will be exiting the Pump Room towards the main site. The
alignment is shown to be within the existing road which will reduce further tree removals.
Where tree conflict occurs, additional trees will be removed. This is likely to include a few
Paperbarks and an advanced-age Wattle with a major mid-stem union defect. It is proposed
that any tree in direct conflict with the alignment will be removed in consultation with the Project
Arborist. Reduced impact techniques can be used to lessen the conflict on the tree roots with
the aim of retaining suitable trees. This can include localised tunnelling beneath roots and
Hydro Excavation. An Exclusion Zone to protect retained trees will be established and
managed as per Tree Protection Procedures.
Figure 11: Wattle trees behind existing Booster to be Figure 12: Yellow line approximate trench location.
removed Old Wattle with major union defect.
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The Generator and Switchboard are proposed to be relocated closer to the existing Electrical
Transformer on the western side of the carpark.
On attending site, the project design was clearly pegged providing a visual representation of
the proposed design. The construction of essential infrastructure will require the removal of
approximately 10 trees of differing species and age class. The prominent species are Broad-
leaved Paperbarks and multi-stemmed Wattles, with no Black Sheoaks within the proposed
footprint of the Generator works site.
The closest mature Black Sheoaks are found next to the existing concrete path that runs
between the proposed Generator site and the existing Electrical Transformer. It is likely this
path may require repositioning, and this may impact the adjacent trees. The closest mature
Black Sheoaks are found within the adjacent verge next to the concrete path, close to the
existing Transformer. Currently, it is predicted that these trees will be retained during the
project, but when the adjacent trees are removed these two would be left exposed in an area
of considerable change. This change is likely to lead to a decline in the tree’s health rendering
them unsuitable for retention.
In the interest of site accessibility and safety both during and immediately after the completion
of the works, they are recommended for removal as part of these works. The two Sheoaks are
numbered T20 and T21 in the Bennett and Bennett Tree Plot.
Figure 13: Generator and Switchboard design Figure 14: Bennett and Bennett Tree plot extract
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Figure 15: Tree 20 & 21 recommended for removal.
Yellow box – Generator site location
Figure 16: Overview of the Generator site - yellow box. Existing Transformer - red box. Mature Black Sheoak
T20 & T21 - light green. Trees to be removed - red crosses.
It is proposed that all connecting trenching alignments will enter and exit from the carpark side
of the work site.
While the Generator site dictates the removal of the trees in direct conflict with the footprint, it
is recommended that an additional 1-2m of trees are cleared for work site access and project
constructability, this includes trees 20 and 21. The Project Arborist is to finalise the clearing
limits with Woollam Construction and the location of the Exclusion Zone demarcation.
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On the northern to eastern aspect of the site is an existing break in the vegetation that
separates the Girraween Nature Refuge bushland and the site. As part of previous approvals,
Noosa Council gave consent to clear all but the Black Sheoak trees to create a firebreak.
These works were not completed and are now proposed as part of these project works.
A review of the Black Sheoak trees was undertaken as part of this Arborist Assessment. A
separate tree plot plan was provided by Woollam illustrating the Black Sheoaks within the
Firebreak. Table 1 below highlights the observations noted during the site inspection and the
current retention status for these trees. Please note that the number sequencing is not always
continuous, and trees not reflected in the following table are deemed suitable to be retained
at this time.
The status of the remaining young trees at the southern end of the site is questionable. It is
difficult to determine which tree is which on site and their long-term suitability for retention is
questionable with natural fails anticipated in coming years.
Figure 17: Tree markup plan provided by Woollam illustrating the numbered Black Sheoaks
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Figure 18: Tree markup plan provided by Woollam illustrating the numbered Black Sheoaks
Figure 19: Tree markup table provided by Woollam
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6.3.1 Arborist Review
Tree ID Condition Comments Retention Status
1 Failed and resting in adjacent Wattle trees Remove
2 Not identified on site *
3 Not identified on site *
Strong phototropic growth habit over the property boundary
8 Remove
and over the roof of the existing building.
Past side stem failure.
9 Mature Ganoderma bracket fungi on the main trunk. Remove
Unsuitable for retention.
Retain.
Untypical growth habit in the canopy.
Prune to improve form
Will require corrective pruning.
10 and structure.
Tree likely to succumb to localised changes resulting in
Monitor monthly during
canopy decline.
the project.
11 Inside the property boundary next to the boundary peg. NA / Remove
Retain.
12 Tri stem with strong asymmetrical growth towards the track. Prune to improve form
and structure.
The tree appears to be recently deceased with foliage turning
Reinspect in 1 month.
13 brown.
Removal predicted.
Low branches over the access track.
Design review to
Semi-mature tree on the edge of a clump, likely conflict with
22 confirm removal
the Access Track works.
requirements.
Large mature tree in average condition.
Monitor monthly during
25 Concerns regarding the tree’s condition once the surrounding
the project.
trees and vegetation are removed.
Strong asymmetrical growth habit towards the access track.
Prune for access.
Will require 50% canopy removal for access, this will likely
27 & 32 Monitor monthly during
have detrimental effects on the tree’s health and long-term
the project.
retention status.
40 & 41 Not identified on site *
43 Recently failed Remove
Design review to
70 - 72,
Young Trees with questionable retention confirm removal
79
requirements.
76-78 Not identified on site *
Table 1: Arborist observations within firebreak
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7 S ITE P HOTOS Figure 20: Tree 1 Figure 21: Tree 8 Figure 22: Tree 9 Figure 23: Tree 10 Figure 24: Tree 11 Figure 25: Tree 12 Figure 26: Tree 13 Figure 27: Tree 22 Figure 28: Tree 25 24_07_16_TMP_Woollam_Ozcare_V1 Page 18 of 29
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Figure 29: Tree 27 Figure 30: Tree 32 Figure 31: Tree 43
Figure 32: Location of trees 40, 41 & 43
Figure 33 Location of young trees possibly 70-72
Figure 34: Location of trees 76 - 78
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8 T REE P ROTECTION G UIDELINES (TPG) For the proposed retention of the above trees onsite, the following guidelines are recommended to be implemented to minimise the impact of the Project works. The protection recommendations offered will be guided by, AS4790 – 2009 Protection of trees on development sites, industry best practice and the supervising presence of a suitably qualified and experienced Arborist with a high level of experience as an onsite Project Arborist. The information within these Guidelines is generic and can be used within the project as required. The successful retention of the trees will be bettered by the education and cooperation of all parties of the construction team during the build and the presence of the Project Arborist on site to assist and advise during the construction phase for all works carried out adjacent to the TPZ of protected trees. ALL workers on the site are to be made aware of the Tree Protection Guidelines and any site- specific measures by the main contractor prior to commencing works. An Arboricultural Assessment was undertaken by the Project Arborist for the trees that require consideration. The information within this Tree Management Plan (TMP) should be read in conjunction with guidelines laid out in the Australian Standard, AS4970–2009 Protection of Trees on Development Sites and ongoing advice from the Project Arborist. A designated onsite foreman/supervisor from the construction company is to liaise with the Project Arborist to ensure that Tree Protection is adhered to in their absence from the site. A Post Construction Arborist Report can be prepared by the Project Arborist on request for the retained tree comprising a Visual Tree Assessment detailing each of the trees’ condition and vigour, damage or disturbance which may have occurred, and remedial works are undertaken. After the final inspection, a Certification of Compliance can be supplied along with any monitoring documentation as required. The Project Arborist may at any time implement new or additional procedures as may be required for the site in the best interest of the trees and the development as a whole. 24_07_16_TMP_Woollam_Ozcare_V1 Page 20 of 29
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The descriptions of the TPZ and SRZ are taken from the Australian Standards, AS 4970-2009
Protection of trees on development sites. These descriptions only give the basic outline to
calculate the TPZ and SRZ, when encroachment or reduction in the size/area of the TPZ is
required to facilitate the development, these can also be calculated: see Appendix D of the
Australian Standard AS 4970-2009.
8.2.1 TPZ
As specified in the Australian Standard, AS 4970-2009, the Tree Protection Zone (TPZ) is the
principal means of protecting trees on a development site. The TPZ is a calculation that
combines the root area and crown area which require protection and this area should be
isolated from construction disturbance so that the tree can remain in a viable condition for the
future. The TPZ incorporates the Structural Root Zone (SRZ).
The radius of the TPZ is calculated for each tree by multiplying its DBH (Diameter at Breast
Height - trunk diameter measured at 1.4m above ground) by 12.
E.g., a tree with a .5m diameter at 1.4m x 12 results in a 6m Tree Protection Zone (TPZ).
A TPZ should not be less than 2m or greater than 15m (unless crown protection is required).
8.2.2 SRZ
The Structural Root Zone, as specified in AS 4970-2009 the surface area of protection that is
required around a tree to maintain that tree’s stability – a larger area than this is required to
maintain a tree in a viable condition for the future. It is only necessary to calculate the SRZ
when major encroachment into a TPZ is proposed.
An indicative SRZ radius can be determined from the trunk diameter, D, measured in metres
(above the root buttress) and applying the following formula:
0.42
RSRZ = (D x 50) x 0.64
The SRZ for trees with a trunk diameter less than 0.15m will automatically be 1.5m.
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Figure 35 below shows a typical representation of a tree protection system. Tree’s root
systems are generally shallow with most of the roots found within the top 1m of soil with a
higher density of roots found closest to the surface where moisture and nutrients are more
readily available. The function of the TPZ (Tree Protection Zone) is to ensure that the tree has
a viable root system, so the tree has a functional future as an amenity asset within the
development.
The structural standing of a tree is linked to critical aspects of roots (found in the TPZ) to bind
the soil and create a mass that the tree can anchor to. These roots consist of ‘Secondary roots’
(medium size) and ‘Tertiary roots’ (small size).
Primary roots (large size) found in the SRZ connect the Tree to the anchor system. Primary
roots by themselves do not bind enough soil to create a stable anchor system.
The shallow nature of tree roots should be taken into consideration when working close to
trees and when installing the tree protection fencing for the Tree Protection Zone (TPZ).
Figure 35: Example of an ideal generic Tree Protection System
8.3.1 TPZ Signs
The signs, sample to be found at Appendix 2 – Sample TPZ Sign, identifying the TPZ are to
be placed around the edge of the TPZ in locations visible to the site as per Tree Protection
Fencing Standards Australia marketing media AS4970 – 2009.
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8.3.2 Restricted Activities Within the TPZ Restricted activities within the TPZ / Exclusion Zone that would cause harm to the retained trees to include, but are not limited to: • Any non-approved construction works. • Any non-approved excavation or cultivation of the ground. • Any non-approved storage. • Preparation of chemicals, including cement products. • Parking of vehicles and plant. • Refuelling. • Dumping of waste. • Wash down and cleaning of equipment. • Placement of Fill. • Lighting fires. • Any non-approved soil level changes. • Temporary or permanent installation of utilities and signs. • Physical damage to the tree. 8.3.3 Tree Protection Fencing (TPF) The Tree Protection Fencing (TPF) is to be steel mesh panels (as detailed in AS4687-2007 Temporary fencing and hoardings) and held in place with concrete feet, the nut and bolt holding the clamps are to be secured and tightened with a spanner to prevent the fence from being easily moved and to restrict access to those with permission only. Shade cloth or something similar can be attached to the fence to protect the area from airborne matter if required. Uneven ground and/or exposed sites may require additional staking to hold the fencing in place. Care is to be taken when installing the additional bracing not to damage tree roots or hit underground services. Where the adequate TPZ is not achievable the TPF can be erected in a non-standard alignment and additional measures including ground protection, e.g., Trak-mats/geo fabric and mulch to spread the load of site activities and minimise ground disturbance. These measures will be established between the developer and the Project Arborist. As an alternative to steel mesh panels for temporary or low access areas, TPZ fencing may consist of 1m high plastic orange mesh barrier fencing or a double row of flagging with star pickets with end caps as support, spaced at 4 – 5m and attached with zip ties. This style of fencing is deemed suitable for larger sites when work activities are generally to be within the central area of the site with the proposed retained trees on the periphery and away from main site activities. 24_07_16_TMP_Woollam_Ozcare_V1 Page 23 of 29
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Remediation measures can be undertaken to limit and reduce any negative effects that may
occur. Where suitable the retained trees’ TPZ areas are to be improved to provide a more
favourable and beneficial growing environment for the tree’s roots.
Where the soil levels are required to be raised a sandy loam is to be used. This will improve
drainage and allow for gaseous exchange. Trees can adapt to low levels of Fill being placed
over the existing ground if undertaken with the correct material. In some cases, this additional
medium can also provide ideal rooting conditions for feeder roots and a beneficial food source
for the tree.
The following recommendations could be taken to improve an existing plant’s vigour, and will
in turn benefit the plant’s health, safety, and the amenity that it provides and can be
incorporated with the project landscaping details.
Where groundworks are carried out adjacent to or encroaching into the TPZ areas the
following mitigation measures and procedures should be implemented where deemed
appropriate and should be supervised by Consult Arborist.
• Where possible the excavated ground, including the cut roots, will be covered/backfilled
with quality topsoil locally sourced or a sandy loam/river sand with low organic matter, as
guided by AS 4419—2003. Australian Standard™ Soils for landscaping and garden use.
• An application of seaweed-based soil conditioner/plant food can be applied to the topsoil
as per the manufacturer’s guidelines. Monthly applications are recommended for the
duration of the project.
• When required supplemental watering with a water cart or sprinkler system can be used
to retain adequate moisture levels in the soil.
• The Project Arborist is to advise and oversee all mitigation measure works being
undertaken on retained trees.
All tree works, and tree protection measures, are to be guided by industry best practices and
the relative Australian Standards which include but are not limited to:
• Australian Standards AS4970-2009 Protection of trees on development sites
• Australian Standards AS4373-2007 Pruning of amenity trees
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9 G ENERAL E XCAVATION M ETHODOLOGIES
Details below give examples of works methodology to excavate a trench or general excavation
when working in proximity to trees.
When using a mechanical excavator ground protection is advisable to minimise compaction
and damage to the surrounding soil and roots. With a combination of a small bucket and ripper,
the spoil from the trench can be carefully extracted. General excavation is to be undertaken,
when possible, with the bucket positioned perpendicular to the tree, and the spoil dug away
from the tree, this helps to minimise roots being accidentally torn or fractured.
When excavations are being undertaken within a tree's root zone, all necessary precautions
are to be adhered to. The Project Arborist will advise on the progression of the works and
undertake root pruning as required.
Roots deemed to be pruned and removed are to be carefully cut using a sharp saw and/or
secateurs. Root removal is carried out by the Project Arborist on a root-by-root basis taking
into consideration the type of tree, distance from the cut to the tree, and the size and number
of roots found.
Where possible trenches and excavations are to be carefully backfilled using topsoil from the
site or imported topsoil with a low organic matter content and lightly compacted by hand within
the tree zone. Ideally, the ground is then irrigated to increase moisture in the soil (not
waterlogged) and where possible 100mm of mulch is spread to cover the surface area.
Where possible create a preliminary trench/excavation at the outer edges of the required cut
line using a Hydro-vacuum excavator. Roots found can be cleanly cut by the Project Arborist.
Once the preliminary cut line is completed excavation of the remaining area outside the cut
line can be dug using the appropriate excavator with all due care and attention to the adjacent
protected trees.
Figure 36: Example of preliminary trench/excavation cuts
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10 H ARD S URFACE / A SPHALT R EMOVAL The Project will require the removal of the existing path/hard surface adjacent to the retained subject trees. They will require careful removal overseen by the onsite Project Arborist working alongside the contractors. Sections of the old surface can be removed with the use of an excavator whilst positioned and working away from the tree. Machinery is not to be used on unprotected or bare ground within the TPZ or Exclusion Zone. The excavation of any ground within or adjacent to retained trees should be cut perpendicularly to the tree to reduce the likelihood of roots being split or damaged longitudinally and is to be overseen by the Project Arborist. If roots are uncovered and determined to be cut, sharp handsaw or secateurs are to be used to ensure a clean cut at a right angle to minimise the cut surface area. On completion of the demolition works any exposed roots are to be covered with either damp hessian or sandy loam to protect the roots from drying out before the construction of the new surface. 24_07_16_TMP_Woollam_Ozcare_V1 Page 26 of 29
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11 R EFERENCES :
• the Australian Standards AS4970-2009 Protection of trees on development sites (2009).
• Australian Standards AS 4373 – 2007 Pruning of amenity trees. (2007).
• Barton, A. (2003). Wild plants of greater Brisbane. South Brisbane, Qld, Australia: Published by the Queensland Museum,
in partnership with the Environment and Parks Branch of the Brisbane City Council.
• Dunster, J., Smiley, E., Matheny, N. and Lilly, S. (n.d.). Tree risk assessment manual.
• Haslam, S. and Hauser, J. (2011). Noosa's native plants. Tewantin (Qld.): Noosa Integrated Catchment Assoc. Inc.
• Hayes, E. (2001). Evaluating tree defects. [S.l.]: Safetrees.
• Lonsdale, D. (1999). Principles of tree hazard assessment and management. London: Forso as estry Commission.
• Mattheck, C., Breloer, H., Lonsdale, D. and Strouts, R. (2003). The body language of trees. London: The Stationery Office.
• Strouts, R. and Winter, T. (1998). Diagnosis of ill-health in trees. Colegate, Norwich: Crown.
• IACA, 2010, IACA Significance of a Tree, Assessment Rating System (STARS), Institute of Australian Consulting
Arboriculturists, Australia, www.iaca.org.au
12 A SSUMPTIONS AND D ISCLAIMERS
This information contained in this report has been prepared on an independent basis, free of any bias and represents the honest
opinion of the consulting arborist.
All data is based on a visual inspection of the tree/s and its/their location at the time of writing, unless otherwise stated, and
contains opinions, advice and recommendations based on information and data gathered from site inspections carried out by the
author and information supplied by the Client (Woollam Construction Pty Ltd).
All information received from the Client shall be deemed to be true, accurate and up to date.
To the extent permitted by law, you agree Consult Arborist Pty Ltd is not liable to you or any person or entity for any loss of or
damage caused or alleged to have been caused (including loss or damage resulting from negligence) either directly or indirectly,
by your use of the information made available in this report. In no event will the author be liable to you for any lost revenue or
profits, or for special, indirect, consequential, or incidental damage (however caused and regardless of the theory of liability)
arising out of or related to your use of that information, even if the author has been advised of the possibility of such a loss or
damage.
Consult Arborist cannot be held responsible for the effects of non-conformance works performed, by unsuitably qualified staff or
without the supervision of Consult Arborist.
Unless otherwise stated this report cannot be used within a court of law or any legal situation without the prior consent of Consult
Arborist Pty Ltd. The author shall not be required to give testimony or to attend court by reason of this report unless subsequent
contractual arrangements have been made.
The information contained in this report refers only to the tree/s that were inspected in July 2024 and reflects the condition of the
tree/s at the time of the inspection.
There is no warranty or guarantee, expressed or implied, that the problems or deficiencies of the plants or property in question
may not arise in the future. Likewise, remedial treatments cannot be guaranteed.
Arboriculturalists cannot detect every condition that could possibly lead to the structural failure of a tree. Trees are living
organisms that fail in ways we do not fully understand. Conditions are often hidden within trees and below ground. Consult
Arborist Pty Ltd and the author cannot guarantee that a tree will be healthy or safe under all circumstances, or for a specified
period of time.
This report does not take into consideration the possibility of extreme weather or other events over which Consult Arborist Pty
Ltd has no control.
Treatment, pruning and removal of trees may involve considerations beyond the scope of the Arboriculturalists services, such as
property boundaries and ownership, disputes between neighbours, sightlines, landlord-tenant matters and related. Consult
Arborist Pty Ltd cannot take such issues into account unless the complete and accurate information is given to them. Likewise,
Consult Arborist Pty Ltd cannot accept any responsibility for the authorization or non-authorization of any recommended treatment
or remedial measure.
Arboriculturalists are tree specialists who use their education, knowledge, training, and experience to examine trees, recommend
measures to enhance the beauty and health of trees and attempt to reduce the risk of living near trees. Trees can be managed,
but they cannot be controlled. To live or work near a tree involves some degree of risk. The only way to eliminate all risks
associated with a tree is to eliminate the tree.
Clients may choose to accept or disregard the recommendations of Consult Arborist Pty Ltd or to seek additional advice.
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A PPENDIX 1: D EFINITION OF T ERMS
Age Class (AC):
Y Young: Early stage of growth, immature size
EM Early Mature: Fast-growing well-established tree which has not yet, reached mature size
M Mature: The tree reached its mature size, and exhibits slowing growth rates with early stages of naturally forming
dead or dysfunctional wood.
OM Over Mature: The tree has reached mature size and is unlike to increase significantly in height or mass.
Retrenchment of the upper crown with increased vegetative vitality in the lower crown, increased fungal activity
and wood decay, and increased colonisation by flora and fauna.
V: Veteran: Tree with advanced retrenchment, reduced crown size and annual increment growth, extensive hollowing,
crown collapse, low vigour, advanced heartwood decay, advanced colonisation by fauna and flora.
Health (H):
GH Good: Tree with no defects or disorders which are notable. Full canopy with good colour foliage. Minimal pathogen
damage.
FH Fair: Tree with minor defects or disorders which are notable. Some dead wood within what can be an unbalanced
canopy, foliage generally with good colour although some discolouration may be present typical of species in
location. Minor pathogen damage.
PH Poor: Tree with major defects or disorders which are notable. The tree has considerable deadwood present, and
discoloured or distorted leaves indicating a further decline of the tree. Detrimental pathogen damage.
D Dead or dysfunctional moribund tree.
Structure (St):
GS Good: Tree with good unions and no branch defects. Sound trunk with no / minor defects. Good buttress and root
structure.
FS Fair: Tree with minor defects or disorders which are notable. Small areas of bark missing. Small cavities or minor
unfavourable branch unions may be present. Minor damage to roots.
PS Poor: Tree with major defects, large hollows, weak unions and/or problematic damaged roots.
HS Hazardous: This implies a tree with a major defect that may fail at any time.
Abbreviations:
Ht Height
CS Crown Spread
DBH Diameter at Breast Height - The approximate diameter of the trunk measured visually in millimetres or meters at a
height of 1.4m.
TPZ The Tree Protection Zone, as per AS 4970-2009 Protection of trees on development sites, is the principal means
of protecting trees on a development site. The TPZ is a combination of the root and crown area requiring protection
to be isolated from construction disturbance so that the tree can remain in a viable condition. The TPZ incorporates
the Structural Root Zone (SRZ).
The radius of the TPZ = DBH x 12
A TPZ should not be less than 2m or greater than 15m (unless crown protection is required).
SRZ The Structural Root Zone, as per AS 4970-2009 Protection of trees on development sites, is a mathematical
calculation of the surface area of protection required to maintain a tree’s stability – a larger area is required to
maintain a tree in viable health. It is only necessary to calculate the SRZ when a major encroachment into a TPZ
is proposed.
Recommended Works:
Aerial Inspection: Assessment is to be carried out either by Consult Arborist or a Qualified Arborist contractor to assess
defects within the canopy and report findings.
Canopy A combination of removing dead wood and selective pruning to benefit the tree’s future health and
management: canopy structure. The end-weight reduction of longer lateral branches, with the creation of future
growth points to sustain canopy growth and assist with natural canopy retrenchment.
Deadwood and detail Remove deadwood (>40mm in diameter and/or 1m in length), and dysfunctional, damaged, and weak
branches from the tree’s canopy.
End-weight Trimming of the concentration of excessive wood and foliage weight towards the extremity of the
reduction: branch to lessen the overall load and branch failure potential.
Mulch: The application of a layer of woodchip/forest mulch approximately 50-75 mm thick to the canopy drip
line where possible, leaving a small well around the base of the tree trunk.
Palm clean Remove dead / dying fronds and seed pods or nuts.
Proactive removal To prevent future anticipated issues, remove the tree and replant with a more suitable species for the
location.
Prune away from Prune branches to reduce the encroachment and weight of the branches growing towards the adjacent
adjacent dwelling. dwelling/building.
Reduce and retain Reduce the tree to a safe height and size to limit hazards while retaining the remainder for habitat.
Reinspect A repeat assessment is recommended to be carried out 12 months from the date of this assessment
or after any major weather event.
Selective pruning Prune selective / identified branches to reduce end weight/length.
Soil/Plant Care Apply organic compost around the base of each tree 20-30mm thick, leaving a small well around the
base of the tree trunk. Additional seaweed-based plant food/soil conditioners applied as per the
manufacturers’ guidelines and will help to improve soil biology and maintain the tree’s health.
Stump grind Remove the stump by grinding to approximately 100mm below the surrounding ground level when
located within mown grass or damaging infrastructure.
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( onsult \rborist APPENDIX 2: SAMPLE TPZ FENCING SIGN onsult rborist Today's trees for tomorrow Tree Protection Zone N@ ACCESS Tree Protection Measures are in place as per AS 4970-2009: No unauthorised entry of persons or plant for any reason. No works of storage in or near this zone. This tree protection barrier should remain in good condition and must not be altered or removed. « Refer to the Arborist Reports for more details. Australian Standards, AS 4970-2009, Protection of trees on development sites For more information contact: Phone: 24_07_16_TMP_Woollam_Ozcare_V1 Page 29 of 29