GUIDELINES FOR TREE RISK ASSESSMENT AND MANAGEMENT ARRANGEMENT

GUIDELINES FOR TREE RISK ASSESSMENT AND MANAGEMENT ARRANGEMENT GREENING, LANDSCAPE AND TREE MANAGEMENT SECTION DEVELOPMENT BUREAU NOVEMBER 2015 (8 th Edition) 1

GUIDELINES ON TREE RISK ASSESSMENT AND MANAGEMENT ARRANGEMENT CONTENTS Page No PART 1 RESPONSIBILITIES OF TREE MANAGEMENT DEPARTMENTS 1.1 Purpose 1 1.2 Objectives 1 1.3 Structure of Guidelines 2 1.4 Integrated Approach in Tree Management 2 1.5 Strategic Risk Assessment in Tree Management 3 1.5.1 Identify Your High Priority Areas for Tree Risk Assessment 3 1.5.2 Prioritise Resources for Valuable Trees and High Risk Trees 3 1.5.3 Mitigate Tree Risk to Protect Public Safety 3 i

Page No PART 2 TREE RISK ASSESSMENT 2.1 Identify Your Land Allocation and Tree Stock 4 2.2 Undertake Tree Risk Assessment on Area Basis 4 2.2.1 Categorisation of Tree Risk Management Zones 5 2.3 Undertake Tree Risk Assessment on Tree Basis 6 2.4 Tree Basis Assessment Tree Group Inspection (Form 1) 7 2.4.1 The TRIAGE System 9 (a) TRIAGE Trees 9 (b) TRIAGE Classification and Colours 9 2.4.2 Trees for Mitigation Measures or Individual Tree Risk Assessment (Form 2) 12 2.5 Tree Basis Assessment Individual Tree Risk Assessment (Form 2) 13 2.6 Sensitivity Analysis 15 2.6.1 Trees for Sensitivity Analysis 15 2.6.2 Checklist for Sensitivity Analysis 16 2.7 Mitigation Measures 17 2.8 Record Keeping 18 2.9 Audit Inspection 19 ii

Page No PART 3 LANDSCAPE AND LOCATION CONDITONS 3.1 Objectives 20 Figure 3.1.1 - Location Types of Stonewall Trees (SWT) with Surface Attachment on Stonewall 21 Figure 3.1.2 - Stonewall Trees (Modes of Failure) 22 Figure 3.2 - Location Types of Trees in Confined Space 23 Figure 3.3 - Location Types of Trees with Ground Disturbance 24 Figure 3.4 - Location Types of Trees on Slopes 25 iii

Page No PART 4 TREE CARE 4.1 Management 26 4.2 Maintenance 29 4.3 Monitoring 31 4.4 Compliance 33 iv

Page No PART 5 FORMS TEMPLATES CHECKLISTS 5.1 Forms 34 5.2 Templates 35 5.2.1 Reporting 35 5.2.2 Signs and Notices 36 5.3 Checklists 37 5.3.1 Checklist: Equipment / Tools and Personal Protective Equipment for Tree Inspection 38 5.3.2 Checklist: Photographic Documentation for Tree Risk Assessment 40 5.3.3 Checklist: Emergency Response 42 5.3.4 Checklist: Sensitivity Analysis 43 5.3.5 Checklist: Tree Removal (non-emergency situation) 44 v

Page No APPENDICES Appendix 1 Appendix 2 Appendix 3 - Working Examples of Demarcation of Tree Risk Management Zone - Overall Workflow of Tree Risk Assessment and Management Arrangement - Requirements for Inspection Officers and Endorsement Officers (Form 1) A1-1 A2-1 A3-1 Appendix 4 - Form 1: Tree Group Inspection Form A4-1 Appendix 5 - Explanatory Notes for Form 1 A5-1 Appendix 6 - Photo-taking Guidelines for Tree Risk Assessment A6-1 Appendix 7 - Requirements for Inspection Officers and Endorsement Officers (Form 2) A7-1 Appendix 8 - Form 2: Tree Risk Assessment Form A8-1 Appendix 9 - Explanatory Notes for Form 2 A9-1 vi

PART 1 RESPONSIBILITIES OF TREE MANAGEMENT DEPARTMENTS 1.1 PURPOSE The Guidelines for Tree Risk Assessment and Management (TRAM) Arrangement serve to provide technical and performance guidance on tree risk assessment, management, monitoring and maintenance. The key objectives are to: (a) Maximise public safety (b) Establish sustainable tree care practices The Guidelines for TRAM Arrangement are based on international best practices with due consideration to the circumstances in Hong Kong. They should only be applied, supervised and endorsed by qualified inspection and endorsement officers when exercising their professional judgment. They should not be used in a prescriptive manner, nor inhibit the development of new techniques or approaches that aim to add value to existing tree management practices. During the process of tree risk assessment, tree management departments, inspection officers and endorsement officers should consider the life-cycle of the tree and its relationship with its surrounds. 1.2 OBJECTIVES For Tree Management Departments Recognise your role and responsibilities in TRAM for all trees within your purview. Understand the importance of prioritising resources for undertaking TRAM of trees within high priority areas. Understand the importance of quality tree maintenance and risk assessment in protecting public safety. For TRAM Inspection and Endorsement Officers Recognise your role and responsibilities in delivering quality TRAM work. Follow the Guidelines for TRAM Arrangement. Demonstrate competency and professionalism in your tree risk assessment. Greening, Landscape and Tree Management Section 1

1.3 STRUCTURE OF GUIDELINES The Guidelines comprise the following five parts, together with a list of supplementary appendices. Part 1 highlights the purpose and objective of the Guidelines, and the importance of adopting an integrated approach and strategic risk assessment in tree management. Part 2 provides the overall framework and details in implementation of tree risk assessment. Part 3 provides examples of a series of location types of trees highlighting unfavourable tree growth conditions affecting tree stability. Part 4 covers a set of baseline considerations to help the decision making process in tree care. Part 5 provides some practical checklists to facilitate tree management works. 1.4 INTEGRATED APPROACH IN TREE MANAGEMENT The Government has adopted an integrated approach in assigning responsibilities for preserving and maintaining trees on Government land among relevant departments. It is the responsibility of all tree management departments to manage all assets, including trees, within areas, facilities and premises under their maintenance ambit. A holistic process is adopted to the management of our assets. It is fundamental to understand that our trees are inextricably connected to and thus impacted by numerous bio-physical, bio-mechanical and urban conditions. Hence, the more dense and compact our urban environment, the more stress our trees will suffer. Trees grow on land that is managed by a range of responsible parties. This land may also contain soil, other vegetation and a host of other infrastructure and landscape elements that must be managed and maintained in a holistic manner. Greening, Landscape and Tree Management Section 2

1.5 STRATEGIC RISK ASSESSMENT IN TREE MANAGEMENT Making reference to overseas best practices and taking into account the urban conditions in Hong Kong, the TRAM is based on a dual approach Area Basis Assessment and Tree Basis Assessment. Area Basis Assessment Identify high priority areas where public will be affected if a tree fails. Tree Basis Assessment Identify valuable trees (i.e. Old and Valuable Trees and stonewall trees) and high risk trees within high priority areas. Assess tree conditions in accordance with a standardised format with emphasis on the risk angle. 1.5.1 Identify Your High Priority Areas for Tree Risk Assessment Tree management departments are required to identify areas where tree failure will pose a hazard to public safety, damage to property or cause disturbance to human activity and hence categorise the land under their management into tree risk management zones according to the intensity of use in target areas. 1.5.2 Prioritise Resources for Valuable Trees and High Risk Trees By identifying valuable trees and high risk trees, tree management departments can allocate resources to conduct tree risk assessment efficiently and undertake appropriate mitigation measures as far as practicable in a timely manner to alleviate tree risk and prioritise management of these trees. 1.5.3 Mitigate Tree Risk to Protect Public Safety Human safety is the most important aspect in tree risk management. Tree management departments must undertake management diligence to keep trees in healthy and structurally sound conditions, identify hazardous trees and take appropriate mitigation measures as far as practicable in a timely manner to protect human safety. In case of conflict between tree preservation and public safety, the latter should be given the higher priority. Greening, Landscape and Tree Management Section 3

PART 2 TREE RISK ASSESSMENT 2.1 IDENTIFY YOUR LAND ALLOCATION AND TREE STOCK Before carrying out tree risk assessment, tree management departments have to: # Requirements 1 Reconfirm the extent of all areas with trees under your maintenance ambit. It is recommended to refer to the Geospatial Information Hub (GIH) in the Government intranet (http://gih.landsd.ccgo.hksarg/gih-hksar/view/hgh.jsp) and check with Lands Department on the extent of all your land allocation. 2 Ensure all trees under your maintenance ambit are included in your tree risk assessment and maintenance works. 2.2 UNDERTAKE TREE RISK ASSESSMENT ON AREA BASIS Tree management departments are required to categorise all the sites under their management into tree risk management zones with reference to the intensity of use in target areas. The tree risk assessment on an Area Basis aims to: (a) Identify areas where tree failure will pose a hazard to public safety or cause disruption to human activity; and (b) Prioritise resources for tree risk management according to the frequency of use of the area. Targets are people, property, or human activity that can be injured, damaged, or disrupted by a tree failure, e.g. partial or complete road closure. A tree cannot be a hazard without the presence of a target. For sites managed by departments, tree risk management zones are determined based on the intensity of use in target areas which would be affected by tree failure. Greening, Landscape and Tree Management Section 4

Such site categorisation also covers sites temporarily under the management of works departments during the course of public works projects. Works departments have to approach the departments that previously managed the trees, including the Maintenance Agent of SIMAR Slopes if any, to obtain the records of previous tree inspections for at least one year or as appropriate, and familiarise themselves with existing tree conditions prior to commencement of works. 2.2.1 Categorisation of Tree Risk Management Zones Categorisation of tree risk management zones is shown in the following table. Intensity of Use in Tree Risk Priority for Tree Risk Target Area Management Tree Risk Assessment Zone Management Frequency Intensive use High Top priority At least once a Areas of high traffic flow and (Category I) year before high pedestrian flow including onset of wet public parks, playgrounds, season (i.e. 30 crowded streets, busy April) and when carriageways, car parks, busy necessary (e.g. footpaths, areas adjacent to act on schools, buildings, etc. complaint) Infrequent use Medium Second Every 3 to 5 Areas of low traffic flow and (Category II) priority years, low pedestrian flow such as if resources road verges of limited access, permit, and countryside roads, village when necessary footpaths, etc. (e.g. act on complaint) Rare use Low Low priority When necessary Areas of rare access such as (Category III) (e.g. act on inaccessible areas, remote complaint) countryside slopes, dense woodlands, maintenance access not open for public, etc. Greening, Landscape and Tree Management Section 5

Appendix 1 - Working Examples of Demarcation of Tree Risk Management Zone 2.3 UNDERTAKE TREE RISK ASSESSMENT ON TREE BASIS Once high tree risk management priority areas (i.e. Category I Zones) are identified, tree management departments are required to undertake the risk assessment on tree basis for trees within Category I Zones. # Actions 1 Identify the valuable trees and high risk trees within Category I Zones. 2 Assess health and structural conditions of the identified trees systematically and professionally with particular emphasis on the risk perspective. 3 Use standardised forms promulgated by the GLTMS to record the inspection findings. Appendix 2 - Overall Workflow of Tree Risk Assessment and Management Arrangement Greening, Landscape and Tree Management Section 6

2.4 TREE BASIS ASSESSMENT TREE GROUP INSPECTION (FORM 1) # Objectives of Tree Group Inspection (Form 1) 1 Facilitate initial screening of trees within Category I Zones. 2 Keep records for further monitoring. 3 Identify potential tree hazards for appropriate mitigation measures or for more detailed individual tree risk assessment using Form 2. # Actions for Undertaking Tree Group Inspection (Form 1) 1 Follow requirements for Inspection Officers and Endorsement Officers in Appendix 3 to undertake Tree Group Inspection. 2 Inspect each tree in the tree group systematically. 3 Follow requirements as stipulated in Section 2.4.1 to undertake TRIAGE System. 4 Pay particular attention to potential tree hazards due to the health or structural conditions of each individual tree. 5 Use binoculars to obtain a closer view of the conditions of the canopy if necessary. 6 Use appropriate equipment and hand tools such as mallet, hand spade and probe, etc. for preliminary assessment of individual trees when required. 7 Conduct sounding tests when required, for trunks or accessible scaffold limbs with decay or suspected decay cavity, to assess the extent of structural problems. 8 Undertake mitigation measures for trees with minor defects to mitigate tree risk. 9 Decide if an Individual Tree Risk Assessment will be necessary for a particular tree. 10 Record all the findings in Form 1: Tree Group Inspection Form in Appendix 4. 11 Provide photo records in accordance with requirements as listed in Appendix 6. Greening, Landscape and Tree Management Section 7

For users with Tree Management Information System (TMIS) accounts, the use of Form 1 under the TMIS format is recommended. Appendix 3 - Requirements for Inspection Officers and Endorsement Officers (Form 1) Appendix 4 - Form 1: Tree Group Inspection Form Appendix 5 - Explanatory Notes for Form 1 Appendix 6 - Photo-taking Guidelines for Tree Risk Assessment Greening, Landscape and Tree Management Section 8

2.4.1 The TRIAGE System The Triage system is only for trees in Category I Zones. The purpose is to: (i) Identify trees that require more urgent attention than others. (ii) Prioritise these trees based on a combination of factors that impact a tree s structural health. (iii) Prioritise mitigation works based on the TRIAGE classification of a tree. (a) TRIAGE Trees Dead trees Trees confirmed with Brown Root Rot (BRR) disease infection Old and Valuable Trees (OVTs) Stonewall trees Mature trees with an individual trunk(s) over 750mm DBH (b) TRIAGE Classification and Colours How TRIAGE System works? Tree management departments have to classify their trees as per Section 2.4.1(a) within Category I Zones into the following three categories; Black = Hazardous: Trees programmed to be removed Red = Problematic: Trees identified for prompt inspection and mitigation measures Yellow = Remaining Triage Trees: Trees not in Black and Red category Greening, Landscape and Tree Management Section 9

Categorisation, necessary action and monitoring requirements of Black, Red and Yellow trees are illustrated in the following tables. Black Criteria Dead trees Non-OVTs confirmed with BRR disease infection Action 1. Tree removal within 4 weeks after completion of Form 1 inspection; or 2. If removal cannot be completed in 4 weeks, departments have to provide appropriate temporary mitigation measures as far as practicable to ensure public safety. Monitoring Requirement 1. For Non-OVTs confirmed with BRR disease infection, (a) Undertake Form 2 assessment every 3 months to monitor the tree condition until the removal of the tree; and (b) Upload the tree information to the Tree Register. RED Criteria OVTs confirmed with BRR disease infection Mature trees with individual trunk(s) over 750mm DBH / OVTs / stonewall trees with crown spread within dripline of confirmed BRR disease infected tree Mature trees with individual trunk(s) over 750mm DBH / OVTs / stonewall trees having one or more of the following major structural defects or health problems: (i) Open cavity on trunk having the longest axis 1/3 trunk diameter; (ii) Co-dominant trunk with included bark / decay / cavity / split in the union; (iii) Decay / damage with more than 120 degree in the root flare; (iv) Over 20% die-back of crown; (v) Presence of wood decay fungi at trunk and / or root zone within dripline. Action 1. Undertake Form 2 assessment and complete appropriate mitigation measures within 6 weeks as far as practicable after completion of Form 1 inspection. Greening, Landscape and Tree Management Section 10

RED Monitoring Requirement 1. Close monitoring by Form 2 assessment: (a) Every 3 months for BRR infected OVTs. (b) Every 6 months for remaining Red category trees; and 2. Upload the tree information to the Tree Register; and 3. Undertake emergency inspection within 7 calendar days as far as practicable after the lowering of: (a) Typhoon Signal No. 8 or above; and (b) Red or Black Rainstorm Signal. The emergency inspection should focus on the damage, stability and potential hazard that the tree poses to the public. Downgrading Mechanism 1. To downgrade a Red category tree to Yellow category, tree management department needs to: (a) Undertake all the mitigation measures as recommended in Form 2 assessment to alleviate the potential tree risk. (b) Record the completion date of mitigation measures in Form 2. (c) Provide reports and photos on the mitigation measures. (d) Confirm the major structural defects or health problems have been mitigated. (e) Record the recommendation for downgrading the tree to Yellow category in Form 2. (f) Update the tree information in the Tree Register. YELLOW Criteria Mature trees with individual trunk(s) over 750mm DBH / OVTs / stonewall trees that are not classified in Black and Red category. Action 1. Undertake Form 2 assessment and provide appropriate mitigation measures for OVTs and stonewall trees. 2. Undertake appropriate mitigation measures for mature trees with individual trunk(s) over 750mm DBH having structural defects or health problems; and undertake Form 2 assessment if necessary. 3. Undertake Form 2 assessment and provide appropriate mitigation measures for mature trees with individual trunk(s) over 750mm DBH that have no visible structural defects or health problems if resources permit. The Form 2 assessment and associated mitigation measures can be completed by 31 October every year. Monitoring Requirement 1. Undertake Form 2 assessment every 6 months for OVTs and stonewall trees; and 2. Upload the tree information of OVTs and stonewall trees to the Tree Register. Greening, Landscape and Tree Management Section 11

2.4.2. Trees for Mitigation Measures or Individual Tree Risk Assessment (Form 2) For other trees in Category I Zones not assessed through TRIAGE System, tree management departments are required to identify the trees with the following criteria in Tree Group Inspection for implementing proper mitigation measures and undertaking Individual Tree Risk Assessment (Form 2) if necessary. Trees on a complaint list with structural or health problems. Trees belonging to species with brittle wood structure and having unsatisfactory health or structural conditions with failure potential. Trees with major defects or health problems. Trees growing in very stressful site conditions with failure potential. If a detailed tree risk assessment of individual tree is required, Form 2 shall be used for assessment on the tree conditions and formulation of appropriate mitigation measures. Greening, Landscape and Tree Management Section 12

2.5 TREE BASIS ASSESSMENT INDIVIDUAL TREE RISK ASSESSMENT (FORM 2) Form 2 is used for conducting detailed assessment of individual trees that need more attention. For all the OVTs and stonewall trees, tree risk assessment with Form 2 is required every 6 months to enhance close monitoring the conditions of these trees. # Actions for Undertaking Individual Tree Risk Assessment (Form 2) 1 Follow requirements for Inspection Officers and Endorsement Officers in Appendix 7 to undertake Individual Tree Risk Assessment. 2 Walk completely around the tree to inspect the site conditions, root collar, trunk, and branches including inspection of the tree from some distance away, as well as close up, to assess the tree condition in relation to its surroundings. 3 Use appropriate equipment and hand tools such as binoculars, mallet, hand spade and probe, etc. when required. 4 Conduct sounding tests for trunks or accessible scaffold limbs with decay or suspected decay cavity to assess the extent of structural problems. 5 Conduct root collar inspection for trees growing at confined sites or having suspected root defects which may adversely affect tree stability. 6 Conduct aerial inspection (if necessary) to assess the structural conditions for trees in areas with frequent use and suspected structural defects which are difficult to inspect at ground level. 7 Make reference to the Guidelines on Brown Root Rot Disease (http://www.trees.gov.hk/filemanager/content/attachments/guidelines_on_bro wn_root_rot_disease(version_for_the_general_public)en.pdf)and Note on Common Wood Decay Fungi on Urban Trees of Hong Kong (http://www.trees.gov.hk/filemanager/content/attachments/note_on_common _Wood_Decay_Fungi_on_Urban_Trees_of_HK(May2015).pdf) for tree inspection. 8 Make reference to Part 3 Landscape and Location Conditions for inspection of stonewall trees, trees in confined space, trees with ground disturbance and trees on slopes. 9 Rate the tree hazard with recommendations on follow-up mitigation actions to address the identified defects and tree problems. 10 Follow the Management Guidelines for Mature Trees (http://www.trees.gov.hk/filemanager/content/attachments/paper_mature_tre es_(finalised_and_issued).pdf) and Management Guidelines for Stonewall Trees (http://www.trees.gov.hk/filemanager/content/attachments/guilelines_for_ston e_wall_trees.pdf) in conducting tree inspection and formulating mitigation measures. 11 Record all the findings in Form 2: Tree Risk Assessment Form in Appendix 8. 12 Provide photo records in accordance with requirements as listed in Appendix 6. Greening, Landscape and Tree Management Section 13

For users with TMIS accounts, the use of Form 2 under the TMIS format is recommended. Appendix 7 - Requirements for Inspection Officers and Endorsement Officers (Form 2) Appendix 8 - Form 2: Tree Risk Assessment Form Appendix 9 - Explanatory Notes for Form 2 Appendix 6 - Photo-taking Guidelines for Tree Risk Assessment Greening, Landscape and Tree Management Section 14

2.6 SENSITIVITY ANALYSIS OVTs, stonewall trees and trees of particular interest often draw intense public attention. When removal of these particular types of trees is necessary, tree management departments are required to undertake a Sensitivity Analysis to consider the potential social impact to the community for advance planning and decision-making before tree removal. The purpose of Sensitivity Analysis is to address social concern, to improve communication and prepare proactive responses to stakeholders in the community. The objective of Sensitivity Analysis is to enhance transparency, assist in communication with the Expert Panel on Tree Management (EPTM) members, and address potential public concern on particular tree removal. 2.6.1 Trees for Sensitivity Analysis Tree management departments are to undertake Sensitivity Analysis when considering the proposed removal of the following types of trees under non-emergency circumstances: OVTs; Stonewall trees; and Trees of particular interest, such as rare species or trees of cultural significance. Examples of trees of particular interest are listed as below for reference: Rare tree species listed in Rare and Precious Plants of Hong Kong (http://herbarium.gov.hk/publicationspreface.aspx?booknameid=1) published by Agriculture, Fisheries and Conservation Department. Endangered plant species protected under the Protection of Endangered Species of Animals and Plants Ordinance (Cap 586). Well-known Fung Shui trees. Landmark trees with evidential records to support the historical significance of the trees. Trees which may arouse widespread public concerns. Trees which may be subject to strong local objections on removal. Greening, Landscape and Tree Management Section 15

2.6.2 Checklist for Sensitivity Analysis Responsible officer of senior professional rank or equivalent is recommended to follow the checklists to undertake the Sensitivity Analysis. # Checklist: Actions 1 Report to the departmental directorate level of the tree management department on the proposed removal of tree. 2 Explore alternative options of mitigation measures. 3 Directorate level officer to validate tree removal proposal and options of mitigation measures; and evaluate reporting requirements to address public concern on the tree removal proposal. # Checklist: Communication 1 Consult GLTMS on the proposed mitigation measures. 2 Involve other relevant professionals for further site inspection or review alternative mitigation measures if necessary. 3 If tree removal is still considered necessary, engage concerned stakeholders in communication prior to commencement of any tree works. 4 Prepare proactive responses to stakeholders in the community. # Checklist: Documentation 1 Tree Risk Assessment Forms (i.e. Form 1 and 2). 2 Tree Risk Assessment reports, e.g. tree inspection reports by resistography or sonic tomography. 3 Records of mitigation measures. 4 Previous maintenance records. 5 Compliance with reporting requirements and standards. Greening, Landscape and Tree Management Section 16

2.7 MITIGATION MEASURES To ensure public safety, tree management departments are required to carry out necessary mitigation measures, such as tree pruning, installation of support system, pest and disease control, site condition improvement works and / or tree removal promptly to alleviate the risk of failure. # Requirements 1 Refer to the Guidelines on Arboriculture Occupational Safety and Health (http://www.trees.gov.hk/filemanager/content/attachments/osh_guideline s_2012_dec_issue.pdf) issued by the GLTMS and ensure adequate occupational safety and health measures in carrying out the tree works. 2 Refer to the guidelines promulgated by the GLTMS on proper pruning practices, such as General Guidelines on Tree Pruning (http://www.trees.gov.hk/filemanager/content/attachments/guideline.pdf) and Do s and Don ts in Pruning (http://www.trees.gov.hk/filemanager/content/attachments/factsheet.pdf). 3 Refer to the Guideline on Pavement Renovation Works and Tree Stability (http://www.trees.gov.hk/filemanager/content/attachments/guidelines_on_ Tree_Preservation_during_Development.pdf) issued by the GLTMS for trees in stressful site conditions. 4 Refer to the guidelines promulgated by the GLTMS on pest and disease control, such as Guidelines on Brown Root Rot Disease (http://www.trees.gov.hk/filemanager/content/attachments/guidelines_on_ Brown_Root_Rot_Disease(version_for_the_general_public)EN.pdf) and Note on Common Wood Decay Fungi on Urban Trees of Hong Kong (http://www.trees.gov.hk/filemanager/content/attachments/note_on_comm on_wood_decay_fungi_on_urban_trees_of_hk(may2015).pdf). 5 Refer to the Proper Planting Practice Staking and Guying (http://www.greening.gov.hk/en/preservation/new/staking_guying_eng_au g2011.jpg) promulgated by the GLTMS on installation of supporting system. Tree management departments are required to follow the requirements as stated in the Technical Circular on Tree Preservation (DEVB TC(W) No. 7/2015) to carry out tree removal and compensatory planting as far as practicable. Factors, such as available growing space and soil to sustain healthy tree growth, gradient of slopes, etc. have to be considered. Greening, Landscape and Tree Management Section 17

2.8 RECORD KEEPING Departments are required to keep retrievable and accurate records of tree risk assessments, risk mitigation measures and monitoring programme undertaken for the trees under their management. For OVTs, stonewall trees and trees that require regular monitoring, tree management departments need to upload the tree information to the Tree Register to enhance transparency and facilitate community surveillance of the condition of the trees concerned. # Actions 1 Upload relevant information on the following trees that have been identified in the tree risk assessment to the Tree Register at www.trees.gov.hk (a) Black TRIAGE tree confirmed with BRR disease infection that cannot be removed within 4 weeks after completion of Form 1 inspection. (b) Red TRIAGE trees. (c) Yellow TRIAGE OVTs and Stonewall trees. (d) Trees that require regular monitoring. 2 Refer to Guidelines on Tree Register data input and updating in the Cyber Manual for Greening for uploading the required tree information in a timely manner onto the Tree Register for public information. 3 Departments have to closely monitor the conditions of those trees included in the Tree Register so that timely actions can be taken in response to any change in the tree conditions. Greening, Landscape and Tree Management Section 18

2.9 AUDIT INSPECTION Tree management departments are required to set up a departmental audit checking mechanism to: (a) Ensure tree risk assessment is carried out properly and professionally. (b) Ensure necessary mitigation measures are carried out promptly. # Actions 1 Refer to Guideline for Auditing of Tree Risk Assessment for Tree Management Departments in Cyber Manual for Greening. 2 The audit checks shall cover tree risk assessments carried out by in-house staff and / or tree risk assessments conducted by outsourced service providers. 3 Conduct the audit checks as soon as practicable to monitor the quality of the assessment. 4 Review the accuracy and completeness of records. 5 Check for appropriateness of the mitigation measures and against the timelines for completion. 6 Follow up promptly with any irregularities identified during the audit checks. 7 Tree risk assessments and related procedures carried out by departments are subject to further audit checks by the GLTMS. Greening, Landscape and Tree Management Section 19

PART 3 LANDSCAPE AND LOCATION CONDITONS 3.1 OBJECTIVES Healthy trees with sound structure are valuable assets to the community. Very often, trees are confronted with various environmental stresses such as space limitation, soil compaction, lack of nutrients, abnormal soil ph, damage by construction and roadwork activities, etc. where restricted root growth, root damage and soil disturbance leading to poor root anchorage are major factors causing tree decline thus affecting stability. A series of location types of trees highlighting unfavourable tree growth conditions affecting tree stability, such as trees on stonewalls, in confined space, with ground disturbance and on slopes are identified to draw special attention when undertaking the tree risk assessment in order to minimise the potential tree risk. Greening, Landscape and Tree Management Section 20

Figure 3.1.1 - Location Types of Stonewall Trees (SWT) with Surface Attachment on Stonewall Root spread on masonry wall (a) Surface attachment (b) Surface attachment and (c) Surface attachment and (d) Surface attachment and only ground roots at toe ground roots at crest ground roots at crest and toe Structural condition Support solely by the surface Support by the surface root mass on Support by the surface root mass on Support by the surface root mass on of tree anchorage root mass on wall with unknown wall with unknown amount of root wall with unknown amount of root wall with unknown amount of root amount of root penetration penetration and additional ground penetration and additional ground penetration and additional ground roots Roots are mostly confined within roots protruded to the wall toe roots protruded to the wall crest protruded to both wall crest and toe masonry wall only Only limited physical support could Provides additional strength on the Provides additional strength on the be provided by roots at toe tension side of SWT for anchorage tension side of SWT for anchorage Health Condition Nutrient / water uptake limited to Nutrient / water uptake would be Nutrient / water uptake would be Nutrient / water uptake would be confined space behind the facilitated by the extended ground facilitated by the extended ground facilitated by the extended ground roots masonry wall roots at wall toe roots at wall crest at both wall crest and toe Attention on tree High High Low Low anchorage (among stonewall trees) Greening, Landscape and Tree Management Section 21

Figure 3.1.2 - Stonewall Trees (Modes of Failure) A. Tree trunk failure B. Root detachment failure C. Shallow-root anchorage failure D. Overall failure Greening, Landscape and Tree Management Section 22

Figure 3.2 - Location Types of Trees in Confined Space Trees grown in confined space (a) Tree Pit (b) Small (Raised) Planter (c) Planter Box Structural condition on Open bottom planter Open bottom planter Closed bottom planter tree anchorage Typical tree pit size is around 1.2 m (L) x 1.2 m Sinker root could be developed for tree Roots confined within planter box (W) x 1.0 m (D) anchorage Tree anchorage depends on the size of planter Extent of root spread outside the tree pit is Extent of root spread depends on the planter box and relative size of the tree uncertain as most of the surrounding soil is size and relative size of the tree generally compacted or ground surface paved Health condition Nutrient / water uptake would highly depend on Nutrient / water uptake would highly depend on Nutrient / water uptake would highly depend on maintenance maintenance maintenance Attention on tree Medium to Low (depending on extent of paving Medium to Low (depending on the planter size) High anchorage around tree pit) Greening, Landscape and Tree Management Section 23

Figure 3.3 - Location Types of Trees with Ground Disturbance Trees with ground disturbance (a) Trenching (b) Cutting (lowering of level) (c) Filling (raising of level) Structural condition on tree Poor root anchorage due to imbalanced Poor root anchorage due to imbalanced root Existing root system would become stressed and anchorage root system caused by removal of roots system caused by removal of roots within the suffocated, and the tree may eventually die within the dripline dripline No soil filling should be allowed within dripline to the No further trenching / cutting of roots No further cutting of roots should be allowed trunk and above root flares should be allowed Large roots cut from lowering of level may Large roots cut from trenching may easily easily be infected by decay organisms and be infected by decay organisms and extended to lower trunk over time extended to lower trunk over time Health condition Nutrient / water uptake would be affected Nutrient / water uptake would be affected by Tree health may decline over time due to lack of by the physical root loss the physical root loss oxygen, inadequate soil aeration and poor drainage Crown dieback on the trenching side Crown dieback in the cutting side would be Health decline may not immediately become obvious would be obvious in the first year after obvious in the first year after cutting trenching Attention on tree anchorage High High Low Greening, Landscape and Tree Management Section 24

Figure 3.4 - Location Types of Trees on Slopes Trees on Slopes (natural or man-made slopes) Trees grown on slopes Leaning tree with no sign of self-correction Trees on Hard Surfaced Slopes (shotcreted and/or with granite stone facing) Slope surface may not be uniform (a) Trees in tree rings (b) Trees in berm planters (c) Trees in toe wall planters Tree Risk Assessment Considerations (tree leaning and root anchorage) Modes of failure Extent of root development on tension side Defects in roots on tension side Root anchorage (loosen / cracked / uneven soil within root zone) Extent of leaning versus height of tree Sign of increased extent of leaning when compared with previous inspection Condition of reaction wood on tension side Root failure (e.g. root decay, poor attachment) Site history (condition of site under hard paved surface) Extent of roots that are visible on the slope Conditions of roots that are visible Position of tree on slope Extent of leaning / falling zone Anomalies of slope surface around tree Root failure (e.g. root decay, poor attachment, girdling roots) Exposed roots spill over planter edge Aggressive root growth causing damage to planter wall Refer to items (b) in Figure 3.2 Trees in Confined Space Root failure (poor root anchorage, exposed roots, girdling roots) Exposed roots spill over planter edge Aggressive root growth causing damage to planter wall Refer to items (b) or (c) in Figure 3.2 Trees in Confined Space Root failure (root decay, poor root anchorage, exposed roots, girdling roots) Attention on tree anchorage High High Medium High Greening, Landscape and Tree Management Section 25

PART 4 TREE CARE Responsible tree care is a team effort. Its success is founded upon the clarity of roles, responsibilities and communication amongst internal and external personnel. The following sections provide a set of baseline considerations to help the decision making process in delivering quality work to international best practice. 4.1 MANAGEMENT The table below illustrates the different levels of responsibilities in the process of decision-making: Strategic Decision (directorate) Establish the direction of steer. Formulate principles of judging the alternatives. Brainstorm and analyse the different choices. Give steer. Oversee outcome. Evaluate feedback and prioritise departmental resources. Professional Decision (managerial) Recognise the need for a steer. Generate alternatives. Evaluate the alternatives. Green light to execute or seek steer. Monitor outcome. Gather feedback. Evaluate feedback and refine work processes. Operational Decision (frontline) Identify, verify and establish the tree problem. Carry out assessment and determine the constraints. Identify alternatives and recommend the preferred option. Execute or seek steer. Evaluate results and provide feedback. Greening, Landscape and Tree Management Section 26

Purpose To maximise the long-term efficiency and effectiveness of tree management, maintenance, monitoring and compliance. # Actions 1 A robust institutional set up of qualified and trained in-house staff to undertake the required duties to meet the short, medium and long-term delivery on all aspects of tree management. 2 A strategic framework to progressively procure, train and qualify in-house staff to meet the short, medium and long-term needs. 3 Verify tree works are carried out, supervised, monitored and validated by relevant personnel. 4 Communication and consultation are efficiently and effectively undertaken to manage public expectations and sensitivities. 5 The tree management supply chain complies with all requirements at all stages of works. # Communication 1 Communication framework that clearly identifies the following: Chain of command; Feedback loops; Timeframes for communicating to different parties; Consultation requirements to parties such as, but not limited to: stakeholders; local residents; District Councils; government departments, bureaux and agencies; Method of communication and consultation such as types and frequency of meetings; notifications; forums; displays. 2 A developed and tested emergency communication procedure in the event of tree failure or emergency tree removal. 3 Suite of communication templates that can be readily deployed to succinctly and factually articulate: Upcoming scheduled works; Chronology of events; Progressive updates. 4 Assigned personnel to execute the communication framework across all stages of works. Greening, Landscape and Tree Management Section 27

# Documentation 1 A robust set of contract documents and technical specifications that covers all required aspects of tree care to meet the quality standards as detailed in all relevant Technical Circulars, Guidelines and Standards, the British Standards BS3998, the American National Standards ANSI Z133 and ANSI A300 as the reference. 2 Contract documents that clearly articulate the following: Defined standards-based scope of works. Required services with onus on the Contractor to deliver methodology of works; completeness of documentation; inspection points; sign-offs; regulatory approvals during all stages of works. Measurable outputs through contract enforcement procedures. 3 Verify documentation and compliance to record-keeping standards and protocols. Greening, Landscape and Tree Management Section 28

4.2 MAINTENANCE Quality tree care starts when a tree is selected and planted. Good maintenance assures the tree s sound establishment and healthy growth throughout its life, minimises remedial costs and significantly contributes to tree safety. Purpose To instil a positive culture and quality practices toward the long-term care of your tree assets and minimise risk to As Low As Reasonably Practicable (ALARP). # Actions 1 Confirm that the contract specifies all maintenance requirement details. 2 Conform to government planting guidelines and international best practices. 3 Right tree in the right place: Plant with clear objectives. Choose the right species. Procurement of quality nursery stock: Buy young, buy healthy. Thorough site and stock preparation before planting. Provide and maintain optimal environment for healthy tree growth such as but not limited to: adequate aerial and underground space for sustainable growth; fertile soil of appropriate type, well aerated, correct soil volume and optimum moisture content; proper drainage. 4 Structural training at right age and right time to achieve structural integrity for life. 5 Draw up maintenance planner to plan ahead and coordinate effectively. 6 Engage qualified professionals to assess and maintain the trees. Undertake TRAM to maximise tree safety (Part 2 refers). 7 Instil proper arboricultural practice in all facets of tree maintenance. 8 Protect trees from construction damage. 9 Build and upkeep staff knowledge, skills and quality of work through continuous training and knowledge sharing. # Communication 1 Proactive communication both internally and externally with suppliers and contractors for: Recognising areas for improvement for prompt follow-up; Establish feedback loop for improvement; Regular review of maintenance planner to improve workflow and better use of resources. 2 Close and constant liaison with suppliers for provision of quality stock and equipment. 3 Maintain supervisory accountability through establishing communication two-way across all levels to facilitate supervision and reflection. Greening, Landscape and Tree Management Section 29

# Documentation 1 Succinct and informative maintenance manual. 2 Clear, retrievable maintenance records. 3 Up to date inventory or database of tree asset. 4 Regular Scheduled Programmed update of tree inventory with a particular focus on OVTs, stonewall trees, TRIAGE Red trees and trees require regular monitoring (Section 2.8 refers): Update information on Tree Register. Update input to TMIS. Greening, Landscape and Tree Management Section 30

4.3 MONITORING Improvement in tree management performance relies on continuous monitoring and evaluation which help track work progress and facilitate decision making. Monitoring and evaluation processes can be undertaken in-house or outsourced, but independence of the monitoring team is important in ensuring credibility. Purpose To validate the integrity of your tree management programme and facilitate continuous feedback and improvement. # Actions 1 Establish clear objectives in drawing up the monitoring programme. 2 Sound, systematic and consistent monitoring methodology. 3 Compliance check against contract specifications, government guidelines and regulations. 4 Desktop review for quality of output and deliverables. 5 Site checks for accuracy against written records. 6 Track progress. 7 Promptly rectify identified anomalies. Investigate and analyse the cause. 8 Carry out regulatory actions as required. 9 Forward-looking evaluation to improve workflow and refine approaches. 10 Review effectiveness and make adjustments in future work. # Communication 1 Clear chain of command for effective communication and prompt follow-up. 2 Evidence based findings clearly conveyed to staff and contractors. 3 Clear time frame for reporting rectified output. 4 Inform management on systematic issues identified. Greening, Landscape and Tree Management Section 31

# Documentation 1 A set of record that clearly articulate the following: Date, time, personnel involved, type of tree management work, observations, result of each monitoring event; All communications with outsourced service provider (consultants and contractors); Follow-up action of identified anomaly and / or disorder. 2 Monitoring manual with clear objectives, methodology and schedule. 3 Retrievable records of monitoring results. 4 Updated records of rectified deliverables. 5 Report on systematic issues and improvement recommendations. Greening, Landscape and Tree Management Section 32

4.4 COMPLIANCE Compliance reflects competence and success of departments in meeting the required standards and delivery of quality work. It involves an ongoing process of auditing and monitoring. Purpose To validate the accuracy of tree management actions, communication and documentation against current internal and external policies, procedures, regulations and guidelines. # Actions 1 Establish systematic internal control procedures that comply with the Guideline for Auditing of Tree Risk Assessment for Tree Management Departments (Section 2.9 refers). 2 Engage independent personnel to achieve an objective audit. 3 Identify key elements for audit. 4 Review output and deliverables for evidence of non-compliance. 5 Investigate the cause of non-compliance. 6 Explore ways to rectify non-compliance. 7 Recommend improvement measures to prevent recurrence of non-compliance or non-conformity. 8 Review the need for refinement of departmental policies, strategies, regulations, guidelines, procedures and resource allocation. 9 Identify and recommend areas for long term improvement. # Communication 1 Verify compliance to set communication processes. 2 Verify completeness of communication and consultation material including but not limited to: minutes of meetings; follow-up actions; confirmation of recorded information; prompt correction to inaccurate or misleading public statements. 3 Auditors to maintain constructive communication with auditees. 4 Auditees to receive feedback from auditors with openness. 5 Encourage information sharing on feedback and recommendation to bridge performance gaps across different teams of the department. # Documentation 1 Audit manual or guideline with clear objectives, scope and schedule. 2 Retrievable records of audit results and recommendations. 3 Retrievable records of improvement measures implemented. Greening, Landscape and Tree Management Section 33

PART 5 FORMS TEMPLATES CHECKLISTS Good planning and close supervision are essential to the delivery of quality tree management work. This part provides some tools including forms, templates and checklists to assist you in carrying out your work more effectively. You can customise them to suit your departmental use. 5.1 FORMS Good forms help to define the scope and level of details of the data required, standardise the format of the acquired data to facilitate data management and analysis, and provide structured way of understanding the attributes of the tree management results so that the senior management can understand how results are reported. The Form 1 and 2 provided under this guideline serve to list out the fundamental details that the Inspection Officer has to collect on site and any supplementary information including photos, site plans, elaborated observations, results of inspection through advanced equipment should complement the forms to give a comprehensive account of the conditions of the inspected trees. Greening, Landscape and Tree Management Section 34

5.2 TEMPLATES Templates control the overall look and layout of any required messages to facilitate communication within each department and with stakeholders and interest groups. They contain essential information / elements of common interest. 5.2.1 Reporting From time to time, there are cases that draw media and / or public attention and written reports apart from tree inspection records are essential to enhance public understanding of the situation. Written reports produced under these situations should be comprehensive, concise, convincing and conclusive. The format of reporting should make reference to the ANSI A300 (Part 9) 2011 Tree Risk Assessment, Section 93.6.2.1. This should be the minimum standard adopted by all inspection and endorsement officers. It is the responsibility of such officers to provide a well-planned and considered report. The content should be thorough in its investigation and assessment; quantifiable in data and completeness in facts and documentation. Identification and location of the specified tree(s); A description of the methods used; Tree risk assessment data; Recommendations for mitigating risk or additional assessments; and Recommendations for monitoring and follow-up. Greening, Landscape and Tree Management Section 35

5.2.2 Signs and Notices Display of signs and notices on site are useful for communication with the local community and enhances transparency of departments work on specific trees. They also serve as visual reminders to the general public on hazards that may be associated with the trees. Some suggested examples are provided below: Warning sign on pest treatment Notice on tree hazard and removal Greening, Landscape and Tree Management Section 36

5.3 CHECKLISTS Good checklists can help develop work planning by allowing you to check each item off as the work plan is developed. It provides record and aids the management in ensuring that all aspects of the work and / or processes are considered. The following checklists are provided for your use. # Content 1 Equipment / Tools and Personal Protective Equipment for Tree Inspection 2 Photographic Documentation for Tree Risk Assessment 3 Emergency Response 4 Sensitivity Analysis 5 Tree Removal (non-emergency situation) Greening, Landscape and Tree Management Section 37

5.3.1 Checklist: Equipment / Tools and Personal Protective Equipment for Tree Inspection Equipment / Tools and Personal Protective Equipment for Tree Inspection I. Equipment / Tools Camera Mallet Binoculars Diameter tape / Tape measure / Tapeline Notepad and Stationery Hand spade (Optional) Probe (Optional) Gloves (Optional) Shoe covers (Optional) Clinometer (Optional) Magnifying glass (Optional) Portable flashlight (Optional) Note Equipment shall be kept clean and maintained in good condition. Equipment that has been in contact with confirmed / suspected Brown Root Rot infected trees should be disinfected immediately after operation. Gloves and shoe covers should be disinfected or properly disposed after use. Greening, Landscape and Tree Management Section 38

Equipment / Tools and Personal Protective Equipment for Tree Inspection II. Personal protective equipment (PPE) Clothing and footwear appropriate for work condition and weather Drinking water First-aid kit Hard hat / Helmet Reflective vest Sun glasses (Optional) Sun screen (Optional) Insect repellent (Optional) Responsibilities Employers have duties on guidance, training and supervision with respect to use of PPE. They should ensure that their employees know why and when PPE is used, its maintenance or replacement schedule and limitations. They should regularly monitor proper use of PPE and thoroughly investigate causes of any non-compliance in using PPE. Appropriate and regular reminder to employees to use PPE is necessary, such as job briefing, signs posted on work sites etc. Enquiries For enquiries about occupational health and hygiene matters, you may contact the Labour Department's Occupational Safety and Health Branch through: Telephone: 2852 4041 Fax: 2581 2049 Email: enquiry@labour.gov.hk. Information on the services offered by the Labour Department and on major labour legislation can also be found on website at http://www.labour.gov.hk. Greening, Landscape and Tree Management Section 39

5.3.2 Checklist: Photographic Documentation for Tree Risk Assessment I. General Photographic Documentation for Tree Risk Assessment All photos are illustrated with dates. All photos are coloured. Proper annotations and descriptions are provided. For record of remedial measures, photos should be taken from similar view angles and clearly show the tree condition before and after the operation. All photos are taken in a specific manner to reflect the change of the tree groups or the individual trees when comparing to the relevant and retrievable records. II. Form 1 Overall views showing the tree group and its adjacent site conditions. Closer views of the tree group from different angles clearly showing its conditions. Views showing site conditions or changes that may have an impact on tree health or structural conditions. Views showing the potential impact on targets / sensitivity in case of tree failure. Views clearly showing tree health and structural conditions, in particular for stand-alone trees and street trees, are captured as far as practicable. Close-up views clearly showing trees having notable arboricultural defects, disorders or anomalies (if any). Greening, Landscape and Tree Management Section 40

III. Form 2 Photographic Documentation for Tree Risk Assessment A. Overall Condition Overall views showing the tree from different angles, its adjacent site condition and extent of leaning (if applicable). Views showing site conditions or changes that may have an impact on tree health or structural conditions. Views showing the potential impact on targets / sensitivity in case of tree failure. B. Crown Condition Views showing general conditions of the crown to illustrate the vigour, foliage density and colour. Close up views for crown defects. C. Trunk and Branch Condition Views showing general conditions of the trunk(s) and major branches illustrating the structural integrity. Close up views for trunk and / or branch defects. D. Lower Trunk / Root Condition Views showing general conditions of the root flare and disturbance that may damage the root zone. Close up views of lower trunk and / or root defects. Greening, Landscape and Tree Management Section 41

5.3.3 Checklist: Emergency Response A. Actions Emergency Response Call 999 immediately for tree failure incident involving loss of human life or major injury (where the injured person is admitted or is to be admitted to hospital). Check on the damage, stability and potential hazard of remaining tree (if any) poses to the public. Temporarily fence off the tree failure area. B. Communication Follow departmental protocol and notify GLTMS immediately without any delay when there is loss of human life or major injury. Follow departmental protocol and notify GLTMS as soon as possible in the case of substantial damage to properties, serious / complete blockage to major pedestrian / vehicular route(s). For typhoon signal no. 8 or above, report to GLTMS on the total of trees damage within 72 hours after the signal is lowered. C. Relevant Documentation Take full photographic records of the tree(s) concerned before removal. Tree Failure Report to GLTMS. Greening, Landscape and Tree Management Section 42

5.3.4 Checklist: Sensitivity Analysis A. Actions Sensitivity Analysis Report to the departmental directorate level of the tree management department on the proposed removal of sensitive trees. Explore alternative options for mitigation measures. Directorate level officer to validate tree removal proposal and options of mitigation measures; and evaluate reporting requirements to address public concern on the tree removal proposal. B. Communication Consult GLTMS on the proposed mitigation measures. Involve other relevant professionals for further site inspection or review on alternative mitigation measures if necessary. If tree removal is still considered necessary, engage concerned stakeholders in communication prior to commencement of any tree works. Prepare proactive response to stakeholders in the community. C. Relevant Documentation Tree Risk Assessment Forms (i.e. Form 1 and 2). Tree Risk Assessment reports, e.g. tree inspection reports by resistography or sonic tomography. Records of mitigation measures. Previous maintenance records. Compliance with reporting requirements and standards. Greening, Landscape and Tree Management Section 43

5.3.5 Checklist: Tree Removal (non-emergency situation) A. Actions Tree Removal (non-emergency situation) Check for blanket approval from LandsD to process Tree Preservation and Removal Proposal (TPRP). For departments with blanket approval, the proposal should be reviewed by internal tree works vetting mechanisms. For departments without blanket approval, approval from LandsD should be obtained before the tree removal works is performed. B. Relevant Documentation TPRP as required by relevant DEVB s technical circular. Greening, Landscape and Tree Management Section 44

Appendix 1 - Work Examples of Demarcation of Tree Risk Management Zone 1. Example One - AFCD case: Shing Mun Country Park Step 1: Desktop Demarcation Step 2 How to delineate tree risk management zones in this extensive area? Step 3 Delineated Cat I Zone Picnic areas with facilities Areas with frequent visitors as prominent targets Greening, Landscape and Tree Management Section A1-1

Step 4 Step 5 Greening, Landscape and Tree Management Section A1-2

2. Example Two - LCSD case: Kowloon Park and pavements along Nathan Road, Tsim Sha Tsui Step 1: Desktop Demarcation Step 2 Greening, Landscape and Tree Management Section A1-3

3. Example Three - HD case: Lei Muk Shu Estate, Kwai Chung Step 1: Desktop Demarcation Step 2 Greening, Landscape and Tree Management Section A1-4

Step 3 Step 4 Greening, Landscape and Tree Management Section A1-5

4. Example Four - WSD case: Tsuen Wan No.2 Fresh Water Service Reservoir, Kwai Chung Step 1: Desktop Demarcation Step 2 Greening, Landscape and Tree Management Section A1-6

Guidelines for Tree Risk Assessment and Management Arrangement (8th Edition) 5. Example Five - HyD case: A site along Tuen Mun Road Step 1: Desktop Demarcation Boundary of Tuen Mun Road Step 2 Greening, Landscape and Tree Management Section A1-7

Step 3 Step 4 Areas within expressway boundary and highway registered slopes Greening, Landscape and Tree Management Section A1-8

6. Example Six - CEDD case: A construction site As a general principle, the party maintaining the tree when risk assessment is required should be responsible for undertaking the tree risk assessment. Therefore, the party being either the project proponent or its works agent of a construction site, which should be responsible for the maintenance of the trees located within the Works Site no matter whether there are Temporary Government Land Allocation or not, should also be responsible for undertaking tree risk assessment of these trees. After construction, if a works department is still maintaining a tree during the establishment period or the aftercare period for OVTs, the works department concerned should be responsible for the tree risk assessment. If a tree has been handed over to the maintenance department for long-term maintenance after construction, the maintenance department concerned should then be responsible for the tree risk assessment. Trees in construction sites may be subject to higher stress than normal due to changes in their environmental conditions (e.g. changes in water table levels, dust, vibration, soil compaction, etc.). Therefore, more frequent (e.g. monthly) risk assessment should be conducted in the initial stage of the operation phase of the new development. Greening, Landscape and Tree Management Section A1-9

Area Basis Guidelines for Tree Risk Assessment and Management Arrangement (8 th Edition) Appendix 2 - Overall Workflow of Tree Risk Assessment and Management Arrangement TRIAGE - Black Dead trees Non-OVTs confirmed with BRR disease infection BLACK Actions and Monitoring Requirements for TRIAGE - BLACK 1. Tree removal within 4 weeks after completion of Form 1 inspection; or 2. If removal cannot be completed in 4 weeks, departments have to provide appropriate temporary mitigation measures as far as practicable to ensure public safety. 3. For non-ovts confirmed with BRR disease infection, a) Undertake Form 2 assessment every 3 months to monitor the tree condition until the removal of the tree; and b) Upload the tree information to the Tree Register. Form 1: Tree Group Inspection TRIAGE - Red OVTs confirmed with BRR disease infection Mature trees with individual trunk(s) over 750 mm DBH / OVTs / stonewall trees with crown spread within dripline of confirmed BRR infected tree Mature trees with individual trunk(s) over 750 mm DBH / OVTs / stonewall trees having one or more of the following major structural defects or health problems: (i) Open cavity on trunk having the longest axis 1/3 trunk diameter (ii) Co-dominant trunk with included bark / decay / cavity / split in the union (iii) Decay / damage with more than 120 degree in the root flare (iv) Over 20% die-back of crown (v) Presence of wood decay fungi at trunk and/or root zone within dripline RED Actions and Monitoring Requirements for TRIAGE - Red 1. Undertake Form 2 assessment and complete appropriate mitigation measures within 6 weeks as far as practicable after completion of Form 1 inspection; and 2. Close monitoring by Form 2 assessment: a) Every 3 months for BRR infected OVTs, b) Every 6 months for remaining Red category trees; and 3. Upload the tree information to Tree Register; and 4. Undertake emergency inspection within 7 calendar days as far as practicable after the lowering of: a) Typhoon Signal No. 8 or above; and b) Red or Black Rainstorm Signal. The emergency inspection should focus on the damage, stability and potential hazard that the tree poses to the public. TRIAGE - Yellow Mature trees with individual trunk(s) over 750 mm DBH / OVTs / stonewall trees that are not classified in Black and Red category Trees other than TRIAGE Black, Red or Yellow in Category I Zone Trees on complaint list with structural or health problems; Trees belonging to species with brittle wood structure and having unsatisfactory health or structural conditions with failure potential; Trees with major defects or health problems; Trees growing in very stressful site conditions with failure potential. Risk not mitigated YELLOW Remedial action Form 2: Individual TRA Risk mitigated Actions and Monitoring Requirements for TRIAGE - Yellow 1. Undertake Form 2 assessment and provide appropriate mitigation measures for OVTs and stonewall trees; and 2. Undertake appropriate mitigation measures for mature trees with individual trunk(s) over 750mm DBH having structural defects or health problems; and undertake Form 2 assessment if necessary. 3. Undertake Form 2 assessment and provide appropriate mitigation measures for mature trees with individual trunk(s) over 750mm DBH that have no visible structural defects or health problems if resources permit. The Form 2 assessment and associated mitigation measures can be completed by 31 October every year. 4. For OVTs and stonewall trees, a) Undertake Form 2 assessment every 6 months; and b) Upload the tree information to Tree Register. Monitoring Requirements Monitoring and keep record by Form 1 Mitigation and Monitoring Requirements Corrective / risk abatement measures; and Monitoring and keep record by Form 2 Departmental audit inspection / GLTMS audit Greening, Landscape and Tree Management Section, A2-1

Appendix 3 - Requirements for Inspection Officers and Endorsement Officers (Form 1) Inspection Officer and Endorsement Officer for Forms 1 shall meet the following minimum requirements on both training / academic / professional qualification AND work experience:- Certificate / diploma in arboriculture or equivalent to the standards of Level 3 or 4 in the Hong Kong Qualifications Framework, such as: Training/ Academic/ Professional Qualification - Professional Diploma Programme in Arboriculture or Tree Risk Assessment and Management of the School of Continuing and Professional Studies, Chinese University of Hong Kong (CUSCS), - Advanced Diploma in Tree Management and Conservation of the School of Professional and Continuing Education, University of Hong Kong (HKU SPACE), - Certificate in Professional Tree Management of the Open University of Hong Kong (OUHK), - Professional Diploma in Horticulture and Landscape Management of the Technological and Higher Education Institute of Hong Kong (THEi), - Higher Diploma in Conservation and Tree Management of the Vocational Training Council (VTC), and - Diploma / Certificate in Arboricultural Management conducted by the training bodies of the Employees Retraining Board (ERB), etc. OR Certified Arborist, Certified Arborist Utility Specialist, Certified Arborist Municipal Specialist or Board Certified Master Arborist of the International Society of Arboriculture; or Technician Member, Professional Member or Fellow of the Arboricultural Association of the UK; or European Tree Technician of the European Arboricultural Council; or General Member of the National Arborists Association of Australia (issued on or before31 Dec 2010); or Registered Qualified Arborist, Registered Practicing Arborist, Registered Consulting Arborist or Registered Consulting & Practicing Arborist of Arboriculture Australia; or Accredited Arboricultural Practitioner of the Hong Kong Institute of Landscape Architects or equivalent. OR Completed and passed Comprehensive Tree Risk Assessment and Management Training Course with assessment or Refresher Course with assessment organised by the Tree Management Office (TMO); or Completed and passed equivalent departmental training recognised by the TMO; or Completed and passed training programmes in tree risk assessment recognised by the TMO, such as Tree Risk Assessment Qualification by the International Society of Arboriculture, Professional Tree Inspection by Lantra Awards or Certificate in Tree Preservation and Risk Assessment conducted by the training bodies of the Employees Retraining Board (ERB). AND Work Experience Has at least 2 years of work experience in tree care and is familiar with tree risk assessment / management. Greening, Landscape and Tree Management Section A3-1

Tree Management Information System (TMIS) 樹 木 管 理 資 訊 系 統 Tree Risk Assessment Form 1 : Tree Group Inspection 樹 木 風 險 評 估 表 格 1 : 樹 群 檢 查 General Information 基 本 資 料 1 # 1 0 Dept. 部 門 / Agency 機 構 : # Inspection Officer 巡 查 人 員 : Post 職 位.. 1 # 1 0 File Ref. 檔 案 編 號 : # Endorsement Officer 覆 核 人 員 : Post 職 位.. Date of Inspection 巡 查 日 期 : Last Inspection Date 上 次 巡 查 日 期 : ## 1 Agency 機 構 / Project 工 程 / Contract No. 合 約 編 號 Inspection Frequency 巡 查 週 期 : Location Information 位 置 資 料 Master Zone Departmental Ref. 主 區 編 號 : # 1 # Sub Zone Departmental Ref. 副 區 編 號 : # 0 English Location 英 文 地 點 : # 1 # Chinese Location 中 文 地 點 : Tree Risk Management Zone 樹 木 風 險 管 理 地 點 類 別 : category I 第 一 類 category II 第 二 類 category III 第 三 類 Nearby Utility Post No 就 近 公 用 設 施 編 號 : Location Types 地 點 類 別 : (multiple answers allowed 可 選 多 於 一 項 ): Roadside Landscaped Area 路 旁 綠 化 地 區 Central Divider 中 央 分 隔 帶 Tree Pit 樹 穴 Village Environs 鄉 村 範 圍 Public Park/Recreation Venue 公 園 / 康 樂 場 地 Remote Countryside 偏 遠 # 郊 0區 Vacant Government Land # 政 0 府 空 置 土 地 Others (please specify) 其 他 ( 請 說 明 ): Unallocated Government Land 未 撥 用 的 政 府 土 地 Recreational Site/Facilities inside Country Park 郊 野 公 園 內 康 樂 用 地 或 設 施 SIMAR Slopes 系 統 性 鑑 辨 維 修 責 任 的 斜 坡 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Tree Information 樹 木 基 本 資 料 The size of a tree group should be defined by location types, such as public park, SIMAR slopes, tree pits, etc. with due consideration given to the limitations of visual tree assessment. 在 決 定 樹 群 的 大 小 時, 應 參 照 地 點 類 別, 如 公 園 系 統 性 鑑 辨 維 修 責 任 的 斜 坡 樹 槽 等, 並 需 考 慮 目 測 法 的 局 限 Main tree species in the group (DBH 95 mm) and minority tree species of significant size (i.e. approx. DBH 300 mm) App. No. Height (m) Height (m) Overall Health Overall 在 群 組 內 的 主 要 樹 種 ( 胸 徑 95 毫 米 ) 及 樹 幹 胸 徑 或 高 度 或 of Trees From: To: Condition Structural 樹 冠 範 圍 較 大 的 樹 種 ( 即 胸 徑 約 300 毫 米 ) 大 約 樹 木 樹 高 ( 米 ) 樹 高 ( 米 ) 整 體 健 康 狀 況 Condition 數 量 由 至 整 體 結 構 狀 況 (Please delete the "blank" rows before save 保 存 之 前, 請 刪 除 空 白 行 ) Total No. of Trees 樹 木 總 數 : No. of rows to be added: Add Row Delete Row Overall Remarks 整 體 評 語

Target 目 標 Target (people or property potentially affected by tree/branch failure) 目 標 ( 因 樹 木 倒 塌 或 枝 條 斷 裂 而 受 影 響 的 人 或 財 產 ) Does target Exist? 目 標 物 是 否 存 在? Can target be moved? 能 否 移 除 目 標 物? Can the use of site be restricted? 可 否 限 制 場 地 的 使 用? Frequency of use of location 使 用 該 地 點 的 頻 密 程 度 : Yes / 是 Yes / 是 Yes / 是 No / 否 No / 否 No / 否 Occasional Use Intermittent Use Frequent Use Constant Use 偶 爾 使 用 間 歇 使 用 經 常 使 用 恆 常 使 用 Identification of Trees for Remedial Action or Detailed Tree Risk Assessment (Form 2) 識 別 樹 木 以 採 取 風 險 緩 減 措 施 或 進 行 詳 細 樹 木 風 險 評 估 ( 表 格 2) Trees falling under the following criteria 樹 木 屬 於 以 下 任 何 一 項 或 多 於 一 項 類 別 (1) Old and Valuable Tree (OVT) 古 樹 名 木 Number of trees 樹 木 數 量 Remedial action or detailed tree risk assessment (Form 2) 緩 減 措 施 或 詳 細 的 樹 木 風 險 評 估 ( 表 格 2) Anticipate Completion Date 預 計 完 成 日 期 Actual Completion Date 完 成 日 期 (2) Stonewall tree 石 牆 樹 (3) Trees on complaint list with structural or health problems 投 訴 個 案 中 有 結 構 或 健 康 問 題 的 樹 木 (4) Trees belonging to species with brittle wood structure and having unsatisfactory health or structural conditions with failure potential 屬 木 質 脆 弱 品 種 而 健 康 或 結 構 欠 佳 的 而 具 倒 塌 風 險 的 樹 木 (5) Tree with major defects or health problems 有 明 顯 缺 陷 或 健 康 問 題 的 樹 木 (6) Trees growing in very stressful site conditions with failure potential 生 長 於 非 常 擠 壓 環 境 的 樹 木 並 有 樹 枝 或 樹 幹 倒 塌 風 險 (7) Mature trees 已 屆 成 熟 樹 齡 Attached Information 附 夾 資 料 (Maximum 10 attachments and total 25MB allowed 最 多 可 容 納 10 個 附 件 並 合 計 不 多 於 25MB) 1 Site Plan 場 地 平 面 圖 (Provide at least 1 site plan 最 少 提 供 一 個 場 地 平 面 圖 ) Description 說 明 : Add Site Plan Delete Site Plan 1 Photo Record 樹 木 照 片 (Provide at least 1 photo record 最 少 提 供 一 個 相 片 紀 錄 ) Description 說 明 : Add Photo Record Delete Photo Record Other Attachments 其 他 附 件 (Please specific 請 註 明 ) Add Others Delete Others 1 Subject Title 標 題 : Description 說 明 : Note 注 意 : Please read in conjunction with TMO s Guidelines on Tree Risk Assessment and Management Arrangement and relevant Technical Circulars promulgated on website www.trees.gov.hk 請 參 閱 發 展 局 網 頁 www.trees.gov.hk 樹 木 管 理 辦 事 處 的 樹 木 風 險 評 估 安 排 及 管 理 指 引 及 相 關 技 術 通 告 DEVB TMIS TRA Form1 (Nov 2015)

Appendix 5 - Explanatory Notes for Form 1 1. General Information The Inspection Officer shall make reference to the previous tree inspection records, if available, to help to identify changes in the site conditions and tree conditions. 1.1 Inspection Officer and Endorsement Officer The Inspection Officer usually is the frontline staff member who conducts the Form 1: Tree Group Inspection. For outsourced tree inspection works, the consultant / contractor staff can serve as the Inspection Officer to conduct the inspection. The Endorsement Officer is the supervisory / managerial staff at a rank higher than that of the Inspection Officer who oversees the Tree Group Inspection process. For outsourced tree inspection works, the supervisory / managerial staff of the consultant / contractor firm can serve as Endorsement Officer. Inspection Officer and Endorsement Officer for Form 1 need to meet the requirements on both training / academic / professional qualification and work experience as listed in Appendix 3. 2. Location Information This information is self-explanatory. Additional information that may help to identify the tree group location, such as lamp post number, registered slope number, other prominent landmarks nearby, etc., can be recorded under the field of Others. 3. General Tree Information 3.1 Number of Trees Covered by a Form 1 In general, each tree group should contain no more than 50 trees in sites with reasonable accessibility. For trees subject to site constraint such as growing on a vegetated slope, each tree group should in principle contain no more than 100 trees. If there are site constraints, the number can be adjusted to suit the physical boundary (e.g. surface channel or maintenance access) on site on an exceptional basis. Practical difficulties for adopting large tree group size over 100 trees in a Form 1 should be explicitly stated in the remarks of the form. Greening, Landscape and Tree Management Section A5-1

For departments with individual assessment for each and every tree in detail, the tree group size covered in each form can be larger than the recommended tree group size to suit physical condition of the site such as slope areas and building platform areas. The recommended tree group size does not apply to Category III zone. 3.2 Tree Species Provide an indicative description of the diversity and distribution of dominant tree species in the group (diameter at Breast Height (DBH) 95mm) and minority tree species of significant size (i.e. approximately DBH 300mm). 3.3 Approximate Number of Trees Record the approximate quantity (in number) of each tree species in the tree group. 3.4 Range of Tree height Indicative description of tree height of each specified tree species. 3.5 Overall Health Condition and Overall Structural Condition Record the overall health and structural conditions of each specified tree species. Refer to Pictorial Guide for Tree Maintenance to Reduce Tree Risks (http://www.trees.gov.hk/filemanager/content/attachments/pictorialguidefort reemaintenancetoreducetreerisk(eng).pdf) for reference on tree defects. 3.6 Other Remarks Categorisation of the TRIAGE system (if any) and additional information on trees which require further attention should be recorded to facilitate identification of appropriate follow-up action and future monitoring. The structural defects or health problems of an individual tree should be described in the column and recorded with location marked on plan. Adequate photo records should be taken in accordance to the Photo-Taking Guidelines for Tree Risk Assessment in Appendix 6. Greening, Landscape and Tree Management Section A5-2

4. Target Targets are people, property, or human activities that could be injured, damaged, or disrupted by a tree failure within the Tree Fall Zone (TFZ). The possible Tree Fall Zone (TFZ) is defined as 1.5 times of the height of a tree. The TFZ should be adjusted according to the angle of the lean of a tree and site conditions (e.g. the gradient of the slope where the tree is located). 4.1 Does target exist? The Inspection Officer should consider if any target exists within the target area of the tree group. 4.2 Can targets be moved? For example, a picnic table beneath a defective tree inside a country park can be moved to other areas to minimise the presence of targets near the tree. 4.3 Can the use of the site be restricted? For example, fencing off the site to avoid presence of targets beneath the tree. 4.4 Frequency of use of the location Constant use For example, presence of a house next to a tree represents constant use as the house is static. A pavement along Nathan Road with very busy pedestrian and vehicular flow is also considered under constant use. Frequent use For example, parks with regular visitors are of frequent use. Intermittent use A recreational cycling path used intermittently is an example. Occasional use Maintenance path with restricted access and limited to use by the maintenance party is an example. Greening, Landscape and Tree Management Section A5-3

5. Identification of Trees for Remedial Action or Detailed Tree Risk Assessment (Form 2) During the tree group inspection (Form 1), it is essential to identify potential tree hazards so that remedial action or detailed tree risk assessment (using Form 2) for the trees concerned can be carried out in a timely manner. The identification process should cover trees under TRIAGE system in Section 2.4.1 (a) of Part 2 in the Guidelines for TRAM Arrangement and trees as described in the following Section 5.1 to 5.6. 5.1 Old and Valuable Trees (OVTs) and Stonewall Trees All OVTs should be covered by a detailed tree risk assessment using Form 2, irrespective of the tree size. For stonewall trees, those with a tree diameter at breast height, measured at 1.3m from the trunk base on the wall, 95mm or more should be covered by a detailed tree risk assessment using Form 2. 5.2 Trees on Complaint List with Structural or Health Problems Detailed tree risk assessment is required only for outstanding tree complaints related to structural or health problems. It is not mandatory to conduct a detailed tree risk assessment for a tree under complaint if remedial action has already been taken or will be taken immediately to alleviate / eliminate the potential risk. 5.3 Trees Belonging to Species with Brittle Wood Structure and having Unsatisfactory Health or Structural Conditions with Failure Potential Some tree species have brittle wood structure which makes them more prone to branch or trunk failure. These species include Delonixregia ( 鳳 凰 木 ), Erythrina variegata ( 刺 桐 ), Alstonia scholaris ( 糖 膠 樹 ), Aleurites moluccana ( 石 栗 ), Celtis sinensis ( 朴 樹 ) and Senna siamea ( 鐵 刀 木 ). Trees species with brittle wood structure but of a smaller mature size such as Hibiscus tiliaceus ( 黄 槿 ) and Bauhinia x blakeana ( 洋 紫 荊 ) are not classified under this category. It is not mandatory to conduct detailed tree risk assessment for a tree species of a mature size with brittle branches if no obvious defect that will promote failure is observed. The objective of highlighting this criterion is to remind Inspection Officers to pay special attention to tree defects of the concerned species and consider whether a detailed assessment using Form 2 is required for monitoring purpose. Greening, Landscape and Tree Management Section A5-4

Guidelines for Tree Risk Assessment and Management Arrangement (8th Edition) 5.4 Trees with Major Defects or Health Problems Refer to Pictorial Guide for Tree Maintenance to Reduce Tree Risks (http://www.trees.gov.hk/filemanager/content/attachments/pictorialguidefort reemaintenancetoreducetreerisk(eng).pdf) and criteria of the Red category in the TRIAGE System for reference on tree defects. The information on common wood decay fungi and Brown Root Rot (BRR) disease is available in the GLTMS website (http://www.trees.gov.hk/en/home/index.html) and the intranet under Cyber Manual for Greening (http://devb.host.ccgo.hksarg/en/treerisk/index.html). If the defects / health problems are of a minor nature, it may not be necessary to conduct a detailed tree risk assessment. If the identified defects or health problems can be rectified with immediate follow-up measures, for example, removal of hangers and dead branches, to alleviate the potential risk, it would not be necessary to conduct a detailed tree risk assessment. In case of doubt, we recommend to conduct a Form 2 tree risk assessment on the subject tree to determine the required risk attenuation action. 5.5 Trees Growing in Very Stressful Site Conditions with Failure Potential Stressful site conditions may weaken the tree health and / or structural condition which can increase the failure potential. (a) Confined Growing Area For example, shotcreted slopes or concrete footpaths where tree roots are severely restricted by concrete. Trees in tree pits surrounded by permeable flexible paving may be excluded from this category. Greening, Landscape and Tree Management Section A5-5

(b) Trees under Cover or Low Headroom For example, trees under building canopies or footbridges where space for tree crown extension is limited. Limited headroom for tree growth Apart from assessing the health condition / structural stability of these trees and identifying appropriate remedial actions, consideration should be given to formulate measures that can effectively relieve the stressful site conditions (e.g. expand the tree planter, transplant the tree, remove the clutter under the tree, etc.) subject to consideration of the site conditions and detailed tree inspections. 5.6 Mature Trees Trees other than Old and Valuable Trees and stonewall trees with an individual trunk(s) over 750mm in DBH and do not fall into any categories of Section 5.1 to 5.5 described in above. Refer to Management Guidelines for Mature Trees (http://www.trees.gov.hk/filemanager/content/attachments/paper_mature_tree s_(finalised_and_issued).pdf) for definition of mature tree. 5.7 Remedial Action or Detailed Tree Risk Assessment (Form 2) Location of the trees requiring remedial action or detailed tree risk assessment (Form 2) should be marked on plan. The extent and type of remedial works on the trees should be clearly described with photos showing the conditions before and after the operation should be taken from similar view angles as far as practicable to facilitate comparison. The records of maintenance operations should be properly documented. Greening, Landscape and Tree Management Section A5-6

5.8 Anticipated Date of Completion Record the anticipated date of completion for the works to be carried out for necessary monitoring, record and audit purpose. 6. Attached Information 6.1 Site Plan Tree Group Inspection Area An example of a site plan 6.2 Photo Record The completed Form 1 should be accompanied by photographic record showing an overview of the tree group inspection site and diagnostic features of the tree defects observed to facilitate follow-up action on tree problems, and for audit as well as future monitoring and reference. Sample photos are shown below. Photo no.1 - Site condition Greening, Landscape and Tree Management Section A5-7

Photo no.2 Ficus hispida to be removed Please also refer to the Guidelines on Photo-Taking for Tree Risk Assessment in Appendix 6 for the detailed requirements. If the tree species cannot be identified on site, the Inspection Officer can take photos of the tree(s) and seek professional assistance afterwards. The Inspection Officer may use supplementary sheets to record the details of the tree species under assessment. 6.3 Others Other observations requiring follow up actions such as overgrown ground vegetation near root flare / trunk base requiring clearance by the management department or agent to facilitate root collar / trunk base inspection have to be explicitly recorded. Greening, Landscape and Tree Management Section A5-8

Appendix 6 - Photo-taking Guidelines for Tree Risk Assessment 1. General All photographs should be illustrated with the dates of the photographs were taken. The photo records should be coloured photos clearly showing the tree conditions. Proper annotations and descriptions should be provided to illustrate the conditions of trees. For record of remedial mitigation measures, photos showing the conditions before and after the operations should be taken from similar view angles as far as possible to facilitate comparison. All photographs should be taken in a specific manner so as to provide a fair comparison and clear illustration to reflect the change of the tree groups or the individual trees when compared to the relevant and retrievable records. 2. Photo Records in Form 1 2.1 Overall condition Overall view showing the tree group and its adjacent site conditions. Close views of the tree group from different angles clearly showing its condition. Views showing site conditions or changes that may have an impact on tree health or structural conditions. Views showing the potential impact on targets / sensitivity in case of tree failure. Views clearly showing tree health and structural conditions, in particular for stand-alone trees and street trees, should be captured as far as practicable unless tree parts are obscured due to site constraints (such as those on steep slopes or trees in clusters). A photo can cover more than one tree if it can capture the general conditions of individual trees. Close-up views clearly showing trees having notable arboricultural defects, disorders or anomalies (if any). Greening, Landscape and Tree Management Section A6-1

3. Photo Records in Form 2 3.1 Overall Condition Overall views showing the tree from different angles, its adjacent site condition and extent of leaning (if applicable). Views showing site conditions or changes that may have an impact on tree health or structural conditions. Views showing the potential impact on targets / sensitivity in case of tree failure. 3.2 Crown Condition Views showing general condition of the crown to illustrate the vigor, foliage density and colour. Close up views for the following features (if any): - abnormal leaf size with reference scale; - dieback twigs; - epicormics; - signs of pest or disease; and - other notable arboricultural defects or disorders. 3.3 Trunk and Branch Conditions Views showing general conditions of the trunk(s) and major branches illustrating the structural integrity. Close up views for the following features (if any): - co-dominant trunks or branches; - poor taper; - included bark or weak attachment; - decay or cavity; - cracks or splits; - wounds and wound wood development; - dead branches or hangers; - crook or abrupt bends; - crossed branches; - heavy lateral limb; - lion tailing; - bleeding or sap flow; - fungal fruiting bodies; Greening, Landscape and Tree Management Section A6-2

- parasitic plants; - signs of pests and diseases; and - other notable arboricultural defects or disorders. 3.4 Lower Trunk / Root Condition Stressful site conditions, including construction activities within the tree protection zones and any other activities or restrictions that may damage the root system and the overall structural stability of the trees. Views showing general conditions of the root flare and disturbance that may damage the root zone. Close up views of the following features (if any): - root rot; - exposed roots; - girdling roots; - cracks or splits; - mechanical damage; - root-plate movement; - soil cracks or other cracks; - fruiting bodies; - signs of pests and disease; and - other notable arboricultural defects or disorders Greening, Landscape and Tree Management Section A6-3

Appendix 7 - Requirements for Inspection Officers and Endorsement Officers (Form 2) a) Requirements of Inspection Officer Inspection Officer for Form 2 assessment shall meet the following minimum requirements on academic / professional qualification AND training AND work experience:- Academic/ Professional Qualification Certificate / diploma in arboriculture or equivalent to the standards of Level 3 or 4 in the Hong Kong Qualifications Framework, such as: - Professional Diploma Programme in Arboriculture or Tree Risk Assessment and Management of the CUSCS, - Advanced Diploma in Tree Management and Conservation of the HKU SPACE, - Certificate in Professional Tree Management of the OUHK, - Professional Diploma in Horticulture and Landscape Management of the THEi, - Higher Diploma in Conservation and Tree Management of the VTC, and - Diploma / Certificate in Arboricultural Management conducted by the training bodies of the ERB, etc. OR Certified Arborist, Certified Arborist Utility Specialist, Certified Arborist Municipal Specialist or Board Certified Master Arborist of the International Society of Arboriculture; or Technician Member, Professional Member or Fellow of the Arboricultural Association of the UK; or European Tree Technician of the European Arboricultural Council; or General Member of the National Arborists Association of Australia (issued on or before 31 Dec 2010); or Registered Qualified Arborist, Registered Practicing Arborist, Registered Consulting Arborist or Registered Consulting & Practicing Arborist of Arboriculture Australia; or Accredited Arboricultural Practitioner of the Hong Kong Institute of Landscape Architects or equivalent; AND Training Completed and passed Comprehensive Tree Risk Assessment and Management Training Course with assessment or Refresher Course with assessment organised by the TMO; or Completed and passed equivalent departmental training recognised by the TMO; or Completed and passed training programmes in tree risk assessment recognised by the TMO, such as Tree Risk Assessment Qualification by the International Society of Arboriculture, Professional Tree Inspection by Lantra Awards or Certificate in Tree Preservation and Risk Assessment conducted by the training bodies of the Employees Retraining Board (ERB); AND Work Experience Has at least 2 years of work experience in tree care and is familiar with tree risk assessment / management. Greening, Landscape and Tree Management Section A7-1

(b) Requirements of Endorsement Officer Endorsement Officer for Forms 2 assessment shall meet the following minimum requirements on both training / academic / professional qualification AND work experience:- Training/ Academic/ Professional Qualification Certificate / diploma in arboriculture or equivalent to the standards of Level 3 or 4 in the Hong Kong Qualifications Framework, such as: - Professional Diploma Programme in Arboriculture or Tree Risk Assessment and Management of the School of Continuing and Professional Studies, Chinese University of Hong Kong (CUSCS), - Advanced Diploma in Tree Management and Conservation of the School of Professional and Continuing Education, University of Hong Kong (HKU SPACE), - Certificate in Professional Tree Management of the Open University of Hong Kong (OUHK), - Professional Diploma in Horticulture and Landscape Management of the Technological and Higher Education Institute of Hong Kong (THEi), - Higher Diploma in Conservation and Tree Management of the Vocational Training Council (VTC), and - Diploma/Certificate in Arboricultural Management conducted by the training bodies of the Employees Retraining Board (ERB), etc. OR Certified Arborist, Certified Arborist Utility Specialist, Certified Arborist Municipal Specialist or Board Certified Master Arborist of the International Society of Arboriculture; or Technician Member, Professional Member or Fellow of the Arboricultural Association of the UK; or European Tree Technician of the European Arboricultural Council; or General Member of the National Arborists Association of Australia (issued on or before31 Dec 2010); or Registered Qualified Arborist, Registered Practicing Arborist, Registered Consulting Arborist or Registered Consulting & Practicing Arborist of Arboriculture Australia; or Accredited Arboricultural Practitioner of the Hong Kong Institute of Landscape Architects or equivalent; OR Completed and passed Comprehensive Tree Risk Assessment and Management Training Course with assessment or Refresher Course with assessment organised by the Tree Management Office (TMO); or Completed and passed equivalent departmental training recognised by the TMO; or Completed and passed training programmes in tree risk assessment recognised by the TMO, such as Tree Risk Assessment Qualification by the International Society of Arboriculture, Professional Tree Inspection by Lantra Awards or Certificate in Tree Preservation and Risk Assessment conducted by the training bodies of the Employees Retraining Board (ERB); AND Work Experience Has at least 2 years of work experience in tree care and is familiar with tree risk assessment / management. Greening, Landscape and Tree Management Section A7-2

Appendix 8 Guidelines for Tree Risk Assessment and Management Arrangement (8th Edition) Tree Management Information System (TMIS) 樹木管理資訊系統 Tree Risk Assessment Form 2 - Individual Tree 樹木風險評估表格2 : 個別樹木 1 General Information基本資料 Dept. 部門/ Agency 機構: Inspection officer 巡查人員: Post職位: File Ref. 檔案編號: Date of Inspection (dd/mm/yyyy) 巡查日期: Endorsement Officer 覆核人員: Post職位: Departments - HAD & L Last Inspection Date (dd/mm/yyyy)上次巡查日期: Entry for Date of Inspec Agency 機構/ Project 工程/ Contract No. 合約編號: Tree Risk Management Zone 樹木風險管理 地點類別: category I category II category III Inspection Frequency巡查週期: 0 Location Information 位置資料 # # 0 TRUE Tree ID (Dept. Ref.) 樹木編號(部門參考) Tree Species 樹木品種: Tree ID - breakdown wi Master Zone Departmental Ref. 主區編號: # Sub Zone Departmental Ref. 副區編號: # English Location 英文地點: Tree Species - add func Chinese Location 中文地點: Nearby Utility Post No 就近公用設施編號: Coordinates 座標 * (HK1980 GRID) Northing 坐標北 (Y) Easting 坐標東 (X) Is the tree on Tree Register? 是否樹木登記冊內樹木? Yes 是 Tree Register No. 樹木登記冊號碼: Location Types 地點類別: (multiple answers allowed 可選多於一項): Location - breakdown w Is the tree a Stone Wall Tree? 是否石牆樹? Yes 是 OVT No. 古樹名木: Roadside Landscaped Area 路旁綠化地區 Central Divider中央分隔帶 Public Park/Recreation Venue公園/康樂場地 Unallocated Government Land未撥用的政府土地 Remote Countryside偏遠郊區 Recreational Site/Facilities inside Country Park 郊野公園內康樂用地或設施 0 SIMAR Slopes系統性鑑辨維修責任的斜坡 Vacant Government Land政府空置土地 Others (please specify)其他 (請說明): 0 DBH of tree trunk(s)(mm) (1.3m above soil level) 每枝主幹胸徑(毫米) No. of Tree Trunk(s) (#) 主幹數目(#): #1 #2 #3 #4 Tree Pit樹穴 Village Environs鄉村範圍 #5 No. of trunk - set contro Aggregated DBH (mm) 總胸徑(毫米): 0 (離地面1.3米) Tree Spread(m) 樹冠闊度(米) : Tree Height(m)樹高(米) : Age Class 樹齡組別 : Young幼 GENERAL CONDITION 基本狀況 CROWN CONDITION 樹冠狀況 Foliage density葉片密度: Heavy crown load Co-dominant branches等勢枝 Severity of Defects - col Included bark 內夾樹皮 Severity of Defects - set Mature成熟 Senescent衰老 Severity of Defects 嚴重程度: BRANCH CONDITION 枝幹狀況 Severity of Defects - add Severity of Defects 嚴重程度: (multiple answers allowed 可選多於一項 ): Normal 正常 樹冠負荷太重: Sparse 稀疏 Yes是 No否 Cavities樹洞 Live crown ratio 活冠比: Cracks/splits 裂縫/裂開 Normal 正常 (foliage canopy / total height of tree) Wounds/Mechanical injury Chlorotic 萎黃 有葉的樹冠 / 樹高 Foliage colour葉片顏色 Brown (signs of wilting) 褐色 (呈現枯萎徵狀) Leaf Size 葉片大小 Normal 正常 Abnormal 不正常 低 < 40% 中 40-70% Dead branches/hangers High 高 > 70% Crooks/abrupt bends <5% crown 樹冠 Cross branches 疊枝 5-20% crown 樹冠 Heavy lateral limb 重側枝 21-50% crown 樹冠 枯死/懸吊斷枝 不常規彎曲 Dieback twigs枯枝: Epicormics 水橫枝: Yes是 明顯傷痕/機械破損 Low Medium No否 (please specify the location and severity >50% 請說明位置及嚴重程度 ) Lion s tailing獅尾 (excessive end weight on branch crown 樹冠 枝端過重 ) Bleeding/sap flow滲液 Crown reduced/excessively Tree vigor茁壯程度: Good 好 Average 良 Poor 差 Lean 傾斜 Yes是 thinned/ topped/ pollarded: 樹冠大幅減少 或削頂 或截頭 Yes是 No否 Parasitic/Epiphytic plants 寄生/附生植物 Yes是 No否 Asymmetric tree canopy 樹冠不對稱 (If yes please specify type 如有請說明種類 ) Yes是 0 No否 Signs of pests and disease No否 呈現病蟲害徵狀: 呈現病蟲害徵狀: Angle of lean from vertical 傾斜角度 Yes是 Natural due to phototropism/ self corrected 趨光性或已自然修正 0 (If yes please specify type 如有 請說明種類 ) 0 Others (please specify) : 其他( 請說明 ) 0 No否 N 如有請說明種類 ) 新近傾斜/根基不穩 Soil cracks or cracks in structure(s) behind lean 有土壤裂縫或 Yes是 No否 (If yes please specify type Recently tilted/unstable root- plate Defects of Signs of pest Signs of pests and disease N Others (please specify) : 其他( 請說明 ) 0 裂縫處於傾斜部位背後: Yes是 No否 Greening, Landscape and Tree Management Section, A8-1

TRUNK CONDITION Severity of ROOT CONDITION Severity of SITE CONDITION 主 幹 狀 況 Defects 根 部 狀 況 Defects 樹 木 生 長 環 境 (multiple answers allowed 嚴 重 程 度 : (multiple answers allowed 嚴 重 程 度 : (multiple answers allowed 可 選 多 於 一 項 ) : 可 選 多 於 一 項 ) : 可 選 多 於 一 項 ) : #1 Decay/Cavity * Root flare/collar not visible Site disturbed by construction Severity of Defects for T 腐 爛 / 樹 洞 (open 可 見 的 ) 根 脊 不 現 activities Length 長 : (mm) Root rot 根 部 腐 壞 鄰 近 環 境 受 工 程 影 響 : Width 闊 : (mm) Cracks/splits 裂 縫 或 裂 開 Road widening 道 路 擴 寬 Depth 深 : (mm) Cut/pruned roots Drain replacement 渠 道 重 鋪 根 部 經 切 割 或 截 根 Soil grade reduce/ increase #2 Decay/Cavity * Fungal fruiting bodies 地 表 上 升 或 下 降 腐 爛 / 樹 洞 (open 可 見 的 ) 呈 現 菌 類 子 實 體 Site clearing 地 盤 平 整 活 動 Length 長 : (mm) Dead surface roots Soil heaving 土 壤 脹 起 Width 闊 : (mm) 根 部 枯 萎 Laying of new footpath Depth 深 : (mm) Exposed root 根 部 外 露 鋪 設 行 人 道 Mechanical injury 機 械 破 損 Laying of underground utilities #3 Decay/Cavity * Termites/borers injury 鋪 設 地 下 設 施 腐 爛 / 樹 洞 (open 可 見 的 ) 白 蟻 或 蛀 心 蟲 蛀 蝕 New flower beds/ new lawn Length 長 : (mm) Root-plate movement below tree 在 樹 下 加 建 花 圃 / 草 坪 Width 闊 : (mm) 根 基 移 位 ### Others(specify) Depth 深 : (mm) Girdling roots 纏 繞 根 0 其 他 ( 請 說 明 ) # Rooting area restricted Soil condition 土 壤 情 況 Poor taper 不 良 漸 尖 生 長 根 部 伸 展 範 圍 受 限 制 : Sandy 沙 質 Codominant trunks 等 勢 幹 Yes 是 No 否 Clay 黏 土 Included bark 內 夾 樹 皮 (If yes pls specify type 如 有 請 說 明 ) Water logging 積 水 Cracks/splits 裂 縫 或 裂 開 Drain 渠 道 Soil compaction 土 壤 被 擠 壓 Abnormal bark crack Footpath/pavement 行 人 道 (restricted root growth area inside dripline 不 尋 常 樹 皮 裂 縫 Road curb 路 肩 於 滴 水 線 範 圍 內 有 障 礙 物 限 制 根 部 延 伸 ) Bulge 腫 脹 Retaining structure Yes 是 No 否 Fungal fruiting bodies 護 土 結 構 呈 現 菌 類 子 實 體 Footings or railings Exposed dead wood 地 基 或 攔 杆 枯 幹 外 露 Others (please specify) : < 25% 26-50% Wounds/Mechanical 其 他 ( 請 說 明 ) ## 51-75% >75% injury 明 顯 傷 痕 / 機 械 破 損 ## Width of Planting area 0 種 植 面 範 圍 Large wound/ crack/ < 1.2m 1.3-2m decay on circumference 2.1-3m 3.1-4m 大 範 圍 破 損 或 裂 縫 或 腐 爛 > 4m Bleeding /Sap flow 滲 液 Tree location with exposure to Signs of pests and Signs of pests and wind 樹 木 所 在 地 點 的 受 風 情 況 : disease 呈 現 病 蟲 害 徵 狀 : disease 呈 現 病 蟲 害 徵 狀 : Single tree 單 獨 一 棵 Yes 是 No 否 Yes 是 No 否 Tree with emergent canopy (If yes, please specify type (If yes, please specify type 樹 冠 層 以 上 如 有, 請 說 明 種 類 ) 如 有, 請 說 明 種 類 ) Edge of a group of trees ## 樹 群 邊 緣 Recently exposed 新 近 暴 露 0 Others (please specify) : ## Others (please specify) : ### Others (please specify) : others for root condition 其 他 ( 請 說 明 ) 0 其 他 ( 請 說 明 ) 0 其 他 ( 請 說 明 ) * Please specify the location and aspect of Decay/Cavity in section of Tree Photos or Comments (e.g. Location of Decay/Cavity with height above ground level and aspect of Decay/Cavity opening) 請 於 樹 木 相 片 或 評 註 部 分 詳 細 說 明 腐 爛 / 樹 洞 的 位 置 及 方 位 例 : 腐 爛 / 樹 洞 離 地 距 離 及 腐 爛 / 樹 洞 開 口 面 向 的 方 向 TARGET (people or property potentially affected by tree/branch failure) 目 標 ( 因 樹 木 / 枝 幹 倒 下 而 致 可 能 受 影 響 的 人 或 財 產 ): Use under tree 在 樹 下 之 用 途 : (multiple answers allowed 可 選 多 於 一 項 ) :) 0 Building 建 築 物 Parking 停 車 位 Traffic 交 通 Recreation 康 樂 Gathering point 聚 集 地 點 Pedestrians 行 人 道 Hardscape 園 藝 景 觀 裝 置 Others 其 他 (please specify 請 說 明 ) : # Can target be moved 能 否 移 除 目 標? Yes 是 No 否 Can use of site be restricted 可 否 限 制 場 地 的 使 用? Yes 是 No 否 Frequency of use of location 使 用 該 地 點 的 頻 密 程 度 : Occasional use 偶 爾 使 用 Intermittent use 間 歇 使 用 Frequent use 經 常 使 用 Constant use 恆 常 使 用 HAZARD RATING 危 害 評 估 : Failure potential 倒 下 的 可 能 性 : Tree or part likely to fall 樹 木 或 枝 條 有 可 能 倒 下 1=low 低 2=medium 中 3=high 高 4=severe 極 高 Trunk 樹 幹 Branch/limb 枝 幹 Whole 整 棵 Size of part Failure Potential + Size of Part + Target Rating = Hazard Rating 倒 塌 可 能 + 部 位 大 小 + 目 標 評 估 = 危 害 評 估 1 + 3 + 1 = 5 部 位 大 小 : 1= < 150mm 2= 150-450mm 3= 451-750mm 4= > 750mm Target rating 目 標 評 估 : 1 occasional use 偶 爾 使 用 2 intermittent use 間 歇 使 用 3 frequent use 經 常 使 用 4 constant use 恆 常 使 用

REMEDIAL/RISK MITIGATION MEASURES Ctf TRUE Ctf TRUE 風 險 緩 減 措 施 (can tick more than one 可 選 多 於 一 項 )* : Anti vs Actu #VALUE! Actu vs Anti #VALUE! Remedial/Risk Mitigation measures taken. 已 施 行 的 風 險 緩 減 措 施 (please specify 請 說 明 ) : REMEDIAL/RISK MIT Remedial/Risk Mitigation measures proposed to be taken as specified below: 將 會 施 行 以 下 所 指 明 的 風 險 緩 減 措 施 : Pruning 修 剪 : Remove defective parts Crown cleaning FALSE Date of Completion for 移 去 有 缺 陷 部 份 清 理 樹 冠 Date: Crown thinning 疏 減 樹 冠 Remove stub 移 去 殘 端 部 份 Crown raising 提 升 樹 冠 Crown reduction 縮 減 樹 冠 Tree Removal 移 除 樹 木 : # Cabling/Bracing/Propping 安 裝 纜 索 或 支 撐 物 : Move Target 移 走 目 標 : Restrict use within fall zone 限 制 可 能 發 生 樹 木 倒 下 或 枝 條 斷 裂 的 範 圍 使 用 Pest/ disease control 控 制 病 蟲 害 : Needs further inspection within months 需 於 個 月 內 再 次 檢 查 樹 木 (please specify 請 說 明 ): Month TRUE Date: Date: Date: Date: Date: Anticipated Date of Completion 預 計 完 成 日 期 (dd/mm/yyyy) Date of Completion 完 成 日 期 (dd/mm/yyyy) Duplicate boxes for Res Comments 評 註 : ### ### ## ## Attached Information 附 夾 資 料 (Maximum 20 attachments and total 40MB allowed 最 多 可 容 納 20 個 附 件 並 合 計 不 多 於 40MB) Attachment: 附 件 (Please double click the yellow area to get the related file 請 雙 擊 黃 色 部 份 並 選 取 相 關 附 件 ) Site Plan 場 地 平 面 圖 (At least 1 Site Plan is provide 最 少 提 供 一 個 場 地 平 面 圖 ) 1 Description 說 明 : Add Site Plan Delete Site Plan Tree Photo 樹 木 相 片 (At least 1 Tree Photo is provide 最 少 提 供 一 個 樹 木 相 片 ) 1 Description 說 明 : Add Tree Photo Delete Tree Photo Resistograph Chart 微 鑽 阻 力 測 試 Add Resistograph Chart Delete Resistograph Chart 1 Description 說 明 : Tomograph 聲 納 圖 像 Add Tomography Delete Tomography 1 Description 說 明 : Other Attachments 其 他 附 件 (Please specific 請 註 明 ) Add Others Delete Others 1 Subject Title 標 題 : Description 說 明 : Note: Please read in conjunction with TMO s Guidelines on Tree Risk Assessment and Management Arrangement and relevant Technical Circulars promulgated on Development Bureau website www.trees.gov.hk 請 參 閱 發 展 局 網 頁 www.trees.gov.hk 樹 木 管 理 辦 事 處 的 樹 木 風 險 評 估 安 排 及 管 理 指 引 及 相 關 技 術 通 告 DEVB TMIS TRA Form2 (Nov 2015)

Appendix 9 - Explanatory Notes for Form 2 1. General Information The Inspection Officer shall make reference to the previous tree inspection records, if available, to help to identify changes in the site conditions and tree conditions. 1.1 Inspection Officer and Endorsement Officer For outsourced tree inspection works, the consultant / contractor staff can serve as the Inspection Officer to conduct the inspection. The Endorsement Officer is the supervisory / managerial staff at a rank higher than that of the Inspection Officer who oversees the Tree Risk Assessment process. For outsourced tree inspection works, the supervisory / managerial staff of the consultant/contractor firm can serve as Endorsement Officer. Inspection Officer and Endorsement Officer for Form 2 need to meet the requirements on academic / professional qualification and / or training, and work experience as listed in Appendix 7. 2. Location Information Please refer to the Explanatory Notes for Form 1 in Appendix 5. 3. No. and DBH of Trunk The tree with multiple trunks should have each trunk numbered in sequence (i.e. #1, #2 etc.) and the photographic records should include such numbers. The DBH should be measured at 1.3 m above the ground. For measurement of trees with multiple trunks, please refer to AFCD s Nature Conservation Practice Note No. 02 (Rev. Jun 2006) Measurement of Diameter at Breast Height (DBH) (http://www.afcd.gov.hk/english/conservation/con_tech/con_tech.html). 4. Tree height The estimated height of the tree above ground to the top of the tree crown. For accurate measurement, making use of a clinometer / range pole is recommended. 5. Tree spread The estimated width of the tree crown. For asymmetric tree crown, the longest axis, should be measured. Greening, Landscape and Tree Management Section A9-1

6. Age class A broad indication of the tree age class would suffice. 7. General condition, Crown condition, Branch condition, Trunk condition and Root condition Refer to Pictorial Guide for Tree Maintenance to Reduce Tree Risks (http://www.trees.gov.hk/filemanager/content/attachments/pictorialguidefortree MaintenanceToReduceTreeRisk(eng).pdf) for reference on tree defects. Thorough inspection on the root collar condition is important to ensure that structural defects adversely affecting anchorage of the trees can be identified as early as possible for adoption of proper mitigation measures. Root collar inspection should include sounding test and examination of the soil and root conditions using proper hand tools. The findings, analysis and recommendations should be elaborated in the comments with adequate photos to illustrate the condition of root collar. Pests and diseases which can lead to severe health and structural problems, such as BRR Disease and decay caused by Ganoderma spp. and termites, should be identified with adequate photos, if any. Further detailed examination and analysis by advanced equipment, such as tomography or resistography, should be conducted as appropriate to ascertain the condition of the trees, particularly for OVTs and large mature trees in which particular concern is required for their preservation. 8. Site condition Restricted root growth area inside dripline The Inspection Officer should tick the most appropriate box to reflect the site condition. 9. Target Please refer to the Explanatory Notes for Form 1 in Appendix 5. Use under tree The Inspection Officer should tick the relevant use of areas under the tree. Please specify in the Others column as appropriate. Greening, Landscape and Tree Management Section A9-2

10. Hazard rating In tree risk assessment, a potential hazard exists if tree part(s) is / are identified as a likely source of harm. The hazard rating helps to conclude the overall risk level and decide on the appropriate follow-up action so as to reduce the risk posed to public safety. The focus is on identifying and prioritising appropriate hazard abatement measures for high-scoring trees. The hazard rating consists of three components:- Failure Potential Size of Part Target Rating This relates to the likelihood of failure of a defective tree or branch. This relates to the diameter of a defective part which would affect the consequence of failure. This relates to use of the target area which would affect the likelihood of impacting a target by the concerned defective tree part. Generally speaking, trees with a total score of 9 to 12 in the hazard rating as evaluated using TRA Form 2 warrant special attention. 11. Remedial / Risk Mitigation Measures To recommend remedial / risk mitigation measures to reduce the potential tree risk. To provide a record of continuous tree monitoring / management efforts. The removal of defective parts of the tree, installation of support system, pest and disease control should be undertaken in a timely manner. It is necessary to mitigate the tree risk promptly to protect public safety. Records and photos on mitigation measures should be provided. The date of completion of the risk mitigation measures should be recorded as appropriate. Greening, Landscape and Tree Management Section A9-3

12. Comments Categorisation of the TRIAGE system (if any) and additional information on trees which require further attention should be recorded to facilitate identification of appropriate follow-up action and future monitoring. Provide a critical review and analysis of the collected information Provide comparison with previous records and a comprehensive recommendation, if required, based on the systematic observation as detailed in the Form 2. Confirm the major structural defects or health problems have been mitigated after the completion of mitigation measures in the Form 2 for downgrading a TRIAGE tree from Red category to Yellow category. Record the recommendation for downgrading a TRIAGE tree to Yellow category. 13. Attached Information 13.1 Site Plan and Tree Photo Tree location and photo(s) should be attached to Form 2 in every case. For photographic record, please refer to Photo-taking Guidelines for Tree Risk Assessment in Appendix 6 for the detailed requirements. 13.2 Resistograph Chart and Tomograph If a tree inspection by resistography or sonic tomography is conducted, attach the inspection record as supplementary information. Greening, Landscape and Tree Management Section A9-4

13.3 Others Other observations requiring follow up actions such as overgrown ground vegetation near root flare / trunk base requiring clearance by the management department or agent to facilitate root collar inspection have to be explicitly recorded. Location Plan Photo no. 1 Highly restricted growing conditions Photo no. 2 Overview Photo no. 3 Wounds on branches Greening, Landscape and Tree Management Section A9-5