Table 1. Stonewall tree assessment results of T1. Table 1-p. 1 A: … · 2015. 11. 10. · Bleeding or sap flow N Defect type: Galls N 1. Canker ⃝ Girdling wire/rope N 2. Decay

Table 1. Stonewall tree assessment results of T1. Table 1-p. 1

A: WALL TREE SURVEY 2011

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SITE & DIMENSIONS

Basic information: Height attribute (m):

Tree reference no. Wall height 5.23 1

Tree register no. Trunk base elevation 5.23 2

Species First branch height 1.46 3

Species (Chinese) Tree height 7.26 4

Tree age class

OVT code Crown radius (m):

Map ref Crown radius // left 4.44 1

Survey date Crown radius // right 3.78 1

Assessor Crown radius ┴ front 6.04 2

Last inspection date Crown radius ┴ back 3.11 2

Wall or slope ID: Trunk DBH (cm):

SIMAR slope # Trunk A 30 3

Slope ID Trunk B

Trunk C

Location information: Trunk D

Street Trunk E

Location 1 Trunk F

Location 2 Sum 30

Nearby utility post Aggregate 30

Tree lean (deg) 15

Adjacent landuse:

Landuse at toe Wall condition at trunk base:

Landuse at crest Masonry block Intact Cracked Shifted 4

Development density

Root spread on wall:

Adjacent building at crest: Lateral spread (m) 3.35 4

Building storey Vertical spread (m) 5.23 4

Construction activities

Environment:

Solar access

Air quality

Wind exposure

Landuse: 1. Residential 2. Government institutional community 3. Commercial 4. Open space 5. Slope 6. Other

Crown radius: left and right are reckoned with the assessor facing the wall.

Trunk DBH: Reckoned one by one from right to left in a clockwise direction with the assessor facing the wall.

T001

Ficus microcarpa

細葉榕

Young Mature Senescent

Y

C.Y. Jim

D M Y

11SW-A/R577

11SW-A/R577

NA

6/Jun/2012

Bonham Road

St Stphen's Lane

31759

Low Medium High

Low Medium High

Low Medium High

1 2 3 4 5 6

1 2 3 4 5 6

Low Medium High

30

N Y

Table 1-p. 2

B: WALL TREE SURVEY 2011

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ROOTS

WALL SURFACE ROOTS Biotic invasion symptoms:

Spreading geometry: Termite mud tube N

1. No spread (

Table 1-p. 3

C: WALL TREE SURVEY 2011

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CROWN & MAIN SCAFFOLD

CROWN

Live crown size: Twig dieback:

1. Low 50% ⃝

Asymmetric crown N 2 Abnormal growth:

Topped crown N 2 Water sprouts 0

Tipped crown N 2 Epicormic branch 0

Excessive reduction: Pest & disease:

Excessively thinned crown N 2 Leaf consumption 0

Excessive lower branch loss N 2 Other symptom 0

Neighbour tree: Tree vigour:

Number of neighbours 0 1 1. Good ❶ 2

Crown interlocking 0 1 2. Average ⃝

Stem grafting 0 1 3. Poor ⃝

Growth restriction:

1. Building: wall side N 1 MAIN SCAFFOLD

2. Building: opposite side N 1 Stem co-dominance:

3. Fence N 1. Single stem ❶ 1

4. Other N 2. Multipe stems: one dominant ⃝

Foliage density: 3. Two co-dominant ⃝

1. Normal ❶ 2 4. Over two co-dominant ⃝

2. Sparse ⃝ Trunk base position:

Leaf size: 1. Wall crest ❶ 1

1. Normal ❶ 2 2. Wall face ⃝

2. Small ⃝ 3. Wall toe ⃝

Leaf colour: Other defects:

1. Normal ❶ 2 Gap in crown N

2. Chorotic ⃝ Suspended deadwood N

3. Brown (>5% wilting) ⃝ Vascular epiphytic/parasitic growth:

Abundance 0

Type NA

⃝ Mark the most appropriate multiple choice box as ❶❷❸❹❺.

Ordinal ranking: 0. Nil or insignificant 1. Little or low 2. Some or medium 3. Profuse or severe

Table 1-p. 4

D: WALL TREE SURVEY 2011

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TRUNK

NOTABLE DEFECTS CRITICAL DEFECTS

Trunk curvature: Trunk code 0

Curved trunk with code 0 Defect type:

Meandering trunk with code 0 1. Canker ⃝

Trunk base & taper: 2. Decay without fruiting body ⃝

Inadequate taper 0 3. Decay with fruiting body ⃝

Limited tension wood 0 4. Cavity ⃝

Basal detachment from wall 0 Position & dimension:

Bark symptoms: Position (basal, middle, terminal) 0

Increment strip N Length (10 cm) 0

Loosened or detached N Width (10 cm) 0

Kinked or buckled N Depth (10 cm) 0

Darkened N Response wood:

Wet N Woundwood formation N

Other surficial symptoms: Bulge wood formation N

Wound with decay N

Lightning scar N Trunk code 0

Bleeding or sap flow N Defect type:

Galls N 1. Canker ⃝

Girdling wire/rope N 2. Decay without fruiting body ⃝

Penetrative symptoms: 3. Decay with fruiting body ⃝

Crack: longitudinal N 4. Cavity ⃝

Crack: transverse N Position & dimension:

Seam N Position (basal, middle, terminal) 0

Pointed rib N Length (10 cm) 0

Bulge N Width (10 cm) 0

Depression/buckle N Depth (10 cm) 0

Biotic invasion symptoms: Response wood:

Termite mud tube N Woundwood formation N

Termite burrowed wood N Bulge wood formation N

Borer ingress or exit holes N



Trunk code (A, B, C, D, E or F): The code assigned to each trunk in Part A of the form should be chosen.

Defect position (three stem segments): 1. First (basal) 1/3 2. Second (middle) 1/3 3. Third (terminal) 1/3

Length, width and depth of defect: 1. 10 cm

Table 1-p. 5

E: WALL TREE SURVEY 2011

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CROTCH (mainly defective first

order)

Trunk code of crotch 0 Trunk code of crotch 0

Defect type: Defect type:

V-crotch incipient state N V-crotch incipient state N

V-crotch with included bark N V-crotch with included bark N

V-crotch with ear N V-crotch with ear N

V-crotch with decay N V-crotch with decay N

V-crotch with cavity N V-crotch with cavity N

V-crotch with split stem N V-crotch with split stem N

Related symptoms: Related symptoms:

Crotch with sap flow N Crotch with sap flow N

Crotch with darkened bark N Crotch with darkened bark N

Bark crease underneath N Bark crease underneath N

Debris accumulation N Debris accumulation N

Water pocket N Water pocket N

Other N Other N















Other N Other N


Table 1-p. 6

F: WALL TREE SURVEY 2011

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LIMB & MAIN BRANCH

(defective)

NOTABLE DEFECTS

Stub: Bulge N

With woundwood N Depression/buckle N

Little or no woundwood N Biotic invasion symptoms:

Jagged end or torn bark N Termite mud tube N

Excessive reduction or decline: Termite burrowed wood N

Topped/tipped N Borer ingress or exit holes N

Broken or hanger N

Dead branch N CRITICAL DEFECTS

Abnormal posture: Defect 0

Bowed downwards N Defect type:

Curved upwards N 1. Canker ⃝

Meandering or kinked N 2. Decay without fruiting body ⃝

Elbow joint N 3. Decay with fruiting body ⃝

Opposite N 4. Cavity ⃝

Crowded (>2) Y 7 Position & dimension:

Closely spaced N Position (basal, middle, terminal) 0

Crossed N Length (10 cm) 0

Excessive loading: Width (10 cm) 0

Too long N Depth (10 cm) 0

Too low N Response wood:

Too thick (heavy) N Woundwood formation N

Excessive end load N Bulge wood formation N

Bark symptoms:

Increment strip N Defect 0

Loosened or detached N Defect type:

Kinked or buckled N 1. Canker ⃝

Darkened N 2. Decay without fruiting body ⃝

Wet N 3. Decay with fruiting body ⃝

Other surficial symptoms: 4. Cavity ⃝

Wound with decay N Position & dimension:

Lightning scar N Position (basal, middle, terminal) 0

Bleeding or sap flow N Length (10 cm) 0

Galls N Width (10 cm) 0

Girdling wire/rope N Depth (10 cm) 0

Penetrative symptoms: Response wood:

Crack: longitudinal shear N Woundwood formation N

Crack: transverse N Bulge wood formation N

Seam N

Pointed rib N



Limb of main branch: include only stems with a diameter >10 cm.

Defect position (three stem segments): 1. First (basal) 1/3 2. Second (middle) 1/3 3. Last (terminal) 1/3

Circumference affected by defect: 1. 40%

Table 1-p. 7

G: WALL TREE SURVEY 2011

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HAZARD ASSESSMENT

SITE AND TREE OVERVIEW HAZARD RATING SCORE

Fall zone target: Probability of failure (A 1-4):

1. Pedestrians Y 1 1. Low ❶

2. People gathering spot N 2. Moderate ⃝

3. Open space recreation N 3. High ⃝

4. Vehicle parking N 4. Extremely high ⃝

5. Vehicular traffic Y 1 Size of defective part (B 1-4):

Target management: 1. 750 mm diameter ⃝

Tree part likely to fall: Frequency of use (C 1-4):

1. Whole tree ⃝ 1. Occasional ⃝

2. Trunk/limb ⃝ 2. Intermittent ⃝

3. Branch ❸ 1 3. Frequent ❸

Key risk factor assessment: 4. Constant ⃝

Root problems N Risk score (3-12):

Canker N Risk score=A+B+C 5

Decay/cavity N Risk rating:

Crack N 1. Very low (score=3) ⃝

Weak branch union N 2. Low (score=4-6) ❷

Poor tree architecture Y 7 3. Medium (score=7-9) ⃝

Dead wood N 4. High (score=10-12) ⃝

Wind exposure: Additional risk factor (D 0-2):

1. Single tree ❶ 1 Factor 1 0

2. Emergent tree ⃝ Factor 2 0

3. Tree group: edge ⃝

4. Tree group: not edge ⃝

5. Recently exposed tree ⃝


Risk score: Sum the scores of A, B and C and insert the result.

Additiona risk factor: Insert a brief description of the additional risk factor.

Table 1-p. 8

H: WALL TREE SURVEY 2011

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RECOMMENDATIONS

DIAGNOSIS & TREATMENT 6. Remove hanger 0

A. Internal decay/shell investigation: 7. Trim selected wounds 0

1. Microdrilling 0 H. Supplementary support:

2. Sonic tomograph 0 1. Cable bracing 0

3. Close visual & mallet inspection 0 2. Rod bracing 0

B. Pest-disease diagnosis/treatment: 3. Propping 0

1. Exterminate termite 0 I. Protection against construction:

2. Identify pest or pathogen 0 1. Establish tree protection zone 0

3. Apply control and treatment 0 2. Establish soil protection zone 0

CORRECTIVE-PREVENTIVE PRUNING 3. Evaluate groundwater impact 0

C. Pruning-reduction: 4. Prevent incursion 0

1. Reduce crown height 0 5. Support wall 0

2. Reduce crown spread 0 6. Support tree 0

3. Reduce crown weight 0 7. Preventive tree treatment 0

4. Balance the crown 0 8. Institute monitoring 0

D. Pruning-trimming J. Remove tree:

1. Trim broken branch 0 1. Establish justifications 0

2. Thin the crown 0 2. Prepare felling application 0

3. Trim crossed/competing branch 1 7 K. Other recommended actions:

4. Trim defective branch 0 1. OVT nomination 0

5. Trim branch end weight 0 2. Install information plaque 0

E. Pruning-removal 3. Inspection frequency (months) 12

1. Remove dead branch 0 4. Inspect after severe storm Y

2. Remove hazardous branch 0 HABITAT MANAGEMENT

3. Remove stubs 0 L. Ameliorate growth limitations:

4. Remove selected epicormics 0 1. Ameliorate stem limitations 1 7

5. Remove selected sprouts 0 2. Ameliorate root limitations 1 8

6. Remove dead surface roots 0 3. Manage aerial roots 0

F. Pruning-maintain clearance M. Wall treatment:

1. Footpath 0 1. Remove joint seals 0

2. Carriageway 0 2. Remove obsolete installations 0

3. Adjacent building 0 3. Remove weep hole rubbish 0

4. Opposite building 0 4. Repair leaking pipes 0

TREE MANAGEMENT N. Soil treatment:

G. Tree cleaning: 1. Install soil strip at toe 0

1. Remove surface root rubbish 0 2. Install soil strip at crest 1 8

2. Removing girdling wire/rope 0 3. Widen soil strip at toe 0

3. Remove embedded objects 0 4. Widen soil strip at crest 0

4. Remove crotch debris 0 5. Improve soil at toe 0

5. Remove hanging rubbish 0 6. Improve soil at crest 0

Urgency rating: 0. Nil 1. Low 2. Medium 3. High ? Depends on results of detailed inspection

Table 1-p. 9

I: WALL TREE SURVEY 2011

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EXPLANATIONS OF

RECOMMENDATIONS

7

7

8

8

D3. Trim crossed/competing branch: Remove one of the two rather upright and closely-spaced

competing branches.

L1. Ameliorate stem limitations: Remove ropes and fabric wrapping around the limbs.

L2. Ameliorate root limitations: Replace parapet wall with railing to permit root growth into soil at

the wall crest.

N2. Install soil strip at crest: install a narrow soil strip at wall crest to permit root growth and to

strengthen tree anchorage.

Table 2. Stonewall tree assessment results of T2. Table 2‐p. 1


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SITE & DIMENSIONSBasic information: Height attribute (m):Tree reference no. Wall height 3.84 1Tree register no. Trunk base elevation 3.84 1Species First branch height 1.67 1Species (Chinese) Tree height 16.68 1Tree age classOVT code Crown radius (m):Map ref Crown radius // left 12.79 1Survey date Crown radius // right 14.61 1Assessor Crown radius ┴ front 15.21 4,5Last inspection date Crown radius ┴ back 8.30 4,5

Wall or slope ID: Trunk DBH (cm):SIMAR slope # Trunk A 115 8,9Slope ID Trunk B 51 8,9

Trunk C 74 8,9Location information: Trunk DStreet Trunk ELocation 1 Trunk FLocation 2 Sum 240Nearby utility post Aggregate 146

Tree lean (deg) Base 32, A1 13, A2 ‐12, B 19, C 9Adjacent landuse:Landuse at toe Wall condition at trunk base:Landuse at crest Masonry block Intact Cracked Shifted 16,18Development density

Root spread on wall:Adjacent building at crest: Lateral spread (m) 6.60 10Building storey Vertical spread (m) 3.84 10Construction activities

Environment:Solar accessAir qualityWind exposure

Landuse: 1. Residential 2. Government institutional community 3. Commercial 4. Open space 5. Slope 6. OtherCrown radius: left and right are reckoned with the assessor facing the wall.


Low Medium High Low Medium High

Low Medium High

1 2 3 4 5 6 1 2 3 4 5 6 Low Medium High

30 N Y

Bonham RoadSt Stepen's Lane

31758

Y

C.Y.JimD M Y

11SW‐A/R577

11SW‐A/R577

LCSD CW/14

6/Jun/2012

T002

Ficus microcarpa細葉榕


Table 2‐p. 2

B: WALL TREE SURVEY 2011 Rating

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ROOTSWALL SURFACE ROOTS Biotic invasion symptoms:Spreading geometry: Termite mud tube N1. No spread (

Table 2‐p. 3

C: WALL TREE SURVEY 2011 Rating

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CROWN & MAIN SCAFFOLDCROWNLive crown size: Twig dieback:1. Low 50% ⃝Asymmetric crown N Abnormal growth:Topped crown N Water sprouts 0 32,37,45,49Tipped crown Y 30 Epicormic branch 2 30,35,38,41,47,48Excessive reduction: Pest & disease:Excessively thinned crown N Leaf consumption 0Excessive lower branch loss Y 1,4 Other symptom 0Neighbour tree: Tree vigour:Number of neighbours 2 2,5 1. Good ❶ 20Crown interlocking 0 2. Average ⃝Stem grafting 0 3. Poor ⃝Growth restriction:1. Building: wall side Y 46,50 MAIN SCAFFOLD2. Building: opposite side Y 27,28 Stem co‐dominance:3. Fence N 1. Single stem ⃝4. Other N 2. Multipe stems: one dominant ⃝Foliage density: 3. Two co‐dominant ⃝1. Normal ❶ 21 4. Over two co‐dominant ❹ 8,92. Sparse ⃝ Trunk base position:Leaf size: 1. Wall crest ❶ 101. Normal ❶ 21 2. Wall face ⃝2. Small ⃝ 3. Wall toe ⃝Leaf colour: Other defects:1. Normal ❶ 21 Gap in crown N2. Chorotic ⃝ Suspended deadwood N3. Brown (>5% wilting) ⃝ Vascular epiphytic/parasitic growth:

Abundance 0Type NA

⃝ Mark the most appropriate mul ple choice box as ❶❷❸❹❺.


Table 2‐p. 4

D: WALL TREE SURVEY 2011 Rating

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TRUNKNOTABLE DEFECTS CRITICAL DEFECTSTrunk curvature: Trunk code A1Curved trunk with code 0 Defect type:Meandering trunk with code 0 1. Canker ⃝Trunk base & taper: 2. Decay without fruiting body ❷ 31Inadequate taper 0 3. Decay with fruiting body ⃝Limited tension wood 0 4. Cavity ⃝Basal detachment from wall 0 Position & dimension:Bark symptoms: Position (basal, middle, terminal) 2 31Increment strip N Length (10 cm) 3 31Loosened or detached N Width (10 cm) 3 31Kinked or buckled N Depth (10 cm) 2 31Darkened N Response wood:Wet N Woundwood formation NOther surficial symptoms: Bulge wood formation Y 31

Wound with decay Y 31,36,55‐59Lightning scar N Trunk code A1Bleeding or sap flow N Defect type:Galls N 1. Canker ⃝Girdling wire/rope N 2. Decay without fruiting body ❷ 32Penetrative symptoms: 3. Decay with fruiting body ⃝Crack: longitudinal N 4. Cavity ⃝Crack: transverse N Position & dimension:Seam Y 55 Position (basal, middle, terminal) 2 32Pointed rib N Length (10 cm) 3 32Bulge Y 31,5‐57 Width (10 cm) 2 32Depression/buckle Y 57 Depth (10 cm) 2 32Biotic invasion symptoms: Response wood:Termite mud tube N Woundwood formation NTermite burrowed wood Y? 32 Bulge wood formation NBorer ingress or exit holes N




Defect position (three stem segments): 1. First (basal) 1/3 2. Second (middle) 1/3 3. Third (terminal) 1/3Length, width and depth of defect: 1. 10 cm

Table 2‐p. 5


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TRUNKNOTABLE DEFECTS CRITICAL DEFECTSTrunk curvature: Trunk code BCurved trunk with code 0 Defect type:Meandering trunk with code 0 1. Canker ⃝Trunk base & taper: 2. Decay without fruiting body ❷ 57Inadequate taper 0 3. Decay with fruiting body ⃝Limited tension wood 0 4. Cavity ⃝Basal detachment from wall 0 Position & dimension:Bark symptoms: Position (basal, middle, terminal) 2 57Increment strip N Length (10 cm) 3 57Loosened or detached N Width (10 cm) 3 57Kinked or buckled N Depth (10 cm) 2 57Darkened N Response wood:Wet N Woundwood formation NOther surficial symptoms: Bulge wood formation Y 57Wound with decay NLightning scar N Trunk code BBleeding or sap flow N Defect type:Galls N 1. Canker ⃝Girdling wire/rope N 2. Decay without fruiting body ❷ 56Penetrative symptoms: 3. Decay with fruiting body ⃝Crack: longitudinal N 4. Cavity ⃝Crack: transverse N Position & dimension:Seam N Position (basal, middle, terminal) 2 56Pointed rib N Length (10 cm) 3 56Bulge N Width (10 cm) 3 56Depression/buckle N Depth (10 cm) 2 56Biotic invasion symptoms: Response wood:Termite mud tube N Woundwood formation NTermite burrowed wood N Bulge wood formation Y 56Borer ingress or exit holes N





Table 2‐p. 6

E: WALL TREE SURVEY 2011 Rating

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CROTCH (mainly defective first order)Trunk code of crotch 0 Trunk code of crotch 0Defect type: Defect type:V‐crotch incipient state N V‐crotch incipient state N V‐crotch with included bark N V‐crotch with included bark N V‐crotch with ear N V‐crotch with ear N V‐crotch with decay N V‐crotch with decay N V‐crotch with cavity N V‐crotch with cavity N V‐crotch with split stem N V‐crotch with split stem N Related symptoms: Related symptoms:Crotch with sap flow N Crotch with sap flow N Crotch with darkened bark N Crotch with darkened bark N Bark crease underneath N Bark crease underneath N Debris accumulation N Debris accumulation N Water pocket N Water pocket N Other N Other N

Trunk code of crotch 0 Trunk code of crotch 0Defect type: Defect type:V‐crotch incipient state N V‐crotch incipient state N V‐crotch with included bark N V‐crotch with included bark N V‐crotch with ear N V‐crotch with ear N V‐crotch with decay N V‐crotch with decay N V‐crotch with cavity N V‐crotch with cavity N V‐crotch with split stem N V‐crotch with split stem N Related symptoms: Related symptoms:Crotch with sap flow N Crotch with sap flow N Crotch with darkened bark N Crotch with darkened bark N Bark crease underneath N Bark crease underneath N Debris accumulation N Debris accumulation N Water pocket N Water pocket N Other N Other N


Table 2‐p. 7

F: WALL TREE SURVEY 2011 Rating

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LIMB & MAIN BRANCH (defective)NOTABLE DEFECTSStub: Bulge Y 52,61,62With woundwood N Depression/buckle Y 52Little or no woundwood Y 36,51,63 Biotic invasion symptoms:Jagged end or torn bark Y 37 Termite mud tube NExcessive reduction or decline: Termite burrowed wood NTopped/tipped Y Borer ingress or exit holes N

Broken or hanger N CRITICAL DEFECTSDead branch Y 43,64 Defect 1Abnormal posture: Defect type:Bowed downwards N 1. Canker ⃝Curved upwards Y 35 2. Decay without fruiting body ❷ 53Meandering or kinked Y 34,40 3. Decay with fruiting body ⃝Elbow joint Y 41 4. Cavity ⃝Opposite N Position & dimension:Crowded (>2) Y 39 Position (basal, middle, terminal) 2 53Closely spaced N Length (10 cm) 3 53Crossed N Width (10 cm) 2 53Excessive loading: Depth (10 cm) 2 53Too long N Response wood:Too low N Woundwood formation NToo thick (heavy) N Bulge wood formation NExcessive end load Y 43,45,49Bark symptoms: Defect 2Increment strip N Defect type:Loosened or detached N 1. Canker ⃝Kinked or buckled N 2. Decay without fruiting body ❷ 61Darkened N 3. Decay with fruiting body ⃝Wet N 4. Cavity ⃝Other surficial symptoms: Position & dimension:

Wound with decay Y Position (basal, middle, terminal) 2 61

Lightning scar N Length (10 cm) 3 61Bleeding or sap flow N Width (10 cm) 2 61Galls N Depth (10 cm) 2 61Girdling wire/rope N Response wood:Penetrative symptoms: Woundwood formation NCrack: longitudinal shear Y 65 Bulge wood formation Y 61Crack: transverse NSeam NPointed rib N



Limb of main branch: include only stems with a diameter >10 cm.Defect position (three stem segments): 1. First (basal) 1/3 2. Second (middle) 1/3 3. Last (terminal) 1/3Circumference affected by defect: 1. 40%

30,32,37,41,44,47‐49,63

37,38,42,51‐53, 61,64

Table 2‐p. 8

G: WALL TREE SURVEY 2011 Rating

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HAZARD ASSESSMENT SITE AND TREE OVERVIEW HAZARD RATING SCOREFall zone target: Probability of failure (A 1‐4):1. Pedestrians Y 2,3 1. Low ❶2. People gathering spot N 2. Moderate ⃝3. Open space recreation N 3. High ⃝4. Vehicle parking N 4. Extremely high ⃝5. Vehicular traffic Y 2,3 Size of defective part (B 1‐4):Target management: 1. 750 mm diameter ⃝Tree part likely to fall: Frequency of use (C 1‐4):1. Whole tree ⃝ 1. Occasional ⃝2. Trunk/limb ⃝ 2. Intermittent ⃝3. Branch ❸ 3. Frequent ❸Key risk factor assessment: 4. Constant ⃝Root problems N Risk score (3‐12):Canker N Risk score=A+B+C 5Decay/cavity Y Risk rating:Crack N 1. Very low (score=3) ⃝Weak branch union N 2. Low (score=4‐6) ❷Poor tree architecture N 3. Medium (score=7‐9) ⃝Dead wood N 4. High (score=10‐12) ⃝Wind exposure: Additional risk factor (D 0‐2):1. Single tree ⃝ Factor 1 Trunk A1 large decayed wound 1 31,55‐572. Emergent tree ⃝ Factor 2 Trunk A1 termite attack? 1 323. Tree group: edge ❸ 4,54. Tree group: not edge ⃝5. Recently exposed tree ⃝


Risk score: Sum the scores of A, B and C and insert the result.Additiona risk factor: Insert a brief description of the additional risk factor.

Table 2‐p. 9


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RECOMMENDATIONSDIAGNOSIS & TREATMENT 6. Remove hanger 0A. Internal decay/shell investigation: 7. Trim selected wounds 2 32,36,38,56,611. Microdrilling 3 31,53,55‐57,61 H. Supplementary support:2. Sonic tomograph 0 1. Cable bracing 0

3. Close visual & mallet inspection 3 33,34,37,38,40,42,52,62,65 2. Rod bracing 0

B. Pest‐disease diagnosis/treatment: 3. Propping 01. Exterminate termite 3? 33 I. Protection against construction:2. Identify pest or pathogen 0 1. Establish tree protection zone 03. Apply control and treatment 0 2. Establish soil protection zone 0CORRECTIVE‐PREVENTIVE PRUNING 3. Evaluate groundwater impact 0C. Pruning‐reduction: 4. Prevent incursion 01. Reduce crown height 0 5. Support wall 02. Reduce crown spread 0 6. Support tree 03. Reduce crown weight 3? 31,55,56 7. Preventive tree treatment 04. Balance the crown 0 8. Institute monitoring 0D. Pruning‐trimming J. Remove tree:1. Trim broken branch 0 1. Establish justifications 02. Thin the crown 0 2. Prepare felling application 03. Trim crossed/competing branch 1 39 K. Other recommended actions:4. Trim defective branch 2? 40‐42, 48,52,53, 55‐57,61,62,65 1. OVT nomination Y 1,4

5. Trim branch end weight 2? 32,34,37, 38,61 2. Install information plaque Y 1,4E. Pruning‐removal 3. Inspection frequency (months) 121. Remove dead branch 2 43,44,64 4. Inspect after severe storm Y2. Remove hazardous branch 0 HABITAT MANAGEMENT3. Remove stubs 2 51,62,63 L. Ameliorate growth limitations:4. Remove selected epicormics 0 1. Ameliorate stem limitations 05. Remove selected sprouts 1 45,49 2. Ameliorate root limitations 1 10,17,196. Remove dead surface roots 0 3. Manage aerial roots 0F. Pruning‐maintain clearance M. Wall treatment:1. Footpath 0 1. Remove joint seals 1 10,17,192. Carriageway 0 2. Remove obsolete installations 03. Adjacent building 1 46,47,50 3. Remove weep hole rubbish 04. Opposite building 1 27,28 4. Repair leaking pipes 0TREE MANAGEMENT N. Soil treatment:G. Tree cleaning: 1. Install soil strip at toe 1 111. Remove surface root rubbish 0 14 2. Install soil strip at crest 1 52. Removing girdling wire/rope 0 3. Widen soil strip at toe 03. Remove embedded objects 1 60 4. Widen soil strip at crest 04. Remove crotch debris 0 5. Improve soil at toe 05. Remove hanging rubbish 1 35 6. Improve soil at crest 0


Table 2‐p. 10

I: WALL TREE SURVEY 2011 Photo

ref.

EXPLANATIONS OF RECOMMENDATIONS

31,53,55‐57, 61

34

37,38,41,42,48,52, 54,58,62

65

32

31,55,56

39

40

A1. Microdrilling: Microdrilling should be conducted by the tree‐maintenance contractor at the recommended positions and orientations as shown in the photograph annotations (pink arrows) to ascertain the extent and magnitude of internal decay vis‐a‐vis the amount and location of the remaining sound wood.

A3. Close visual & mallet inspection: The effect of the decay at the wound on wood strength should be evaluated visually and with the help of a wooden mallet to ascertain the ability of the branch to support the load of its branches and foliage.

C3. Reduce crown weight: If the microdrilling recommended under A1 finds that the decay at the wound has spread to occupy more than one‐third of the nominal trunk diameter, the branch loads of the affected stems have to be reduced correspondingly. The overall interpretation of microdrilling results of stem A1 at and proximal to the large decayed wound (Photo T2‐31) is that there is sufficient sound wood including response wood to support the stem weight. No drastic pruning or stem removal is necessary. As a precautionary measure, about 10% of the end load should be trimmed. The pruning should selectively remove the thinner and weaker branches with a view to leaving an even spread of remaining branches. The decay may continue to deteriorate to a more advanced stage and may spread to affect more wood. This position of weakness needs to be monitored continually in future inspections. For the Stem B defect as shown in Photos T2‐55 and T2‐56, no notable pocket of advanced decay, cavity or crack has been detected along the drill path. The decay at the open wound has not penetrated into the interior of the stem. The results do not call for drastic pruning or end‐load reduction treatment.

A3. Close visual & mallet inspection: This crooked section of the stem A1 branch should be inspected visually at close quarters and with the help of a wooden mallet to see if it is suffering from mechanical defects such as cracking or splitting.

A3. Close visual & mallet inspection: The extent (length and depth) of the crack should be evaluated visually at close quarters and with a wooden mallet to ascertain the impact on the mechanical strength of the branch to support the load of its branches and foliage.

B1. Pest‐disease diagnosis/treatment: The suspected termite attack at the wound of stem A1 (south side) should be checked to see if it is still active. If so, apply effective termite extermination using the hormone bait method at the earliest opportunity.

D3. Trim crossed/competing branch: The sum of the diameters of the three daughter branches displaying the crowded branching habit is notably larger than the parent branch, imposing a heavy burden on it. The problem could be partly relieved by removing one of the two parallel branches.

D4. Trim defective branch: At the tipped end the long but relatively slender branch, an epicormic branch has emerged with an elbow joint. As such a structure is potentially hazardous, and it carries a limited amount of foliage, the parent together with its daughter is recommended for removal.

41

48

52

55,56.57

42,53,61,62

65

D4. Trim defective branch: If the close inspection recommended under A3 finds that the truncated end of the branch has developed decay and structural defect, the attached epicormic branches should be trimmed to reduce the burden on the parent stem.

D4. Trim defective branch: At the tipped end the branch, an epicormic branch has emerged with an elbow joint. The close evaluation recommended under A3 should inform whether the decayed tip has sufficient sound wood to hold the epicormic branch. If not, the daughter branch should be reduced according to the amount of sound wood at the junction.

D4. Trim defective branch: The open wound has developed decay and cavity, and the resulting loss of mechanical strength has induced response wood formation in the form of bulgewood. The extent of decay should be investigated by at close quarters under recommendations A1 and A3. The load on the defective branch should be reduced in proportion to the amount of remaining sound wood. For Stem C ashown in Photo T2‐61, the drilling results show that a small 4.5 cm diameter cavity has formed to incur a t/r ratio of 0.63 on the thinner side of the residual wood shell. As a precautionary measure, about 10% of the end load should be trimmed. The pruning should selectively remove the thinner and weaker branches with a view to leaving an even spread of remaining branches.

D4. Trim defective branch: The crack at the branch crotch should be assessed at close quarters to find out its length and depth and whether internal decay has developed, as recommended under A3. The result will determine the amount of wood to be removed from the affected branch. In the extreme case, the entire branch should be removed along the dotted line.

D4. Trim defective branch: If the close inspection recommended under A3 finds that the wound has developed advanced decay and structural defect that may compromise its mechanical strength to such an extent that it cannot support its own weight, the relatively long and stout truncated limb should be removed by the proper removal cut at its fork with its parent stem.

D4. Trim defective branch: If the microdrilling recommended under A1 finds that the wound has developed advanced decay and structural defect that may compromise its mechanical strength to such an extent that it cannot support its load, the weight of the branches supported by the stem should be trimmed. The amount to be removed should be contingent upon the condition and quantity of the remaining sound wood. The defect shown in Photos T2‐55 and T2‐56 are not associated with notable pocket of advanced decay, cavity or crack along the drill path. The decay at the open wound has not penetrated into the interior of the stem. The results do not call for drastic pruning or end‐load reduction treatment. The two drillings shown by Photo T2‐57 indicate two small 2 cm diameter internal cavities. The decay at the open wound has penetrated into the interior part of the stem, although the spread at the present stage is limited. There is enough sound wood to support the stem. As a precautionary measure, about 10% of the end load should be trimmed. The pruning should selectively remove the thinner and weaker branches with a view to leaving an even spread of remaining branches. The weak point should be continually monitored to check whether it will further aggravate to a more risky stage.

33,37,38

34

43,44,64

51,63

45,49

46,47,50

27,28

14

60

35

E1. Remove dead branch: Both the small and the relatively large dead branches, beset by advanced decay and dead attached branchlets, should be removed to prevent the spread of wood‐decay fungi to adjacent healthy wood.

D5. Trim branch end weight: If the inspection recommended under A3 finds that the crooked section of the branch is suffering from structural defect, the weight of the branch should be correspondingly reduced.

D5. Trim branch end weight: At the tipped end of branches, sprouts have emerged as replacement branches and compensatory photosynthetic tissues. The detailed inspection recommended under A3 should clarify the condition and extent of decay at the tipped ends of the parent branches. The cluster of sprouts attached to the decayed tips should be reduced in proportion to the amount of remaining sound wood. The loading reduction could be achieved by selective trimming of relatively weak and thin sprouts, leaving an even spacing of stronger sprouts. Where only one or two expanded sprouts are attached to the tipped parent branch, the loading can be reduced by branch shortening using a standard reduction cut back to a notable fork.

E5. Remove selected sprouts: The dense cluster of sprouts developed at the tipped end of the branches should be trimmed by removing the relatively weaker and thinner sprouts and leaving an even spread of stronger branches.

F3. Adjacent building: The branches have extended towards the south above St Stephen's Lane to approach the adjacent buildings. To resolve this conflict, the branches that get too close to windows should be trimmed to provide a horizontal clearance of 2 m. Only the standard reduction cut down to a notable fork should be applied in shortening branches. The heading cut is forbidden. A light‐weight telescopic pruning pole could be used to prune the target proximal branches from the nearest windows of the affected residential flats. This way, the need to block the vehicular traffic to conduct pruning could be avoided.

E3. Remove stubs: The stubs with decay should be removed using the standard removal cut at the fork with the parent stem.

F4. Opposite building: The branches have extended towards the north above Bonham Road to approach the opposite buildings. Branches that get too close to windows should be trimmed to provide a horizontal clearance of 2 m. Only the standard reduction cut down to a notable fork should be applied in shortening branches. The heading cut is forbidden. A light‐weight telescopic pruning pole could be used to prune the target proximal branches from the nearest windows of the residential flats. This way, the need to block the vehicular traffic to conduct pruning could be avoided.

G1. Remove surface root rubbish: The rubbish that has deposited on the surface roots and the trunk bases and crotches, together with the leaf litter, should be regularly removed with the help of a brush to avoid moisture accumulation which could induce decay.

G5. Remove hanging rubbish: The rubbish that hangs on the branches of the tree should be carefully extricated and removed in the course of pruning with the help of a hydraulic platform.

G3. Remove embedded objects: The plastic sheet that has been embedded in the trunk should be pulled out manually, if it is possible to do so. Refrain from using tools or excessive force in the extraction process.

32,36,38,56,59,61

1,4

1,4

10,17,19

10,17,19

11

5N2. Install soil strip at crest: An open soil strip filled with a good‐quality soil mix could be installed at the wall crest to allow growth of roots in the soil below the pavement at St Stephen's Lane. Great care should be taken to avoid damaging the existing roots in the aft‐soil. To preserve the walkable width at the narrow lane and to avoid human‐foot trampling of soil, a metal grille could be placed on the soil surface. The advice of a geotechnical should be sought in the design of this soil strip. If a continuous soil strip is not feasible, an intermitted strip could be adopted instead.

G7. Trim selected wounds: The wounds with jagged edges or an uneven surface should be very carefully trimmed using a sharp arborist manual saw and with the help of a carpenter's chisel. As far as possible, well‐formed callus tissues should be left undisturbed.

K2. Install information plaque: A well‐designed and durable information plaque could be installed at St Stephen's Lane which offers a convenient and safe location to appreciate the magnificent wall tree.

M1. Remove joint seals: The joints between masonry blocks have been sealed recently by cement, thus stopping their penetration by tree roots. The rigid cement seal also restricts expansion of existing roots and may cause injurious girdling as they continue to thicken. Where the roots are physically obstructed, consideration could be given to localized removal of the cement seal to permit some new roots to grow into the joints and existing roots to expand.

N1. Install soil strip at toe: An open soil strip filled with a good‐quality soil mix could be installed at the wall toe at Bonham Road to allow growth of roots in the soil below the pavement. Great care should be taken to avoid damaging the existing roots in the soil lying below the pavement. To preserve the walkable width at the narrow pavement and to avoid human‐foot trampling of soil, a metal grille could be placed on the soil surface. The advice of a geotechnical should be sought in the design of this soil strip. If a continuous soil strip is not feasible, an intermitted strip could be adopted instead.

L2. Ameliorate root limitations: The limitations to root growth due to the lack of open and penetrable joints between masonry blocks, and the lack of accessible soil at the wall toe and crest positions, could be ameliorated to enhance tree growth and performance.

K1. OVT nomination: This wall tree is one of the largest amongst the cohort of significant wall trees in Hong Kong. It is notably endowed with a relatively complete biomass structure and crown, and rather robust health. It has fine qualities that deserve special attention and has been designated under the government's Old and Valuable Tree (OVT) Register. It should be kept in the Register.

Table 3. Stonewall tree assessment results of T3. Table 3-p. 1


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SITE & DIMENSIONS

Basic information: Height attribute (m):

Tree reference no. Wall height 3.27 1,7

Tree register no. Trunk base elevation 3.27 1,7

Species First branch height 3.78 2,3

Species (Chinese) Tree height 14.77 1,2

Tree age class

OVT code Crown radius (m):

Map ref Crown radius // left 7.75 2

Survey date Crown radius // right 7.16 2

Assessor Crown radius ┴ front 9.97 3

Last inspection date Crown radius ┴ back 6.11 3

Wall or slope ID: Trunk DBH (cm):

SIMAR slope # Trunk A 38 5,6

Slope ID Trunk B 56 5,6

Trunk C 74 5,6

Location information: Trunk D

Street Trunk E

Location 1 Trunk F

Location 2 Sum 168

Nearby utility post Aggregate 100

Tree lean (deg) Base 40, Tree 8

Adjacent landuse:

Landuse at toe Wall condition at trunk base:

Landuse at crest Masonry block Intact Cracked Shifted 10

Development density

Root spread on wall:

Adjacent building at crest: Lateral spread (m) 9.89 7

Building storey Vertical spread (m) 3.27 7

Construction activities

Environment:

Solar access

Air quality

Wind exposure

Landuse: 1. Residential 2. Government institutional community 3. Commercial 4. Open space 5. Slope 6. Other

Crown radius: left and right are reckoned with the assessor facing the wall.


Low Medium High

Low Medium High

Low Medium High

1 2 3 4 5 6

1 2 3 4 5 6

Low Medium High

30

N Y

Bonham Road

St Stphen's Lane

31757

11SW-A/R577

11SW-A/R577

T003

Ficus microcarpa

細葉榕


NA

6/Jun/2012

Y

C.Y. Jim

D M Y

Table 3-p. 2

B: WALL TREE SURVEY 2011

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ROOTS

WALL SURFACE ROOTS Biotic invasion symptoms:

Spreading geometry: Termite mud tube N

1. No spread (

Table 3-p. 3

C: WALL TREE SURVEY 2011

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CROWN & MAIN SCAFFOLD

CROWN

Live crown size: Twig dieback:

1. Low 50% ⃝

Asymmetric crown Y 3,4 Abnormal growth:

Topped crown N Water sprouts 1 14,16

Tipped crown Y 5,15,17 Epicormic branch 2 16-18

Excessive reduction: Pest & disease:

Excessively thinned crown N Leaf consumption 0

Excessive lower branch loss Y 15,19 Other symptom 0

Neighbour tree: Tree vigour:

Number of neighbours 1 1,2 1. Good ⃝

Crown interlocking 1 1,2 2. Average ❷ 4,12

Stem grafting 0 3. Poor ⃝

Growth restriction:

1. Building: wall side N MAIN SCAFFOLD

2. Building: opposite side N Stem co-dominance:

3. Fence N 1. Single stem ⃝

4. Other N 2. Multipe stems: one dominant ❷ 5,6

Foliage density: 3. Two co-dominant ⃝

1. Normal ❶ 2 4. Over two co-dominant ⃝

2. Sparse ⃝ Trunk base position:

Leaf size: 1. Wall crest ❶ 7

1. Normal ❶ 11,12 2. Wall face ⃝

2. Small ⃝ 3. Wall toe ⃝

Leaf colour: Other defects:

1. Normal ❶ 11,12 Gap in crown N

2. Chorotic ⃝ Suspended deadwood N

3. Brown (>5% wilting) ⃝ Vascular epiphytic/parasitic growth:

Abundance 0

Type NA



Table 3-p. 4

D: WALL TREE SURVEY 2011

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TRUNK

NOTABLE DEFECTS CRITICAL DEFECTS

Trunk curvature: Trunk code 0

Curved trunk with code 0 Defect type:

Meandering trunk with code 0 1. Canker ⃝

Trunk base & taper: 2. Decay without fruiting body ⃝

Inadequate taper 0 3. Decay with fruiting body ⃝

Limited tension wood 0 4. Cavity ⃝

Basal detachment from wall 0 Position & dimension:

Bark symptoms: Position (basal, middle, terminal) 0

Increment strip N Length (10 cm) 0

Loosened or detached N Width (10 cm) 0

Kinked or buckled N Depth (10 cm) 0

Darkened N Response wood:

Wet N Woundwood formation N

Other surficial symptoms: Bulge wood formation N

Wound with decay Y 5,13,15

Lightning scar N Trunk code 0

Bleeding or sap flow N Defect type:

Galls N 1. Canker ⃝

Girdling wire/rope N 2. Decay without fruiting body ⃝

Penetrative symptoms: 3. Decay with fruiting body ⃝

Crack: longitudinal N 4. Cavity ⃝

Crack: transverse N Position & dimension:

Seam N Position (basal, middle, terminal) 0

Pointed rib N Length (10 cm) 0

Bulge N Width (10 cm) 0

Depression/buckle N Depth (10 cm) 0

Biotic invasion symptoms: Response wood:

Termite mud tube N Woundwood formation N

Termite burrowed wood N Bulge wood formation N

Borer ingress or exit holes N




Defect position (three stem segments): 1. First (basal) 1/3 2. Second (middle) 1/3 3. Third (terminal) 1/3

Length, width and depth of defect: 1. 10 cm

Table 3-p. 5

E: WALL TREE SURVEY 2011

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CROTCH (mainly defective first

order)















Other N Other N















Other N Other N


Table 3-p. 6

F: WALL TREE SURVEY 2011

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LIMB & MAIN BRANCH

(defective)

NOTABLE DEFECTS

Stub: Bulge N

With woundwood N Depression/buckle N

Little or no woundwood Y 19, 20 Biotic invasion symptoms:

Jagged end or torn bark N Termite mud tube N

Excessive reduction or decline: Termite burrowed wood N

Topped/tipped Y 15-18 Borer ingress or exit holes N

Broken or hanger N

Dead branch N CRITICAL DEFECTS

Abnormal posture: Defect 0

Bowed downwards N Defect type:

Curved upwards Y 16 1. Canker ⃝

Meandering or kinked N 2. Decay without fruiting body ⃝

Elbow joint Y 16-18 3. Decay with fruiting body ⃝

Opposite N 4. Cavity ⃝

Crowded (>2) N Position & dimension:

Closely spaced Y 18 Position (basal, middle, terminal) 0

Crossed N Length (10 cm) 0

Excessive loading: Width (10 cm) 0

Too long N Depth (10 cm) 0

Too low N Response wood:

Too thick (heavy) N Woundwood formation N

Excessive end load N Bulge wood formation N

Bark symptoms:

Increment strip N Defect 0

Loosened or detached N Defect type:

Kinked or buckled N 1. Canker ⃝

Darkened N 2. Decay without fruiting body ⃝

Wet N 3. Decay with fruiting body ⃝

Other surficial symptoms: 4. Cavity ⃝

Wound with decay Y15-17,

19,20 Position & dimension:

Lightning scar N Position (basal, middle, terminal) 0

Bleeding or sap flow N Length (10 cm) 0

Galls N Width (10 cm) 0

Girdling wire/rope N Depth (10 cm) 0

Penetrative symptoms: Response wood:

Crack: longitudinal shear N Woundwood formation N

Crack: transverse N Bulge wood formation N

Seam N

Pointed rib N



Limb of main branch: include only stems with a diameter >10 cm.

Defect position (three stem segments): 1. First (basal) 1/3 2. Second (middle) 1/3 3. Last (terminal) 1/3

Circumference affected by defect: 1. 40%

Table 3-p. 7

G: WALL TREE SURVEY 2011

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HAZARD ASSESSMENT

SITE AND TREE OVERVIEW HAZARD RATING SCORE

Fall zone target: Probability of failure (A 1-4):

1. Pedestrians Y 1,2 1. Low ❶

2. People gathering spot N 2. Moderate ⃝

3. Open space recreation N 3. High ⃝

4. Vehicle parking N 4. Extremely high ⃝

5. Vehicular traffic Y 1 Size of defective part (B 1-4):

Target management: 1. 750 mm diameter ⃝

Tree part likely to fall: Frequency of use (C 1-4):

1. Whole tree ⃝ 1. Occasional ⃝

2. Trunk/limb ⃝ 2. Intermittent ⃝

3. Branch ❸ 2 3. Frequent ❸

Key risk factor assessment: 4. Constant ⃝

Root problems N Risk score (3-12):

Canker N Risk score=A+B+C 5

Decay/cavity Y15-17,

19,20Risk rating:

Crack N 1. Very low (score=3) ⃝

Weak branch union N 2. Low (score=4-6) ❷

Poor tree architecture Y 16-18 3. Medium (score=7-9) ⃝

Dead wood N 4. High (score=10-12) ⃝

Wind exposure: Additional risk factor (D 0-2):

1. Single tree ⃝ Factor 1 0

2. Emergent tree ⃝ Factor 2 0

3. Tree group: edge ❸ 1

4. Tree group: not edge ⃝

5. Recently exposed tree ⃝


Risk score: Sum the scores of A, B and C and insert the result.

Additiona risk factor: Insert a brief description of the additional risk factor.

Table 3-p. 8


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RECOMMENDATIONS

DIAGNOSIS & TREATMENT 6. Remove hanger 0

A. Internal decay/shell investigation: 7. Trim selected wounds 1 15-17

1. Microdrilling 0 H. Supplementary support:

2. Sonic tomograph 0 1. Cable bracing 0

3. Close visual & mallet inspection 0 18 2. Rod bracing 0

B. Pest-disease diagnosis/treatment: 3. Propping 0

1. Exterminate termite 0 I. Protection against construction:

2. Identify pest or pathogen 0 1. Establish tree protection zone 0

3. Apply control and treatment 0 2. Establish soil protection zone 0

CORRECTIVE-PREVENTIVE PRUNING 3. Evaluate groundwater impact 0

C. Pruning-reduction: 4. Prevent incursion 0

1. Reduce crown height 0 5. Support wall 0

2. Reduce crown spread 0 6. Support tree 0

3. Reduce crown weight 0 7. Preventive tree treatment 0

4. Balance the crown 0 8. Institute monitoring 0

D. Pruning-trimming J. Remove tree:

1. Trim broken branch 0 1. Establish justifications 0

2. Thin the crown 0 2. Prepare felling application 0

3. Trim crossed/competing branch 2? 18 K. Other recommended actions:

4. Trim defective branch 1 13,14,17 1. OVT nomination 0

5. Trim branch end weight 0 2. Install information plaque 0

E. Pruning-removal 3. Inspection frequency (months) 12



3. Remove stubs 1 20 L. Ameliorate growth limitations:

4. Remove selected epicormics 0 1. Ameliorate stem limitations 0

5. Remove selected sprouts 0 2. Ameliorate root limitations 1 7

6. Remove dead surface roots 0 3. Manage aerial roots 0

F. Pruning-maintain clearance M. Wall treatment:

1. Footpath 0 1. Remove joint seals 1 7

2. Carriageway 0 2. Remove obsolete installations 0

3. Adjacent building 0 3. Remove weep hole rubbish 0

4. Opposite building 0 4. Repair leaking pipes 0

TREE MANAGEMENT N. Soil treatment:

G. Tree cleaning: 1. Install soil strip at toe 1 7

1. Remove surface root rubbish 0 2. Install soil strip at crest 1 17

2. Removing girdling wire/rope 0 3. Widen soil strip at toe 0

3. Remove embedded objects 0 4. Widen soil strip at crest 0

4. Remove crotch debris 0 5. Improve soil at toe 0

5. Remove hanging rubbish 0 6. Improve soil at crest 0


Table 3-p. 9


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EXPLANATIONS OF

RECOMMENDATIONS

16,17,

18

18

13,14

16,17

19

15-17

20

7

D4. Trim defective branch: The remnant part of trunk A, which was snapped in the past, has lost all

its natural branches and is harbouring only a small number of feeble sprouts mainly at its broken end.

The tip has an uneven surface and has developed rather advanced decay. The trunk tilts heavily

towards the east and it gets rather close to the trunk of its neighbour T4. Not playing a functional

role in the overall scheme of the tree, it is recommended for removal by cutting at its base, taking

care to minimize injury of adjacent trunk B and associated lignified aerial roots.

E3. Remove stubs: The stub with decay should be removed using the standard removal cut at the

fork with the parent stem.

G7. Trim selected wounds: The wounds with jagged edges or an uneven surface or decayed wood

should be very carefully trimmed using a sharp arborist manual saw with the help of a chisel.

However, the well-formed callus tissues should as far as practicable be left undisturbed.

L2. Ameliorate root limitations: The limitations to root growth due to the lack of open and

penetrable joints between masonry blocks, and the lack of accessible soil at the wall toe and crest

positions, could be ameliorated to enhance tree growth and performance.

G7. Trim selected wounds: The terminal end of the stem C stump with advanced decay should be cut

away, but the lignified aerial root linking stem C to stem B above should not be cut.

A3. Close visual & mallet inspection: Inspect at close quarters the condition and extent of decay or

structural weakness at the branch truncation wound that is supporting several elongated epicormic

branches.

D4. Trim defective branch: The evaluation of the cut wound at close quarters recommended under

A3 should inform whether the decayed tip of the parent branch has sufficient sound wood to hold

the epicormic branch. If not, the daughter branch should be shortened by reduction cut. The

amount to be removed shall correspond to the condition of the wood around the cut face.

D3. Trim crossed/competing branch: The crowded branching habit could be partly relieved by

removing one of the three parallel branches. The close evaluation recommended under A3 should

inform whether the decayed tip of the parent branch has sufficient sound wood to hold the

epicormic branches. If not, the daughter branches should be shortened by reduction cut. The

amount to be removed shall correspond to the condition of the wood around the cut face.

7

7

17

M1. Remove joint seals: The joints between masonry blocks have been sealed recently by cement,

thus stopping their penetration by tree roots. The rigid cement seal also restricts expansion of

existing roots and may cause injurious girdling as they continue to thicken. Where the roots are

physically obstructed, consideration could be given to localized removal of the cement seal to permit

some new roots to grow into the joints and existing roots to expand.

N1. Install soil strip at toe: An open soil strip filled with a good-quality soil mix could be installed at

the wall toe at Bonham Road, in lieu of the existing drainage u-channel, to allow growth of roots in

the soil below the pavement. To preserve the walkable width at the narrow pavement and to avoid

human-foot trampling of soil, a metal grille could be placed on the soil surface. The advice of a

geotechnical should be sought in the design of this soil strip. If a continuous soil strip is not feasible,

an intermitted strip could be adopted instead.

N2. Install soil strip at crest: An open soil strip filled with a good-quality soil mix could be installed at

the wall crest to allow growth of roots in the soil below the pavement at St Stephen's Lane. A

segment of the existing stone parapet wall will have to be replaced by railing to permit the roots to

reach this new soil strip. To preserve the walkable width at the narrow lane and to avoid human-foot

trampling of soil, a metal grille could be placed on the soil surface. The advice of a geotechnical

should be sought in the design of this soil strip. If a continuous soil strip is not feasible, an

intermitted strip could be adopted instead.

Table 4. Stonewall tree assessment results of T4. Table 4‐p. 1


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SITE & DIMENSIONSBasic information: Height attribute (m):Tree reference no. Wall height 2.78 1,6Tree register no. Trunk base elevation 2.78 1,6Species First branch height 3.64 2Species (Chinese) Tree height 14.83 2Tree age classOVT code Crown radius (m):Map ref Crown radius // left 12.14 4Survey date Crown radius // right 3.52 4Assessor Crown radius ┴ front 14.53 2Last inspection date Crown radius ┴ back 4.18 2

Wall or slope ID: Trunk DBH (cm):SIMAR slope # Trunk A A1: 38 A2: 38 4,5Slope ID Trunk B 55 4,5

Trunk CLocation information: Trunk DStreet Trunk ELocation 1 Trunk FLocation 2 Sum 55Nearby utility post Aggregate 77

Tree lean (deg) A 52, B ‐49 2Adjacent landuse:Landuse at toe Wall condition at trunk base:Landuse at crest Masonry block Intact Cracked Shifted 6Development density

Root spread on wall:Adjacent building at crest: Lateral spread (m) 8.99 6Building storey Vertical spread (m) 2.78 6Construction activities

Environment:Solar accessAir qualityWind exposure

Landuse: 1. Residential 2. Government institutional community 3. Commercial 4. Open space 5. Slope 6. OtherCrown radius: left and right are reckoned with the assessor facing the wall.


Low Medium High Low Medium High

Low Medium High

1 2 3 4 5 6 1 2 3 4 5 6 Low Medium High

30 N Y

Bonham RoadSt Stephen's Lane

31757

Y

C.Y.JimD M Y

11SW‐A/R577

11SW‐A/R577

NA

6/Jun/2012

T004

Ficus microcarpa細葉榕


Table 4‐p. 2

B: WALL TREE SURVEY 2011 Rating

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ROOTSWALL SURFACE ROOTS Biotic invasion symptoms:Spreading geometry: Termite mud tube N1. No spread (

Table 4‐p. 3

C: WALL TREE SURVEY 2011 Rating

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CROWN & MAIN SCAFFOLDCROWNLive crown size: Twig dieback:1. Low 50% ⃝Asymmetric crown Y 1 Abnormal growth:Topped crown N Water sprouts 1 5Tipped crown Y 4 Epicormic branch 0Excessive reduction: Pest & disease:Excessively thinned crown N Leaf consumption 0Excessive lower branch loss Y 2 Other symptom 0Neighbour tree: Tree vigour:Number of neighbours 2 1 1. Good ⃝Crown interlocking 2 2,3 2. Average ❷ 2Stem grafting 0 3. Poor ⃝Growth restriction:1. Building: wall side N MAIN SCAFFOLD2. Building: opposite side N Stem co‐dominance:3. Fence N 1. Single stem ⃝4. Other N 2. Multipe stems: one dominant ⃝Foliage density: 3. Two co‐dominant ❸ 51. Normal ⃝ 4. Over two co‐dominant ⃝2. Sparse ❷ 18 Trunk base position:Leaf size: 1. Wall crest ❶ 21. Normal ❶ 18 2. Wall face ⃝2. Small ⃝ 3. Wall toe ⃝Leaf colour: Other defects:1. Normal ❶ 18 Gap in crown Y 12. Chorotic ⃝ Suspended deadwood N3. Brown (>5% wilting) ⃝ Vascular epiphytic/parasitic growth:

Abundance 0Type NA



Table 4‐p. 4


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TRUNKNOTABLE DEFECTS CRITICAL DEFECTSTrunk curvature: Trunk code 0Curved trunk with code 0 Defect type:Meandering trunk with code A 25‐26 1. Canker ⃝Trunk base & taper: 2. Decay without fruiting body ⃝Inadequate taper 1 4 3. Decay with fruiting body ⃝Limited tension wood 0 4. Cavity ⃝Basal detachment from wall 3 9‐13 Position & dimension:Bark symptoms: Position (basal, middle, terminal) 0Increment strip N Length (10 cm) 0Loosened or detached N Width (10 cm) 0Kinked or buckled N Depth (10 cm) 0Darkened N Response wood:Wet N Woundwood formation NOther surficial symptoms: Bulge wood formation NWound with decay Y 21‐24, 27Lightning scar N Trunk code 0Bleeding or sap flow N Defect type:Galls N 1. Canker ⃝Girdling wire/rope N 2. Decay without fruiting body ⃝Penetrative symptoms: 3. Decay with fruiting body ⃝Crack: longitudinal N 4. Cavity ⃝Crack: transverse N Position & dimension:Seam N Position (basal, middle, terminal) 0Pointed rib N Length (10 cm) 0Bulge N Width (10 cm) 0Depression/buckle N Depth (10 cm) 0Biotic invasion symptoms: Response wood:Termite mud tube N Woundwood formation NTermite burrowed wood N Bulge wood formation NBorer ingress or exit holes N





Table 4‐p. 5

E: WALL TREE SURVEY 2011 Rating

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CROTCH (mainly defective first order)Trunk code of crotch 0 Trunk code of crotch 0Defect type: Defect type:V‐crotch incipient state N V‐crotch incipient state N V‐crotch with included bark N V‐crotch with included bark N V‐crotch with ear N V‐crotch with ear N V‐crotch with decay N V‐crotch with decay N V‐crotch with cavity N V‐crotch with cavity N V‐crotch with split stem N V‐crotch with split stem N Related symptoms: Related symptoms:Crotch with sap flow N Crotch with sap flow N Crotch with darkened bark N Crotch with darkened bark N Bark crease underneath N Bark crease underneath N Debris accumulation N Debris accumulation N Water pocket N Water pocket N Other N Other N

Trunk code of crotch 0 Trunk code of crotch 0Defect type: Defect type:V‐crotch incipient state N V‐crotch incipient state N V‐crotch with included bark N V‐crotch with included bark N V‐crotch with ear N V‐crotch with ear N V‐crotch with decay N V‐crotch with decay N V‐crotch with cavity N V‐crotch with cavity N V‐crotch with split stem N V‐crotch with split stem N Related symptoms: Related symptoms:Crotch with sap flow N Crotch with sap flow N Crotch with darkened bark N Crotch with darkened bark N Bark crease underneath N Bark crease underneath N Debris accumulation N Debris accumulation N Water pocket N Water pocket N Other N Other N


Table 4‐p. 6

F: WALL TREE SURVEY 2011 Rating

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LIMB & MAIN BRANCH (defective)NOTABLE DEFECTSStub: Bulge NWith woundwood N Depression/buckle NLittle or no woundwood N Biotic invasion symptoms:Jagged end or torn bark Y 20,28 Termite mud tube NExcessive reduction or decline: Termite burrowed wood NTopped/tipped Y 15 Borer ingress or exit holes NBroken or hanger NDead branch N CRITICAL DEFECTSAbnormal posture: Defect 0Bowed downwards Y 15,18 Defect type:Curved upwards N 1. Canker ⃝Meandering or kinked N 2. Decay without fruiting body ⃝Elbow joint Y 16,19 3. Decay with fruiting body ⃝Opposite N 4. Cavity ⃝Crowded (>2) N Position & dimension:Closely spaced N Position (basal, middle, terminal) 0Crossed N Length (10 cm) 0Excessive loading: Width (10 cm) 0Too long N Depth (10 cm) 0Too low N Response wood:Too thick (heavy) N Woundwood formation NExcessive end load N Bulge wood formation NBark symptoms:Increment strip N Defect 0Loosened or detached N Defect type:Kinked or buckled N 1. Canker ⃝Darkened N 2. Decay without fruiting body ⃝Wet N 3. Decay with fruiting body ⃝Other surficial symptoms: 4. Cavity ⃝Wound with decay Y 18,19 Position & dimension:Lightning scar N Position (basal, middle, terminal) 0Bleeding or sap flow N Length (10 cm) 0Galls N Width (10 cm) 0Girdling wire/rope N Depth (10 cm) 0Penetrative symptoms: Response wood:Crack: longitudinal shear N Woundwood formation NCrack: transverse N Bulge wood formation NSeam NPointed rib N



Limb of main branch: include only stems with a diameter >10 cm.Defect position (three stem segments): 1. First (basal) 1/3 2. Second (middle) 1/3 3. Last (terminal) 1/3Circumference affected by defect: 1. 40%

Table 4‐p. 7

G: WALL TREE SURVEY 2011 Rating

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HAZARD ASSESSMENT SITE AND TREE OVERVIEW HAZARD RATING SCOREFall zone target: Probability of failure (A 1‐4):1. Pedestrians Y 1 1. Low ⃝2. People gathering spot N 2. Moderate ⃝3. Open space recreation N 3. High ❸4. Vehicle parking N 4. Extremely high ⃝5. Vehicular traffic Y 1 Size of defective part (B 1‐4):Target management: 1. 750 mm diameter ⃝Tree part likely to fall: Frequency of use (C 1‐4):1. Whole tree ❶ 8‐12 1. Occasional ⃝2. Trunk/limb ⃝ 2. Intermittent ⃝3. Branch ⃝ 3. Frequent ❸Key risk factor assessment: 4. Constant ⃝Root problems Y 8‐12 Risk score (3‐12):Canker N Risk score=A+B+C 9Decay/cavity N Risk rating:Crack N 1. Very low (score=3) ⃝Weak branch union N 2. Low (score=4‐6) ⃝Poor tree architecture Y 3. Medium (score=7‐9) ❸Dead wood N 4. High (score=10‐12) ⃝Wind exposure: Additional risk factor (D 0‐2):1. Single tree ⃝ Factor 1 Root detachment from wall 1 8‐122. Emergent tree ⃝ Factor 2 03. Tree group: edge ⃝4. Tree group: not edge ❹5. Recently exposed tree ⃝


Risk score: Sum the scores of A, B and C and insert the result.Additiona risk factor: Insert a brief description of the additional risk factor.

Table 4‐p. 8


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RECOMMENDATIONSDIAGNOSIS & TREATMENT 6. Remove hanger 0A. Internal decay/shell investigation: 7. Trim selected wounds 2 19‐21,231. Microdrilling 3 18 H. Supplementary support:2. Sonic tomograph 0 1. Cable bracing 3 1,29

3. Close visual & mallet inspection 2 15,16,19 2. Rod bracing 0

B. Pest‐disease diagnosis/treatment: 3. Propping 3 1,251. Exterminate termite 0 I. Protection against construction:2. Identify pest or pathogen 0 1. Establish tree protection zone 03. Apply control and treatment 0 2. Establish soil protection zone 0CORRECTIVE‐PREVENTIVE PRUNING 3. Evaluate groundwater impact 0C. Pruning‐reduction: 4. Prevent incursion 01. Reduce crown height 0 5. Support wall 02. Reduce crown spread 0 6. Support tree 03. Reduce crown weight 0 7. Preventive tree treatment 04. Balance the crown 0 8. Institute monitoring 0D. Pruning‐trimming J. Remove tree:1. Trim broken branch 0 1. Establish justifications 02. Thin the crown 0 2. Prepare felling application 03. Trim crossed/competing branch 2? 18 K. Other recommended actions:4. Trim defective branch 0 1. OVT nomination 05. Trim branch end weight 2? 15,16 2. Install information plaque 0E. Pruning‐removal 3. Inspection frequency (months) 12



3. Remove stubs 2 20,24,27,28 L. Ameliorate growth limitations:

4. Remove selected epicormics 2? 19 1. Ameliorate stem limitations 05. Remove selected sprouts 0 2. Ameliorate root limitations 1 76. Remove dead surface roots 0 3. Manage aerial roots 0F. Pruning‐maintain clearance M. Wall treatment:1. Footpath 0 1. Remove joint seals 02. Carriageway 0 2. Remove obsolete installations 1 133. Adjacent building 0 3. Remove weep hole rubbish 04. Opposite building 0 4. Repair leaking pipes 0TREE MANAGEMENT N. Soil treatment:G. Tree cleaning: 1. Install soil strip at toe 1 71. Remove surface root rubbish 2 12 2. Install soil strip at crest 1 5,102. Removing girdling wire/rope 0 3. Widen soil strip at toe 03. Remove embedded objects 0 4. Widen soil strip at crest 04. Remove crotch debris 0 5. Improve soil at toe 05. Remove hanging rubbish 1 17 6. Improve soil at crest 0


Table 4‐p. 9


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EXPLANATIONS OF RECOMMENDATIONS

18

15,16,19

18

15,16

20,24,27,28

19

12

17

A1. Microdrilling: The condition and extent of decay of the wound at the crotch should be probed with the help of microdrilling.

D3. Trim crossed/competing branch: The microdrilling evaluation recommended under A1 found sufficient sound wood at and near the critical crotch position to hold the two thick branches and the thinner and elongated epicormic branch. It is not necessary to remove the load on the branch.

D5. Trim branch end weight: The evaluation at close quarters recommended under A3 should inform whether the tip of the parent branch has sufficient sound wood to hold the rather heavy epicormic replacement branch. If not, the end weight of the daughter branch should be reduced by removing some of the small branches. The amount to be removed shall be commensurate with the condition of the wood around the cut face.

A3. Close visual & mallet inspection: Inspect at close quarters the condition and extent of decay or structural weakness at the branch truncation wounds that support elongated epicormic branches.

E4. Remove selected epicormics: Evaluation at close quarters recommended under A3 should inform whether the broken end of the branch has sufficient sound wood to hold the two closely spaced epicormic branches. If not, the load on the parent stem should be reduced by an amount that is commensurate with the condition and quantity of sound wood around the wound. From slight to severe loss of wood mechanical strength, the following sequence of actions could be adopted: shorten the thin branch, remove the thin branch, shorten the thick branch, and remove the thick branch.

G5. Remove hanging rubbish: The rubbish that hangs on the branches of the tree should be carefully extricated and removed in the course of pruning with the help of a hydraulic platform.

G1. Remove surface root rubbish: The rubbish that has deposited on the surface roots and the adjacent trunk base, together with the leaf litter, should be regularly removed with the help of a brush to avoid moisture accumulation which could induce decay at the critical trunk base position. More importantly, objects trapped in the wedge gap caused by the detachment of the tree from the wall could aggravate the detachment process due to the wedging effect. They must be diligently and thoroughly removed from the gap to prevent aggravation of the detachment risk.

E3. Remove stubs: The stubs with decay should be removed using the standard removal cut at the fork with the parent stem.

19‐21, 23

1,29

1,29H1. Cable bracing (Method B): If permission could not be obtained in implement Method A cable bracing system, the less desirable alternative is to install a strong steel frame near and parallel to the parapet wall at St Stephen's Lane to hold the tree. The frame should be firmly anchored in the ground. Cables can then be installed to link the frame to the two trunks. Due to the low bracing position relative to tree height, the amount of swing in the wind would be rather limited. Thus the cable should have a correspondingly lower degree of elasticity. As the Lane is used for vehicular access, the frame has to be positioned as near as possible to the parapet wall to maintain sufficient vehicular lateral clearance. It implies that excavation will have to be conducted near the tree which may harm the roots that have penetrated the soil lying below the Lane. To minimize this impact, the positions of the two anchors for the frame could be placed respectively between T4 and T3, and T4 and T5. Moreover, the impact could also be reduced by developing a technique with the help of an engineer to install the anchors with a minimum excavation limit. Please see the attached drawing (Photo T4‐31) to illustrate the concept design of this alternative cable bracing system. The detailed design should be elaborated in conjunction with a structural engineer.

G7. Trim selected wounds: The wounds with jagged edges or an uneven surface or decayed wood should be very carefully trimmed using a sharp arborist manual saw with the help of a chisel. However, the well‐formed callus tissues should as far as practicable be left undistu

Documents

Table 1. Stonewall tree assessment results of T1. Table 1-p. 1 A: … · 2015. 11. 10. · Bleeding or sap flow N Defect type: Galls N 1. Canker ⃝ Girdling wire/rope N 2. Decay