A tree survey
and assessment was conducted at proposed Pui O Tunnel Portal (Section 2a) and Tai Long Wan east
Landfall Area (Section 43a) only.
In total 87 trees were identified. Summary of trees in conflict with the
captioned works and their possible treatment are shown in Table I-1:
Table I-1 Summary
of Tree Survey at Pui O Tunnel Portal and Tai Long Wan East Landfall Area
|
Description
& Possible Treatment |
Quantity |
Remark |
|
Total number of tree
surveyed |
87 Nr. |
- |
|
Tree proposed to be felled |
38 |
Conflict
with construction work |
|
Tree proposed to be
retained |
49 |
- |
|
Tree proposed to be
transplanted |
0 Nr. |
- |
|
Protected species |
Aphyllorchis montana (Orchid) |
2 colony (approx.200 number) |
A protected
orchid species, Aphyllorchis montana
was found in the proposed Pui O Portal (Section 2a).
It comprises two colonies. For detail assessment refer to the Tree
Survey ScheduleReport
for Pui O Portal and Tai Long Landfall Area.
A tree identification survey of the captioned site was carried out by New Era in September 2001. Majority of the tree species are commonly found in Hong Kong. No protected tree species was identified.
I1.3 Legend
The written report includes the following information on each tree surveyed.
|
Information |
Description |
|
Tree number |
determined by Land Surveyors and the corresponding number to the tree were indicated on the
topographical plan |
|
Species |
the
botanical name are
used |
|
Trunk diameter |
in
meter, taken at 1000 mm height above ground level (multi-trunks tree will be
measured with the biggest sized trunk) |
|
Height |
in
meters, taken from ground level to the top of tree |
|
Crown spread |
in
meters |
|
Health and condition |
graded
in Good, Fair, or Poor |
|
Form and Style |
graded
in Good, Fair, or Poor |
|
Amenity Value |
graded
in High, Medium, or Low |
|
Conflict with Development |
stated
in Yes, or No |
|
Transplantability |
stated
in Yes, or No |
|
Proposed
treatment |
recommendation
for tree’s future status, stated in Retain, Fell or Transplant |
|
Brief comments |
brief
description on tree such as leaning
trunk etc... Tree with more than one trunk will be described as double
trunks, triple trunks and so forth |
I1.4 Assessment of Health/Condition, Form/Style,
and Amenity Value
Health and condition
Assessment of the tree health and
condition involves inspection for the following:
a) Foliage
· color and general appearance
· insect and fungal infection
b) Branches
· inspect for dead or die-back or crossing branches
· any heavy horizontal branch which may cause tree unstable
· damaged, broken or cut branches
· insect and fungal infection on branches
· special phenomena of the branches
c) Trunk
· tightly forked or multi-ascending trunk is a sign of weakness in trees
· cavities or internal/external rot
· sap seeping through the trunk
· fungi growing on the trunk
· inspect for any cavity or serious bark damage
Assessment of the tree health and
condition involves inspection for the above features and classification as
follows:
G = Good: trees with a low incidence of the less serious features listed above and a high chance of a fast recovery from such features.
F = Fair: trees with a higher incidence of the less serious features and a medium chance of recovery.
P = Poor: trees with more serious health features and with a low chance of recovery, even with remedial measures.
Tree form and style
Assessment for tree form is classified as
follows:
G = Good: trees with well-balanced form, upright, evenly branching, well-formed head and generally in accordance with the standard form for its species.
F = Fair: trees with generally balanced form with natural compensations for loss of branches or leaning trunks.
P = Poor: trees with very unbalanced form, leaning, contorted, bending trunk, suffering from loss of major branches with general damage and growing close to adjacent trees.
Amenity value:
the significance of tree is expressed as “Amenity value”. It is graded High (H), Medium (M) and Low(L) with (H) as the highest grade and (L) the lowest. Factors that take into consideration in the assessment include:
Conservation value:
rare or
protected species, as listed by the Agriculture, Fisheries and Conservation
Department. Fung shui significance is also taken into account.
Functional value:
provide screening, shade or shelter.
Visual impact:
adverse impact as a result of loss of tree.
Status & form:
a good specimen of its species, maturity, present condition, potentially hazardous and stability. The grading indicates the following qualities in tree:
· H High: Rare or protected species, fung shui significance or has high visual impact with good health condition and form.
· M Medium: Common species with average health, medium condition and acceptable form. Rare or protected species, fung shui significance or high visual impact with poor health condition and form.
· L Low: Little or non-functional common species with poor health condition and poor form.
I1.5 Statement of Transplantable and Proposed Ttreatment
Generally, the Landscape Architect, who
possessed of thorough understanding of building layout of the relevant project,
will determine on treatment of trees.
However, the following information is provided for general understanding
on the three treatments of trees.
·
Transplant:
Trees with high amenity value are recommended to transplant. Trees approved to be transplanted will be
relocated to a suitable location with the consent of government.
·
Fell:
Trees in direct conflict with the slope safety measure work will be felled,
however, decision should be reconfirmed on site by engineer’s representative.
·
Retain:
Trees in unaffected areas are recommended to retain and will be protected
during construction.
Nevertheless, the Landscape Architect will incorporate those transplanted and retained trees into the future Landscape Master Plan.
Assessment of the transplantibility and proposed future status are classify as follows:
R Retain: The feasibility of tree
retaining has been considered with regard to the following:
· Proximity to the area of re-stabilization and potential damaged to the trees as a result of the work.
·
Changes
to ground levels on a macro scale that affects the ground water table and may
cause severe stress.
·
Special construction to maintain the
existing ground level is also considered.
· Conflict between tree roots and slope stabilization method.
T Transplant: In situation where
it is impossible to retain trees, then trees are considered to be
transplanted. The criteria upon which
the assessment of transplanting trees is base included the following:
· Rarity of species: rare Hong Kong species are particularly considered.
· Condition of tree: tree with balanced form, good health and high amenity value.
· Maturity: basically, younger trees have higher survival rate while mature trees do not.
· Species character: different tree species have different rates of survival.
· Rootball feasibility: tree growing on loosen rocky sub-base / slope or adjacent to important utility will not be considered
·
Access: heavy machinery may be required
to lift up the tree steep slope, and rocky terrain may make the operation
impossible.
F Fell: Trees in direct conflict with the construction work; change of level etc… shall be considered in term of species, health, condition and amenity value. Dead, hazardous or trees with contiguous disease are also proposed to be felled. Woodland trees which have had adjacent tree removal and have unbalanced form or which are at risk of being blown over due to loss of supporting are considered for felling.
I1.6 Tree Survey Schedule (For Pui O Tunnel
Portal Area and Tai Long Wan Landfall Area Only)
|
TREE
NO. |
SPECIES |
TRUNK DIA. (M) |
OVERALL HEIGHT (M) |
AVERAGE SPREAD (M) |
HEALTH CONDIT'N (G/F/P) |
FORM STYLE (G/F/P) |
AMENITY VALUE (H/M/L) |
CONFLICT W/ DEVELOP'M (Y/N) |
TRANS- PLANTABLE (Y/N) |
PROPOSED TREATMENT (R/T/F) |
BRIEF
DESCRIPTION / COMMENT |
|
1 |
Sterculia
lanceolata |
0.12 |
6 |
4 |
F |
F |
M |
N |
N |
R |
forked leaning trunk |
|
2 |
Sterculia
lanceolata |
0.15 |
5 |
3 |
F |
F |
M |
N |
N |
R |
broken branches twisted by climbers |
|
3 |
Sterculia
lanceolata |
0.2 |
5 |
5 |
F |
P |
M |
N |
N |
R |
forked leaning trunk |
|
4 |
Aquilaria
sinensis |
0.12 |
4 |
4 |
F |
P |
M |
N |
N |
R |
horizontal trunk |
|
5 |
Schefflera
octophylla |
0.18 |
8 |
8 |
F |
F |
M |
N |
N |
R |
forked multi trunk |
|
6 |
Aquilaria
sinensis |
0.12 |
3 |
2 |
P |
P |
M |
N |
N |
R |
contorted trunk twisted by climbers |
|
7 |
Artocarpus
hypargyrea |
0.1 |
4 |
2 |
F |
P |
M |
N |
N |
R |
leaning trunk covered by climbers |
|
14 |
Schefflera
octophylla |
0.18 |
5 |
4 |
F |
F |
M |
N |
N |
R |
leaning trunk covered by climbers |
|
15 |
Sapium
discolor |
0.1 |
4 |
3 |
F |
F |
M |
N |
N |
R |
contorted leaning trunk |
|
16 |
Rhus
succedanea |
0.1 |
5 |
4 |
F |
P |
M |
N |
N |
R |
double leaning trunk covered by climbers |
|
17 |
Casuarina
equisetifolia |
0.1 |
7 |
3 |
F |
F |
M |
Y |
N |
F |
multi trunk |
|
18 |
Casuarina
equisetifolia |
0.2 |
9 |
5 |
F |
F |
M |
Y |
N |
F |
- |
|
19 |
Casuarina
equisetifolia |
0.2 |
10 |
4 |
F |
F |
M |
Y |
N |
F |
- |
|
20 |
Casuarina
equisetifolia |
0.18 |
8 |
4 |
F |
F |
M |
Y |
N |
F |
- |
|
21 |
Casuarina
equisetifolia |
0.15 |
7 |
4 |
F |
F |
M |
Y |
N |
F |
- |
|
22 |
Casuarina
equisetifolia |
0.2 |
9 |
4 |
F |
F |
M |
Y |
N |
F |
- |
|
23 |
Casuarina
equisetifolia |
0.22 |
10 |
4 |
F |
F |
M |
Y |
N |
F |
- |
|
24 |
Casuarina
equisetifolia |
0.28 |
12 |
7 |
F |
F |
M |
Y |
N |
F |
twisted by climbers |
|
25 |
Casuarina
equisetifolia |
0.1 |
7 |
3 |
F |
F |
M |
Y |
N |
F |
contorted leaning trunk twisted by climbers |
|
26 |
Casuarina
equisetifolia |
0.22 |
10 |
5 |
F |
F |
M |
Y |
N |
F |
twisted by climbers |
|
27 |
Casuarina
equisetifolia |
0.25 |
10 |
6 |
F |
P |
M |
Y |
N |
F |
contorted leaning trunk twisted by climbers |
|
28 |
Casuarina
equisetifolia |
0.22 |
9 |
8 |
P |
P |
M |
Y |
N |
F |
leaning trunk covered by climbers |
|
29 |
Schefflera
octophylla |
<0.095 |
4 |
2 |
F |
F |
M |
Y |
N |
F |
leaning trunk |
|
30 |
Bredelia
tomentosa |
0.1 |
5 |
2 |
P |
P |
M |
Y |
N |
F |
contorted leaning trunk twisted by climbers |
|
31 |
Aquilaria
sinensis |
0.2 |
8 |
4 |
F |
F |
M |
Y |
N |
F |
twisted by climbers |
|
32 |
Casuarina
equisetifolia |
0.15 |
6 |
3 |
P |
P |
M |
N |
N |
R |
leaning trunk covered by climbers |
|
33 |
Casuarina
equisetifolia |
0.1 |
3 |
2 |
P |
P |
M |
Y |
N |
F |
bending trunk twisted by climbers |
|
34 |
Casuarina
equisetifolia |
0.15 |
9 |
3 |
F |
P |
M |
N |
N |
R |
unbalanced crown twisted by climbers |
|
35 |
Casuarina
equisetifolia |
0.12 |
7 |
3 |
F |
F |
M |
N |
N |
R |
contorted trunk twisted by climbers |
|
36 |
Casuarina
equisetifolia |
0.25 |
10 |
4 |
F |
F |
M |
N |
N |
R |
twisted by climbers |
|
37 |
Tetradium
glabrifolium |
0.1 |
6 |
4 |
F |
F |
M |
N |
N |
R |
forked trunk twisted by climbers |
|
38 |
Aporusa
dioica |
0.1 |
5 |
3 |
F |
P |
M |
N |
N |
R |
twisted by climbers |
|
39 |
Casuarina
equisetifolia |
0.22 |
10 |
4 |
F |
F |
M |
N |
N |
R |
twisted by climbers |
|
40 |
Sterculia
lanceolata |
<0.095 |
5 |
3 |
F |
F |
M |
N |
N |
R |
twisted by climbers |
|
41 |
Tetradium
glabrifolium |
0.15 |
7 |
4 |
F |
F |
M |
N |
N |
R |
contorted trunk |
|
42 |
Tetradium
glabrifolium |
0.18 |
10 |
7 |
F |
F |
M |
N |
N |
R |
forked triple trunk |
|
43 |
Sapium
discolor |
0.15 |
9 |
7 |
F |
P |
M |
N |
N |
R |
contorted leaning trunk |
|
44 |
Tetradium
glabrifolium |
0.12 |
9 |
6 |
F |
F |
M |
N |
N |
R |
contorted leaning trunk twisted by climbers |
|
64 |
Tetradium
glabrifolium |
0.22 |
9 |
5 |
F |
F |
M |
N |
N |
R |
twisted by climbers |
|
65 |
Tetradium
glabrifolium |
0.15 |
6 |
4 |
F |
F |
M |
N |
N |
R |
contorted leaning trunk twisted by climbers |
|
66 |
Casuarina
equisetifolia |
0.15 |
5 |
4 |
P |
P |
M |
N |
N |
R |
contorted leaning trunk twisted by climbers |
|
67 |
Sapium
discolor |
0.2 |
6 |
6 |
F |
F |
M |
N |
N |
R |
contorted trunk |
|
68 |
Sapium
discolor |
<0.095 |
5 |
3 |
F |
F |
M |
Y |
N |
F |
contorted leaning trunk |
|
69 |
Schefflera
octophylla |
0.18 |
6 |
5 |
F |
F |
M |
Y |
N |
F |
leaning trunk twisted by climbers |
|
70 |
Aporusa
dioica |
<0.095 |
4 |
4 |
F |
P |
M |
Y |
N |
F |
horizontal leaning trunk |
|
71 |
Scolopia
chinensis |
0.15 |
5 |
4 |
F |
F |
M |
Y |
N |
F |
multi trunk |
|
72 |
Dead
tree |
- |
- |
- |
- |
- |
- |
Y |
N |
F |
- |
|
74 |
Sterculia
lanceolata |
<0.095 |
4 |
4 |
F |
F |
M |
N |
N |
R |
double trunk covered by climbers |
|
75 |
Schefflera
octophylla |
<0.095 |
6 |
2 |
F |
F |
M |
N |
N |
R |
leaning trunk twisted by climbers |
|
76 |
Sterculia
lanceolata |
0.1 |
4 |
5 |
F |
F |
M |
N |
N |
R |
growth adjacent to boulder |
|
77 |
Sterculia
lanceolata |
0.15 |
4 |
4 |
F |
F |
M |
N |
N |
R |
contorted trunk twisted by climbers |
|
78 |
Celtis
sinensis |
0.18 |
6 |
6 |
F |
P |
M |
N |
N |
R |
contorted trunk twisted by climbers |
|
79 |
Sapium
sebiferum |
0.12 |
5 |
5 |
P |
P |
M |
N |
N |
R |
contorted trunk twisted by climbers |
|
80 |
Schefflera
octophylla |
0.1 |
5 |
4 |
F |
F |
M |
Y |
N |
F |
leaning trunk twisted by climbers |
|
81 |
Sterculia
lanceolata |
0.1 |
4 |
3 |
F |
F |
M |
Y |
N |
F |
double leaning trunk |
|
82 |
Sterculia
lanceolata |
0.1 |
4 |
3 |
F |
F |
M |
Y |
N |
F |
contorted leaning trunk |
|
83 |
Sterculia
lanceolata |
0.12 |
6 |
3 |
F |
F |
M |
Y |
N |
F |
leaning trunk |
|
84 |
Sinosideroxylon
wightianum |
0.095 |
3 |
3 |
F |
F |
M |
N |
Y |
R |
twisted by climbers |
|
85 |
Schefflera
octophylla |
0.18 |
9 |
9 |
F |
F |
M |
Y |
N |
F |
multi trunk |
|
86 |
Fraxinus
formosana |
0.15 |
9 |
7 |
F |
F |
M |
Y |
N |
F |
leaning trunk |
|
87 |
Schefflera
octophylla |
0.1 |
4 |
2 |
F |
F |
M |
Y |
N |
F |
leaning trunk |
|
88 |
Casuarina
equisetifolia |
0.1 |
5 |
3 |
F |
F |
M |
N |
N |
R |
leaning trunk |
|
89 |
Sapium
discolor |
0.15 |
4 |
4 |
F |
F |
M |
Y |
N |
F |
contorted leaning trunk |
|
90 |
Casuarina
equisetifolia |
0.2 |
9 |
8 |
F |
P |
M |
N |
N |
R |
leaning trunk twisted by climbers |
|
91 |
Pinus
ellioti |
0.15 |
8 |
4 |
F |
F |
M |
N |
N |
R |
contorted trunk |
|
92 |
Casuarina
equisetifolia |
0.28 |
12 |
7 |
F |
F |
M |
N |
N |
R |
forked trunk |
|
93 |
Casuarina
equisetifolia |
0.22 |
10 |
4 |
F |
P |
M |
Y |
N |
F |
twisted by climbers |
|
1001 |
Dimocarpus
longan |
0.1 |
6 |
6 |
F |
F |
M |
N |
N |
R |
leaning trunk twisted by climbers |
|
1004 |
Dead
tree |
- |
- |
- |
- |
- |
- |
|
- |
F |
- |
|
1006 |
Dimocarpus
longan |
<0.095 |
4 |
4 |
F |
F |
M |
N |
N |
R |
leaning trunk |
|
1007 |
Acronychia
pedunculata |
0.12 |
3 |
3 |
F |
F |
M |
Y |
N |
F |
covered by climbers |
|
1008 |
Aporusa
dioica |
0.12 |
4 |
4 |
F |
F |
M |
Y |
N |
F |
unbalanced crown |
|
1009 |
Acronychia
pedunculata |
0.15 |
5 |
5 |
F |
F |
M |
Y |
N |
F |
multi trunk |
|
1010 |
Rhus
succedanea |
0.095 |
5 |
5 |
F |
F |
M |
N |
N |
R |
leaning trunk |
|
1011 |
Machilus
velutina |
0.1 |
5 |
5 |
F |
F |
M |
Y |
N |
F |
leaning trunk covered by climbers |
|
1012 |
Machilus
velutina |
0.12 |
6 |
6 |
F |
F |
M |
Y |
N |
F |
multi trunk |
|
1013 |
Microcos
paniculata |
<0.095 |
3 |
3 |
F |
F |
M |
Y |
N |
F |
contorted leaning trunk twisted by climbers |
|
1014 |
Dimocarpus
longan |
0.1 |
4 |
4 |
F |
F |
M |
N |
N |
R |
contorted leaning trunk twisted by climbers |
|
1015 |
Aporusa
dioica |
0.15 |
6 |
6 |
F |
F |
M |
N |
N |
R |
contorted leaning trunk |
|
1016 |
Artocarpus
hypargyrea |
0.25 |
8 |
8 |
F |
F |
M |
N |
N |
R |
unbalanced crown |
|
1017 |
Dimocarpus
longan |
0.1 |
4 |
4 |
P |
F |
M |
N |
N |
R |
double bending trunk |
|
1018 |
Dimocarpus
longan |
0.1 |
4 |
4 |
P |
F |
M |
N |
N |
R |
contorted leaning trunk twisted by climbers |
|
1019 |
Dimocarpus
longan |
0.1 |
4 |
4 |
P |
F |
M |
N |
N |
R |
contorted leaning trunk twisted by climbers |
|
1020 |
Dimocarpus
longan |
0.1 |
4 |
4 |
P |
F |
M |
N |
N |
R |
contorted leaning trunk twisted by climbers |
|
1021 |
Dimocarpus
longan |
0.1 |
4 |
4 |
P |
F |
M |
N |
N |
R |
contorted leaning trunk twisted by climbers |
|
1022 |
Bredelia
tomentosa |
0.12 |
5 |
5 |
F |
F |
M |
N |
N |
R |
contorted leaning trunk twisted by climbers |
|
1024 |
Ficus
microcarpa |
0.15 |
4 |
4 |
F |
F |
M |
Y |
N |
F |
mounting on boulders |