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Veteran Tree Management Strategy Matthews Green Primary School Site Wokingham Berkshire February 2017 Ref: SCD04048/2017 Prepared on instruction from: Sarah Lee (Construction Contracts Manager) Wokingham Borough Council Report by: Sarah Duckworth DipArb(RFS),TechCert(ArborA),M. Arbor.A, BA (Hons) LANTRA Professional Tree Inspector www.duckworthsarboriculture.co.uk Email: trees@duckworthsarboriculture.co.uk Phone: 0118 327 9775
1 CONTENTS
2 INTRODUCTION ......................................................................................................................................................... 3
2.1 The reasons for producing this Management Strategy ............................................................................... 3
2.2 Planning History ............................................................................................................................................ 3
2.3 Location ......................................................................................................................................................... 4
2.4 Soil .................................................................................................................................................................. 4
2.5 Legal Considerations ..................................................................................................................................... 5
2.6 Protected Species .......................................................................................................................................... 5
2.7 ‘Veteran’ Definition ....................................................................................................................................... 5
3 TREE MANAGEMENT STRATEGY .............................................................................................................................. 7
3.1 Essential Tree Work Operations. .................................................................................................................. 7
3.2 Phenology ...................................................................................................................................................... 8
3.3 Standards of work ......................................................................................................................................... 9
3.4 Monitoring ..................................................................................................................................................... 9
3.5 Surrounding Land Use ................................................................................................................................... 9
3.6 Protection of Tree Roots (Post Development)...........................................................................................10
3.7 New Planting................................................................................................................................................10
3.8 Further Enhancement of biodiversity ........................................................................................................10
4 APPENDICES.............................................................................................................................................................11
A TREE INSPECTION ....................................................................................................................................................12
B INSPECTION NOTES .................................................................................................................................................13
C TREE WORK SCHEDULE ...........................................................................................................................................14
D TEN YEAR MANAGEMENT PLAN .............................................................................................................................15
E PROPOSED LAYOUT (POST DEVELOPMENT) ..........................................................................................................16
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2027
REF. SCD 04048/2017
FEBRUARY 2017 Page 2 of 16
2 INTRODUCTION
2.1 The reasons for producing this Management Strategy
2.1.1 This report has been commissioned by Sarah Lee, Construction Contract Manager for Wokingham
Borough Council. I have been instructed to provide a Veteran Tree Management Strategy which looks at
the present and ongoing management requirements of an Oak which is to be retained within a planned
new School Site within the North Wokingham SDL.
2.1.2 The tree in question is a ‘Veteran’ status Oak (Quercus robur). The tree is an important specimen in terms
of age and size for this species. The tree is one of several Oaks within a wider development site which the
Borough Council seeks to preserve as part of the landscape heritage of the area.
2.1.3 The purpose of this management plan is to demonstrate a clear and practical approach to the retention
of this valuable yet fragile tree within the developed school site. The report will look at the short and long
term management requirements of the tree and with particular reference to its vulnerable rooting area
as well as recommendations for a programme of ongoing inspections and monitoring which will be
appropriate in order to retain the tree in this high occupancy location.
2.1.4 This report is intended to ensure continuity of management over time managing the multiple uses and
potentially conflicting interests of activities on or adjacent to the tree. The plan will need to be reviewed
and revised at intervals to ensure its ongoing effectiveness to address the requirements of the tree and
demands of a busy school site.
2.2 Planning History
2.2.1 The Oak was is one of several visually significant trees included in a Tree Preservation Order in 2012
following the allocation of the site for redevelopment as part of the North Wokingham Strategic
Development Location.
2.2.2 The tree was previously located in an area of arable farmland but, following the redevelopment of the
area, this tree will be located within the grounds of a new school.
2.2.3 In October 2016, the tree was comprehensively surveyed by O.R Booth and M. Skinner of Writtle Forest
Consultancy which included a climbing inspection and assessment of the structural integrity of the tree
using a Tomogram and Resistograph on behalf of Mr. T. Dale of Atkins Global.
2.2.4 The report concluded that, the condition of the tree is such that in order to be retained alongside the
school use, a 20m exclusion zone would be necessary. The implications of this on the ground given its
location and the size of this zone, was that retention makes practical and feasible school use of the site
an untenable proposition.
2.2.5 The proposal was therefore put forward to reduce the tree to a 5m habitat monolith to be retained for
ecological and educational benefit.
2.2.6 Wokingham Borough Council’s Tree and Landscape Team determined that the tree was a Category ‘A’
Veteran tree and the benefits of the tree outweigh its issues. As such, the Borough Council’s Tree and
Landscape Team have therefore requested that the tree be retained as part of the development
proposals.
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2027
REF. SCD 04048/2017
FEBRUARY 2017 Page 3 of 16
2.2.7 To this aim the layout of the site has been revised in order to increase the undeveloped land around the
tree and I have been asked to view the tree and provide a Veteran Tree Management Survey based on
the findings of the Writtle Arboricultural Report and the findings of my own inspection to provide a
measured and appropriate management strategy for the tree.
2.3 Location
Site: Within the grounds of the new ‘Matthews Green’ Primary School.
Grid ref: SU 80474 70187
Owned / Managed by Wokingham Borough Council
2.4 Soil
2.4.1 The British Geological survey 1:50 000 scale bedrock geology description for the site is London Clay
Formation consisting of Clay, Silt and Sand. This is a sedimentary Bedrock formed approximately 34 to 56
million years ago in an environment previously dominated by deep seas.
2.4.2 London Clay soils have a capacity to shrink and swell with changing moisture levels and are also prone to
compaction. They are also less vulnerable to erosion, desiccation and leaching of nutrients.
2.4.3 On site the tree is protected by Tree Protection fencing out to the canopy line only. The area to the north
west of the tree is under water. Outside of the construction exclusion zone the clay is very apparent and
has been churned up by heavy plant within the development site.
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2027
REF. SCD 04048/2017
FEBRUARY 2017 Page 4 of 162.5 Legal Considerations
2.5.1 The tree is protected as T10 of Tree Preservation Order 1437/2012. You are required to apply for
permission from Wokingham Borough Council under the TPO Legislation prior to carrying out any work to
the trees.
2.5.2 The consent of the LPA is not required in order to remove deadwood from a living tree under the TPO
Legislation, however I would recommend that you give the LPA 5 days’ notice in writing.
2.5.3 Emergency work or work to a dead or dangerous protected tree is also exempt under the TPO Legislation
however, you are required to give the LPA 5 days’ notice where possible before carrying out the work or
immediately after the work where a tree was considered imminently hazardous.
2.6 Protected Species
2.6.1 All birds, their nests and eggs are protected under UK law by the Wildlife and Countryside Act 1981. In
Britain all bats are protected under European law (HM Government Habitat and Species Regulations
2010). Bats and birds can use cracks and cavities in old trees to nest, roost and hibernate.
2.6.2 Prior to instructing or carrying out works to trees, you must ensure your chosen contractor is aware of
the legislation and that protected species are not harmed or disturbed during the course of any tree
work.
2.7 ‘Veteran’ Definition
2.7.1 The term veteran tree is one that is not capable of precise definition but it encompasses trees defined by
three guiding principles:
Trees of interest biologically, aesthetically or culturally because of their age;
Trees in the ancient stage of their life
Trees that are old relative to others of the same species.
2.7.2 A veteran tree can be defined as ‘a tree that is of interest biologically, culturally or aesthetically because
of its age, size or condition1. The Oak within the Matthews Green School Site has many defects and
features that mean it is has value to local biodiversity.
2.7.3 Appropriate management of the tree will safeguard the genetic resource of the tree and keep individual
trees within the North Wokingham SDL alive for as long as possible enabling new trees to establish to
replace the old ones. Retained, the tree will enhance the amenity of the site retaining a landscape
feature within the new development which references back to history and previous landscape before
development and a valuable educational resource for the school.
2.7.4 Veteran trees are vulnerable to damage through various means in particular compaction, bark damage,
pollution and premature removal to address risk to persons or property. This tree has been damaged in
the past large wound on the lower trunk and branches above which is commensurate with fire damage.
1
READ, H., February 2000. Veteran Trees, a guide to good management, (13) English Nature
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2027
REF. SCD 04048/2017
FEBRUARY 2017 Page 5 of 162.7.5 Consequently the tree has been colonised be several species of fungi including Ganoderma resinaceum,
Meripilus giganteus and Fistulina hepatica. The work of these fungal species increase the variety of
habitat for the local insect population but these species also undermine the structural integrity of the
tree.
2.7.6 Excessive pruning of the tree can cause a marked loss of vitality in the tree and cause the tree to go into a
state of terminal decline.
2.7.7 This report identifies the initial management requirements of the tree and appropriate levels of access
and occupation of the rooting area around the base of the tree once the school open.
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2027
REF. SCD 04048/2017
FEBRUARY 2017 Page 6 of 163 TREE MANAGEMENT STRATEGY
The Aim of this Strategy is:
To increase the potential life expectancy of the veteran tree by
i) preventing catastrophic failure of weakened branch union and
ii) by protecting and enhancing the rooting area of the tree
so that it can be reasonably retained for the foreseeable future without unacceptable risk to users of the
school site, as an important landscape feature; educational resource and in order to maintain and
enhance the biodiversity of the developed site with the retention of deadwood and other such features
which make veteran trees of particular conservational value.
3.1 Essential Tree Work Operations.
3.1.1 The primary reason for working on a Veteran tree is to prolong its life. The tree has many areas of
structural weakness which are often considered defects2. Those of particular note which could potentially
cause the catastrophic failure of all or part of the tree are the large wound at the base of the tree and the
active crack between the branch union from 2.5-5m above ground level.
3.1.2 As a general rule veteran oak trees respond to cutting more positively than some other species but older
trees do not respond nearly as well as young ones. Although success can be obtained following total
removal of the crown, the chance of regrowth is significantly higher when branches are retained and on
most sites it is essential. It has proved beneficial in some cases to cut the tree in stages, first doing some
initial crown reduction work and then coming back a few years later to reduce further. Oak regrowth is
susceptible to mildew and this may be severe enough to affect the survival of the tree. Defoliating
caterpillars may also have a detrimental effect.
3.1.3 A substantial but phased reduction of the tree is proposed in order to:
Reduce the end weight of branches on the weak branch union.
Reduce the sail of the canopy of the tree in high wind.
Promote the natural retrenchment of the canopy which has already begun naturally with the
growth of mature epicormic growth on the lower 5m of trunk.
Keep the potential ‘fall area’ in the event of a catastrophic fail of all or part of the tree within the
controlled access zone to be located around the base of the tree.
3.1.4 The strong lower epicormic growth will improve the tree’s response to major pruning works and any
smaller twigs and branches below the reduction point will be retained.
3.1.5 Deadwood will be retained within the tree where it is safe and reasonable to do so.
3.1.6 The tree will be reduced in 2 stages in accordance with industry good practice 3. In the first stage, prior to
the occupation of the school, the upper branches will be reduced by approximately 2-4m. An appropriate
pruning point will be identified on each branch individually without being unduly influenced by any
2 These ‘defects’ and areas of decay and dysfunction which increase the value of Veteran trees to native
wildlife as habitat and for foraging for food.
3
READ, H.J.(ed.) 1999. Veteran Trees a Guide to Good Management. English Nature
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2027
REF. SCD 04048/2017
FEBRUARY 2017 Page 7 of 16aesthetic need for symmetry balance. A high proportion of the lower canopy and all stem and epicormics
shoots will be retained intact.
3.1.7 After an interval of 3-5 years, once the lower canopy has had time to thicken a second cut will be
undertaken where appropriate to bring the crown down to an appropriate lower level retaining the new
growth produced lower in the canopy as a result of the first cut. This cut would look to create a new height
of around 9-11m but which would ultimately be decided once the response and recovery of the tree to the
first cut has been appraised.
1. Before 1st cut 2. After 1st cut 3. Before 2nd cut 4. After 2nd cut
Indicative diagrams demonstrating the benefit of cutting a Veteran tree in two stages 4.
3.1.8 Previous consultants who have assessed the tree have discussed a reduction to be undertaken over a 20
year period. My professional opinion is that condition of the tree and decay evident within the high risk
school site means that this timescale is not practical. The 3-5 year timescale for the second reduction is in
accordance with the 1-5 year guidelines for the second cut given in ‘Veteran Trees, A Guide to Good
Management’ by H Read.
3.1.9 Non-invasive cable bracing is not proposed at this time as it felt that the decay and dysfunction on the
western half of the split fork undermines the remaining residual wood to such an extent that it would not
be able to support cable bracing at this time. This can be reviewed at a later date following the initial
canopy reductions if appropriate.
3.2 Phenology
3.2.1 Pruning work will be scheduled to respect the physiological cycle of the tree. The initial reduction of the
canopy will be undertaken in July / August 2017 outside of any severe drought period.
3.2.2 Further cutting will be scheduled during the winter months and the period of dormancy so as to reduce the
potential disturbance to nesting birds.
3.2.3 At no point will any non-urgent tree work be undertaken in the period immediately before or after leaf
break March-May when the trees energy reserves are at their lowest or Autumn September – November
when fungal spores are most prevalent.
4 Diagrams from READ, H.J.(ed.) 1999. Veteran Trees a Guide to Good Management. English Nature
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2027
REF. SCD 04048/2017
FEBRUARY 2017 Page 8 of 163.3 Standards of work
3.3.1 Where possible tree work will be undertake in accordance with BS:3998 2010 ‘Tree Work
Recommendations’. Often when carrying out work to veteran trees the exceptional circumstances may
mean going beyond the guidelines and recommendations within the BS: 3998. In such circumstances
reference should be made to industry best practice and guidelines given in the English Nature publication
‘Veteran Trees, A Guide to Good Management’ by Helen Read.
3.3.2 In all cases the least pruning necessary to preserve the tree is appropriate. Where and what is pruned will
be guided by the need to preserve the tree rather than aesthetics and appearance of the result.
3.3.3 Work to Veteran Trees should be well planned well in advance. If the tree responded poorly to previous
cuts then further work scheduled to the tree will need to be reconsidered.
3.4 Monitoring
3.4.1 Due to the high risk nature of the school site the tree should continue to be visually inspected by a
competent Arboriculturist every 8-14 months planned in order to vary the season of the inspection.
3.4.2 A more detailed inspection (Level 3) which will include a climbing inspection and assessment of wood using
a Picus Tomograph or similar is also appropriate every 3-5 years to monitor the spread of decay within the
trunk (although the exact timing of this will be guided by the findings of the Level 2 annual visual tree
inspection.
3.4.3 The management of Veteran Trees will require consistency and a long term vision. Photographic records
should be kept of the tree and in particular to compare the response and condition of the tree following
pruning works. Any changes to the tree which are noted between the scheduled inspections should be
photographed and forwarded to a designated Arboriculturist (which may include the Borough Council’s
Tree Officers once the School is occupied) for assessment and further inspection where necessary.
3.5 Surrounding Land Use
3.5.1 Much of the success in retaining the tree within the school grounds will be dependent on managing the risk
to pupils and others who can reasonably be expected to be within the target zone of the tree as well as
preventing damage through compaction or development within the trees rooting area which could cause
the tree to go into terminal decline.
3.5.2 It is proposed that the area beneath the current canopy of the tree be fenced off to create a habitat area.
3.5.3 Controlled access of the site can be permitted for educational purposes however the boundary fence and
closed gate is intended to be of a reasonable height so as to prevent inadvertent access of pupils or the
creation of desire lines which could occur across a lower barrier where pupils cut through from the carpark
to the playing fields.
3.5.4 Information boards and plaques recording the significance of the tree or the wildlife within it are
encouraged however they will need to be located outside of the controlled access area allowing visitors to
appreciate the benefits of the tree from a distance.
3.5.5 Seating should not be installed within the controlled access area around the base of the tree.
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2027
REF. SCD 04048/2017
FEBRUARY 2017 Page 9 of 163.6 Protection of Tree Roots (Post Development)
3.6.1 The tree’s roots are expected to be located in the top 60cm of soil and can extend over 30m from the tree.
Areas around the base of the tree have already been subject to compaction. In my professional experience,
mechanical means of redressing compaction such as an ‘Airspade’ or Terra vent’ system have unreliable
success on heavy clay soils and can cause damage to fine feeder roots.
3.6.2 Therefore in order to address the compaction of the rooting area holes a minimum of 75 to 100mm deep,
should be punched in the ground using a with a garden fork. The holes will be about 25-50mm apart,
concentrating in the areas to the north west of the trees rooting area which are holding surface water.
3.6.3 There should be no fires within 15m of the tree.
3.6.4 Although it is acceptable not to collect grass clippings or leaves in the controlled access area, large
quantities of garden waste, leaf mulch and grass clippings must not be stored, mounded or composted
within the controlled access area around the base of the tree.
3.6.5 Chemicals shall not be stored or applied within 15m of the tree this includes weed killers and grass
enhancers such as lawn ‘weed and feed’.
3.7 New Planting
3.7.1 The optimum ground coverage for the tree would be a well-rotted Oak Mulch applied 5-10cm thick around
the base of the tree and topped up when appropriate. This would also require regular weeding and
maintenance within the school site. As such it may not be a practical and reasonable long term solution for
the school.
3.7.2 I am therefore proposing that the grass area around the tree is retained and following a light scarification
will be over seeded with a wild flower seed mix (specifically mixed and prepared for clay soils) as per the
supplier’s instructions. The grass and flower mix should be allowed to grow long and will be cut short once
a year in the Autumn.
3.7.3 The addition of a low level native hedgerow around the boundary of the square would increase the shelter,
habitat and foraging opportunity within the site whilst enhancing the amenity of the area.
3.8 Further Enhancement of biodiversity
3.8.1 In order to improve the biodiversity of the area as well as educational interest, bat boxes and nesting boxes
are encouraged.
3.8.2 Deadwood which falls from the tree should be stacked and left on site. If it can be coordinated, it would
also be highly beneficial for some pieces of large timber from other trees within the wider development
site which have been recently felled or fallen to be moved into this location to diversify the habitats on site
(provided the consent of the timber owner is acquired).
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2027
REF. SCD 04048/2017
FEBRUARY 2017 Page 10 of 164 APPENDICES
A. Tree Inspection
B. Inspection Notes
C. Schedule of tree work
D. 10 Year Management Plan
E. Proposed Site Layout – post development.
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2027
REF. SCD 04048/2017
FEBRUARY 2017 Page 11 of 16A TREE INSPECTION
Inspection information
The weather was dry and visibility considered to be good. Non-invasive inspection equipment (mallet and
metal probe) were used to make an assessment of the structural integrity at the base and trunk of the trees.
The Inspection undertaken was a ‘Level 2’ Basic Tree Assessment. This is defined as a detailed visual
inspection of the trees and surrounding site, and a synthesis of the information collected.
The Inspection methodology followed the visual tree assessment (VTA) methodology prescribed by Mattheck
and Breloer (1994).
For the purposes of this survey all dimensions of trees and their associated parts are measured using a laser
measure, girth tape or clinometer where possible. Where access is restricted measurements have been
visually estimated unless otherwise stated.
Caveats
Trees are dynamic living organisms subject to change, whose health and condition can be subject to
significant change influenced by internal and external factors. The assessment, conclusions and
recommendations from the report are based on the condition of the tree assessed at the time of inspection
and are valid for 18 months.
A tree inspection takes into consideration predictable seasonal variation of weather but cannot predict the
response of the trees in the event of unpredictable (extreme) weather conditions. If the condition of the trees
evidently changes or the trees are subject to extreme weather conditions before this date; further inspection
may be required.
No tree is ever absolutely safe due to the unpredictable laws and forces of nature.
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2027
REF. SCD 04048/2017
FEBRUARY 2017 Page 12 of 16B INSPECTION NOTES
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2022
REF. SCD 04048/2017
FEBRUARY 2017 Page 13 of 16C TREE WORK SCHEDULE
This tree work schedule is to be read and followed in conjunction with the information and advice given in the
Veteran Tree Management Schedule ref. 04048/2017.
All work is subject to necessary TPO consents.
July / August 2017 Selectively reduce extended branches by 2-4m using suitable reduction points
taking care not to damage epicormics shots and foliage below these points.
December / January 2020 - 2012 Undertake a further reduction of main branch network of approximately 2-3m
taking care not to damage epicormics shots foliage and new growth below
these points.
Indicative pruning cut locations – The final location of pruning cuts will be decided by the competent tree surgeon to
ensure the best possible outcome for the tree.
Red Line – Year 1 cuts (July – August 2017)
Yellow Line – Suggested second reduction (Year 3-5 dependent on recovery and most recent inspection)
Green Line – Indicative canopy outline to be achieved
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2022
REF. SCD 04048/2017
FEBRUARY 2017 Page 14 of 16D TEN YEAR MANAGEMENT PLAN
Spring
Summer
Autumn
Winter
Not season dependent
Task Year
1 2 3 4 5 6 7 8 9 10
First Reduction of canopy X
Install boundary fencing (on completion of build) X
Plant bare root boundary hedging (on completion of
X
build)
Cut hedge outside of bird nesting season (March-
X X X X
September)
Decompact soil areas (on completion of build) X X X
Apply well-rotted Oak mulch to waterlogged areas. X X X X
Scarify grass X X X X
Seed with clay native flower mix X X X X
Install information boards (on completion of build) X
One flower meadow / grass cut X X X X X X X X X
Second reduction of canopy (subject to response to first
tbc tbc tbc
cut)
Level 2 Arboricultural Inspection X X X X X X X X X
Level 3 Detailed inspection of defects with assessment of
X X X
internal wood and decay
Install nesting boxes / bat roots X
Maintain nesting boxes X X X
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2022
REF. SCD 04048/2017
FEBRUARY 2017 Page 15 of 16E PROPOSED LAYOUT (POST DEVELOPMENT)
Indicative layout of site on completion of the school site.
Matthews Green Primary School – Veteran Oak Management Scheme 2017 - 2022
REF. SCD 04048/2017
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