Tree Safety & Condition Survey at a hospital in London

Transcription

1 Tree Safety & Condition Survey at a hospital in London Dr. Richard Wilson, PhD, Tech. Cert. (RFS), Prof. Dip. Arb (RFS), M. Arbor A., Associate member of the Institute of Chartered Foresters Arboricultural company Instruction: Following an instruction from xxx, I have conducted an arboricultural survey of the trees at xxx. The client requires a visual assessment of tree health & safety. The initial enquiry was received by on November 11 th, An instruction to proceed was received by phone on November 23 rd, Inspection took place on January 13 th, Regulatory work: This survey has been carried out according to HSE SIM 01/2007/05 (HSE, 2007) & Common sense risk management of trees (Forestry Commission, 2011). Techniques: Visual Tree (VTA; Lonsdale, 1999), desk-based enquiries (TPO / CA status, geological survey, mapping), analysis (Forbes-Laird, 2010). Limitations: 1. The contents are intended for the sole use of the client. It is also understood that the document will be shared with his insurers. No liability is accepted for their use by any other parties to advance an argument or claim (including legal or financial) without prior consent. 2. No liability is accepted for defects hidden from view by soil, vegetation or other obstacles to access. 3. Formal assessment of topography, drainage, service conduits, & soil conditions have not been made and are beyond the scope of this report. 4. Specific laboratory investigations of soil properties (plasticity index, moisture content, soil suction pressure) have not been made and are beyond the scope of this report. 5. This report considers only the potential for the tree to cause damage or injury under normally expected weather conditions. No liability for damage arising from any other source or mechanism is accepted. 6. This report will be deemed to be invalid if a history of vegetation related subsidence damage in this or surrounding properties exists but has not been made known to the surveyor. 7. This report considers risk mitigation measures, as opposed to risk elimination. Thus, if the tree is retained, a level of risk will remain. 8. It is understood that any risks associated with these limitations are accepted by the clients. Weather conditions: Hazy sunshine with cloud, wind force 2. Access conditions: Access was generally unhindered but several trees were obscured by dense ivy and scrub undergrowth. Validity: Plants are biological organisms & change with time. remains valid for 12 months from the date of, or until a major storm (Wind Force 6 +) is experienced. Background information: The results of an earlier survey conducted in Feb 2014 by xxx were made available. Situation: The hospital stands at an elevation of 60m in a Central London urban setting to the south of the River Thames (OS Maps 2016). Surface deposits are clays & silts of the London Clay Formation (BGS 2016). Soil type is described as a slowly permeable, seasonally wet, slightly acid but base-rich clay loam of moderate fertility and impeded drainage (LandIS 2016). The site therefore has slightly raised wind exposure, complex (non-laminar) windflows and is prone to waterlogging. References: British Geological Survey (2016). Geology of Britain Viewer 1:50,000. BGS, Keyworth, Nottingham. British Standards Institute (2010). BS3998:2010 Standards for Tree Work. BSI Publications, London. Forbes-Laird, J. (2010). tree hazard assessment system. LandIS (Land information system; Soilscape viewer). Cranfield University. Lonsdale, D. (1999). Principles of Tree Hazard and Management. The Stationery Office, London. Ordnance Survey (2016). OS Maps service at Ordnance Survey, Southampton. 25/01/2016 Cover sheet

2 Page 1 Health Structure 301 Norway maple Acer platanoides Young 10 Good Minor deadwood 5 Repeat 30% crown reduction Cherry Prunus kanzan Young 8 Good Single crossing limb 5 Repeat 30% crown reduction; remove crossing limb Hawthorn Crataegus monogyna mature 8 Good Included bark unions 5 Repeat 30% crown reduction Oak Quercus robur Veteran 13 Low vigour but as expected for a tree of this age Old pollard with primary & secondary pollard points. Managed with reduction and bracing in past. Bracing ineffective. Extensive hollowing and decay cavities in stem and primary limbs; cracks in main stem. 3 Very High % crown reduction from MEWP. Install wooden props to support main limbs Leave existing braces in situ. 1 6 Veteran tree of very high historical and ecological value (approx 300 years old). Trees of this type are a nationally scarce resource and should be conserved whereever possible. 308 Whitebeam Sorbus aria Lutescens Young 7 Good None 5 None Cherry Prunus sp Young 6 Poor. Bark exudates indicating bacterial infection. Ganoderma fungus bracket. Poor. Lower stem decayed Remove Two included bark unions, one girdled limb in crown top, deadwood, long lateral 310 Weeping willow Salix sepulcralis chrysocoma Young 13 Good striking fence 3 Moderate Semi-pollard & deadwood fibre-buckling development in central 311 English oak Quercus robur Mature 18 Good stem 3 High Reduce central stem by 2-3m to appropriate growth point Picus scan 312 Sessile oak Quercus petrea Mature 19 Good Good 3 High None 24 Reduce spread of infection by: 1. Remedy early; 2. Sterilise tools; 3. Avoid use of chipper 313 Cherry Prunus avium Young 5 Good Good 4 None Pissard's plum Prunus cerasifera 'Pissardii' mature 7 Good Good 5 None 12 Area of reaction wood on stem - monitor 315 Aspen Populus tremula Young 12 Good Good 5 None Aspen Populus tremula Young 12 Good Good 5 None Small leaved lime Tilia cordata Young 12 Good Lean to NW 7. Waterlogged soil 4 Moderate Reduce crown by 30% Birch Betula pendula Young 12 Bacterial wetwood Good 4 None 12 Monitor 319 Broad leaved lime Tilia platyphyllos Young 12 Good development of included bark union 4 Moderate Reduce height by 3m Aspen Populus tremula Young 13 Good Good 4 None Hawthorn Crataegus monogyna mature 8 Good Good 4 None Aspen Populus tremula mature 19 Good Unbalanced crown. Waterlogged soil. 4 Reduce height by 4m Norway maple Acer platanoides Young 12 Good Good 5 None 24 Extensive bark loss / areas of bark Significant deadwood. Hollow sounds over 325 Weeping willow Salix sepulcralis chrysocoma Mature 13 dysfunction most of stem circumference 4 Moderate Pollard Plum Prunus domestica Young 9 Good Good 5 None Blue atlas cedar Cedrus atlantica 'Glauca' Young 10 Good Good 4 None Red horse chestnut Aesulus x carnea Young 9 Good Good 5 None Leyland cypress X Cupressocyparis leylandii mature 10 Poor. Seridium cardinale infection Fair. Dead and diseased limbs 5 Low Remove & replace Leyland cypress X Cupressocyparis leylandii Young 10 Good Good 4 Low None Variegated Norway maple Acer platanoides 'Drummondii' Young 9 Fair. signs of bacterial infection. Good 4 None 12 Monitor Copyright WTS 25/01/ of 6

3 Page 2 Health Structure 334 Black cherry plum Prunus cerasifera 'Nigra' Young 6 Good Tight forks and congested crown 4 Reduce crown by 30% Whitebeam Sorbus aria Lutescens Young 8 Good included bark union development 4 Reduce length of bough facing road by 1.5m Broad leaved lime Tilia platyphyllos Young 12 Good Co-dominant stems with included bark in fork 4 Remove central stem & reduce limbs by 2m Red oak Quercus rubra Young 13 Good Good 4 None Broad leaved lime Tilia platyphyllos Young 13 Good 339 Weeping willow Salix sepulcralis chrysocoma Mature 14 Good Tree formed from regrowth on old stump - decay visible in base of all stems 4 Reduce height by 3m Hollow sounds obtained around most of circumference. Crack, deadwood Pollard Copper beech Fagus sylvatica purpurea Young 13 Moderate Good 5 None Indian bean tree Catalpa bignonioides Young 9 Good Site of limb loss noted. Damaged limb 5 Remove damaged limb Sycamore Acer pseudoplatanus Young 8 Good Squirrel damage, minor deadwood 5 Remove deadwood and damaged branches Bullace Prunus insititia Young 7 Good Fair - tight forks 5 Selective branch removal to alleviate tight forks Holm oak Quercus ilex Young 8 Holm oak leaf miner infestation (Phyllonorycter messaniella) Good 5 None Leyland cypress X Cupressocyparis leylandii Young 10 Good Good 5 None Cherry Prunus kanzan mature 7 Good Good 4 None Crab apple Malus sylvestris mature 7 Good Good 5 None Western red cedar Thuja plicata Young 8 Good Good 5 None English oak Quercus robur Mature 18 Good Minor deadwood throughout tree. Encroaching on streetlamp. Hollow sounds obtained. 3 Remove deadwood. Crown lift to 4m. Prune to clear streetlamp by 1m Picus scan 351 Turkey oak Quercus cerris mature 16 Good Moderately unbalanced crown 3 Reduce height by 4m b Cheesewood Pittosporum sp. mature 8 Good Good 5 None Holm oak Quercus ilex Young 8 Holm oak leaf miner infestation (Phyllonorycter messaniella) Good 5 Sever ivy Holm oak Quercus ilex Young 9 Holm oak leaf miner infestation (Phyllonorycter messaniella) Good 5 Sever ivy Lean towards overhead wire by 28. Hanging Remove hanging limb. Reduce 354 Sycamore Acer pseudoplatanus Young 8 Good deadwood height by 2m English oak Quercus robur mature 12 Good Minor deadwood 4 Remove deadwood Grey Sallow Salix cinerea mature 8 Moderate Hollow and leaning towards church Pollard Holly Ilex aquifolium mature 9 Moderate Wound on stem at 2m 5 None Holly Ilex aquifolium mature 10 Moderate Good 5 Cut back from boundary Yew Taxus baccata mature 11 Poor - stressed Good 5 Aerate soil, feed with Fish, Blood & Bone, apply woodchip mulch Lawson's cypress Chamaecyparis lawsoniana Young 8 Good Sparse crown. Seridium infection. 5 None 12 Monitor 361 Holly Ilex aquifolium Young 7 Moderate Good 5 None 24 Low risk management priority but tree would benefit if carried out this spring Copyright WTS 25/01/ of 6

4 Page 3 Health Structure 362 Wild cherry Prunus avium Young 8 Moderate Leaning by 15 5 None 12 Monitor 363 Common lime Tilia x europea 364 Holly Ilex aquifolium Major decay at 10m. Large burr at base suggesting stress. Stem significantly narrowed at base. Significant deadwood Aerial insopection, remove deadwood and reduce height by 4m mature 19 Good mature 8 Moderate Good 5 None Sycamore Acer pseudoplatanus Young 10 Moderate Squirrel damage, minor deadwood 5 Remove deadwood a + b Holly Ilex aquifolium Young 5 Moderate Good 4 None Italian cypress Cupressus semervirens Young 8 Good Good Plum Prunus domestica mature 4 Moderate Good 5 24 Remove three stems to relieve compression at base pls one 369 Common lime Tilia x europea mature 18 Good Overstood coppice. Multiple included bark unions and hollows at base. Some significant deadwood stem leaning towards building. Reduce height remaining stems by 5m. Remove deadwood Poor - black exudates on stem suggesting 370 English oak Quercus robur mature 12 Acute Oak Decline Good 4 None 12 Monitor 371 Yew Taxus baccata mature 4 Good Weak branch attachment at 4m 4 None 24 Prune away from overhead 372 False acacia Robinia pseudoacacia Young 11 Good Only SW stem remains (NE stem removed) 4 wire Leyland cypress X Cupressocyparis leylandii mature 15 Good Good 3 Crown lift over road and wire False acacia Robinia pseudoacacia Young 11 Moderate Good 5 None Bay laurel Laurus nobilis mature 6 Good Good 3 None Highclere Holly Ilex altaclarensis variegatum Young 8 Moderate Good 4 None Highclere Holly Ilex altaclarensis variegatum mature 9 Moderate Good 4 None False acacia Robinia pseudoacacia mature 13 Good Minor deadwood 3 None Bay laurel Laurus nobilis mature 6 Good Minor deadwood 3 None Highclere Holly Ilex altaclarensis mature 5 Poor Good 3 None Box-leaf azara Azara microphylla mature 4 Moderate Cavities at base. Areas of bark loss extedning up branches 3 Prune away from building. Remove single small decayed limb to N Sycamore Acer pseudoplatanus mature 18 Good Crown unbalanced - nearby tree recently removed. Pruning wound at base to NW with some decay. Hanging limb at 8m. 2 Remove hanging limb Picus scan 384 Wild cherry Prunus avium Young 6 Moderate Good 5 None Wild cherry Prunus avium Young 7 Good Good 4 None Wild cherry Prunus avium Young 6 Poor Good 5 None Whitebeam Srbus aria 'Lutescens' mature 8 Good Good 4 None 24 Copyright WTS 25/01/ of 6

5 Page 4 Health Structure 388 Wild cherry Prunus avium Young 6 Good Good 5 None Wild cherry Prunus avium Young 6 Moderate Good 5 None Wild cherry Prunus avium Young 6 Good Good 5 None False acacia Robinia pseudoacacia mature 15 Good Good 2 None 24 G1 Leyland cypress X Cupressocyparis leylandii Mature 8 Row sporadically infected with Seridium. Occaisional large branches failing. 4 Prune out infected limbs G2 Leyland cypress X Cupressocyparis leylandii Mature 7 Light infection with Seridium Occaisional branch failure 4 Prune out infected limbs G303 Sumach Rhus typhina Mature 5 Generally poor condition with deadwood. Overlong limbs 4 Prune to new lower profile over several years by sequential pruning of stems and allowing regrowth to establish before pruning next stem G4 Cherry Prunus sp. Young 6 Good but group overcrowded Good 4 Thin plants by 30% N1 Aspen Populus tremula Young 13 Good Good 5 None 24 N2 Lawson's cypress Chamaecyparis lawsoniana Young 9 Moderate Good 5 None 24 Holm oak leaf miner infestation N3 Holm oak Quercus ilex Young 8 (Phyllonorycter messaniella) Good 5 None 24 N4 Apple Malus domestica Young 3 Good Good 5 None 24 N5 Apple Malus domestica Young 3 Good Good 5 None 24 N6 Apple Malus domestica Young 3 Good Good 5 None 24 N7 Apple Malus domestica Young 3 Good Good 5 None 24 N8 Apple Malus domestica Young 5 Bark dysfuncton on NE limb Good 5 Remove NE limb N9 Apple Malus domestica Young 5 Good Good 5 Formative pruning N10 Hazel Corylus avellana mature 5 Good Good 5 Thin coppice growth N11 Box elder Acer negundo Mature 4 Good Good 5 None 24 N12 Hazel Corylus avellana Mature 6 Good Good 5 Thin coppice growth N13 Hazel Corylus avellana Mature 6 Good Good 5 Thin coppice growth P1 Cherry Prunus avium plena Young 5 Good Good 4 None 24 P2 Silver birch Betula pendula Young 7 Good Good 4 None 24 P3 Cherry Prunus amagawa Young 5 Moderate Good 4 P4 Cherry Prunus amagawa Young 4 Moderate Good 4 P6 Cherry Prunus amagawa Young 8 Good Good 4 None 24 P7 Cherry Prunus amagawa Young 6 Good Good 4 None 24 Copyright WTS 25/01/ of 6

6 Page 5 Health Structure P8 Cherry Prunus amagawa Young 4 Moderate Good 4 P10 Magnolia Magnolia soulangiana Young 4 Poor Good 4 None 24 P12 Cherry Prunus padus Young 5 Good Good 4 None 24 P13 Cherry Prunus kanzan Young 6 Good Good 4 None 24 P14 Cherry Prunus sp Young 3 Good Good 4 None 24 P15 Black cherry plum Prunus cerasifera nigra Young 6 Good Good 4 None 24 P16 Cherry Pruns serrulata Young 5 Good Good 3 None 24 P17 Cherry Prunus subhirtella Young 4 Good Good 3 None 24 P18 Silver birch Betula pendula 'Youngii' Young 2 Poor Good 4 P19 Cherry Prunus sp Young 3 Moderate Good 4 P20 Golden chain Laburnum anagyroides Young 3 Moderate Good 4 P21 Black cherry plum Prunus cerasifera nigra Young 4 Good Good 4 None 24 P22 Almond Prunus dulcis Young 5 Moderate Good 4 P23 Norway maple Acer platanoides 'Drummondii' Young 4 Good Good 5 None 24 P24 Silver birch Betula pendula Young 6 Good Good 4 None 24 P25 Silver birch Betula pendula Young 7 Good Good 4 None 24 P26 Silver birch Betula pendula Young 6 Moderate Good 4 P27 Silver birch Betula pendula Young 6 Good Good 4 None 24 P28 Silver birch Betula pendula Young 7 Good Good 4 None 24 P29 Silver birch Betula pendula Young 7 Good Good 4 None 24 P30 Silver birch Betula pendula Young 7 Poor Good 4 P31 Silver birch Betula pendula Young 6 Good Good 4 None 24 P32 Silver birch Betula pendula Young 5 Poor Good 4 P33 Rowan Sorbus aucuparia Young 8 Good Good 4 None 24 P34 Rowan Sorbus aucuparia Young 6 Good Good 4 None 24 P35 Rowan Sorbus aucuparia Young 8 Good Good 4 None 24 P36 Rowan Sorbus aucuparia Young 6 Good Good 4 None 24 P37 Turkish hazel Corylus colurna Young 6 Good Good 4 None 24 P38 Turkish hazel Corylus colurna Young 5 Good Good 4 None 24 P39 Turkish hazel Corylus colurna Young 6 Good Good 4 None 24 Copyright WTS 25/01/ of 6

7 Page 6 Health Structure P40 Magnolia Magnolia soulangiana Young 6 Good Good 4 None 24 P41 Magnolia Magnolia soulangiana Young 6 Good Good 4 None 24 P42 Magnolia Magnolia soulangiana Young 5 Declining Good 4 P43 Magnolia Magnolia soulangiana Young 6 Good Good 4 None 24 P45 Autumn cherry Prunus subhirtella Young 3 Good Good 4 None 24 P49 Sweet Gum Liquidambar styraciflua Young 3 Stressed Good 6 P50 Magnolia Magnolia soulangiana Young 5 Good Good 5 None 24 P51 Magnolia Magnolia soulangiana Young 5 Declining Good 5 P52 Magnolia Magnolia soulangiana Young 5 Good Good 5 None 24 P53 Turkish hazel Corylus colurna Young 6 Good Good 4 None 24 P54 Turkish hazel Corylus colurna Young 6 Good Good 4 None 24 P55 Turkish hazel Corylus colurna Young 8 Good Good 4 None 24 P56 Rowan Sorbus aucuparia Young 8 Good Good 4 None 24 P57 Rowan Sorbus aucuparia Young 8 Good Good 4 None 24 Tree Numbering: Trees identified by individual tags are listed according to their tag numbers Trees not tagged are prefixed with the letter 'N' New plantings (less than five years in situ) are prefixed with the letter 'P 'Groups are prefixed with the letter 'G' General Risk Zone 1. Primary transport infrastructure / utility wayleaves / high or constant occupancy facilities 2. Secondary transport infrastructure / moderate or daytime occupancy facilities 3. Peak time transport route / occaisional occupancy facilities 4. Occaisional transport route / largely unoccupied facilities or structures 5. Rural rights of way / ground structures 6. Remote paths / grass Work time: SD - self determined 24-2 years 12-1 year 6-6 months 1-1 month 7D - 7 days E - emergency Inspection time: IRecommendations assume manual work specified is carried out within the time indicated years 12-1 year 6-6 months Copyright WTS 25/01/ of 6

8 G303 P1 P2 P3 P4 P6 P7 P8 P10 P G1 313 P12 P13 P14 P15 P16 P P18 P19 P20 P21 P P P P53 P54P55 P56 P33 P34 P35 P36 P37 P39 P P40 P41 P P G4

9 P50 P b N P N N13 N N N7 N5 345 N N N11 351b 351 N9 350 N8 G2 349 N2