P002.1(4) Tree Asset Management and Ash Dieback Disease
North Lanarkshire Council · 24 August 2022
Back to Environment and Place Committee — 24 August 2022 and its agenda
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North Lanarkshire Council Report Environment and Place Committee Does this report require to be approved? ☒ Yes ☐ No Ref NP/VA/HA Date 24/08/22 P002.1(4) Tree Asset Management & Ash Dieback Disease From Nicole Paterson, Head of Environmental Assets E-mail abernethyv@northlan.gov.uk Telephone 07939 280221 1 Ash Dieback Toolkit for Scotland - The Tree Council Executive Summary Inspections which have taken place over the last 12 months are consolidating our understanding of the risks that are present in the Environmental Assets tree stock and the level of remediation work required to reduce those risks to a tolerable level in line with the strategy. The strategy currently only covers trees within council ownership, which are managed and maintained by Environmental Assets, and council owned trees adjacent to the Highway and Schools. Other assets not covered include Housing properties e.g. garden grounds of Council tenants or sites leased to private businesses. As highlighted in an earlier report to the Environment and Transportation committee (August 2021) these areas will also have trees with associated risk that continue to remain unmanaged. This update report also seeks to highlight the known impacts of Ash Dieback Disease, which are fast becoming evident within North Lanarkshire as inspections of our tree assets continue and looks for support to establish an Ash Dieback Action Plan to begin to tackle the corporate risk that is associated in not remediating these trees appropriately. The report also sets out the developing plans around replacement planting to mitigate against the change in the landscape and loss of what will be a considerable quantity of trees over the course of the next 5-10 years. Recommendations It is recommended that the Environment and Place Committee: 1. Approve the approach to tackling Ash Dieback Disease in North Lanarkshire by initially commissioning a desk-based data investigation exercise to inform an Ash Dieback Action Plan as recommended in the Ash Dieback toolkit for Scotland1. 2. Recognises the significant ongoing resource required to effectively tackle the corporate risk associated with this endemic disease and considers further budget to allow continued remediation in line with the TRAM strategy.
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3. Endorse the progress of the planting of the Climate Emergency wood at Strathclyde Country Park in spring 2022 and the continued work that will take place in autumn 2022 at Calderbank and Palacerigg Country Park. The Plan for North Lanarkshire Priority Improve North Lanarkshire's resource base Ambition statement (17) Ensure we keep our environment clean, safe, and attractive
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1. Background 1.1 Since the last report to the Environment and Transportation committee in August 2021 Environmental Assets has further developed its approach to Tree Risk Management, through the implementation of a Tree Risk Asset Management (TRAM) Strategy. Following formal adoption, and the appointment of an Arboriculture Inspector, tree inspections began in spring 2022 and have been carried out in line with the methodology and approach detailed with the strategy. To date, two wards (15 and 17) have been completed in addition to the 2 wards (12 and 19) inspected as part of the pilot of the strategy. At the time of writing inspections are underway in ward 2, with approximately 50% of that ward completed. Since the last report to the Environment and Transportation Committee, Ash dieback has emerged as a significant issue. Ash is Scotland’s sixth most abundant broadleaved tree species (after birch, oak, sycamore, alder and beech) and Scotland’s fifth most abundant native tree species (after Scots pine, birch, alder and oak). This species was used as one of the predominant species in mixed native planting in grant funded planting schemes in the past and is also a common, familiar roadside tree. 1.2 Council’s across Scotland are taking differing approaches to managing Ash Dieback Disease (ADD), below are some examples, which serve to illustrate the breadth of the issue. 1.3 In autumn 2020, City of Edinburgh Council reviewed all known ash data for the city. In particular, they assessed those ash trees adjacent to the road or on council-owned land which could cause a safety issue if they died or fell on to the road or a public space. They found 6% of their city trees were found to be ash, of which 25% were on council owned land. Ash were present in cemeteries, woodland, greenspaces, schools, adjacent to cycleways and on roadside verges. Early estimates suggest there will be additional budget requirements to manage ADD in Edinburgh. 1.4 In Summer 2020 both Angus and South Lanarkshire Council’s undertook desk top analysis to gather data on ash trees adjacent to the roadside (the road network was prioritised as the land holding most likely to have the highest population of high target ash trees most susceptible to ash dieback). From analysis using Google Streetmap Angus estimated 4,920 ash trees on their road network. Using the same tool (with a different methodology, South Lanarkshire Council have estimated 19,143 ash trees in woodlands and other habitats adjacent to the road network. 1.5 Glasgow City Council have estimated ash make up approximately 12% of the city’s trees and that between £25m and £38m will need to be spent felling 31,500 ash trees. It is predicted 4,500 trees annually will be felled over the next seven years. An estimated 7 figure sum has also been predicted to replace the loss through replanting. 1.6 West Lothian Council carried out initial surveys in 2021 and has already committed £265,000 to the initial survey phase, and a further £500,000 in this financial year as felling operations get under way. The projected costs in West Lothian for 2022/23 to 2025/26 are £4.7 million, with a further £7m, at least from 2026 to 2042. 1.7 A July 2022 briefing from APSE that had approached local authorities across the UK estimated 24% of responding authorities estimate costs of over £10M with a further
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21% citing unknown costs. Many local authorities noted that the costs are likely to be higher than their entire greenspace budget over the period. 86% suggested that additional government funds will be required. 1.8 The same report noted that 52% of responding authorities are developing or have developed Ash dieback plans, suggesting there will be developing best practice to utilise. 1.9 Importantly the report estimated that 112million trees will be lost across the UK at a time when we are trying to increase tree cover, and costs of tree replacement are not included in the costs cited above for Ash removal. 2. Update on TRAM inspections 2.1 In undertaking the pilot study of wards 12; Airdrie South and 19; Motherwell South East & Ravenscraig and now having surveyed a further 2 full wards, (15; Bellshill and 17; Motherwell West and with ward 2; Cumbernauld North being over 50% complete) we have improved our understanding of the numbers of level 2 inspections and the resulting remediations that are required to our tree assets to reduce risk to a tolerable level following initial inspection. 2.2 To date the number of trees found to be in a condition where a level 2 tree inspection was required is 397. Chart 1 shows the breakdown of trees inspected by ward (noting that Cumbernauld North is only 50% complete). Chart 1: Remediation 2.3 Following a level 2 inspection and Quantified Tree Risk Assessment, recommended works are identified by the Arbor Inspector. Remedial works or tree removal in wards 12 and 19 have already been undertaken to reduce risk to a tolerable level as outlined within the TRAM strategy. Some of the minor remedial works were carried out by our own arborists, but the majority were carried out by an external contractor. The total cost of the larger contracted remedial works for these wards was £28,755. 2.4 Remedial work for wards 15, 17 and ward 2 will be undertaken this winter, and with indications that two thirds more felling jobs required there will be a significant increase in cost from the initial known costs for wards 12 and 19. The known costs for remedial works for the pilot wards were for the removal of large, mature trees, which take a Airdrie South 9% Motherwell South & Ravenscraig 22% Motherwell West 15% Bellshill 19% Cumbernauld North 35% Percentage of trees identified for Level 2 inspection by ward
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long time to fell. The remediations for the current inspection programme are in the main for removal of ADD trees. Using an average of £354 per tree removal (estimate from Ash die back Toolkit for Scotland) would suggest a figure of around £78,000 for these three wards, this is likely to be conservative as inspections are not complete. There will be additional costs in these wards in the next 3-7 years as more ash trees succumb to the disease. Progress and resources 2.5 The total area of land that is within the survey area for the TRAM strategy (Environmental Assets portfolio where trees are known to exist) is approximately 6,837ha, to date we have completed 1,653ha (about one quarter). It is set out in the TRAM strategy that the inspector will survey 3-4 wards per year, we are on track to complete 4 wards this year. However, Ash Die Back disease is increasing the numbers of trees requiring a Level 2 inspection, so we anticipate inspection rates to reduce without further resources or a separate action plan for Ash Dieback Disease being introduced and resourced. Ash Dieback Disease 2.6 As the TRAM strategy inspections have progressed, it has been evident that a significant number of ash trees on council assets are showing advanced signs of ash dieback disease (ADD). As part of the TRAM inspections, all ash trees within risk zones exhibiting stage 3 and 4 infections are being recorded in line with Ash dieback: An Action Plan Toolkit for Scotland. Stage 4 is the most advanced stage of the disease and determined by a significant loss of canopy (with only 0%-25% remaining). 2.7 To date approximately 50% of ward 2, Cumbernauld North has been inspected. The total number of trees inspected at level 2 is 137, of which 107 were diseased ash trees at Stage 3 and Stage 4 condition. As a result of the TRAM inspection, all 107 ash trees have been identified for removal. 2.8 An additional budget of £100k has been allocated for FY 22/23 from reserves which will be used to develop an Ash Die Back Action Plan (ADBAP), which will follow The Tree Council’s Ash Dieback: An Action Plan Toolkit for Scotland guidance document. The ADBAP will provide us with a strategic approach to tackling infected trees. In particular it will provide a detailed outline and costings as to how a risk based approach will be implemented as well as a program of prioritisation. The allocated budget will also be used to begin removal of priority infected trees identified as part of the ADAP. Case Study: Westfield 2.9 Council tree assets within risk zones in and around Westfield were surveyed in June. A total number of 86 trees were identified as requiring a level 2 arboricultural inspection and QTRA assessment in line with the TRAM strategy. The location of inspected trees is shown in map 1 below.
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Map 1 Of the total number of trees inspected, 85 trees were identified for removal. Only 10 of the 86 trees were a non-ash species. The 75 ash trees recorded also included some small groups of ash. Where small groups of infected ash were identified they were recorded as 1 record, this brings the total number of ash trees to be removed to approximately 115. In line with general observations relating to the condition of ash throughout the local authority, it was found that the majority of Stage 3 and Stage 4 infected trees were of a young to semi- mature age class. 2.10 Using an average cost of £354 per tree removal, estimated costs for removal of only infected ash trees in Westfield is £40,710. Extrapolating the cost from this sample data, it can be seen that the cost to deliver ash die back removal throughout the rest of the local authority is expected to be extremely significant.
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2.11 A report to the Environment and Transportation committee last August described the loss of 50-75% of Scotland’s ash trees over the next 20 years, from the data that we have so far in North Lanarkshire it would appear that our loss may be seen much sooner, in perhaps 7-10 years, this is based on the small dataset collected so far and the rate at which trees deteriorate is not fully understood in any area of Scotland or indeed the UK. Impact of ADD on TRAM progress 2.12 From the data above, it is apparent that much of the work of the Arbor Inspector is now being dominated by recording data at level 2 inspection on ash trees and this is beginning to slow the progress of inspection – for Westfield above, if ADD trees were being recorded through a separate action plan then the requirement would only have been for 30 trees to be picked up through the TRAM work (in the half of the ward that has been completed to date). This reduction in additional stage 2 inspections (for ADD trees) would allow progress to continue in other wards more quickly and ensure that the estimated progress of 3-4 wards per year can keep the TRAM strategy on schedule. 2.13 To enable ADD mitigation to be resourced would require another inspector post to be created, or to rely on data such as that available (with a cost) through iTree (a tool allowing canopy analysis through aerial photography) which would help to estimate the number of ash trees in NLC ownership and therefore help to understand the cost to reduce the risk of ADD across the authority. 2.14 As highlighted in the report last August, as there is going to be a significant increase in ADD work, we could look to carry out some of this in house, but with current resource this would mean that all non-routine jobs would effectively be put on hold unless additional arborists resource is allocated to focus on remediation of ADD trees. Even with this, there will still be the remediation of trees identified through business as usual TRAM (that are not ADD related) to fund. There is £180,000 of capital funding identified for this until 2025/26, but this was based only on works associated with the TRAM strategy and was not able to predict the additional costs of ADD at that time. 2.15 A further report will be brought to committee detailing the Ash Die back actin plan and estimated costs and implementation options. This report will also highlight the possible implications of the disease in non council owned trees and their impact on NLC assets if the owners do not remediate. Climate Emergency Woods 2.16 To date P7 pupils involved in the Outdoor Education Programme at Strathclyde Country Park have planted over 4500 native trees as part of the Climate Emergency Woods programme, a further site with 2300 trees has been planted up at Low Wood (Cumbernauld). Two further sites in Calderbank and Palacerigg Country Park will be planted in the new planting season from October. Operational Woodland Planning 2.17 Over the next year a long-term operational plan for managing the Council’s woodlands will be developed. This will consider the impact of loss of tree assets as a result of
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more regular inspection and ADD and will provide a scope for longer term replenishment planting (including the consideration of funding opportunities linked to accessible woodlands). The plan will consider the availability of land for future planting and any commitments the Council can make under the Woodland Carbon Code to register our new planting sites for carbon credits in the future. As part of the current review of North Lanarkshire’s Biodiversity Action Plan the Woodland Action Plan will be updated to reflect Ash Dieback Disease and it’s impact on the landscape of our woodlands and wider landscape settings. The plan will work with Clyde Climate Forest to ensure we are contributing to those outcomes. We will also look for opportunities for Carbon accreditation of new planting to inset council carbon emissions that are hardest to reduce. 3. Measures of success 3.1 Increase in the number of trees inspected in line with the Tree Asset Management Strategy. 3.2 An increase in the number of trees remediated following inspection to reduce their risk of failure. 3.3 Delivery of an Ash Dieback Action Plan to guide the significant resource planning required to respond to Ash Die Back disease 3.4 Delivery of an operational woodland plan will provide a future vision of replenishment planting (following large scale felling though TRAM and Ash Dieback work) and wider planting schemes to assist with carbon reduction and improvements to biodiversity. 4. Supporting documentation none Nicole Paterson Head of Environmental Assets
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5. Impacts ( http://connect/report-template-guidance ) 5.1 Public Sector Equality Duty and Fairer Scotland Duty Does the report contain information that has an impact as a result of the Public Sector Equality Duty and/or Fairer Scotland Duty? Yes ☐ No ☒ If Yes, please provide a brief summary of the impact? If Yes, has an assessment been carried out and published on the council’s website? https://www.northlanarkshire.gov.uk/your-community/equalities/equality-and-fairer- scotland-duty-impact-assessments Yes ☐ No ☐ 5.2 Financial impact Does the report contain any financial impacts? Yes ☒ No ☐ If Yes, have all relevant financial impacts have been discussed and agreed with Financial Solutions? Yes ☐ No ☒ If Yes, please provide a brief summary of the impact? £100k allocated from reserves to deliver Ash dieback action plan and initial risk remediation 5.3 HR policy impact Does the report contain any HR policy or procedure impacts? Yes ☐ No ☒ If Yes, have all relevant HR impacts have been discussed and agreed with People and Organisational Development? Yes ☐ No ☐ If Yes, please provide a brief summary of the impact? 5.4 Legal impact Does the report contain any legal impacts (such as general legal matters, statutory considerations (including employment law considerations), or new legislation)? Yes ☐ No ☒ If Yes, have all relevant legal impacts have been discussed and agreed with Legal and Democratic Solutions? Yes ☐ No ☐ If Yes, please provide a brief summary of the impact? 5.5 Data protection impact Does the report / project / practice contain or involve the processing of personal data? Yes ☐ No ☒ If Yes, is the processing of this personal data likely to result in a high risk to the data subject? Yes ☐ No ☐ If Yes, has a Data Protection Impact Assessment (DPIA) been carried out and e- mailed to dataprotection@northlan.gov.uk Yes ☐ No ☐ 5.6 Technology / Digital impact Does the report contain information that has an impact on either technology, digital transformation, service redesign / business change processes, data management, or connectivity / broadband / Wi-Fi?
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Yes ☐ No ☒ If Yes, please provide a brief summary of the impact? Where the impact identifies a requirement for technology, has an assessment been carried out (or scheduled) by the Enterprise Architecture Governance Group (EAGG)? Yes ☐ No ☐ 5.7 Environmental / Carbon impact Does the report / project / practice contain information that has an impact on any environmental or carbon matters? Yes ☒ No ☐ If Yes, please provide a brief summary of the impact? There will be a significant and unavoidable environmental impact of the loss of Ash trees over the next 10 years Report sets out the upcoming Operational Woodland Plan, which will outline opportunities for mitigating this loss and see the Council registering new planting sites with the Woodland Carbon Code to register carbon credits. 5.8 Communications impact Does the report contain any information that has an impact on the council’s communications activities? Yes ☒ No ☐ If Yes, please provide a brief summary of the impact? Ash Die back will be a significant landscape change that will need to be communicated with communities through the boards. Much Ash risk also lies with private landowners although the impacts of these could be additional risk to Council assets such as roads. Comms to make landowners aware of their responsibility will also be required 5.9 Risk impact Is there a risk impact? Yes ☒ No ☐ If Yes, please provide a brief summary of the key risks and potential impacts, highlighting where the risk(s) are assessed and recorded (e.g. Corporate or Service or Project Risk Registers), and how they are managed? Inspections of tree assets in line with the Tree Asset Management Strategy is reducing the overall risk of tree failures in high risk zones. Ash Dieback Disease is a known risk that we are seeking to reduce by adopting and resourcing an Action Plan for Ash Dieback.