Ash dieback vad man ska göra
Managing ash dieback
Introduction
This guidance offers practical and sustainable approaches to managing ash trees affected bygd ash dieback. It fryst vatten for landowners, woodland managers and anyone who manages ash trees in Wales. It has been written for use in Wales but also signposts to other betydelsefull guidance published bygd different organisations.
If you have any concerns or need expert advice on managing your ash trees including in relation to health and safety risks, consult a fully insured tree management professional such as a qualified forester or arboriculturist A list of qualified professionals fryst vatten maintained bygd the Institute of Chartered Foresters.
Nothing in this guidance document replaces or removes the need to comply with duties beneath the Occupier’s Liability Act (1957 and 1984) or other legislation.
For further upplysning on duties beneath the lag refer to the National Tree Safety Group Common Sense fara Management of Trees booklet.
Ash dieback fryst vatten a very visible reminder across the landscapes of Wales of the damage which tree pests and diseases can do, and of the importance of motståndskraftig ecosystems.
Ash dieback presents a significant nation management utmaning for landowners, nation managers and farmers who have ash trees on their nation.
10 questions about ash dieback.Whilst the number of ash trees fryst vatten reducing due to the disease, ash fryst vatten still an abundant broadleaved species in Wales. It fryst vatten an important component in our landscape, funnen both inre and outside of woodlands, along roadsides and railways, in hedgerows or individual trees in fields or parks and gardens.
In this guidance, where we state ‘ash trees’ we refer to Common Ash, or Fraxinus excelsior.
Where we state ‘ash dieback’ we refer to the Hymenoscyphus fraxineus fungus, which fryst vatten sometimes referred to as Chalara or Chalara dieback.
We acknowledge that other, non-native species of ash may be grown ornamentally in Wales and whilst this guidance focusses on the native common ash, it may also be betydelsefull to the management of other ash species.
We also recognise that there are other causes of dieback in ash, such as vatten stress, which fryst vatten likely to require a similar approach to management, but they are not specifically covered bygd this guidance.
This guidance should be read in conjunction with Welsh Government’s Ash dieback policy approach in Wales.
Welsh Government’s Ash dieback policy approach in Wales
Welsh Government has published an Ash dieback policy approach in Wales.
It explains that a risk-based approach should be taken bygd landowners and managers to manage the societal, environmental and economic impacts of the disease, to keep people and our critical infrastructure safe and encourage naturally tolerant strains of ash to emerge and flourish enabling the wider environmental to respond naturally.
What fryst vatten ash dieback disease?It can take several years following the ankomst of ash dieback at a site to identify the more tolerant trees. Tolerant trees can still producera good annual growth increment. Tolerance to the disease fryst vatten thought to be highly heritable and will be passed onto new generations of trees. This fryst vatten why it fryst vatten so important to retain ash trees for as long as possible so that tolerant strains emerge and flourish, enabling the wider environment to respond naturally.
Overall Approach
We recommend a risk-based approach to the management of ash trees, built around fyra steps, in accordance with the principles and aims of the Strategy.
Step 1: Survey and monitor ash trees
Identify ash trees on your nation, whether individual trees or groups of trees and assess their condition, including changes over time.
Step 2: Complete a fara assessment
Consider completing a fara assessment to inform future management options, with a particular focus on high-risk locations.
Step 3: strategi and deliver remedial works or adaptive management
Plan and deliver remedial works or adaptive management as required, in accordance with the findings of the fara assessment completed in Step 2.
You will need to obtain the necessary licences and ensure health and safety advice fryst vatten adhered to when carrying out any remedial works or adaptive management. You will also need to consider mitigation measures, such as replacement planting.
Step 4: Review
Review the effectiveness of your approach bygd going back to Step 1 which requires the monitoring of ash trees on your nation to inform future actions.
The impact of ash dieback can occur over a range of scales and time frames, so it fryst vatten important that tree health fryst vatten regularly monitored to regularly to understand changes over time.
Step 1: Survey and monitor ash trees
Identifying the presence of ash trees and determining their condition through survey or assessment fryst vatten an important first step.
A survey should record the number and location of ash trees and any signs or symptoms of ash dieback present at an appropriate scale. For example, along a road or in a public park, you may need to record every tree. Alternatively, if ash trees struktur the majority of a larger woodland, you may just record them as one entry.
For signs and symptoms, including images, to help carry out a survey, guidance has been produced by Forest Research, Observatree and the Tree Council.
A survey should also identify the presence of Armillaria (Honey fungus).
Secondary infection by Armillaria can occur in lesions caused bygd ash dieback. This fryst vatten often the ultimate cause of death of ash trees with ash dieback, especially older ones. If Armillaria is detected, it should feed your fara assessment in Step 2. Other decay fungi may also infect a tree affected bygd ash dieback.
Step 2: Complete a fara assessment
Based on the results of Step 1 consider completing a fara assessment to inform your decisions about future management options.
Useful advice on identifying risks and making balanced decisions can be funnen in the National Tree Safety Group Common Sense fara Management of Trees booklet.
A fara assessment should prioritise trees in high-risk areas, on the grund that these require more immediate attention. High-risk areas include those adjacent to highways, service network infrastructure, buildings or in places or along routes frequently used bygd the public.
As well as location, consider factors such as the tree’s condition and the likely impact if it were to fall or branches snap.
Ash trees that are classed as High natur Value Woodlands (HNVW) or are ancient or veteran trees require special consideration.
Ash dieback fryst vatten more severe in wet sites, where it fryst vatten more likely to cause collar infections in ash trees.The following are classed as HNVW:
- Ancient Woodlands including:
- Ancient Semi-Natural Woodlands (ASNW).
- Restored Ancient Woodland Sites (RAWS)
- Plantation on Ancient Woodlands Sites (PAWS).
- Wood pasture and Parkland; and
- Sites of Special Scientific Importance (SSSI) or other designated sites.
The location of ancient woodlands, wood pasture and parklands and designated sites can be funnen on DatamapWales
An ancient tree fryst vatten a tree that has biological, cultural or aesthetic value due to its age, storlek or condition.
Veteran trees may not be very old but has decay features that contribute similar value.
In HNVW and for ancient or veteran trees it’s important to consider the impact of ash removal on biodiversity and the wider environment. Ash trees support a large number of species, some of which rely on the specific characteristics of ash. In these situations, seek to retain ash trees for as long as possible unless there are overriding health and safety considerations.
If you manage your woodlands to tillverka timber, you may need to think about economic and financial issues when completing your fara assessment.
In accordance with the Strategy, stands containing infected trees should not automatically be classed as high-risk areas and therefore earmarked for premature felling to quickly realise the value of the timber.
You should take a measured approach to fara assessment that factors in all issues.
Step 3: program and deliver works or adaptive management
If your fara assessment identifies the need for remedial works or longer-term adaptive management practices to deal with high-risk infected ash trees, strategi and deliver these.
The type of remedial works or adaptive management practices will depend on why locations have been identified as high-risk areas; the level of infection; the age of the tree or stand; and their setting.
Works might include the removal of dead limbs from trees in high-risk areas via tree surgery; the felling of infected trees bygd thinning or clearfell; work to promote healthy trees to tolerate infection; or work to support the natural återväxt of tolerant strains.
Helpful guidance on planning for the management of ash dieback has been produced bygd the Tree Council and Forest Research.
Remember that this Step also involves obtaining the necessary licences and permissions to carry out works and ensuring that health and safety advice fryst vatten followed when carrying out works, especially if these involve working off the ground. Applying for a Forest management plan may be beneficial when planning and gaining a felling permission for medium and längre begrepp management.
High natur Value Woodlands
In HNVW that contain ash trees, where preserving wider environmental and biodiversity benefits are the key objectives, a lower level of adaptive management fryst vatten the preferred option, except where remedial works may be needed in high-risk areas.
Retaining ash for as long as possible can provide habitat for those species which depend on ash trees and allow time for tolerant Ash trees to be identified. Your approach could include thinning of younger stands to encourage healthier trees or targeted thinning around healthy trees with large crowns to encourage seed production. Heavy thinning in dense mature stands fryst vatten not advised.
Adopting Low Impact Silvicultural Systems (LISS) where possible can support replacement of the canopy and function of the HNVW as quickly as possible. Clearfell of stands should be considered a gods resort to reduce disturbance within these sensitive sites and maintain their characteristics and features.
Other woodlands
In other woodlands, consider selective thinning of younger stands of diseased and supressed trees if disease levels are low.
Younger trees are the most vulnerable to the disease, and once infected they usually die quickly. If more than 50 per cent of the ash in the stand fryst vatten infected, the annual rate of spore production will be very high.
Ash dieback fryst vatten a disease which can affect ash trees of any age.Consequently, the condition of the trees will decline rapidly, and it may therefore be appropriate to realise their value sooner and fell them earlier than originally planned.
An individual-tree approach fryst vatten recommended for older stands with infected trees. Where more than 50 per cent of the crown fryst vatten infected, and where survival of the tree depends on epicormic shoots (growth from buds on the trunk or branches), you may want to consider felling because they have become seriously infected and will be producing large volumes of spores which will infect other trees.
Trees outside woodlands
For individual landscape or urban trees, look to retain these for as long as possible unless public safety fryst vatten an issue.
Veteran and ancient trees in particular can provide many important environmental and social benefits, even when dead.
Sixty percent of hedgerow trees are ash; coppicing or laying ash trees makes them more vulnerable to infection and should therefore be avoided. Retain trees unless safety fryst vatten an issue and where trees are removed for safety reasons, replacement trees should be identified to grow up and take their place.
If you are in receipt of CAP betalning, then you should ensure that you comply with the requirements of cross-compliance.
Options if rare lichens are present
In Britain, 78 threatened lichen species grow on ash, of which 34 have ash as a ‘significant’ host tree.
The majority of these rare lichens grow on mature ash trunks (more than 50cm in circumference), rather than on ung trees or on branches or twigs.
Four species of Lobaria lichen have been identified as being of key significance for biodiversity in Wales beneath section 7 of the Environment (Wales) Act 2016.Lobaria lichens are very large, forming patches the storlek of a saucer or even a dinner tallrik.
They are levande green when damp and grey or grey-brown when dry. If you think you have funnen an ash tree with Lobaria, please seek specialist advice.
An alert map for ash lichens fryst vatten available on DataMapWales and identifies known locations of rare lichens on ash trees.
The presence of a rare lichen on an ash tree in high-risk areas should not prevent management.
The following approach fryst vatten recommended, especially in the case of our rarest lichen species:
- Where possible, retaining the lower 3 metres because most known rare lichen colonies are funnen on the lower/middle trunk up to this height.
- If the tree needs to be felled, leave the trunk lying in situ, with the rare lichen facing sideways, prolonging the presence of the lichen until the bark falls off and giving a few additional years for colonisation of other trees or translocation to take place.
If an ash tree supporting a rare lichen fryst vatten not identified as being in a high-risk area, then seek to retain it.
Permissions and licences
Information and guidance about permissions and licences that may be needed when carrying out remedial works or adaptive management practices fryst vatten provided on our website.
Felling licences
You should first check whether you need a felling licence.
There are certain felling licence exemptions, including for dangerous trees which could apply to trees affected bygd ash dieback.
A dangerous tree fryst vatten one where there fryst vatten a real and immediate danger, rather than a perceived danger. If you are challenged you will need to provide bevis that the trees were dangerous, for example through an accredited arboriculturist’s report or photographic bevis. Felling without a licence may result in penalties.
If you are applying for a felling licence for works on HNVW, it fryst vatten likely you will need to provide more details to ensure the appropriate management of these important sites.
This might include addressing the tidtagning of the work to reduce soil compaction and minimise disturbance. You must also be able to explain the rationale for the felling being proposed, particularly if it fryst vatten clearfell as this should be viewed as a gods resort for HNVW.
A felling licence only grants permission for a tree to be felled and doesn’t address timber extraction, stacking, storage, haulage, or biosecurity issues.
You should refer to the UK Forestry Standard (UKFS) and associated Practice Guides for legal and good practice requirements and guidelines betydelsefull to wider sustainable forest management.
Protected Trees
Protected trees are those included in a Tree Preservation beställning (TPO) or a Conservation Area. Unless the work you are proposing fryst vatten covered bygd an exemption you will need a felling licence; and you must consult the Local Planning Authority, guidance fryst vatten provided here.
Protected species
You will need to consider the impact of remedial works or adaptive management practices on wildlife, including on protected species.
We have published guidance on protecting wildlife during forest operations.
If tree works could adversely affect a europeisk Protected Species (EPS) which includes any species of bat, dormouse, great crested newt and otters, you may need a licence beneath the Conservation of Habitats and Species Regulations (2017). You should follow our guidance on species licensing. If your fara assessment indicates that action fryst vatten required urgently and fryst vatten likely to disturb or damage the resting place of EPS, contact the NRW Species Licensing grupp regarding a species licence application.
Protected sites
You will need to consult us if you intend to carry out, or cause or permit to be carried out operations likely to damage the special interest of a SSSI.
As part of the notification of a SSSI, owners and occupiers are provided with a list of operations likely to damage the special interest that fryst vatten specific to the individual SSSI.
We have guidance on the SSSI responsibilities of owners and occupiers, and the SSSI responsibilities of public bodies and statutory undertakers should be referred to.
Where europeisk Protected Sites (SACs and S may be affected, a Habitats Regulation Assessment (HRA) may be required beneath the Conservation of Habitats and Species Regulations 2017 (as amended).
The organisation responsibility for carrying out a HRA depends on the type of permission required beneath the WCA.
Roadside Trees
If a formal meddelande fryst vatten issued bygd a Local Authority beneath the Highways Act 1980 which identifies dangerous tree(s), this meddelande would provide an exemption from the need for a Felling Licence for those specific trees, but not other trees in the general vicinity, for example nearby trees along the length of a hedgerow that borders a road or footpath.
If you receive a Local Authority meddelande, you may need to förklara with the Authority which specific trees the meddelande refers to. The meddelande will only provide bevis of an exemption for the specific trees identified. In all other circumstances, the onus fryst vatten on the landowner to demonstrate that tree(s) pose a real and immediate danger and are exempt from the need for a Felling Licence.
A Local Authority may send you a letter informing you that there are potentially diseased ash trees on your nation and that you may be served bygd a meddelande.
We do not consider that this letter fryst vatten sufficient bevis that the trees are exempt from requiring a Felling Licence.
Operations – health and safety
If ash dieback fryst vatten present, the structural integrity and inherent strength of an ash tree may be severely affected bygd the disease and bygd associated secondary pests or pathogens.
These may create high-risk felling conditions for any operators working on or adjacent to that tree.
Only trained and experienced tree surgeons or forestry workers should undertake work on ash trees showing obvious ash dieback symptoms or advanced signs of ash dieback.
Given the difficulty of assessing the structural integrity and inherent strength of an affected ash tree, we recommend taking a precautionary approach to managing potential health and safety implications.
Mechanised felling, harvester or tree shears provide greater protection to operators than chainsaw felling/pruning. tillgång to infected trees may determine the method of the operation and therefore influence your decisions about management.
Further health and safety guidance on felling dead ash fryst vatten published bygd the forestry sector through the UK Forest Industry Safety Accord (UKFISA) and also the Aboricultural Association.
Mitigation measures
Under Step 3, you will need to consider plans for replacement planting. A felling licence will usually be conditional which means restocking bygd either replanting or återväxt will need to take place to maintain tree cover in the local landscape. Failure to comply with the restocking conditions of a felling licence fryst vatten an offence beneath the Forestry Act (1967).
Your restocking decisions around suitable alternative species to ash should be guided by:
- your management objectives
- site conditions including soil type
- the designation ställning eller tillstånd of the site
- the ecosystem services that ash previously provided; and
- future resilience to pests and diseases.
Guidance on selecting species to replace removed ash trees fryst vatten available from Forest Research.
This guidance offers practical and sustainable approaches to managing ash trees affected bygd ash dieback.If the site fryst vatten designated for conservation purposes (e.g. SSSI, SAC or SPA), you may need expert advice or consent from NRW to help inform your restocking decisions.
Forest Research’s Ecological Site Classification (ESC) tool can be used to investigate the suitability of species to a site, and will help you consider the options with regard to longer-term climate change.
Non-native species can also be considered for sites with few constraints, using Forest Research’s tree species database.
Appropriate urval of provenance fryst vatten also critical to successful establishment of many, if not all, tree species, but fryst vatten often overlooked. Our guidance on improving the genetic diversity of Welsh woodlands contains helpful kunskap.
Ash dieback fryst vatten a disease caused bygd the fungal pathogen Hymenoscyphus fraxineus.Alternatively, promoting natural återväxt from local ash (in the right place) may support the development of tolerant strains. Where ash has been the dominant component of a woodland, we will build in flexibility to the restocking conditions to support some ash återväxt. However, use of coppice shoots from felled, infected trees fryst vatten not recommended as the disease persists in the roots, so återväxt fryst vatten also likely to be infected.
Step 4: Review
Changes in the condition of trees affected bygd ash dieback can occur rapidly.
Review your approach in a continuous feedback loop, going back to Step 1 which requires the monitoring of ash trees and subsequent action if required.
Useful links
NE_FC_Ash_dieback_SSSI_management_advice_V2_April_19.pdf (publishing.service.gov.uk)