ASH Die ieback ….. Coming to a tree near you The Bookham Tree Wardens 10 th July 2019
What is Ash Dieback? Chalara: fungal disease from east Asia Arrived in Europe in the 1990s Spores dispersed by the wind Blew in from mainland Europe First in the UK in 2004 or earlier Arrived in Surrey in 2014 Food and water fail to move up the xylem in the stems causing dieback Hymenoscyphus fraxineus previously known as Chalara fraxinea Healthy leaves
The size of the problem In Europe for 20 years Wiped out 90% of the ash trees in Denmark Will do the same in the UK We have est. 150 million mature ash trees And 1.8 billion young trees and saplings 4.1 million are urban ash trees 4 million alongside roads Dutch Elm disease: UK lost 30 million trees Biodiversity value of ash: hosts 955 species, 451 red list species, 45 are only known to occur on ash trees and 62 highly associated with ash Queen Mary University of London have Minute spores of Hymenoscyphus fraxineus (Chalara) sequenced the ash genome
Identifying Ash Trees – ash keys The seeds are called Keys They remain on the tree well into winter Often thought of as weeds Allowing young trees to germinate could help save the species 2-3% of trees might be immune to ash dieback We will lose the rest…
Identifying Ash Trees – the leaves and bark Young trees often grow in groups The leaves are pinnate – they have many leaflets along a single stalk Leaves are paler than oaks or beeches Young trees have a smooth bark Mature ash trees have long straight trunks Mature trees have a uniform ridged bark A healthy ash tree leaf
Mature tree bark Young tree bark
Looking for signs of Ash Dieback Leafless sticks at the top of a tree Bunching of leaves with bare twigs below Shoot wilting, leaf necrosis Trees with fewer leaves Sudden branch drop Diamond lesions Mauve and/or orange sticks
Signs of ash dieback Lesions Sick and dying leaves
Health Classes of Ash dieback: Classes 1 and 2
Health Classes 3 and 4 (Cla (Class 4: : 25% – 0% remain inin ing canopy )
Where is your ash tree? • Is it near a road? • Is it over a driveway or footpath? • Does it have a Tree Preservation Order? • Mole Valley website list of TPOs • Owners with ash trees near footpaths, pavements and public rights of way need to be particularly vigilant • In late summer check your ash trees: if a branch or section has no leaves it is probably dead
Your responsibilities • To avoid injury to others as a result of tree failure • You have a ‘common law’ duty of care to ensure neighbours, visitors and trespassers are safe • Avoid disturbance to bird nests, bat roots, wildlife • Keep deadwood to help insects survive: ash dieback is their Armageddon! • Don’t fell if you don’t have to
If your tree shows signs of ash dieback… • Find a Professional for diagnosis and felling • Compost, garden bin or burn your leaves • Offer your wood to neighbours • Replant ASAP to minimise landscape loss • 3/2/1/ formula: Plant 3 new trees for loss of a large tree, 2 for a medium tree and 1 tree for a small tree • Use British grown trees: native aspen, alder, field maple, sycamore, birch, rowan, oak, disease resistant elm
Councils and Offic icialdom Mole Valley District Council: - is attending to ash dieback on its sites - Holds the list of Tree Preservation Orders Surrey County Council: - refers one to the Forestry Commission website Network Rail: - has 10 million trees predominantly ash (20%) and oak - spend £42 million per year on tree maintenance
Surrey Wil ildlife Trust • Spent £26,146 on Ash dieback in Norbury Park • Generated an income of £19,998 • Wood used for biomass production • 60 trees sold as logs for furniture • Awaiting natural regeneration Ash dieback on Fetcham Downs in 2014
Oth ther Councils? Kent has 500,000 trees on roads and by-ways Surrey will have a similar amount Leicestershire County Council have put aside over £5 million to deal with ash dieback • additional survey work • felling dangerous trees • additional staff time to work with private owners to ensure dangerous trees are removed • staff time to deal with increased public reaction/requests to fell • staff time to deal with ash trees that have TPOs • cost of replacement planting • additional staff and consultant costs • communications and consultation to explain ash dieback to stakeholders Counties with dieback planning are: Devon, Herts, Kent, E Sussex, W Sussex, Suffolk, Norfolk, Leics., but not Surrey!
A County Council estimated work and costs (Unnamed council) • Woodland adjacent to public areas: 5968 trees will cost £1,468,000 • £400 cost of removal per tree • Replacement tree planting (over • £34,478,905 total cost 80,000 trees) will cost £1,246,905 • 6,020 verge trees x75% mortality • 1115 ash trees removal and will cost £1,499,000 grinding of stumps will cost • Private ownership adjacent to £158,168 highway 120,000 will cost • As Mr Gove is no longer in the £29,880,000 leadership race perhaps he has • School grounds 1546 trees will cost some time to consider tree matters £385,000 in Surrey!
Links and Research: Ash Dieback https://www.treecouncil.org.uk/Portals/0/Ch alara%20docs/The%20Tree%20Council%20As h%20Dieback%20Action%20Plan%20Toolkit %20FINAL.pdf?ver=2019-02-11-124648- 123×tamp=1549889719913 Arboricultural Association Registered Consultants available at www.trees.org.uk/Find-a-professional
Oak processionary moth – what is it? • A non-native moth, Thaumetopoea processionea , from central and southern Europe, first seen in UK in 2005 • Established in Greater London and some surrounding counties • Huge infestations have arrived in Mole Valley, Ashtead, Bookham etc. • Eats the leaves of oak trees, causing significant damage • Primary concern is human (and animal) health
How to recognise OPM • Hairy caterpillars crawling around the branches or trunk in lines, nose-to-tail. • Often cluster together and build white, silk-type nests in the branches or trunks (not in the leaves) of trees. Nests turn grey over time.
Oak Processionary ry Moth – the dangers: Disturbing the caterpillars releases toxic hairs - Skin irritation - Breathing difficulties - Less frequently, serious allergic reaction 5-7% of population at risk of affliction, ranging from minor skin complaints to anaphylaxis Risk of exposure is highest in May and June Do not touch or approach OPM nests or caterpillars Keep dogs from rooting around tree bases - they suffer the same as humans
Oak Processionary Moth – The treatments: • Application of approved insecticide or bio-pesticide in spring (mid-April/May) to kill young caterpillars • Manual removal of nests by trained operatives in late summer after caterpillars have pupated, when all pupae are inside the nests Surrey County Council advice : ‘The Forestry Commission are responsible for dealing with this pest and all sightings should be reported to them .’ For pet owners the Blue Cross has a useful webpage https://www.bluecross.org.uk/pet-advice/dogs-and-toxic-oak-processionary-moth- caterpillars
OPM Treatments • Under no circumstances try to remove the nest/s yourself • in public parks and streets under EU law treatment is mandatory • Notifiy the English Forestry Commission on their TreeAlert web page • We were previously in a control zone but with the increasing outbreak the process is evolving
What is is Mole Vall lley Council il doin ing? • Prioritising high risk areas • Triggered a major crisis alert referring you to the Forestry Commission website • The Forestry Commission have stopped dealing with the problem on private land … they will not be funding spraying. Advice: if you have OPM on your Oak: - do not disturb the nests - contact the Forestry Commission or MVDC who will provide you with a list of FC licenced contractors - See our updated web page: - http://www.molevalley.gov.uk/ index.cfm?articleid=41072
Oak Processionary Moth • Spot it • Avoid it • Report it
Links and Research: Oak Processionary Moth • https://www.gov.uk/government/organisations/forestry-commission • https://www.gov.uk/government/organisations/forest-research • https://www.forestresearch.gov.uk/tools-and-resources/pest-and-disease-resources/oak- processionary-moth-thaumetopoea-processionea/opm-manual-4-biology-and-life-cycle/ • https://www.rover.com/blog/uk/uk-dog-health-warnings-processionary-caterpillar-outbreaks- discovered-south-east- england/?fbclid=IwAR0FpC3A4pK76Zk9Sg1l7wyG_agliD5m5gdcN9uH4mpIebhx787tqU7y-TE# • http://www.molevalley.gov.uk/index.cfm?articleid=41072 • https://www.surreycc.gov.uk/land-planning-and-development/countryside/advice/oak- processionary-moth
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