David Rose gave an opening talk on Dutch Elm Disease and the Future of Elm in Kent.

How many Elms were there and How many have died? 85% of Elms which were capable of being infected in 1968 died – 30 million trees. In spite of continuing losses, in East Anglia, East Sussex, Hampshire and South Downs (perhaps Kent) there are still Elms. The Isle of Man has half a million healthy Elms. Seed reproduces the species of Elm in Kent –Wych Elm –. The Wheatley (Jersey) Elm is planted in a lot of towns. The English Elm is the main species. Elms are produced by suckering only off one rootstock. Dutch Elm disease is genetic and will hit all the trees on one rootstock, sometimes up to 3 kilometres at any one time.

History of Dutch Elm Disease (DED) has been the focus of intense research for a century. It is not a new phenomenon. It was present in North West Europe in 1910 – severe in the Low Countries at first. Spread westwards across the Channel to UK in mid to late 1930s and then on to America in 1937. In the late 1960s a new species of fungus appeared. The old disease was transported to USA and Canada in the form of wood and logs exported. This then spread eastwards into Turkey, Moldavia and the Baltic States.

The new fungus spread from America back to the UK in the 1960s. At the same time a separate fungus spread from Moldavia. This shows what can happen when goods are transported around the world. From 1910-1930s there was a Pandemic petering out in the 1950s. Then in the late 1960s a more aggressive, more destructive new strain of disease arrived. Elms are susceptible to disease as soon as they reach a certain age.

In the countryside beetles carrying the fungus feed in twig crotches of healthy Elms passing on fungal spores. The trees wilt and are weakened providing breeding sites for the beetles which feed on the fungus under the bark. The adult beetles covered in spores spread the disease on. English Elm and Wych Elm are affected. English Elm is most vulnerable and the beetles only feed on Wych Elm when English Elm is not available. But Wych Elm will also die. The answer is to prevent the beetle from entering the tree. There are 3 species of Elm beetles S.scolylus carries the most number of spores. Only 5 beetles will guarantee infection. Kent was hit by this beetle. The S.multisbriatus fungus which is controllable infected the Isle of Man Elms. Nothing can be done to control bark beetles on trees. The Wych Elm survives to a greater size before the beetles feed on it. The beetles thrive in temperatures above 18C but prefer 25C. Typically cold wet summers deter the beetle from flying, so global warming may be a factor in the spread of the disease.

The fungus has a competing fungus itself which pushes out the beetles so that no Dutch Elm fungus grows and reduces the amount of infection. When beetles fly off they do not go specifically for Elms – it is random until they find an Elm and each time spores are knocked off so if Elms are widely spaced more spores drop off and the disease is not passed on.

Current Control Strategies
Expensive injections at £5,000 to £6,000 per tree. Fungicide is injected under pressure based on circumference of tree and takes 12-14 hours using very expensive material and has to be done every 2 years. Used for high value trees in town areas but too expensive for countrywide use.
Plant hybrid Elms which are resistant to disease. These tend not to look like English or Wych Elms – do we want to grow more exotic trees? Beetles do not feed on Asiatic Elms and the fungus does not kill the trees – they are resistant to both.

More sanitation felling to prevent disease is not possible. Once it goes down to the bottom of the tree then it spreads on through all suckered trees. E.Sussex, Brighton, Hove, Eastbourne do still use sanitation felling. There are strict restrictions on movement of logs/wood which is successful in some areas.

Current Research
D-Factors. Dutch Elm disease has a disease itself. Infected with virus-disease factor. Affects the new aggressive disease.
20 different D-Factors associated with fungus. No universal d-factor found so far. This could form the basis of biological control. Dutch Elm disease is evolving. The Eastern form has swept westwards and swamped the old form of disease. The old disease no longer exists and has been totally absorbed by the new fungus. Each time the fungus changes slightly and the D-factor also has to change.

Genetic manipulation. Modify Elm DNA to create resistance or modify D-factors to produce universal D-factor. There is a difference between genetic manipulation (using what is already there) and genetic engineering (create something which does not exist). Research is continuing in Scottish University. Successful modified Elms have been produced to test resistance. It may be possible to extend this research to other Elms but difficult with those produced by seed. Has to be carried out in very controlled conditions so as not to produce something different altogether.

Possible Solutions
Sanitation with low infection and high resistance.
Selection of Wych Elms
New Elm hybrids
There is a German clone of an Elm which is quite resistant – looks like a Wych Elm but has Asiatic Elm included.
In the Himalayas an entirely new species of fungus has been found which is twice as bad for our Elms but does not affect the Himalayan Elms.

Suggestions for trees in Whitstable – Hornbeam, Oak, Small-leaved Lime or look around at what is already growing locally. English Elms are large dominant trees and may not be suitable for a townscape.
Woodland Trust Native Tree shop supplies fair priced individually bought trees but if a tree-planting scheme is planned, small tree specialists can supply larger amounts at a good price.

Hornbeam would not be permitted in a conservation area unless already present. Claysite woods (Epping Forest) are rich in Hornbeams and grow in Blean Woods.

Small-leaved Lime is rare in the UK. (Have distinctive bark and pronounced veins on leaves).

Male and female varieties of the native Black Poplar is a good choice for waterside sites and river valleys.

Jon Lambourne
Trees for Whitstable?

Trees can provoke varying attitudes in people. Thoughts should be focused –
Why – beauty – wildlife – shade – reduce pollution – moderate extremes of climate – increase property values – because there aren’t enough trees in Whitstable. Is Whitstable treed or treeless? Jon felt there were lots of trees in Whitstable.
Where - in gardens, streets, open spaces, individual trees, groups of trees, woodlands.
What – constraints such as site, soil, coastal exposure, space, buildings, boundaries guides the choice of species. The Woodland Trust can offer advice. Notcutts offer plants for seaside sites, Barchams of Ely stock cockspur thorn, sea buckthorn. For coastal sites – Ash, Aspen, Hawthorn, Holly, Rowan, Sycamore, Eucalyptus, London Plane, Poplar, Oak, Whitebeam, Lawson Cypress, Pine. What already grows? – Sycamore, Horse Chestnut, Lime, Oak, Poplar, Willow, Cypress also Tamarisk, Bay, Yucca, Cordyline, Stags Horn Sumach. In the countryside no alien species should be grown but there is a wider range for the town. Forestry Commission feels that the upright Hornbeam would tolerate coastal exposure. (Holm Oak is a naturalised evergreen but not strictly native tree). Small-leaved Lime has an aphid problem but attracts bees. Plant in small copses but too large for townscape. Hornbeam can be grown in sheltered conditions.
When – October to March for bare-rooted trees. Anytime for container grown trees.
How – Mix compost with local (clay) soil; keep weed free; water when needed (good soaking once a week); keep stakes low; loosen the stake ties as tree grows; prune if required
Then What Will the Council look after trees? For example a Robinia tree which has outgrown its site in Knights Alley). Richard Davidson is officer in Council responsible for Council trees in coastal areas. Important that advice is sought regarding siting of appropriate trees. Advice available from: Woodland Trust – Community Woodland Network – British Trust for Conservation Volunteers – International Tree Foundation – Tree Officer

It was pointed out that it is difficult to encourage the Council to replace trees which have been lost through old age, footpaths being too narrow, subsidence and then the space tarmaced over. Individuals or groups should contact Council on this matter. If it can be shown that people are keen to keep trees in public areas then Council will help. There is no policy to automatically replace public trees.

Challenges
Establishment – vandals – shade – fear of trees – development – subsidence

What makes for successful planting?
Right site – appropriate species – quality stock – aftercare

21 October 2005 marks the 200 anniversary of Battle of Trafalgar.
The Trafalgar Woods project plans to create 27 new woods across the UK named after the 27 wooden ships in Nelson’s fleet.
It is planned to involve local children in the Tree for All scheme where 12 million trees will be planted a million by children which will teach children about the link with our naval history. The Victory and other ships at Trafalgar were constructed at Chatham Dockyard. The site for Victory Wood was first thought might be in Hampshire (because of Portsmouth) but no land was available. Schools without green areas could have a dedicated area in the woodland which they could revisit. Schools can also get copse and hedge packs from the Woodland Trust.

The woodland at Lamberhurst Farm (within Blean Wood complex) was destroyed over the last 25-50 years. It is necessary to raise £2.25 million to buy, restore and plant, provide car parks etc. and include perpetuity money for the future. Victory Wood will lie between Ellenden Wood and the national nature reserve at Blean Wood. It is hoped that planting will start next year – there will be public planting days and schools can get involved. Contractors, public and schools will plant 2-year-old saplings. Tress will also be allowed to seed from adjacent woods - Oak, beech, and hornbeam.

Woodland Trust could help with ideas for improving Duncan Down which is a registered village green. The Whitstable Society could get copse and hedge packs for Duncan Down. It was pointed out that new saplings are not sustainable by Council but other groups may be interested. Community Woodland Network helps small open areas.