There has been too much knee-jerk reactionary panic to the arrival of ash dieback Chalara fraxinea to Britain’s shores, and a tedious jostling for position and profile between NGOs and others that supposedly put our trees first. Just days before it became a reality I wrote about the inevitable spread on ash dieback beyond the initial sightings in tree nurseries, and subsequently about its likely impact. The news about the disease has since become a very major story in Britain’s media and a widespread topic in daily conversation.

Looming treescape
Planning for a positive future for Britain’s trees and forests

Here is my proposed ten-point plan, in which some actions may surprise some.

  1. Do not fell mature ash trees in diseased areas.
  2. Lift the indiscriminate import ban on ash trees.
  3. Increase urgently funding for genetic research into resistance to ash dieback.
  4. Support research into understanding the pathogenic fungus Chalara fraxinea.
  5. Provide silvicultural practice guidelines in dealing with ash dieback.
  6. Initiate public education about tree health and biosecurity.
  7. Support citizen science initiatives that enable monitoring of tree health.
  8. Provide funding sufficient to implement the Forestry Commission Tree Health Strategy (see below).
  9. Bolster Forest Research science funding into tree health.
  10. Stop blaming the Government for ash dieback.

1. Do not fell mature ash trees in diseased areas

Killing trees in areas around diseased trees could wipe out any of nature’s in-built resistance to Chalara fraxinea. It is clear from continental Europe that up to one-third of ash trees exhibit some resistance to ash dieback. Ash is a very genetically diverse tree species, unlike elm (which is why that species was devastated by Dutch elm disease), so we must give nature a change to display this resistance. Mature and resistance ash trees should be allowed to stand, allowed or encouraged (via tree breeding scientists if necessary) to interbreed and to produce our next generation of healthy ash trees.

Those trees that do succumb will provide fantastic deadwood habitat if allowed to remain standing (when safe to do so), or can be felled when convenient to provide highly-valuable timber when the market demands it, rather than the market being flooded due to mass-felling and the inevitable price crash.

2. Lift the indiscriminate import ban on ash trees

The phrase “shutting the stable door after the horse has bolted” comes to mind. The presence of ash dieback in our nurseries was known about since February. We may have been able to have prevent this had the ban been in place before 2012. Now, it is too late, and pointless given that the disease is loose in the ‘wild’. The disease will spread without much influence from an ash import ban, or even a moratorium on planting ash, which will only, at best, slow its distribution.

It is quite likely that the occurrences in the East of England arose by other means rather than on young plants. It can be spread by water droplets, bird’s feet, forestry and tree machinery, footwear, dog’s feet, car tyres and by wind. Its arrival in Britain was inevitable. Instead of a blanket ban I would like to see a selective control on young trees imported; allowing in only those that have shown some resistance to the disease.

3. Increase urgently funding for genetic research into resistance to ash dieback

We should increase collaboration with international scientists. Some involvement with the Fraxback programme (see below) exists and should be built upon. Work by the Future Trees Trust on selective breeding on ash should be supported further; specifically to enable disease resistance trials to take place, ideally jointly with other European partners.

4. Support research into understanding the pathogenic fungus Chalara fraxinea

As in 3., increase collaboration with international scientists, and recognise that increased funding may be necessary.

5. Provide silvicultural practice guidelines in dealing with ash dieback

We must build on the excellent work done in continental Europe where there exists over a decade of experience in dealing with the pathogen to provide straightforward silvicultural guidelines to forestry practioners (e.g. Thomsen and Skovsgaard 2012). We need some clear guidelines both for foresters and arboriculturists in how best to deal with the disease and with diseased trees.

6. Initiate public education about tree health and biosecurity

There exists widespread ignorance about tree health and biosecurity among the public, and a lack of knowledge by decision makers concerning the capacity of the public to respond positively to increasing biosecurity measures in the countryside. Research is required to tackle the latter, and a more co-ordinated response required by the sector to tackle the former; leaving any chest-beating and self-promotion behind.

7. Support citizen science initiatives that enable monitoring of tree health

The age of the citizen scientist is upon us. There are a number of schemes and initiatives running currently that provide the wherewithal for members of the public to take an active part in monitoring tree health across the country. While recognising the irreplacability of the trained scientist, we must also recognise the increasing strains placed upon our beleagured tree scientists from ever-decreasing funding (and therefore manpower) coupled with ever-increasing tree health issues. Some examples of citizen science initiatives include Ashtag which has been set up to monitor ash dieback, and the broader tree health initiative TreeWatch – Adopt an Ash.

8. Provide funding sufficient to implement the Forestry Commission Tree Health Strategy

The Forestry Commission has developed an excellent Tree Health Strategy. This now needs to acted upon urgently and funding provided sufficient to ensure that Britain’s trees and forests are protected and enhanced into the future. See link below.

9. Bolster Forest Research science funding into tree health

During 2012 alone tree scientists at Forest Research have had to face an Asian longhorn beetle outbreak, sweet chestnut blight, and ash dieback. This is in addition to oak processionary moth, Phytophthora ramorum in Larch, and acute oak decline that were already big-enough problems to tackle. It is important to recognise that it is not just the science work itself that is stretched, when delivered by an already small team, but that every new disease or pest demands time. Time in dealing with the media, with politicians needing briefing, from concerned and well-meaning members of the public and organisations. Every meeting attended and briefing note produced is less time spent on finding out more about the problem and how it can be tackled. Every budget cut stretches further their capacity to deliver and demands more time spent away from the science trying to raise external funding.

The team of scientists at Forest Research are an amazing resource but anyone who is lucky enough to deal with them will know that they face an impossible task, even before “the biggest story since Dutch elm disease” entered their work stream. They need more funding so that their team can be expanded and better resourced. A key objective from the Tree Health Strategy (see 8.) is “secure sufficient resources to ensure that biosecurity is not compromised.

10. Stop blaming the Government for ash dieback

Nothing will stop the spread of ash dieback across Britain, and given its relentless spread from Eastern Europe over the past 20 years, its arrival on our shores was inevitable. The current actions led by Defra will, at best, only slow its spread. Pretending that ash dieback in Britain is the fault of Government is simply shallow chest-beating, and everyone knows it. Let’s get on with the actions above by working together for the good of our trees and forests.

Gabriel Hemery

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  1. Finally someone who is talking some sence. I ‘am currently doing my disertation on how the tree diseases are effecting the british Landscape, and all I’ve found is blame.

    1. Author

      Thanks for your comment Tom. Of course I wrote this soon after the outbreak was confirmed in Britain, and there has since been much more written and now provided as formal advice. It will be May/June this year when we start to get a real picture about the status of the pathogen in Britain. Good luck with the dissertation.

  2. I am in mind at the moment of the Ash dieback I regularly saw in hedgerows during the early 1990’s, as I began a career in countryside management. This was always blamed on root disturbance and bioaccumulation from agricultural processes. Having spent 25+ years in woodlands, managing them and extracting, I have seen natural regeneration dieback at around years 3-5, but not much notice was taken. Again this was in areas of traffic from people,animals and occassionally vehicles, again maybe down to root disturbance. I also know the H. albifidus fungus has been associated with the Ash since time in memorium as the decomposer of the shed leaves. This all seems to come at a time when production forestry for biomass was about to use the Ash as its “cash crop” and get out clause for a more sustainable energy producing future. Am I so cynical to think its a government plot in identifying a bad guy to keep us using fossil fuels? I have also noted that there is government and scientific talk that biomass is no longer considered to be the “carbon neutral ” solution we crave.

    1. Hemp would be a much better for biomass than ash. We should be cultivating more of that, growing a mixture of male and female plants would make any cannabis planted within it rather useless (the drug level drops to a nominal amount when the female plants are fertilised).
      It grows fast and in a wide range of conditions, suffers few pests or diseases (at the moment anyway), holds together the soil, can be used as a fibre in a wide range of products and is good for biomass.

      1. Hello again AK and all.
        I am not going to be critical here but I do think this idea of burning anything to generate electricity is a little bit old fashioned to be honest. Almost prehistoric in fact. Besides we have a perfectly good inferno going already. Its called the sun.

        Now what are we going to do about the governments intention to prevent the judicial reviews from happening? If we disagree with the governments plans we have a democratic right to object. After all they are our employees. If they go ahead with their intentions, claiming its to stimulate economic growth then we will see the return of the madcap ideas from the past. Forest sell off anyone? What about the clear cutting of forests for biomass? They have the ideal excuse to push that one. All in the interests of the natural environment. Burn off all those nasty ash trees to stop the spread of the disease. If this government gets anymore erratic in its behaviour I fear we will have to have them sectioned under the mental health act.
        Meanwhile we have to get organised to reduce the spread of ash die back and gather the information we need to protect our landscape and wildlife as well as the ancient ash trees.

        I will be looking at the worldwidewood site later.

  3. Your advice is exemplary. As a small mixed woodland owner with thousands of ash trees, my policy will be 1) continuously survey and thin infected trees, thereby automatically selecting the most resistant, and 2) sell firewood direct to end users only, and stop selling all firewood through agents, as a basic biosecurity measure.

    In another life I am an information intelligence analyst, so I thought it would be useful to curate and analyse what is being said about the phenomenon, both as a way of dealing with the emotional grief by a process of abstraction, and of providing all interested parties with a concentrated, multiple perspective intelligence resource. Your advice happens to be the first entry and it literally ticks a lot of the boxes! Thank you. (Note the drop-down Categories being monitored.) My purpose is to start a process off, so the site becomes a locus for sharing knowledge, learning and experience across Europe, perhaps crowd sourced and crowd funded. If you have any ideas of how to proceed … meanwhile I will continue inputting the first few.

  4. You never mentioned the ash being so old. I presumed they’d be younger than that since you don’t see too many old ash (only a few around here in field boundaries). Trees have been imported for hundreds of years, and “improvement” of existing species has been carried out by nurserymen since at least the Victorian era if not earlier. This generally resulted in straight-growing specimens from Central Europe being planted for forestry purposes, the “improvement” of English oak is well documented in Rackham’s ‘Woodlands’. It’s a big book, but I couldn’t put it down.
    Don’t forget that this has always been a nation of rather keen plant collectors.

  5. So if only 1/3 of ash trees die from it, that could indicate poor genetic diversity in the Danish population which suffered 90% mortality. I suppose Jutland acts as a natural bottleneck.
    But what about Britain? Are our ash any more diverse than those of Denmark? Compared to most of Europe, I’d think they’d be less diverse, with the highest diversity probably being at LGM refuges in Southern Europe.

    1. Just a thought but trees like any other life form will evolve over time to acclimatise or adapt to any given environmental pressure. I have 5 large ash trees in my garden. They are only separated by a few dozen metres. However there are three distinct variations among them. Two lose their leaves earlier than the other three. Whilst one is particularly reluctant to losing them until virtually all the other trees have lost theirs. Also they have a distinct colouration difference of the leaves. They also burst bud at different times as well. The two early trees take longer to develop a full canopy than the other three. The three have darker leaves than the other two. They are all about the same age apart from the one which resists autumn longest and this one is the biggest tree of the five.
      Now I am not suggesting this indicates a resistance to anything or some substantial variation but I suspect that they are two or possibly three hybrids in just that small group. They have quite distinct differences in their biological behaviour. If this is so obvious in such a small area as my back garden then there is every possibility that there are sub species around the country with quite distinct variations, possibly ones which give the ash tree a resistance to ash die back disease, spread over much greater areas.
      As my mother said earlier today the only way to develop a natural resistance to anything is to endure a dose of whatever it is that’s going around. In other words she said pretty much what Gabriel had said about not cutting them down as a precautionary measure. Let them stand and make rapid use of citizen scientists to record the changes and adaptations as they occur, also collecting seeds of any that display a tendency to survival against this disease despite the odds.
      I don’t like the idea of losing one ash tree let alone the entire population of them but if this disease is to be countered then we need to stop relying on this clearly incompetent government and take the lead ourselves. We need to start looking at the trees to find out which ones are dying and which ones aren’t.
      As for genetic diversity think of it this way. When the last ice age departed these lands of ours the tree species all spread from the South to the North by propagation of what ever parent tree happened to be closest to the trailing edge of the ice sheets. As these spread north they simply multiplied the species at the South coast all the way up North. So in theory there could be only one ancestor to all our Ash trees and then again there could be dozens if not thousands depending upon how many individual ash trees of different provenance spread North. The only real way to tell is to genetically test those trees with the most distinct variations in their make-up.

    2. PS What is an ‘LGM’ Refuge?

      1. LGM – Last Glacial Maximum (“Ice Age”) –

        I suspect those trees in your garden might be derived from a mixture of local and cultivated stock. Cultivated plants have a different provenance and slight adaptations to their local conditions, but nurseries import them from all over the place and so they’ll be passing their genes on to some of the next generation of ash trees.

        In some species they’ve found clear local adaptations. I can’t remember which species (I think it was downy birch), but they found that ones had some local adaptations. They planted ones from France in Northern Norway and vice versa and found that they had different budding times and didn’t thrive in their introduced sites despite being the same species.
        Rackham did a good book on woodlands and it included info on the genetic diversity and LGM refuges if I remember right. In Europe it was Iberia, Italy, the Balkans and Caucasus that acted as refuges and these areas show the greatest diversity today.

        1. Ah thank you for that. I have so many acronyms in my world to deal with. Getting forgetful in my old age. Speaking of old age the ash trees in my garden are, to the best of my skills and experience to judge, at least 100 years old if not older. So tell me, how did they get to be cultivated from introduced stock? Were we as a nation importing Ash saplings from overseas way back then? As for locally cultivated I am certain that there would be more of them around my property. I am inclined to believe they were self seeded into an ancient hedgerow on either side of my garden. Several saplings also exist alongside the main ones but are very much younger and have come from the existing trees. Having lived here for 14 years you kind of get used to landscape characteristics. There are no other ash trees within a few hundred yards of my garden, which incidentally is on the edge of a village and the garden has existed since around the 16th century at least, if not earlier. The remains of original ancient buildings still exist in the main garden. As does the North wall of one main building which is now the North boundary wall to the garden and stands at over 15 feet high. What was once the inside of the building is now part of the larger garden. I have uncovered the occasional section of foundation wall where the building once stood. All very unusual.
          I also have ‘Ancient Woodland’ by Oliver Rackham but to be honest I haven’t read it all. Its a big book and time is not very generous. I will endeavour to have a look at the genetic diversity information.

  6. By allowing the Ash die back disease to proliferate without recourse to some form of genetic (not profiteering biotechnology incidentally) research will end up with the perpetual Dutch Elm syndrome we now see year after year as the root stocks of English Elms struggle to grow for a few years only to succumb to the pernicious infection. We could have removed millions of Elm trees but back then we had no funding nor had we any technological know how to even begin to look into the genetics of such things. The disease spread to fast for the antiquated research machinery we had to even stand a minor outside chance of keeping up with it. Let alone stopping its spread.
    The only sensible course would be to encourage the strongest and most resistant strains to this scourge to proliferate and the Ash trees that have these tendencies may well be among those that the government is currently demanding landowners cut down. Incidentally I always blame the government, not necessarily for not acting sooner but for pandering to the fat cats profits over the needs of the nation with regards to such things as funding for Forest Reasearch. The closures of several CEH research stations and a whole host of other disgraceful sabotage.

    As for the citizen science well this needs some form of coherent framework to ensure consistency of approach and also a consistent biosecurity system applicable to all. Yes the disease will spread but lets not go bonkers and give it a hand to spread even quicker. Time here is of the essence if we are to even notice the differences between the trees with no resistance and those with some. After all genetic traits may well come from more than one tree and it may well be that we have to cross several Ash trees to build a good robust genetic resistance in one hybrid species that will have all the qualities of the original Ash trees but also a combined resistance against the Ash Die Back. Time is already short so it makes sense not to squander it.

  7. Hi Gabriel,

    Last week in London at the National Forestry Stakeholder Forum, Save our Woods and the Forest Campaigns Network directly asked some of the organisations to please, stop the blame game and instead unite to work on this with Govt and specialists. SoW have also directly asked the Ministers to give the platform created by the media storm about Chalara to the specialists and resist any political knee jerk reaction.

    Organisations playing the blame game are treading a very fine line anyway. Aren’t ALL of them to blame for not verifying their supply chains? How did I know, over three years ago, and they didn’t that their nurseries were growing on seed in Holland before importing back to the UK?

    I hope that any funding generated by ‘their’ PR jostling will find the right home, in research.

    Great to see you taking up this stance Gabriel and for your insights into a possible best step forward. They tie in with the discussions I’ve been having with specialists and policy makers fighting the disease here in the UK and in Europe. Do you think that the Government could ever accept those as a way forward though?

    The public, as ever, are keen to be involved in whatever way is most helpful and are capable of understanding more than what is often presented to them. Here’s hoping that Ashtag is a success and can be rolled out to help with other issues.


    1. Author

      Hi Hen
      Thanks for the interest in this. I am trying not to blog while I finishing writing The New Sylva but its hard to ignore such an important phenomenon.

      I was pleased to hear that you’ve been busy too. I gather that Gov is developing a Practitioner Advisory Group on tree health as I’ve been asked to join. So good moves afoot there too.

      Best wishes

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