Guest blog – Ashes to ashes – Peter Marren

Kate Nicol [CC-BY-SA-2.0 (], via Wikimedia Commons
Like you, I expect, I cannot imagine what the landscape will be like in, say, ten years’ time. My window on the world is in Ramsbury, in the upper valley of the Kennet in Wiltshire. We have long been used to dying trees. Death took all our mature elms long ago, and they have gradually faded from human memory as though they had never been. Our horse chestnuts, planted in the late Victorian era, are falling to pieces and in most years turn brown by midsummer. Most of the mature crack willows died of a combination of canker and wilt a few years back. The alders are pegging out from yet another disease. Even the Leylandiahedges are looking sick.

Fortunately there was always the ash. What is it about the English climate that so suits the ash tree? Here they are at once the principal hedgerow tree and also the main large tree of watersides. They are just as much at home on the clay tops of the downs as they are down by the river. We have an ash pollard with a great hollow hammerhead trunk like a cave. We have crenelated and embossed ash stools on woodbanks that date from the early Middle Ages. For anyone with eyes to see ash defines the landscape here, in its grace, its beauty, and its infinite capacity for regeneration both from seed and from stumps. It is hard to believe that most, may be all of them, are doomed (and how, I wonder, are we going to feel about ourselves when that happens).

Brian Green [CC-BY-SA-2.0 (], via Wikimedia Commons
Ash dieback has been in the headlines for more than a week now and we now know roughly what is coming and from where. By November 5th the disease had been confirmed at 52 sites with more expected over the next few days. Many of the outbreaks are in tree nurseries but it has also been detected in mature woodland in Suffolk, Norfolk and Kent. Maybe it was all inevitable, once the disease had reached the Channel (although some pathologists say the spores are unlikely to have come from over the wide sea). It is obviously in the Government’s interest to make the case for the natural spread of the disease. What is certain is that it came in with infected seedling trees imported from Dutch nurseries. There was no screening for disease and, until the Government’s belated ban on ash imports last week, no import controls. Some 5.2 million ash saplings were imported to Britain between 2003 and 2011.

Let’s leave aside the idiocy of importing a native tree whose saplings grow by the million in local woods (it’s a real garden weed round here). What is worrying is the apparent blindness of those who have been busy planting broadleaved trees by the square mile in the conviction that they are helping to regenerate Britain’s heritage of woodlands. No one is a more enthusiastic planter of amenity trees than the Woodland Trust whose aim is to “support, nurture and encourage native woodland and making them more robust in the fact of climate change and disease.” The Trust buys its trees from nurseries. It claims to always ask for trees of local provenance, evidently not knowing, and certainly not asking, about how exactly these trees have been nurtured. In fact, many – to judge from the official figures, most – seedlings of ash and other trees are exported to Holland and other European countries for growing on and are then imported back for planting out. This practice is widely known and condoned in the trade, and was certainly known about by Defra and the Forestry Commission. Yet the Woodland Trust admits they knew nothing about it. In their innocence they feel themselves victims (pardon me, but I’d say the ash trees are the victims here).

Walter Baxter [CC-BY-SA-2.0 (], via Wikimedia Commons
Until now none of these millenarian tree-planters seem have taken stock of what is happening to our native trees. In the whole of the twentieth century there were just five major outbreaks of tree diseases from imported pathogens, including, of course, Dutch elm disease. Yet, according to the Forestry Commission’s Tree Health Research Group in the past twelve years alone there have been more than double that number, all introduced by pathogens, especially fungi, coming from abroad. Some were given wide publicity, such as Sudden Oak Death (which, in Britain, has attacked larch more than oak) and the recent outbreak of a fatal fungal pathogen among our already beleaguered wild junipers. Others, like a new one attacking Scotland’s native pines, are little known. Yet it has taken until now for the penny to drop. Assuming it has dropped. I do not see any sign yet of a diminution in the enthusiasm for planting trees. The Woodland Trust is, as far as I can tell, still “passionate about tree planting”.

Meanwhile we are about to lose perhaps our most elegant, certainly the healthiest, native tree. The argument about whether tree planting was responsible will go on. The chorus of denial will be led by the zealots more committed to carry on planting than to admitting to any sense of responsibility for what has happened. And for what, at this rate, will continue to happen.

It is always harder to propose something that sounds positive than to propound a negative. But can I suggest that, until we can guarantee that nursery trees are free from contagious and fatal diseases we simply stop planting trees?


66 Replies to “Guest blog – Ashes to ashes – Peter Marren”

  1. Why in recent years has there been an increase in pathogens/fungi etc attacking trees. Is it due air quality/pollution/climate change or like some have said it’s been laying dorment for years? It’s interesting to note it’s just not the Woodland Trust planting these Ash trees. Any new road that has been built is lined with saplings, the same goes with some new housing developments.
    As for it crossing the English Channel naturally, what’s the current situation in Ireland?

    1. There has been a new tree disease caused by imported pathogens for almost every year of the 21st century so far (10). During the whole of the twentieth century there were just 5. The difference is that in the recent past, especially since the Millennium, there has been a large importation of native trees from abroad for planting. I will try and obtain exact figures from the FC.

      Ireland was prompter than the UK Government in banning imports of ash trees. No cases there yet as far as I know.

    2. According to the online Irish Times, there are confirmed outbreaks in the Irish Sea coastal county of Meath and the border counties of Leitrim and Monaghan. There are no reports from Northern Ireland or the Isle of Man so far.

      1. David – that’s quite a jump. Thank you for that news (not that it’s good news – but it is news). Watch out for birds getting the blame at some stage (as badgers are not known to swim that far). It’s probably the buzzards?

        1. My pal Mairead tells me that a single batch of imported Ash is suspected; she thinks from Denmark (!) but can’t recall for sure.

  2. From tree nurseries to wood yards! Dutch Elm disease was spread by the wood yards buying cheap elm from down country and allowing beetles to survive in cracks and crannies as the bark was stripped from clean areas of trunk. My first experience of the disease was working in ELM in Worcestershire burning big old hollow trees to the ground. Then while working in Cumbria the disease was found by a wood yard! Ash will do the same as wood yards in the south will not be able to cope with the many trunks available. One question to the guest – were Dutch ash seedlings cheaper than native ones?

    1. I think the common sense answer must be yes.

      The nub is that tree planters have been buying from GB nurseries without making sure that they were raised from GB stock and not from imports. I suspect it is not so much that ash from Dutch nurseries were cheaper (though no doubt they are) but that there isn’t capacity in GB for all the trees that the planters want.

  3. It is an enormous own goal and very sad that it is ostensibly due to the actions of people who love trees. The ban on importing ash saplings seems like shutting the stable door after the horse has bolted but we should also be looking at much stricter control on imports of all tree species (and garden plants). As Peter mentioned in the case of sudden oak die back, many of these pathogens are capable of infecting more than one tree species. We cannot afford to wait until the next tree disease arrives on our shores before we take action.
    Peter is right to question the view that all tree planting is necessarily a good thing but where we do decide it is useful and appropriate to plant trees we really must ensure we are planting suitable, healthy stock of whatever species we happen to have chosen.

  4. Perhaps one of the most ridiculous scenarios we have at the moment is the majority of groups, agencies and industry stating that import controls of stock should’ve happened years ago. This is truly rich when one of the worst culprits is the horticultural trade. Imports of plants, soils (and it’s largely peat so double whammy), and containers will almost certainly harbour pathogens which then enter this country; regulation is at best is weak and EU trade rules preclude against tough action.

    The next big worry is the potential for knee-jerk felling. Signs are that FC and others are very aware of this not least of all for veteran and ancient trees. There are even encouraging indications on the continent that a small number of ash are resistant to Chalara. Whilst the predications are grim we also need to be mindful that blanket felling didn’t work for elm and is unlikely to work for ash. The best chance the tree has is to ensure that a proper monitoring system is put in place and hope that the old and knarly trees have enough genetic diversity to carry at least some through.

  5. A curious answer to a devastating problem! To stop planting trees would be madness for many reasons. Private landowners, many of them intensive arable farmers feel that they are ‘doing their bit’ planting trees and hedges, these trees and hedges give much needed habitat to farmland and woodland birds and other taxa. Virtually any planting can increase the biodiversity of such areas. Britain’s motorway network which has come under fire from environmentalists for as long as I can remember is lined with tens of millions of trees ( a few of which I have planted!) These trees and shrubs provide habitat for a myriad of animals small and large and can act as a conduit for wildlife across otherwise barren countryside. The Woodland Trust and others have inspired more than one generation by getting children (and adults) to plant trees, this is the practical conservation work that Sir David Attenborough and Chris Packham brought to the headlines yesterday. The list of positives for tree planting goes on…….

    When Dutch Elm disease devastated the elm trees in the 70’s no one suggested we should stop using timber. Perhaps we should look to our plant health standards, perhaps we should give them more money, these guys are amazing scientists but with no teeth and no money. Perhaps we should stop exporting (UK provenance) ash seed to Central Europe and reimporting them as (possibly infected) trees to save a couple of pennies a tree. Maybe we should revitalise a grant system that produces such spikes in demand that there is a necessity to import the trees we haven’t grown.

    We must not stop planting trees!

    1. What about private landowners ‘doing their bit’ by just letting trees grow instead of cutting them down?

      1. Very often cutting trees down is ‘doing ones bit!’. For a very good explanation of woodland management principles see Mark Avery’s ‘Fighting for Birds’, he explains it very well!

        1. Mark (& Mark) – apologies for my over hasty reply. You’re right of course that tree removal is important in management of some habitat where the wrong trees are growing in the wrong place. But I would think this would apply in particularly rare, precious and threatened habitats. And yes sustainable woodland management such as coppicing is only to be greatly encouraged. However you appear to be talking about the farmed countryside. Your first example was of “intensive arable farmers [who] feel that they are ‘doing their bit’ planting trees and hedges, these trees and hedges give much needed habitat to farmland and woodland birds and other taxa.” Yet intensive arable farmers have been busily removing trees and grubbing out hedges for the last fifty years! Even those hedges that are left are often mutilated annually by hedge cutters, preventing any of the very large number of saplings which would happily grow into tall trees if they were left alone. A few saplings stuck in the ground is hardly going to compensate for this orgy of destruction, resulting in near catastrophic losses of exactly these birds and taxa you refer to.
          The example of motorway verges is a good one, yet how many trees here are planted and how many are self sown? Of these which are in the best health and best suited to their environment? The ready colonisation of land next to railway lines and former industrial sites are also a case in point.
          I sometimes wonder how on earth trees managed before we learnt to cut millions of them down, planted supposed replacements in random places where they would have grown anyway and started exporting lethal pathogens all round the world. In the case of Chalara I fear the answer is blowing in the wind…

          1. I do agree with you in principal! I have just passed miles of neatly clipped hedge on a local big estate, they should know better, what will the birds do for berries? Most landowners in Dorset who are our clients are fairly open to conservation centred ideas and are not the earth rapists that many conservationists think. I have spent the afternoon with a client who was after advice on thinning a recently planted woodland, he has followed the make up of another of his woods and it is 80% ash, it was rather difficult to give him the answer to his question.

            I think we should be looking at much tighter controls on plant movements not planting itself. I can’t pretend to be an interested casual observer as we plant up to 250,000 trees per year.

    2. I don’t disagree with anything in your first paragraph. But if the present situation continues – a new disease per year remember – there may not be many healthy trees left a few decades down the line. All that effort, all that money, and the result: less trees not more. Bit of an own goal, don’t you think?

      Remember the precautionary principle that every conservationist was going on about not long ago? If in doubt, don’t. All I’m suggesting is that it might be better not to plant trees if we don’t know whether or not they carry a contagious disease that may kill the whole lot. Sad for the kiddies I agree.

  6. In Powys there are several tree nurseries who grow trees only from local seed. They advertise together and produce friendly, healthy young trees. We trek into the lanes to a nursery to buy a few each winter as the local garden centres just seem to stock imported small standards. Could Local Authorities/ Woodland Trust grab this chance to promote availability of locally grown trees? The small growers might be able to invest in growing their stock to the popular larger sizes if they had security of demand?

    1. Security of demand is the key. It was thought that provenance (where the tree’s ancestors came from) was the key. This lead to seed from UK trees being grown across Europe and reimported once grown. This is highly illogical and would be seen to be illogical to all but people close to the issue! It is interesting that ‘your’ nurseries in Powys are denied the business to grow the trees to save say 10p on a small ash tree, surely these 10p’s will not equal the devastating bill for chalara, phytopthera et al……

  7. Peter is right, but why stop at tree saplings, if we want to constrain the rate at which new diseases and invasive species are coming into the UK then we must apply the same principles to pot plants and ban their importation.

    Its not just the diseases, a consignment of tree ferms from Australia impounded a few years ago contained 252 species of invertebrates, 50% of which had the potential to cause damage to horticulture, agriculture or biodiversity.

    I will be writing about an ash tree in the Guardian tomorrow –


  8. I feel fairly certain that ash dieback arrived here in south-east Kent on spores from across the channel rather than from horticultural imports which is probably why it is apparently spreading from east to west. The woodlands of France are just 21 miles away from Dover and Folkestone where dieback has been confirmed.

    I have spent much of my free time over the past 70 years wandering through woods here in Kent, Africa, South and North America, the Caribbean and mainland Europe. Woods are not static any more than we are. Periodically they are attacked by naturally occurring diseases as is all life on this earth but perhaps not on the scale of recent years.

    To judge by its extent it looks as if dieback has been present in south-east Kent for at least two years, but with one or two exceptions our woodlands are very mixed in this part of the country with hornbeam usually more prevalent than ash, so dieback could have been overlooked.

    It would be a mistake in my view to burn infected ash trees. Let them die naturally and keep an eye open for those showing some degree of immunity. We know the probable cause of the leaf infection in horse chestnuts which is an imported species – a leaf miner, a golden micro moth. Dutch elms are all clones and therefore very vulnerable. Ash trees increase sexually and will no doubt eventually survive dieback after the initial devastation.

    A variety of ash dieback has long be known in North America, recorded in Quebec and New York State in the 1920s and subsequently. It has killed many trees but there are areas where regeneration has occurred. Details of the North American incidences are on the web and very interesting.

    1. The spores might have blown over from France. But you have to remember the point of entry for most goods coming from Northern Europe are the ports at Kent, Suffolk and Essex so it can’t be ruled out to have arrived on imported trees.

  9. I am really encouraged to see that alternatives to blanket felling/burning are being considered.
    Personally, this whole thing has been devastating to me. My garden is surrounded by woodland that is almost all Ash, and my local patch includes an ancient ash wood where I did a heartbreaking stocktake and worked out that at least three quarters, probably more, of the mature trees on the reserve are Ash, including many, many ancient and veteran trees. And that is exactly what I’m fearing the most at the moment, that surely they can’t fell the whole wood if it’s found here? There are many rare species of moss, lichen, woodland plants and invertebrates that depend on those mature trees, and the shrubby understory combined with the few peripheral stands of Oak and Beech planted in the Victorian era will not compensate. If they fell the Ash, the whole wood would be destroyed. I have no experience in the field, but common sense tells me that surely it’s better to let the trees die off slowly and be replaced naturally, leaving the wood standing? And there’s just a chance that some of those old trees will survive, and given time even help regenerate the wood with their offspring.
    It may well be a simplistic view, but I have been somewhat suspicious of the need for quite so much mass planting for a long time just because any land left to itself re-trees itself naturally in a very few years anyway. And although I have always been an enthusiastic tree planter on a very small scale, every one I’ve ever planted, grown, given away, has been grown by me from collected native seed, or dug out of my own garden and bought on in pots. The idea of buying a native tree from a nursery would never occur to me, a bit like buying imported blackberries from a supermarket. The world is truely a mad place and yet again it’s our environment that suffers.

  10. At the weekend i had a look round a wood that was about 15 -20 years old with a nice section of Ash in good condition. 300- 400m away they had let a small area of field regenerate naturally and it was almost all an impenetrable stand of Ash seedlings up to 3 m high and it looked like most of the trees had disease. It was an amazing sight, if a little disconcerting. The older planting looked fine! This is the a few miles from the Suffolk coast and not far as the spore flies from the Woodland Trusts Pound Farm wood that they reported had the infection.
    I am afraid we have got it now and doubt if burning trees will help. Ash is such a prolific coloniser seedlings will be all over and some will be infected. Looking for resistance is surely the best policy now.
    I heard someone say you cannot ban something unless it is named on a restricted list which sounds lovely and Gilbert and Sullivan. If it is a disease you do not know! Just what mandarins would think up. To keep problems out you don’t let anything, but anything, in like the Australian model. But then we are not such an island
    Anyway so many things we do know and bring in go rampant. That’s the way we are going and it’s a brave new world coming. Parakeets on the peanuts and……

  11. I think that the nursery trade is being unfairly targeted here. Given that the pathogen is air born it may well have been impossible to avoid the disease and this is certainly the view taken by the Danish forestry service who have had this for some time. If there was blame attached to imports then Defra has to shoulder it as the agency who licensed imports not the nurseries and certainly not the Woodland Trust etc.

    From my own experiences in dealing with “imported” deseases in arable crops climate change is by far the greatest factor. I’ve been at a conference today dealing with Mycotoxins in wheat where the deseases profiles have changed out of all regognistion as our summers get drier and winters get wetter and warmer. I’m no expert in tree health but I’d be interested to know of this was a factor it all the recent outbreaks in Chestnuts, Junipers and now Ash ?

    1. The Americans have also been wondering about mycotoxins – have a look at their website on ash dieback.

  12. The best natural defence against diseases and pests is a broad genetic diversity.
    That is why it is best to try to use seed from native stock, and allow as much natural regeneration as possible. Trees best suited to the local environment (climate, soils, habitats, pest & diseases) are more likely to survive and thrive.

    The problem for us is that trees have a long generation time compared to humans. So a tree that grows for 25 years, but succumbs to a disease before it seeds profusely, may be showing ‘natural selection in action’ but we see it as a failure.

    Some Ash trees may already have some natural resistance to this disease, and these may re-populate the countryside quite quickly given how prolific ash can be & how effective it disperses its seeds. BUT, this may be quick in terms of ash generation times and not human.
    Elm was especially vulnerable to disease due to its habit of spreading primarily through clones, and not by seed, so its genetic diversity & ability to recombine its genes was low.

  13. Defra website reports a “summit” about Chalara today, and the results of a weekend survey of ash trees.

    The “top” ideas to tackle Chalara identified at the summit, include:
    • Better awareness raising and information gathering, such as on leaf litter management;
    • Keep surveying – develop partnerships to continue surveillance for disease and resistance and making use of volunteers; and
    • Focus action on newly planted trees – don’t cut down mature trees.

    A wide range of other ideas for action were identified, which will be examined in further detail. These and other ideas will now be considered for possible inclusion in a Chalara action plan to be published on Friday 9 November.

    Good info here:

    I hope the plan includes action to derogate any EU trading law which says we can’t stop all further imports of growing plants – from anywhere.

    Has anyone found an emerald ash borer yet?

    1. I would like to forget the ‘right’ name for the RSPB at the moment. I would like to respectfully request that the title of the next Mark Avery book should be ‘Fighting for Biodiversity’!

      Great blog, great comments.

  14. A fascinating debate and it is interesting to see the finger pointed at those who plant trees, many of whom were probably not aware of the issues around importing plants and could not reasonably be expected to? Surely that is why we have experts and a system of regulatory control?

    I stumbled across this reference while looking into the background to Chalara. Whatever your views on compensation may be, it seems that one of the major trade associations showed a degree of foresight and was campaigning in 2009 for Defra to halt imports of Ash, which has not hitherto been recognised on this blog. They deserve some credit for that. I would really like to know why this request was not acted upon sooner by Defra, when with the benefit of hindsight it has been blindingly obvious over a period of years that this devastating disease has been spreading out across Europe. I wrote to Defra a few days ago on this topic, and their reply did not cover that point. I have asked for clarification!

    Looking ahead, for me at least, the challenges are:
    • how best to manage the disease and its impacts in the short/medium term, and I guess that will include managing felling of live trees while the timber still has a commercial value,
    • Addressing the complex question of much better biosecurity measures. If nothing else I hope this serves as a wake-up call not just to regulators and environmentalists, but also to business. I wonder if the full socio-economic costs of dealing with the Chalara outbreak will exceed the value of the tree nursery imports? I don’t think it acceptable to put so much at risk because EU rules make it difficult to do anything about it.
    • What, if anything, we can/should do to support the other species that are wholly dependent on Ash such that they are able to recover.

    And finally, it may be worth speculating that this very dark cloud may have an unexpected silver lining. Perhaps we will see an increase in some of the very rare species that depend upon dead standing and fallen wood, another habitat that has now become very scarce!

    1. If the industry showed foresight in asking for a government ban on importing ash trees back in 2009 one could say that it also lacked restraint in not voluntarily imposing one on itself. Doesn’t that somewhat undermine its demands for compensation now?

      1. A good question Jonathon, and the answer is that I don’t know why voluntary restrictions weren’t imposed. However, I have just emailed the HTA to find out… The more interesting point perhaps is whether a Government-led ban on imports was reasonably foreseeable which would have allowed businesses to change their growing plans and avoid the risk completely. I have asked that too!

    2. Why is everyone so eager to believe that the fungus arrived as windblown spores from Europe? Isn’t it more likely they came from that cloud of spores hanging over the infected nursery or planted trees just down the road? There are more than sixty such sites now.

      As for letting the Woodland Trust (and others eg. the National Trust) off the hook, their publicly admitted ignorance is surely culpable. These people bought imported trees on a vast scale and apparently never once looked into their origin, and had apparently no knowledge of the risks of doing so. If they really are so stupid, these supposed experts, then this was a disaster waiting to happen. And more in the pipeline I fear. To the big four disasters to wildlife: climate change, pollution, habitat destruction and invasive species, I’d add a fifth. Morons.

      1. There is a world of difference between the big players like the WT and NT who have the resources and expertise to understand the issues and the myriad of smaller organisations like minor charities, community groups, landowners etc who do not and realistically never will. The latter group may also include other bigger organisations for whom tree planting is a part of their business but not at the core. If we assume that is true for a moment, then in many ways it really does not matter whether WT and NT are importing diseased trees or not as they will still be pouring into the country.

        The evidence suggests there has been a catastrophic failure over many years to adequately regulate and control the import of dangerous organisms. Your own earlier post says nearly one new tree disease per year during this century which is frankly staggering! On that basis it is hard to see what difference WT and NT would have made even if they had used home grown disease free trees. What we need is a strong and determined lead from the government to reduce the likelihood of similar problems continuing to happen through tough controls on imports. We are different from the rest of Europe in that we are an island, and our policies need to reflect that fact. Other countries like NZ manage it! Or am I missing the point somewhere?

      2. Is it more likely to have come from a cloud of spores hanging over a nursery or planted tree just down the road? The answer, I believe, is no. If that were the case it should be as common in the west of Britain as in the east which, apparently, it is not at present.

        That said, the horticultural industry has a lot to answer for, importing plants from various parts of the world without a proper quarantine period, and lazily having British seed grown on the continent rather than doing the job itself. Perhaps this will prove to be a wake-up call. How ever the spores got here, we need to be far more careful in future.

        I would not be too hard on the Woodland Trust, of which I am a member. Some years ago I criticised them for cutting grass on a botanically-rich site in Denge Woods, east Kent, and leaving it to decay on site, thus enriching the soil and diminishing the flora – but they learn and their overall intentions are, in my view, very good.

  15. The HTA raised the matter in 2009, when the Minister for Blame was Mr Bean.

    Links below are worth a read – the ascophyte stage of the fungus was at that time assumed (so I have read) to be Hymenoscyphus albidus, which was widespread in UK. It was later identified H. pseudoalbidus, which was “new”.

    If you are at work and pushed for time, you shouldn’t be reading this, but here are some significant words:

    situation, worrying, EPPO (the European and Mediterranean Plant Protection Organization), Pest Risk Analysis, decisions on controls, import and domestic movements, apparent, recently, disease caused by Chalara fraxinea, known as H. albidus, widespread across Europe, including Britain, precludes us, emergency response, EU Plant Health Directive, also fall foul, international obligations under the WTO, EPPO conclude, PRA is no longer relevant, our hands are tied.

    So there, in a nutshell, is the problem. Everything is in thrall to maintaining the flow of trade. As for behaviours – a voluntary ban on imports is a nice notion but to have any effect it has to have a very high uptake, and for the buyers and users of imports, the need for instant gratification may need revisiting.
    HTA letter to Forestry Commission – September 2009
    Forestry Commission response to HTA – October 2009

    1. Interesting post Filbert, which serves to confirm that the system is dysfunctional. Whatever happened to the precautionary principle?

      The HTA have replied to my earlier request with the following:
      Q. You will see that a subsequent question has been raised about why a voluntary ban on Ash imports was not called for by the HTA at the time. This is a relevant point, and I would be interested to hear your comments on that.

      A. Difficult to say with hindsight, but if the scientific position was that the disease was already established in the UK, a voluntary import ban by UK growers would in theory have served no purpose. And in any case, the end client would have imported directly from the continent. The disease is not controlled there and ash can be freely traded.

      Q. Secondly, with regard to compensation for growers, one could argue that it was reasonably foreseeable that a ban on Ash imports was probable at some point given what the HTA knew about the spread of this disease. Did the HTA give any advice to it’s members along those lines?

      A. Much as it is in the industry’s interests to maintain a healthy plant stock, the HTA is not the plant health authority. We highlighted our concerns to government, but the response based on scientific advice at the time was that the disease was already here.

      Q. I would also be interested to hear why compensation should be payable for a predictable event that would have allowed businesses that manages risk effectively to avoid financial loss.

      A. Some UK nurseries have already incurred significant costs through destruction orders. If, as we fear, the disease is already widespread and established in the UK, this expense could prove to be completely nugatory. Furthermore, no destruction orders have been served in other EU states. So our growers’ ability to compete, and even survive, is being eroded through actions that may solve nothing. One could argue that this is an unnecessary yet imposed cost that should in fact be met by government. As it is for animal disease.

      In terms of loss of earnings, the complete ash crop has effectively been declared redundant through a disease about which we warned three years ago but were told that it was already here. If you sought professional advice that proved to be incorrect, would you not seek redress from that provider? Furthermore, with the constant emergence of new pests and disease, why would anybody consider growing trees and plants as a business? The answer, like for any industry, is that our growers are supplying market demand. So where does the business risk lie? With our growers, or with the forest grant schemes and amenity projects who specify market requirements? It is a complicated area.
      My thanks to the HTA for the very quick response!

  16. I would like to add three very different points to this discussion, if I may:

    1) On Nov 4th the Forestry Commission posted a map on their website which included a number of blue dots, clearly indicating Nursery sites at which infection had been confirmed. There were 13 in total from the far north of Scotland to the SW of England. Can anyone suggest why FC should no longer be displaying that data now?

    2) The HTA’s website not only shows the 2009 letter they sent to the Forestry Commission, but also the FC response they got back. The last sentence of that second letter is worth repeating, and one wonders how much the Horticultural Trades Association acted upon it: “All I can recommend for the moment is that the industry carefully
    considers where it sources its planting material and monitors its purchases for signs of
    ill health. Yours etc . . .””

    3) My most important point is to suggest that now seems to be the ideal time for the major conservation and landowning organisations to join forces to call upon every UK farmer and landowner to act now to better manage the country’s hedgerows. If we could ride on the tide of popular alarm at the future loss of all our ash trees in the landscape, we might just be able to persuade some of those land-managers not to embark on their annual short-back-and-sides treatment of every hedgerow they can see. In many places I know of in Derbyshire there are no hawthorn flowers in spring, no berries in autumn, and no emerging trees coming up to replace the now ageing populations of hedgerows trees that are simply too ancient and massive oaks and ashes to flail into submission. Chalara will eventually do that for the latter.

    Just look at the photo at the top of Mark’s blog and imagine the farmed landscape without that single ash tree. I think we need to start now to talk about how we replace the loss of hedgerow ashes. Yes, we will need new trees to be planted, but we also need to engender a sense of responsibility for replacing our British hedgerow trees amongst those who believe that their management ways are the right ones. They are clearly not.

  17. Almost exactly a year ago Dr. Webber (Principal Pathologist at Forest Research in the FC) gave a free public talk at Birkbeck College on Pests and Pathogens of Woodland and one of the major take-home points she made was that the growing penchant for “instant” landscaping by planting already grown trees was making the inspection process a lot more difficult than it had been in the past. It’s difficult to inspect the entire plant when it’s large and the shipment being inspected may not be homogeneous anyway. It’s an almost impossible task to police properly, carries great risks with it and it’s all done for convenience’s sake rather than necessity. I have a hard time figuring out how it can be reasonably justified.

    The slides from the talk can be found here if anyone’s interested:

  18. “… growing penchant for instant landscaping …”

    “Fetish” might be more appropriate. Local authority planners should take note.

    Or be locked in a room and made to listen to a tape loop of James Merryweather’s “Gardening the Countryside” until they get it.

  19. Why oh why does man feel so compelled to meddle?

    There is always a good reason for humans to do things just because we can, the truth is that we do too much! We always have done! Carving out our niche instead of fitting into one which already existed. Ash trees might pull through, they might not! Humans will carry on trying to find ways to put things right after they have gone wrong! It’s inevitable because the human population is reaching breaking point but we are so well protected by our own invention that the effect is felt in our environment and the species that share it with us – always as a byproduct of our meddling.

  20. Maybe land managers who want to plant hedges should be encouraged to take saplings from local woodlands and use them instead of buying stock from nurseries

    1. The BSBI advice is, unfortunately, not that sensible; it appears to take an overly narrow take on the matter and even appears to be somewhat blase in its approach. Ash is an important species for many epiphytes. It plays a crucial role for many lichen species and communities in a range of woodland types as well as other habitats such as parklands. Any significant loss of Ash could have serious consequences for the lichens associated with them.

  21. Fantastic blog and comments, and i wholeheartedly agree with Peter Marren. Please stop ‘conservation’ tree-planting.
    Oliver Rackham in Woodlands (2006) warned that due to the globalisation of plant pathogens ‘Tree-planting practice, as now organised, is probably the greatest long-term threat to existing woodland’.
    Despite the undoubted symbolism of planting a tree or new ‘woods’, we must learn that the benefit is merely to us, and is no substitute for the ancient woods we have lost, especially when these new ‘woods’ are on ex-farrmland that will never display the wildflowers advertised on the brochure. Too much ancient semi-natural woodland (ASNW) lies unmanaged and shady with worrying declines of open space species, yet the creation of new ‘woods’, (plantations by any other name) continues unabated.
    Plantlife’s recent report highlighted that ‘More woodland is a well intentioned aim but what we really need is better woodland’.
    One can only hope there is no knee-jerk response to this crisis, and though the loss of veteran pollard and coppice stools will be an irreplacable loss of living history, within the wider ancient woods we can only hope that there is some natural immunity and that natural regeneration is allowed to colonise the gaps. No more planting please. As Plantlife once again highlight, ‘We need to put less emphasis on the quantity of woodland but focus instead on the quality’.
    There are no woodland species declining due to a lack of trees, but as in the Locust Years of the 1950s and 1960s the economics of tree-planting are yet again threatening the woods.

  22. “Too much ancient semi-natural woodland (ASNW) lies unmanaged and shady with worrying declines of open space species, yet the creation of new ‘woods’, (plantations by any other name) continues unabated.”

    It seems from the first part of this sentence that there is an automatic supposition that woodland should be managed. There does seem to be an understanding in British ecology: whatever you do don’t just leave it to nature, or you’ll lose species which people arbitrarily like.

  23. As someone who, for nearly thirty years, has been helping to conserve (via traditional coppicing and natural regeneration) an ancient woodland nature reserve dominated by Wych Elm and Ash, (and with a lifelong passion and concern for wild, ancient and historic trees, landscapes and all other flora and fauna), this new Ash Dieback crisis has come as a huge psychological blow and shock to the system. Never did I once think that such a phenomenon would arise to remove so much hope for the future for native trees and wildlife in the British landscape, potentially on a scale far, far worse than the total catastrophe of Dutch Elm Disease. Nor did I ever think that it would be the `false conservation’ practice of mass tree-planting that would bring this disaster about.

    However, despite the gloomy prognosis, there are a number of really serious questions about the biology and ecology of this disease (and the way it is being reported) that very few people seem to be asking, and which may provide a glimmer of hope for the historic treescapes of Britain.

    For example, is this mainly a disease just of woodland? Or only of artificial plantations? Most of the media reporting (and the very few photos and films) only seem to refer to `woodland’, but the Danish and Continental cases often appear to be plantations within larger blocks of intensive forestry areas (see also Google Earth). The Ash population within the British landscape doesn’t seem to be anything like those of Denmark or Poland – will this disease have the same effects in non-woodland situations or hedgerows (where there is often less damp leaf-litter for the fungus to produce spores). How can spores ever settle on the leaves of exposed trees? How can small whips or saplings produce enough spore-laden leaves to infect wider areas? Where does the fungus overwinter? Are insects involved in its spread? (a distribution map of the Harlequin Ladybird invasion a few years ago looks amazingly similar to the general pattern of confirmed Ash Dieback sites in East Anglia and Kent!!).

    The answers to some of these questions (and many others) could have profound effects on how the disease spreads, how it might be controlled and what damage it might cause – will there really be nearly (an almost incomprehendable) 100% tree loss in the farmed landscapes of parts of the Midlands such as South Leicestershire and Northamptonshire?

    Long ago in my youth it became clearly apparent that (with a few exceptions) tree-planting was not really of much benefit to the actual conservation of native trees themselves – guided by the great writings of people like Oliver Rackham, George Peterken, Richard Mabey and Peter Marren, combined with observing what actually happens in the real landscape all around us (and physically managing ancient coppiced woodland on an almost daily basis!), it was and remains quite clear that allowing trees (and other plants/habitats) to naturally regenerate is the only way to really ensure that they retain their biological diversity and adaptation to local conditions over time. Basic principles of conservation seem to have been forgotten (if they have ever been taught at all?), namely those of sustainability, continuity and self-renewal (e.g. as set out by Richard Mabey in `Common Ground’). As a general guideline, species should surely be allowed to remain `wild’, and largely look after themselves in the landscape, living and growing alongside or as part of how humans physically use them as a valuable, renewable resource – sustainable harvesting of natural regrowth (without adding anything biological, chemical or physical that is not already part of the ecosystem) has surely been the way throughout history that humans have adapted, maintained and made use of so many of our semi-natural habitats, such as ancient woodland, hedgerows, meadows, pastures, heathlands etc.

    Once any type of `cultivation’ comes into play, whether it be of trees, crops or garden plants, this inevitably leads to a great reduction in biological or genetic diversity, as humans will select only a few visible traits seemingly of value and easy to manage or replicate at the time, but maybe not in the long term interest of the gene pool required to keep a species evolving through changing circumstances over much longer periods.

    I have great concerns that some of the `solutions’ to this present crisis may cause further problems in the longer term – the idea of searching for and selecting resistant Ash trees for re-planting seems sensible, but, so as not to reduce genetic variety even further, it would surely be much better to allow this to naturally occur via self-seeding from surviving trees? The scale, structure and location of the wild Ash tree population in Britain is so vast, (including many thousands or millions of ancient woodland and hedgerow coppice stools, ancient pollards, youthful, mature and veteran trees, self-sown saplings, garden and parkland specimens etc., etc.) that no artificial plantings could ever hope to replace it. There might also be a clamour for the widespread planting of new `replacement’ trees – but what species has similar and robust qualities to survive as a wild tree in the general modern landscape? (Sycamore?!)

    I believe that the current control measures put in place may well help to prevent or slow the spread of this disease – if infected trees and saplings are removed and burnt then surely this will greatly reduce the amount of spore-producing material? As with Dutch Elm Disease, a fuller understanding of the life cycle of Ash Dieback could well help to control it – elm disease is controllable to an extent by ‘sanitation’ felling of diseased trees or saplings before bark-beetles and the fungus can breed in them. However, Ash Dieback may be very different in behaviour if randomly wind-borne, and especially because it apparently attacks younger shoots and saplings (the Elms have not all `gone’ as widely stated – as well as a scattering of mature survivors, imost remained alive at their roots and remain as an abundant component of the landscape, though now in a reduced form, clearly having evolved to survive the disease in this way).

    Anyway, apologies for this long ramble (good to hear Peter Marren, Oliver Rackham on Radio 4’s Saving Species today) – I only hope that some changes in attitudes and mindsets may arise out of this crisis and that the Ash tree will survive as a major component of the historic British landscape.

  24. I have only just joined this discussion, so forgive me if I mention anything that has already been covered.

    I am interested in the tree planting v. natural regeneration debate. Where I live in East Sussex there are many small woods that have arisen quickly and naturally on abandoned fields and similar places. I have studied one square metre of ground in my garden very closely for ten years and birch, sallow, ash, oak, hawthorn, sycamore, hazel, hornbeam and holly have all appeared naturally from seed. Conservation organisations and local authorities could just buy fields and abandon them as nature reserves, though I do agree we have to keep an appropriate quantity of heath and glade and grassland, spaces that BHA (Before Human Arrival) would have been created by herbivore grazing, wind throw, fire etc.

    It seems to me that the passion for tree planting, if not purely commercial or wanting a slightly quicker result, has what I suspect is a somewhat hidden agenda that has nothing or little to do with conservation. It is an economic thing, the movement of goods and services, the flow of money. Young trees for planting have to be sold and bought, this creates employment, often in areas where there are few other economic opportunities. Many others benefit from tree planting: makers of machinery and equipment and Tuley tubes, carriers who ferry the plants to and fro etc. I am sure organisations that generate such economic activity are smiled on at government level and can more easily win fapproval from people in high places. Leaving a field or road embankment to develop naturally under a minimum intervention or non-intervention regime generates no economic activity, no flow of cash and no employment and is therefore never likely to be significantly encouraged, I suspect, by the powers-that-be (whoever they are).

    On a slightly different point, the European Plant Protection Organisation (EPPO), of which the UK is a member, raised the alert on ash dieback disease in 2007, but no one seems to have noticed in this country. If this information had been widely circulated in the nursery trade at least some of the businesses involved could have avoided the disaster of importing diseased trees.

    Finally, the matter of wind borne spores is very graphically illustrated by a short film from Austria of clouds of spores billowing from Hymenoscyphus pseudoalbidus fruiting bodies growing on ash twigs and petioles. See here:

    Cutting ash trees down, which now does not seem to be encouraged, is clearly aiming at the wrong target. Indeed, as the tree falls to the ground, I can imagine spores floating away like smoke in an infectious cloud.

  25. Therein lies the rub Patrick “**Nor did I ever think** that it would be the `false conservation’ practice of mass tree-planting that would bring this disaster about.”

    The ‘law’ of unintended consequences in action, yet again…
    As Patrick correctly notes, EPPO have had this disease flagged up for several years; so why did the UK government apparently take so long to notice this potential disaster?

    This disease would probably have reached the UK sooner or later, it just happens that, this time, it’s sooner.

    Why? Well, ‘stuff’ is moved around over huge distances and with greater speed than ever before and, with the advent of e.g. so much air-travel and rapid shipping, etc. it really shouldn’t surprise anybody that the UK is under attack from a wide variety of pestiferous species, from plant pathogens, animal diseases, through invert’s and vertebrates.

    The project I’m working on has several datasheets titled “Pathways”, and it’s these pathways (biological audit-trails, if you like) which have radically ‘enhanced’ the transmission of invasive species.

    Even tsunami debris floating across the oceans is implicated.

    Who’s next; no idea, there’s a long list – but Emerald Ash-borer (currently decimating Ash in the USA and now around Moscow) had better be quick, else there will be nothing left for it to bore! ;-(

    What is certain is that, without adequate quarantine measures in the UK, many more disasters could occur…. maybe it’ll be Japanese oak wilt or Korean oak wilt next…

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