Shocking declines in large old trees worldwide

Research from Spain and Sweden in Europe, Brazil, Australia, California and many other parts of the world, provides grim evidence of massive declines of some of the largest organisms on earth – old trees (Lindenmayer et all, Science vol 338 7 December 2012). If populations continue to collapse, as predicted, with them will also disappear the ecological, historic and landscape roles of these keystone structures that cannot be provided by younger trees. John Muir, founding figure of the conservation movement in the USA and a passionate advocate for the giant redwoods of Yosemite National Park (population decline of 24% between the 1930s and 1990s) is no doubt turning in his grave.

Image: WTPL

Why are large old trees disappearing?

Why are large old trees disappearing? As individual trees they are exceptionally vulnerable to a wide range of impacts – intentional removal, new pests and diseases, root compaction and damage, fire and competition – to name a few of the major culprits. However the biggest danger is that the loss is iterative and cumulative – one tree here, another there, so it is remarkably difficult to see the overall picture until very late in the day. Humanity is only just waking up to how valuable they are and putting them in the same category as tigers and whales.

The UK is seriously affected too. Devastating outbreaks of new diseases and pests are threatening large old trees in our own backyard. Where once we could boast that our heritage of ancient and veteran trees was perhaps second to none in northern Europe, the situation is changing fast. The latest threat to our large old trees comes from ash dieback but there is a number of emerging tree diseases which have the potential to become epidemics, resulting in further drastic loss of ancient and other special trees.

The Woodland Trust has a three point plan to ensure that the risks are kept to the minimum. While it appears that we cannot stop the rampage of ash dieback we might be able to find resistant trees among the ancient and veteran trees on the Ancient Tree Hunt database. Carry on recording important ash trees and monitor their progress by adding comments to the record blog and uploading an image annually. Through the database we may then be able to identify those trees which are surviving and those that are succumbing. Either way we will be capturing a landscape that we could lose temporarily, enabling us to repopulate it in future with resistant ash or other species of tree.

Jill Butler, Conservation Adviser (Ancient Trees)


About Kaye Brennan

Trying vegan, staying warm. Occasional bursts of words.
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26 Responses to Shocking declines in large old trees worldwide

  1. Tree Pruning says:

    We can do plenty about the climate change, but only when it becomes more important to the people to live then it is to chase the dollar bill.

    -Samudaworth Tree Service

  2. Thanks Pip for your comments. I would be interested in your evidence that huge numbers of mature oaks are being harvested for wood fuel – is this your personal experience or are you obtaining it from an official source? Fortunately the UK Woodland Assurance Scheme has a number of safeguards for sustainable management for biodiversity and for a management scheme to be grant aided the owner has to be signed up to it. Some owners may not have joined the Scheme as it is voluntary, however we must hope that in approving felling licences in these situations the Forestry Commission considers sustainability quite carefully. It is trees in the wider landscape and in towns that are much more vulnerable and have no one to look out for them. I agree that citizens need to be much more environmentally aware and participate in the Ancient Tree Hunt recording scheme to put their important trees on the map and become Tree Wardens to work closely with their Local Authority to monitor them.

    • Pip Pountney says:

      It is positive that groups are forming all over the country which care for urban trees and take responsibility for them through tree warden schemes etc. Also, the Ancient Tree hunt has strengthened public awareness and interest in the importance of our older tree stock.
      Much more worrying is the trend towards sustainable management of our woodlands and the threat to older trees within them. Locally, people became concerned when around 30 oaks in an SSSI ancient oakwood 200-300 years old were felled, chopped up and sold very lucratively as firewood for wood burners. Enquiries led to the local Wildlife Trust who own the wood and then to the Forestry Commission who had agreed to the felling and apparently provided funding for the programme. A huge number of mature oaks are now earmarked for felling over the next four years – all with the approval of FC who assured us that taking hardwood from our woodlands is a fine idea and that people will just have to get used to the sound of chainsaws! I am very afraid that what we are seeing is an excellent money making opportunity dressed up as woodland management and possibly all felling programmes should be carefully monitored through discussion with qualified and experienced ecologists. Perhaps the context of the word ‘sustainable’ needs to be reviewed?
      If thinning is required then this should involve removing as few mature trees as possible and these should be left on site to provide deadwod habitats.
      There are many woodlands in this area that have received management programmes involving the removal of large numbers of mature trees. During the following years we have observed a total loss of anemones in one ancient wood and in others a marked reduction in bluebells. We have noticed that if management is not maintained then non native species such as rhododendron fills up all available space and flourishes in the extra available light.
      As many of our woodlands and forests are publicly owned shouldn’t we be asking for full information and consultation before woodland management programmes are approved?

      • Hi Pip, the Woodland Trust is all for truly sustainable management of woods, where this delivers biodiversity benefits or at the very least no negative biodiversity impacts. Requirements for sustainable forestry are set out in certification schemes like UKWAS for those who are using them, and in the UK Forestry Standard guidelines, which does include wording on deadwood and veteran and ancient trees. There may not however be adequate monitoring of whether people are meeting these requirements in their management (it would be a condition of any grant or felling licence) – although should be picked up by the scheme auditors. Did you know that as part of the scheme anyone can lodge comments at the 5 year review period or at any time and in my experience the auditors take this very seriously. The Woodland Trust does believe that ancient woodland needs to managed sensitively – you can see what the Woodland Trust thinks in “Ancient Woods: A guide for woodland owners and managers”
        ( which particularly mentions ancient and veteran trees as important features to be taken into account in management planning.

  3. Pip Pountney says:

    Mangement of older trees in our urban landscape, woodland and countryside needs careful monitoring. An effort to restore natural native woodland by removing conifer plantations planted in the last century by Forestry Commission should be effective but in fact has highlighted that our mature oak trees are a valuable and sought after resource. The word ‘sustainable’ in a forest/woodland context is giving the green light not only for the rapid removal of non native conifers for timber but also the destruction of our hardwood trees as fuel for wood burners etc. Wodland management schemes are seeing huge numbers of mature oaks removed for this purpose. All are carried out under the umbrella of effective woodland management but in fact the oak trees chosen to remain are often not the ones that natural selection would ensure lived for their full 1000 years. Some woodlands that have received this treatment have many strangely shaped poor specimens that stand isolated and are later brought down by adverse weather conditions.

    Ancient trees in our towns and cities are also under constant threat through health and safety concerns and development. Some of the reasons given for their removal are extraordinary – ‘Wrongly placed’ and ‘Over mature’ among them. Firms contracted for their removal are often very aware of market value. People in towns and cities could perhaps try to maintain regular contact with tree officers and councillors to demand that tree stock is correctly cared for and protected.

    Ecologists are quite clear that woodlands evolve naturally and that you cannot revert to a previous time through extreme management methods. Our ancient trees take centuries to grow and yet can be removed in a single day. Perhaps we need to slow down, removing a few non native trees each year and allowing our forests and woodlands to regenerate naturally. Maybe funding and effort should be directed towards extending, linking or complementing existing fragmented woodland by establishing coppiced zones where previously they did not exist. These then could provide a slow growing but ethically sound and truly sustainable source of timber.

  4. strider712 says:

    Reblogged this on bobsrantsandraves and commented:
    I am not sure what humankind can do to meet this challange.

    • Old trees are lost often as individuals but cumulatively across the world this adds up to the equivalent of forests. Each and every one should be considered precious and only cut where there is sustainability of the values it represents present in the environment to continue their value into the future.

    • Kaye Brennan says:

      Thanks a lot for re-blogging Bob 🙂

  5. mottledthrush says:

    Reblogged this on MottledThrush and commented:
    So sad. The depletion of trees worldwide is extremely concerning – people need to wake up to the importance of ecology.

    • Thanks very much for sharing with others – the depletion of old trees is extremely worrying – they are at the height of their working lives. If we cut them down we need to wait for a tree to grow to the same size to provide the same benefits and that takes centuries!

    • Kaye Brennan says:

      Thanks for re-blogging! Another new blog friend to follow 🙂

  6. Julie Taylor says:

    Thank you Jill/Kaye for highlighting this issue again.
    In various campaign emails etc over the past year or so I have found myself repeating the same thing. I certainly feel ancient trees should be regarded as ancient monuments. If people were proposing demolishing that old statue in Trafalgar Square or perhaps that old stone pillar with some woman stuck on the top in the sea near New York I am sure we’d hear plenty of voices raised in defence of them. … not that I am proposing such monuments should be demolished, you understand 🙂 Our ancient trees deserve better.

    • I couldn’t agree more that while all trees are equal some are more equal than others and ancient trees are not that common that they should ever be taken for granted. Thanks for all your support!

  7. argylesock says:

    Great post! Reblogged to Science on the Land.

  8. dollytubb says:

    Reblogged this on Wood Elf Weekly and commented:
    Ancient trees are worth their weight in gold and jewels for the sheer biodiversity that they support. Watch out for a blog post on Ancient Trees in the New year

  9. Alex Jones says:

    The greatest killer of ancient trees is climate change, which I sadly admit we can do nothing about.

    • Climate change and globalisation are very big threats but there are many other impacts that are also leading to loss of important trees in the UK – impacts that we could do something about if we had the will to do so. One of the biggest in the UK and the world is the intensification of agriculture and forestry – if we could protect trees in our countryside then they would continue to pay us back every moment of their working lives in carbon sequestration, soil fertility, flood alleviation and beauty as well as all the other usual tree benefits.

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