d People & Behaviour


By far the most interesting part of the discussion, and perhaps the more optimistic, was identifying how we might rise to the challenge of making our precious trees and woods more resilient in the face of these on going and inevitable threats. With the input of renowned woodland ecologist, Keith Kirby from University of Oxford, the group considered how the natural and cultural history of our woods has shaped them – and what we can do to give nature a helping hand.

This cannot be a ‘one size fits all’ approach and there is no simple template that all woodland owners and managers should follow – in fact the tendency to try and manage all of our woods in the same way in the past or previous suddenly shifts in management resulting from pursuit of narrow theories has probably made them more vulnerable today. A vulnerability compounded by the continuing gradual loss of woodland and the fragmentation of woods and other habitats, leaving them disconnected and isolated.

But some key principles are emerging. Our woods will be more resilient if they contain a wider range of native species, and have a more diverse structure too – so that we have a good mix of types of trees and a range of young, established and older trees.

Prof Erik Kjaer from the University of Copenhagen, confirmed that a small proportion (around 2%) of ash may be naturally resistant or tolerant to chalara. There are also good signs that this characteristic can be passed on to progeny of those surviving trees.

http://wtcampaigns.wordpress.com/2013/06/28/making-our-woods-more-resilient-tapping-in-to-the-insight-of-experts/

See what we are doing: The Natural Ash Nursery –

http://worldwidewood.wordpress.com/2013/06/17/natural-ash-nursery-cleared-and-ready-for-the-deer-fence/

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Dutch elm disease is a tragic thing to watch, but we shouldn’t be too gloomy. Woody vegetation responds, adapts, regroups. What emerges in its recovery stage may not be the same as before, but it will always be a vital, dynamic, arboreal community.

The fungus, now known as Chalara fraxinea, is biologically mysterious, an entirely new organism of uncertain origins. It probably evolved in eastern Asia, where it appears to be harmless to native ash species. Its ancestor is a benign and widespread leaf fungus called Hymeno­scyphus albidus, native even in the UK. But at some recent date, this threw up a mutant, Hymenoscyphus pseudoalbidus, with slight genetic differences but a terrible virulence.

Natural resistance is likely to be the best hope for the survival of a core population of ashes in the UK. Isolated from the continent for nearly 8,000 years, our trees may be more genetically diverse than those in Poland.

For their part, ordinary rural people were mystified by the need for plantations, having lived for thousands of years with woods that renewed themselves spontaneously and indefinitely by seeding, or by regrowth from cut coppice stools and pollards. In place of this system of natural regeneration came the notion of trees as artefacts, biddable machines for the production of timber, programmed at every stage of their lives from planting to cutting.

The fundamental grammar of our relationship with them had been changed. Previously, “growing” had been an intransitive verb in the language of woods. Trees grew, and we, in a kind of subordinate clause, took things from them. In the forest-speak of the Enlightenment, “growing” became a transitive verb. We were the subject and trees the object. We were the cause of their existence in particular places on the earth.

Now, in the extremities of ash dieback, we can see that decades of well-intentioned planting have been not only often unnecessary, but, quite possibly, dangerous. Runtish saplings, often mislabelled and of unknown provenance, are shoved into the ground, regardless of whether they might be vectors for disease, or whether the soil is right and the site appropriate.

The existence of a large population of indigenous ashes is our best safeguard for the future and makes rather baffling the Forestry Commission’s experiment, initiated early in May, of planting out trial plots with 150,000 saplings of “15 different varieties”. The intention is to discover whether a few may be resistant and eventually propagate from them. But as 80 million ashes from probably ten times that number of genotypes are already engaged in just such an experiment across Britain, it is hard to see this as much more than a PR exercise – one that fits tidily in to our long, hubristic belief that the salvation of trees lies with us and our superior arboreal intelligence only.

http://www.newstatesman.com/sci-tech/2013/06/our-ash-trees-are-dying-dont-despair-catastrophes-are-natural-events-lives-trees

See also: http://worldwidewood.wordpress.com/2013/06/17/natural-ash-nursery-cleared-and-ready-for-the-deer-fence/

I am particularly excited that the Real Life Science Studio in the John Hope Gateway will be hosting the Virtual Landscape Theatre for one week from 8th August. This interactive exhibit allows an audience to decide what actions should be taken to reduce the impact of ash dieback and to explore the implications of these choices. Intrigued? Come and find out more in August!

Diseases are a real threat to our trees and it is likely we will loose a high proportion of our ash trees. Yet, over the course of this project I started to feel more positive about the future of Scottish woodlands. It would be easy to listen to the mass media and get very depressed about the state of our forests and trees. But woodlands are dynamic and have always changed; over such long periods of time we humans find it difficult to comprehend.

We need to build resilience in the woodlands of Scotland to ensure their longevity. By this I mean managing woodlands in a way that creates diversity in the species present, diversity in the age of the trees and diversity in structure. If we do this it may be possible to maintain the ever-changing, unique woodlands of Scotland.

http://stories.rbge.org.uk/archives/2051

This year, the winter’s work graduated from the young hazel coupes to the high forest. The objective was to fell 85 per cent of the trees, leaving only the very best oak trees, about 20 of the best ash and a few lucky birch trees to add a bit of variety. Of course, all the dastardly Holly had to be removed, too.

In two years, a crop of thousands of ash seedlings will sprout into the new light. Then all we have to do is keep the Holly regrowth in check and KEEP THE DEER OUT with a fence. The experts are saying that one in 10 trees are resistant. Lets say I have 10,000 seedlings … we would still have too many ash trees for the area. So let’s say, it is only one in a 1000 that are resistant, then we would still have 10 resistant trees, wouldn’t we? And that would be priceless.

http://worldwidewood.wordpress.com/2013/04/25/ashes-from-ashes-making-a-one-acre-natural-nursary/

The majority of forest volume in the UK is not publicly owned – out of a total forest area of 3 million hectares in the UK, only 28% is managed by the Forestry Commission. For ash, this figure is much lower, with only 3% of ash woodlands not owned by the private sector.

For private owners, the costs of surveying, felling, and replacing ash trees are likely to be high, and the effects of this could be long-lasting. An increase in the amount of timber in the market could also drive prices down, affecting landowners even further.

For landowners to engage in monitoring ash dieback, resources must also be available for them to do so. The number of inquiries sent to the Forestry Commission’s Tree Health Diagnostic and Advisory Service has increased by 1000% over the past six months. As diseased trees come into leaf over spring, and more trees become infected when the Chalara fungus sporulates again in summer, this high workload could even increase.

The number of tree diseases present in the UK has risen exponentially over the past 20 years, and now, almost all tree species are under threat from at least one disease or pest. Red band needle blight and ash dieback threaten up to 18% of woodland in the UK.

The report compiled by Confor highlights that the extent of private ownership of ash woodlands needs to be taken in to account.

http://britishecologicalsociety.org/blog/blog/2013/03/15/assessing-the-impacts-of-ash-dieback/?utm_source=twitterfeed&utm_medium=twitter&utm_campaign=Feed%3A+EcologicalAndPolicyBlog+%28BES+Ecology+%26+Policy+Blog%29

Forestry officials have confirmed the Chalara fraxinea fungus, which causes ash trees to gradually wither and die, has been found at three new sites in young trees in Wales.

The cases are the first to be identified since the start of the winter, as the symptoms of the disease, which threatens to devastate Britain’s 80 million ash trees, become hard to spot in trees once they lose their leaves.

The number of cases to be found in Britain stands at 386 since it was first discovered last February, with 170 of these in mature established woodland.

All the trees at the three sites, which had been supplied by a nursery previously found to be infected with the fungus, were destroyed. Testing has suggested around 10 per cent of ash tree sites are infected.

Scientists have also found that infected trees were being imported into Britain from elsewhere in Europe as early as 2008 – far earlier than believed previously.

“In the case of Chalara, it’s very important to make sure you don’t inadvertently move ash leaves, living or dead, around the countryside.”

http://www.telegraph.co.uk/earth/environment/9904591/Ash-dieback-found-in-three-new-sites-in-first-infections-of-the-year.html

 

In East Sussex where I live I know of many places, usually abandoned fields, that have regenerated to secondary woodland surprisingly quickly and, judging by the size of the saplings I have seen in some televised tree planting schemes (maybe only from seed this year), regeneration may be almost as fast, if not faster than planting.  Though it does not do much for the tree nursery trade, or other human engagement with tree planting schemes.

I have long thought that we are failing to appreciate the diversity and complexity of wildlife if we compartmentalise the landscape too much: that is a wood, that is a heath, that is a field.

http://ramblingsofanaturalist.blogspot.co.uk/2012/11/the-ash-dieback-debate-develops.html

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