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

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  • Developing resistance to the disease in the native ash tree population
  • Encouraging landowner, citizen and industry engagement in surveillance, monitoring and action in tackling the problem

Defra said it is planting 250,000 ash saplings in the east and south east so Defra scientists and the Forestry Commission and local landowners can monitor the trees for signs of Chalara, paying particular attention to any signs of resistance.

http://www.trees.org.uk/aa/news/Defra-admits-impossible-to-eradicate-ash-dieback-148.html

Comment: It is crazy to spend all the money planting out nursery reared seedlings, when natural woodlands can do a much better job themselves for free, with woodland saplings benefiting from their ancient mycorrhizal support systems. See: http://worldwidewood.wordpress.com/2013/04/25/ashes-from-ashes-making-a-one-acre-natural-nursary/ (JW)

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

Should we start planting Ash with natural Chalara resistance even if they aren’t of UK provenance, e.g. Danish ‘Tree 35′?

AD: We should be very clear that tree 35 is not ‘resistant’. It tolerates the fungus better than most but it still gets infected. We do not know what is likely to happen with such trees over 20-40 years. The plan it to see if there are different genetic determinants in different trees that tolerate the fungus. If there are, it may be possible to cross them with each other and combine the characters to increase tolerance.

DM: It isn’t certain whether ‘Tree 35′ is going to be tolerant against the UK population of ash dieback. Tree 35 has shown to have great tolerance, but it isn’t clear how it will be in 20 – 30 years and we want to be able to create long term resistance. That said, there are great lessons to be learned from the genetic makeup of this tree and understanding how it has reached this tolerance is going to be of great benefit. In the end we would like to achieve a UK population of resistant trees, with UK-specific diversity, as our tree population is genetically different from the Danish population.

JW: Before we can go ahead with widespread planting of ash trees such as Tree 35, we have to be sure about the extent of its resistance.  However, just because trees/seeds are not of UK provenance doesn’t mean we should exclude them.  The releases from a number of programmes breeding for resistance to Dutch elm disease have made use of a wide range of elm species from Asia to produce resistant elms.  Also, many of the broadleaf trees planted in Britain, including oaks raised after the Napoleonic wars, have depended on seed from other European countries.

http://oadb.tsl.ac.uk/?p=371

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

Based on a literature survey, we provide an overview of the present knowledge on ash dieback, identify practical recommendations and point out research needs. The observation of relatively resistant individual ash trees (although at very low frequency) calls for a rapid germplasm collection effort to establish a breeding program for resistance or tolerance to the disease. Ash trees that appear to be tolerant to the pathogen should not be felled.

Given that the pathogen does not form propagules on wood, and given the importance of deadwood for biodiversity conservation, dead and dying ash trees should be left in the forest.

Conservation biologists, landscape managers, restoration ecologists, social scientists and tree geneticists need to engage with forest pathologists and the various stakeholders throughout the distributional range of F. excelsior so as to tackle this pressing conservation challenge.

http://www.sciencedirect.com/science/article/pii/S0006320712003813