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/

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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)

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