Hymenoscyphus fraxineus

The staining is the fungus causing Ash tree Die Back, there is no cure it is thought that 80% of UK ash trees will die the only suggestion to slow the progress of the disease is clearing up the fallen leaves in the Autumn to stop the fungus overwintering. The National Trust are felling lots of them on the Calke estate but it's only Health and Safety, the ones they felled last winter are regrowing some may be resistant no one is really sure