The rapid spread of ash die-back Hymenoscyphus fraxineus is resulting in the loss of ash trees at a landscape-scale. The impact of this loss on ash-dependant lichens has hitherto been unknown. The risk from ash dieback was assessed for 20 Section 41 species with varying dependencies on ash. Notably 8 species are considered to be at high, or very high risk of extinction from the loss of ash.
Potential mitigation approaches to reduce the impact of ash die-back on lichen are evaluated. Five case-studies are presented which discuss the application of these approaches to specific sites and issues. These are Gowbarrow/Glencoyne Park in Cumbria, Bovey Valley in Devon, Horner in Somerset, Dunsland Park in Devon and Arlington Court in Devon.