I arrived early at the Woodland Trust‘s Londonthorpe Wood on Saturday morning – it was too breezy for photographs of most flora but these conveniently static lichens, attached to equally anchored trees, caught my eye.
I am very out of practise on lichen ID so the suggestions below are tentative only!
Ash trees are very important to lichens – the light dappled shade produced by the canopy is ideal for tree-bark lichens and the bark has a relatively high pH, a requirement for many lichens. This page from the Lichen Society has more information. If the spread of Chalara (ash dieback) continues to affect our ash trees, this might significantly impact upon our lichen populations.