Ash Die-back disease

These photos show what may be signs of Ash Die-back in Todmorden. I understand that young saplings are more susceptible to the disease and they start showing signs of this from the top downwards.

Photos are of a dead sapling that died in a matter of weeks and the discoloured sapwood when the stem is cut. Nearby saplings showed purple coloured stems progressing downwards and long lesions. Leaves with brown dead bits. Only time will tell if it is the Ash disease but these symptoms are significant.

Best to look closely at the top length of young stems as the changes can be quite subtle.

This year I have seen a lot of mature Ash trees with most of their leaves eaten to the central vein. I think a saw-fly caterpillar may be the culprit but it is the first time I have ever seen Ash leaves eaten by anything. I wonder if the trees' natural defences are being weakened by the Ash disease before we can see any physical sign of it. Although Ash generally have had a very 'light' crown of leaves this year. Anyone else noticed similar?