Orange Pippin Forum Board

Can anyone help me identify this apple malady?

I immediately thought fireblight, but temperatures haven't really been pushing 18C too much where I live, and having peeled some bark back there is no discolouration.

The symptoms are dark discolouration of the leaves and wilting and just generally looking sorry for itself. I quite like this tree so I'd rather let it battle on and see if it can overcome this, but if it is something really nasty like fireblight I'll rip it out to save the rest of my trees.

I don't suppose it could be something as simple as (lack of) water stress....

I doubt it, I live in the UK so it rains 25 hours a day. Also out of 14 apple trees, it's the only one with those specific symptoms.

Perhaps a honeyfungus or something similar is attacking its roots.

Fireblight is unlikely in the UK. A more likely cause is that the roots might have been in standing water all winter, since this has been a very long wet but mild winter.

This looks to be downy mildew. It attacks the young leaves and they respond by trying to limit the spread of the disease by dying back (the black necrosis you see). The dirty grey surface to the leaves are the fungal hyphae growing across the surface. Damp, warm conditions cause this early outbreak. Try to get a systemic fungicide on it to prevent the new leaves from being infected.