[lacewing]

The leaves on my acid cherry tree are turning yellow with black markings and  dropping off.  I also just noticed it has a bad attack of blackfly, would this be the cause or has it got a more serious problem?

[azubah]

No idea, but I'm blaming everything on the weather this year.

[lacewing]

Yes indeed, a wash out everywhere. I suppose we ought to be glad of what little we do get.

[New shoot]

Yellow leaves can be a sign of too much water or waterlogged soil.  Could this be the case?

If the leaves are going black as well, this could be a fungal disease which has set in on leaves which are already struggling or sooty mould living on the honeydew dropped by the blackfly.  Blackfly will weaken a tree but should not kill it.

Any chance of some pics of the leaves as that may help pin down exactly what is wrong  

[lacewing]

We are on very free draining soil, which makes me doubt that waterlogging is the problem, even with amount of rain that has fallen in recent months. The blackfly is pretty dire and I have now resorted to spraying. And yes the leaves are also turning black. I will take some picks tomorrow and try to upload them, which I'm not very good at but will give it a try.