Cherry tree problem

A friend has a cherry tree, morello I believe. It's 5 or 6 years old, and around 4ft tall. It's not been pruned.

Every year, the cherries appear and then every year, so she thought, the birds were getting them - so last year, I put up a big cage around it. But the cherries still disappeared, when they were roughly 1/3" big.

On closer inspection, I found them on the ground, dried and shrivelled, and then more on the tree going the same way. Not knowing what it was, I took off all the bad ones and cleared away the fallen.

On the tree itself, there were a number of curled leaves, which had blackfly in - I'm assuming this is the cherry blackfly. I removed these as well in case they were causing the problem with the fruit.

Is this likely, or I do we have two different issues going on? What can we do to get this tree fruiting properly?

 

Anyone...? Tree is now coming into blossom so we would like to stop it happening again!

 

This happened to mine last year and was due to it running out of water.

 

Cherry blackfly is really damaging. They make the leaves curl up with the blackfly inside the curled up leaves which means spraying with a contact spray like soapy water is useless. I had a cherry that every year got attacked by blackfly and I think it so weakens the tree that the fruit drops off.....that's my theory anyway. Eventually I gave up on the cherry tree sadly and planted something else.

 

in the old days they used to spray fruit trees with a solution made of sulphur, but I am not sure that it is allowed anymore for environmental reasons. Check. But I would imagine that the damage is already done now, if you say that the tree is in flower...

 

It's just getting started. I don't know if there was any problem with the blossoms last year but it did start to fruit - the cherries got to about 1/3" before they started to shrivel up and fall off. So something's happening in that time frame. I suspect it is the black fly so I want to treat for them as a starting point, I just want to make sure I use the right stuff!

 

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