Cut one of the branches and see if the cross section looks healthy.

Looks good from my inexperienced eye. The grey coloring is from a not so clean blade. Forgot to mention in case it makes any difference - it is about 3-4 years old and it was fruiting this year first time but only a handful of cherries. I sprayed all fruit trees twice with a very light dose of neem oil (25ml / 5l water).

Did you ever figure out the problem? My sour cherry had the same problem this year. I'm afraid it's the early stages of shot hole fungus, but I'm not certain.

Could you have given it too much water? If the roots drown in water-logged soil, they tree can begin to head downhill very fast. Cherries often need consistent watering, but not too much at any one time. It looks like your tree has gone into shock, there is probably an issue with the roots. I would stop watering for the next 3 months (after the second month give it just enough water to keep the soil mildly moist) and see if the tree sends out new leaves.

Sometimes these things can happen and a cherry tree can die for seemingly no reason. Another possible problem, it could be planted too close to that bush, the roots of some bushes can interfere with the roots of fruit trees.

Cherry leafspot disease can kill sour cherries. Animals could be chewing on the roots underground. In some cases it is a combination of 2 different factors that result in the tree's death.

Thanks for the feedback - you've woken me up to this problem - too many other jobs, so I haven't done anything about it for a while. I had an agricultural engineer who has a local shop come around but he wasn't clear on what the problem was/ couldn't identify it. He pointed mainly back to the tree itself - bad stock. His only suggestion is as is written on the pages I looked up about fungus (eg as wm3y said - for shot hole disease) - copper and sulphur spray and to spray a bit on the ground around the tree Unfortunately I'm too busy and haven't done that yet - on the to do list.

I cut down two apricots and a fig on the other side of the house, so not sure how it will go with this cherry -will see in the spring.

Regarding other factors -difficult to say. The other tree could be a problem - it's in the way of grapes also, but my wife's mother gave it to us, so removing it has some other problems tied to it ;) - I was thinking of planting cuttings somewhere else and may do so next spring. Animals - not sure what it could be - I think it could only be some insect if it's not a fungus/disease as we don't have any animal problems, and I haven't seen any signs of chewing etc. when I pulled out the apricots. The story with the fig may have been partly to do with my pruning it hard towards the end of summer and too much water- it developed cracks between the trunk and branches and dried up. Maybe I overwatered it - with my desire to plant everywhere, I had vegetables growing underneath it and was watering them -maybe it was the water, but the strange thing was that it was easy to pull the tree out. I didn't find much of the root system at all but I couldn't see that they'd been chewed either - a mystery to me.

On the other hand, it may have to do with the soil/watering and corresponding good conditions for fungus development. The soil is quiet compacted, so outside the area the tree was planted where there is manure/compost etc, we have a different scenario and with my desire to do deep watering, maybe I did overwater for the type of soil that is there - but how do you deep water without watering ;) ?.

I'm gardening because I'd like to have natural food without chemicals but to be honest, it's quite difficult if you're not always on top of things and studying up on things more and more and I don't have the required time for this to do it properly, so I'm happy with the plants that do well and for the others I try my best.

For deep watering, I usually leave the hose on very low, just a trickle, for several hours, and come back to it later. Gives plenty of time for the water to seep down in there and drain outwards. It's like a drip irrigation system.

My problem is that I don't know what my problem is ;) When we moved here (hot summers), I used to hand water everything and it took approx. 3 hours every couple of days. It was irritating standing there in the evening after being tired out over the day and "disturbing" guests (we have a few apartments) as I walked around, not to mention the amount of water that I used. Next, I put one big drip irrigation system in place with a few valves -it wasn't perfect and it wasn't easy to give the right amount of water to different types of plants. Now, I have have 10 circuits and can water what I want and as I switched everything to 2l inbuilt valves, I can water quite precisely if needed. The last step is missing to put on the electric valves and automate it , so watering is not my problem - I just can't get it right in some way for some plants - or it's like the engineer said - maybe the tree really wasn't OK from day one.

The cherry and the apricot and fig trees that I removed are not the only plants here - I have vegetables, berries, citrus, kiwi and a few others but I don't have such problems with them for some reason. Maybe I don't have a green finger yet ;)