Fruit tree disease mystery

Last summer, I had four different fruit trees die and I'm not sure what killed them. I'm hoping someone here can help me because the rootstocks of all four survived and I'd love to regraft onto them but I don't want to reinfect whatever I put on there without knowing what happened in the first place. I'm also concerned that whatever will spread to the uninfected trees.

All four were very different trees and surrounded by trees that were just fine. There was an apple, a pear, an apricot and a plum. They were all planted 3 years ago and were about 5-6' tall and not bigger than 1-2" diameter trunks.

The apricot's death was a little different and I think it was a borer infestation because the ends of the branches started getting very limp and dying back to the trunk and I found a few tiny holes down on the trunk. Does that sound correct?

The others died from the leaves back as well but did not get limp and there were no holes, at least none that I saw. What happened was that the leaves started getting black spots on them and then the leaves turned completely black and crispy (but not shriveled) and then the stems turned black and the black worked its way down the trunk. I've looked up all the common diseases but I haven't found one that matches what I saw. Any guesses? It was really hot last summer and they seemed to get worse the more I watered them if that gives any clues.

In the seven years that we've lived here and been planting fruit trees, the only problem I've had so far is pear sawfly but I guess it takes a little while for the icky things to find their way when you are starting from scratch. It was pretty shocking to watch my trees turn from green to black (something like a scene from Moana).

TIA!

Sorry I don't have any advice, but I am curious as to what, if any practices you used once you determined the extent of the damage being done? Did you cut the trees down to a stump in order for the roots to survive? Does that even work? I'm very new to trees and trying to learn all the differences between types and techniques used to keep them alive and producing well!

I must admit I'm still in awe of grafting, coppicing, pruning, bare root seedlings, etc...amazing stuff!

A slight positive though, that only one example of each type has been hit by major problems and others survived!? Surely your diversity of planting over the last 7  years is beneficial.

The trees that had black spots o the leaves may have been a bacteria or fungal infection.  The method to remedy this is a fungal spray and cut off the infected limbs and dispose of them properly.

You may want to contact  local Master Gardner https://extension.wsu.edu/pierce/submit-a-gardening-question/
Even though I am in the same county am at sea level and my conditions are so different.
Possible some were contaminated during grafting or handling the scion.

Cole Tyler wrote:Sorry I don't have any advice, but I am curious as to what, if any practices you used once you determined the extent of the damage being done? Did you cut the trees down to a stump in order for the roots to survive? Does that even work?

I did absolutely nothing except observe and Google to try to figure out what was happening. I think you can do more harm than good if you don't know what you are trying to treat and I didn't know. Also I'm of a mind that if I have to work too hard to keep something alive, then it's probably not a plant I need on my property. Though I like to understand what's going on so if it's a simple remedy or I made some kind of avoidable mistake.

The rootstocks of all of them must be resistant to whatever it is so when the tops started dying, the roots immediately started putting energy into sprouting and those sprouts are a few feet tall at the moment and looking healthy.

Cole Tyler wrote:
A slight positive though, that only one example of each type has been hit by major problems and others survived!? Surely your diversity of planting over the last 7  years is beneficial.

You know, that is a good point! Thanks for the bright side! 😁

Anne Miller wrote:The trees that had black spots o the leaves may have been a bacteria or fungal infection.  The method to remedy this is a fungal spray and cut off the infected limbs and dispose of them properly.

Since I don't know what it is, if it's bacterial and I were to spray with a fungal spray, would that actually do any good?

Hans Quistorff wrote:You may want to contact  local Master Gardner https://extension.wsu.edu/pierce/submit-a-gardening-question/
Even though I am in the same county am at sea level and my conditions are so different.
Possible some were contaminated during grafting or handling the scion.

Good idea! I hadn't realized they had a question submission page or I would have asked last summer. Thank you!

You are right that our county varies so much, especially with the Puget Sound, the mountains and all the hills and valleys in between.I love all the diversity of ecosystems around here! 😁

Jenny Wright wrote:Since I don't know what it is, if it's bacterial and I were to spray with a fungal spray, would that actually do any good?

Since maybe the diseased parts might have already died there is not much that can be done now.

When the trees start budding out and you see the black spots again, I would suggest taking a sample to your County Extension Office to get a diagnosis.  That way you will know exactly what it now is whether bacterial or fungal and the Extension office will probably recommend a treatment.