Fireblight emergency surgery?

Should any spraying be done now? When should I apply my dormant spraying?

I’ve got some similar looking cankers, some on main scaffolds. I don’t know what will happen as the tree tries to close it off, but I’m probably pruning it out unless someone with some more knowledge persuades me not to.

Following up on my Priscilla FB trunk canker emergency surgery. As I mentioned I ignored perfectly good advice from the gurus on here and decided to just cut out as much of the infected bark as possible rather than cut off the trunk below the lowest branch. Here is what it looks like now 7 months after cutting out the canker. Scroll up to my earlier post if you want to see the before photo. You can see that I had to cut way down toward the ground to get out all the wood that looked OK on the surface but was discolored underneath. Yeah it looks kind of bad but the black stuff on the underlying wood is just mildew. The bark seems to be healing over and hopefully most of it will close itself off this summer. We’ll see what happens. Should be interesting. Obviously if I had a lot of trees I’d probably have just cut it off, but I can afford to baby these things and try different approaches to learn something (maybe the hard way if it dies haha).


Follow up on this FB canker on my arkansas black that I let go to see what happens. It was fine all this spring but was healing very slowly. Definitely no sign of FB at the canker site all summer. The blossoms and shoots got some FB like all my other trees, but not this wound. Then within the last few weeks the bark started looking kind of water soaked and dark. Then It started seeping FB juice. So I cut out a bunch of the wood. I had to go very deep to get to clean wood because the tree grew new clean wood over top of infected wood. I hope I got all of it. Moral of the story which most of you already knew but I had to prove to myself: never hesitate to cut out a canker when you have the chance.


On the other hand, the big surgery I did on the Priscilla to cut out the FB has been a success. No sign of FB and that huge long wound has closed off except for the very top.


@barry: earlier in the Priscilla thread you wrote: “You can see that I had to cut way down toward the ground to get out all the wood that looked OK on the surface but was discolored underneath.”

What color was the “discolored underneath?” Was the cambium discolored?

It was brownish, maybe a bit rusty colored. Update on that tree…i grafted to some branches and all grafts got fb, and it had lots of shoot blight on existing wood. I started cutting it up and found that even though the wood had totally healed over with new bark on the trunk wound, there was fb still lurking underneath and moving down the trunk and maybe moving systemically throughout the tree. Eventually i ended up with a stump that was oozing fb, and no new shoots ever sproutd from the stump. I eventually ripped it out. Not a happy ending, but it took a couple of years to play out.

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Sorry to hear Priscilla bit the dust. I am puzzled why so many people remark about fireblight discoloring the cambium when what I’m calling blight here does not discolor the cambium: it’s beautiful bright green. Trying to figure this out. Discoloration would make it easy to see how far to cut.

I could be mistaken but i seem to remember on larger or older wood (2yr+) that the cambium may still look ok (green) with discoloration mainly in the wood below. Only on the externally visible cankers would the cambium look bad. But i dont have photos so im not completely certain on that. Do you have photos to post?