How virulent is bacterial canker in cherries

I have found what I am pretty sure is bacterial canker in a pair of Evans cherries. I was suspicious of the injuries last year, but it seems rather undeniable now.
To remove completely will take 40-60% of each tree, as there are patches on primary scaffolds on one and trunk on the other.
I know it has to go, but it would be nice to wait and see if weather let’s us pull a crop on it this year (always a gamble for us) before cutting it out.

So how virulent is bacterial canker? How quickly should one act to eliminate it. It should also be considered that there are many wild black and pin cherry in the surrounding woods, so a certain base load presence must be accepted.

You can eliminate it from your trees and prevent re-infection with periodic applications of DuPont Kocide 3000. The dosage instructions on the label are very good. However, a tree with 60% infection rate might not survive.

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Yes copper is the only treatment or preventative, but I must say it sucks. Every cherry I have had so far, has eventuality succumb to bacterial canker. The east is way different. I’m hoping the Romance series of cherries fairs better. I do use Kocide for example I use before pruning, and spray again after pruning, as the incidence of canker is so high. I now only prune in the summer too during our driest period. If it was dry around here the copper would work well. I can keep them alive about 6 years. I’m also hoping the new releases out of NY are truly canker resistant as they advertize. One of those Cornell trees will be my next cherry tree. I’m now down to two sweet cherry trees, the youngest is a White Gold, and it is 2nd leaf, and it looks like it has canker. Just a small spot near the graft. But they always start small and finish big. The other tree is infected all over. it’s 35 miles away from the White Gold, else I would have removed it long ago. Keeping canker off sweet cherries here is like playing whack-a-mole. No matter what you do it’s eventually game over.

I’m not giving up. Sometimes you just get unlucky, I know many grow sweets around here.

You’re applying every six weeks?

Mostly in the fall and spring, not all the time. Only when conditions are bad. Sweet cherries are sensitive to copper, you can’t just keep using it. We have a problem here with canker. This article is informative as to what I’m up against.

Note this quote
In field
experiments we performed at the Northwest Michigan
Horticultural Research Station (NWMHRS), either copper hydroxide or
copper sulfate applied at white bud kept PSS populations steady or reduced them
slightly on flowers over the next four days after treatment as flowers opened
on the tree. Within two days, the PSS populations then increased back to levels
on unsprayed trees
.

I think it really has to be removed rob. The copper hasn’t helped me although I know it’s supposed to. To me it’s kinda like treating a shotgun wound with topically applied merthiolate…it helps but isn’t going to cure it. I’m in the same boat…exactly the same boat. I have canker on my Montmorency and I’ve decided I am going to wait until after harvest. I’ve cut out portions before and it seems to come back elsewhere. I would guess that I probably spray more than anybody here including the commercial guys and it is just persistent. It seems to be systemic, but I’m not sure it works that way.
Speaking of merthiolate, one night I couldn’t sleep and was laying in bed thinking about Povidone Iodine and wondering if it had ever been tried on tree injuries and canker. I got up out of bed and went downstairs and got online. Sure enough it had been studied and had been found effective. I might just try it after harvest.

[quote=“Appleseed70, post:6, topic:946, full:true”]
I think it really has to be removed rob. The copper hasn’t helped me although I know it’s supposed to. To me it’s kinda like treating a shotgun wound with topically applied merthiolate…it helps but isn’t going to cure it. I’m in the same boat…exactly the same boat. I have canker on my Montmorency and I’ve decided I am going to wait until after harvest. I’ve cut out portions before and it seems to come back elsewhere. I would guess that I probably spray more than anybody here including the commercial guys and it is just persistent. It seems to be systemic, but I’m not sure it works that way.Speaking of merthiolate, one night I couldn’t sleep and was laying in bed thinking about Povidone Iodine and wondering if it had ever been tried on tree injuries and canker. I got up out of bed and went downstairs and got online. Sure enough it had been studied and had been found effective. I might just try it after harvest.
Meant to reply to Rob.