cauterizing canker on cherry tree
I live in Redmond, WA. I bought a multi-graft cherry tree a year and 3 months ago. The graft has branches for: bing, rainier, van, sam, and stella. In Redmond, Washington, it rains every day all year, except during July through August. Last summer, the tree gave 2 cherries. This summer it gave hundreds.
However, in early Spring, I noticed that the center trunk of the bing part of the graft started to ooze sap. Not knowing anything about trees, I figured this was normal, but as the months went by, the area that oozed started to open up into a wound. Several weeks ago, after doing allot of searching on the web, I self diagnosed the issue as canker. The treatments I came across suggested: (i) spray with anti-fungal copper sprays, (ii) use a sharp knife to cut out the rotten part of the canker and then seal it with a special paint, (iii) cut the entire branch of the tree well below the canker, and (iv) cauterize the canker using a small accurate blow torch.
My tree is very small, too small to use either cutting option. So I decided to start with the sprays. The sprays didn't help. The dry July weather didn't help. Waiting didn't help. The canker was getting larger with each week. It got so large that I could see the inner wood of the tree. Unless I used a scalpel, I wouldn't be able to cut precisely enough to not just cut through the tree.
So I decided to get a small blow torch and last week I cauterized the canker. I burned not just the inner part of the canker, I also burned a couple centimeters around the edge of the canker. It has been a week now and the cauterized canker has not oozed the slightest bit. The branches, leafs, etc, above the cauterized canker seem to be doing fine.
I am hoping that this stopped the canker and saved the tree. If not, I will be forced to cut the top half of my tree off, which will mean all of the bing branches are gone.
Has anybody else used cauterization to treat cankes?