Au Cherry Plum on Probation

[Auburn]

I wasn’t expecting this on my Au Cherry. I was lucky that it was located on an easily removed limb.

[ammoun]

Oh wow! What is that?

[Auburn]

I’m not sure but I assume it is black knot. It is very dark but the flash brightened it. I edited in a darker picture but it’s not well focused.

[DAVELn17]

I seem to have the same issue. See the picture. Should I trim off the entire branch. It is on a flavor supreme.

[Auburn]

I tend to cut off at least a few inches below damage and more if it doesn’t totally upset the tree structure.

[DAVELn17]

Thanks…

[kakasamo]

What is the causative agent of this black knot?

[Auburn]

I can’t answer the why but some trees are more susceptible than others at my location. As of now my Chickasaw plums have not had any black knot.

[mamuang]

I have them on both Euro and Japanese plums. I am starting to get tired of stone fruit being disease prone, to be honest.

[Everett]

The wild cherry trees (black cherry and chokecherry both) around me are huge carriers of black knot, almost all of them have it. They give it to all stone fruit if you don’t actively cut it off of the field edges. We have had a huge problem with plums in the past. Do you have any wild cherry growing nearby by chance?

[scottfsmith]

I had bad black knot on one of the AU plums as well. Not Cherry or Producer, one of the other popular ones. This year has been your standard knot year for me, I have removed maybe a dozen small limbs and 4-5 big ones I had to do surgery on. On the bigger limbs when the knot doesn’t go all around I just use a knife and remove the knot and keep doing it til it is done. Cut away from yourself if you do that, don’t forget the old wood whittler’s lesson.

[Auburn]

Do you have any wild cherry growing nearby by chance?

Wild cherry trees grow everywhere around my place.

[Auburn]

All my AU plums have had a little black knot except AU Rosa which is still small. Fortunately they have only had a small manageable amount. If they are a constant issues I will totally remove them. As of now the Chickasaws haven’t had any BK (Guthrie and Odom). Spring Satin has also been disease free.

[scottfsmith]

Spring Satin was more or less knot-proof for me. It was right by a bunch of knot magnets and never got any. If that plum just ripened well for me it could have been at the top of my list.