I have chokecherries in Perham, MN. They produced very well until a black...
I have chokecherries in Perham, MN. They produced very well until a black fungus started growing on the stems. How can I cure them? Pat Riestenberg
Otter Tail County Minnesota chokecherry trees
Without seeing a photo I am guessing that your chokecherries have black knot. Most of our native cherries and their relatives are very susceptible to this disease. Here is information that should help you try to control it:
I hope this is helpful. Please contact AaE again if you have further questions.