I have this problem with plum trees in our orchard , could you identify ?
Outside United States plum diseases
Thank you for your question. Since we do not know your location, we are unable to narrow down potential diseases (and/or insects) in your region. Perhaps you can use the photos in the following article to compare with your tree to narrow the range: https://plantvillage.psu.edu/topics/plum-and-prune/infos Good luck!