I have 2 plum trees that blossomed early when there were no pollinators around. I ended up with about 20 plums. I have little coverings to put on them, but when I went to put them on I found that something had done something to them and they had congealed sap on the outside. Plum Curlio or Stink bugs, something like that. I just removed them and put them in the compost tumbler. (Figure the 110F temp should kill any pupating larvae of whatever it was.)
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