I have some well-established, apparently healthy scuppernong and muscadine vines. On some of the vines, there is a milky white, sticky, gooey substance. The grapes seem fine and I just wash the gooey stuff off if it's not too much. I wonder if you can tell me what this substance is and how to get rid of it, if necessary.
I don't find a reference to such a problem in the material I have at the house and it is not one I have seen on the scuppernong vines I visit regularly. I suggest you contact your local co-operative extension office for an answer. Check the government listings in your local telephone book for a phone number.