QuestionI have researched what causes the transparent (looks like white) spots and holes on the rose leaves and have found multiple answers such as small slugs and mildew. Can you clarify which answer is correct?
I live in Chicago. In my case, the leaves have many small transparent areas because the underside of the leaf is not there. There are many small irregular holes on the leaves as well. Because a few of the holes have a small transparent portion next to them, one may assume that the transparent areas turn into holes. Is this caused by a fungus, slugs or something else and what is the remedy? Thank you.
AnswerRose slugs always eat from the undersides of the rose leaves. When they do, the leaf hole on the top side dies and you get the holes. The slugs make small holes all about the same size. Rose slugs do make holes but that doesn't cause the leaf to die and fall off unless there is a very large amount of holes. Downey mildew burns the leaves on the top side and that in time kills a large part of the leaf. Because the damage is large, it finally kills the leaf which then drops off. Downy mildew is a pale grey blotch with no definite outline to it.
