What could this be?
I have a mini Crab Apple tree, could you tell me if this is Cedar Apple Rust Disease or is it something else? On the underside of the leaf you can feel that it has a bump there. The bump seems to be under all of the spots. I haven't seen any spores that protrude out of the bumps. I have attached 3 pictures the first two are of the same leaf. Pic 1 is the front of the leaf. Pic 2 is the back. Picture 3 is of a cluster of leaves. Thank you
Yes, this does appear to be cedar apple rust. The fungal tubes may have yet to form. Check out the following links for more detail and control methods:
I hope this is helpful.