what diseases to watch out for with scion wood swaps?
Thomis in the thread on eliminating poor apple varieties said that he doesn't want to swap scion wood any more because he received badly diseased wood. I thought I'd start a new thread to explore that tangent. I assume some diseases might simply kill the scion, but what diseases (and with which species) are potential long-term problems and how contagious are they? What diseases are you all particularly careful about?