Hi, This year like no other my flowering crab trees (6 Red Splendor variety) are dropping leaves (50% at least). And I can't help but notice other crab trees in the community in some cases are nearly defoliated. Will this lead to the trees dying? Will they revive next spring? My trees are all at least 12 years old. I do not wish to have to treat them with chemicals year after year. They are too big to thoroughly cover-spray anyway. Should I expect this will be the new normal for them? Cannot recall this much of a problem before. Thank you