I have a 5 year southern magnolia that is losing it leaves and the branches are dying. I notice green spots that look like mildew creeping up the tree. The bottom of the magnolia's trunk is crumbling off. It has some new growth but not much. It did flower but it was later than normal. The frost hit it hard in April, but it seemed to have rebound. I have been watering it atleast once a week. Do you think it is stressed or could it have a fungi or mold problem? I, however, don't think it is an insect problem. Thanks for any help.

When a late spring frost hits, the first and most immediate evidence of damage is usually seen as the new, tender leaves wilt, dry up and then fall off a tree. Unfortunately, all too often, there is also unseen damage. The internal tissues of a tree may be damaged by severe cold in the spring. When this tissue is damaged, the tree will begin to use its reserves to aid in the recovery process. If the tree is under any kind of physiological stress though, those reserves may not be enough to pull the tree through. So it's not unusual to see a tree start to decline months or even years after a critical event like frost damage.