What is wrong with my magnolia tree?
Answers:
No Magnolia tree is too old. I have two beautiful Magnolias in my front yard which are 60 years old. The problem could be that a disease from a surrounding oak has infected your tree. One of our two trees developed a disease a year ago. We completely pruned back the tree discarding all of the diseased limbs. We then used pesticide and watered every day. The trees are once again beautiful.
Other answers:
Too Old
Too Old
I've experienced some trees, newly planted or within a couple years, that the main body of the one you planted dies, while it still brings forth life near the bottom as your magnolia. I would just leave it alone and let it do it's own thing. If this happens to be a big magnolia, and there are no leaves one it, time to break out the chainsaw.
Your tree may have died. Sometimes they just up and die. Maybe the drought last year? It's hard to say without more information.