I have three magnolia trees. The back side of all three trees have lost their leaves. The leaves turned brown and have fallen off. This happened during the winter and it looks like something just came through and blew all the leaves off. What disease do you think they might have? Will they repair or should I have them cut down? They are 21 years old.
It's a good idea to wait for warmer spring temperatures to determine the extent of the damage to the trees.
The damage could be superficial and the trees can make a recovery over some time.
Once the temperatures have warmed you can clear away any dead branches and leaves.
Examine the tree for more extensive damage such as frost cracks in the branches and trunks.
You can apply a light fertilizer and mulch to help the tree in recovery.
Small frost cracks or damage can recover on their own but larger damaged areas can need some help.
A fixed copper can be applied to larger wounds on the tree.
Then you are in a wait and see period. You can then determine if the trees are going to recover enough for your landscape.
If you are going to replace the trees with Magnolia again, look for cold hardy varieties that are resistant to winter weather issues.
Planting in an area that is sheltered from winter winds will also help the trees.
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