Mulberry Tree With Dead Leaves and Grass at Base
We are in Florida. We bought a Mulberry tree a year ago in September. We kept it in the pot too long, and it started to drop leaves. We finally planted it. Then, soon after, a storm knocked it sideways. We put supports on it. That was winter. No leaves at all. We asked a tree service if it would live. They said it was dead. We didn't give up on it, so in the spring, it came back. It had lots of healthy leaves. Then, a few months ago (June), some leaves started with dark areas and then turned yellow and dropped. Now it has about 8 branches with 8 sickly leaves each. One branch with new, green healthy leaves. We noticed last week that the grass at the base was dead and yellow in a perfect circle. Do you know what caused this? We do have a neighbor who "takes care" of our plants sometimes without permission. He has removed lots of elderberry and firebush thinking they were weeds. I'm wondering if he tried to fertilize it?
Certified GKH Gardening Expert
It sounds like the leaves have a fungus, but that would not have caused the yellow patch at the base.
I would say that it is possible that the tree's roots were burned by a fertilizer that was too concentrated, which would have also killed the grass. This may have been applied because someone thought fertilizer would help with the fungus on the leaves (it won't).
Treat the leaves with a fungicide. This will help them to recover and regrow. Increase watering to the tree and apply some bone meal. Bone meal will not burn the roots but will help the tree start to regrow any roots that may have been burned by possible fertilizer burn and the extra water will help leach away any excess fertilizer that may be in the soil.