Q.Ivory Lilac Tree Planted 3 Years Ago Doesn\’t Have Hardly Any Leaves But Has Light Green Stuff On The Trunk That I Can Scrap Off
. if this killing my tree
Certified GKH Gardening Expert
It sounds like you are describing lichens! These are harmless to your tree, but do have a relationship with more harmful fungi, sometimes. Usually, though, the fungi are harmless too. Likely, it is there because of another fungi.
With that being said, it is possible that your tree has another infection. A fungicide may be necessary.
Here are some articles that will help: