How can we tell if our mountain ash tree was poisoned?
Our mountain ash tree is turning yellow on the south side. This is the same side our neighbors recently trimmed. We think they poisoned our tree after trimming it. They have poisoned other trees and bushes on our property. 1) Is there any way we can test the limbs for poison? 2) If poison is found, is there any way we can save our tree?
It looks like iron chlorosis, which often is spotty in the canopy, or it could be fire blight, though I can't tell yet. I see no evidence of herbicide damage ( I assume that is what you mean by poison). There is no way to tell if there is herbicide damage, so the second question is moot. You should talk to your neighbors and bring this up if you believe it to be true.