92aea58e____Friends_of_the_Urban_Forest__Possible_Causes
[Symptom] The leaves generally wilt and brown within 1-3 days and the tree does not recover. [Solution] This could include but is not limited to: painting chemicals, motor oil, cleaning solvents, etc. Painting chemicals seem to cause the most sudden and dramatic tree death when dumped into tree basins. Be sure that any contractors you hire understand that they are not to dump any toxins in the tree basins (including the neighbor’s!) and that they are responsible for the cost of removing and replacing any trees that die if they do. If you suspect chemical dump, gather some soil with a trowel and smell it. You may detect a chemical odor. [Possible Causes] 
Chemicals dumped into tree basin
Common Problems & Disorders | Friends of the Urban Forest
Possible Causes