Answer: Unfortunately, based on your description I am not able to diagnose the problem(s) affecting your tree. For instance, the leaf spots could be due to a variety of fungal or leaf spot problems, the leaf curl could be related to a verticillium infection, and the stickiness and dark spots might be related to a pest infestation such as aphids which would secrete honeydue on which sooty mold then forms. For this reason I would strongly suggest you consult with your local Cornell extension and/or a professionally trained and certified arborist with experience in ornamental trees to try to obtain a specific diagnosis. Based on knowing that, you can decide what to do for the tree. If a chemical control is needed, your county extension should have the most up to date information on what to use and how/when is best to apply it for maximum results. I'm sorry you are having trouble with your tree and I wish I could be more specific for you but this requires more of an on-site diagnosis.
Q&A Library Searching Tips