Question
We have eight af. sumacs spread over an acre, various sizes.  The new leaf sprouts at the end of all the branches (small & large)within the last week are wilty looking and sticky. Leaves are dying overnight, not turning brown.  Where small limbs grow out of the larger branch looks like sap is oozing. Leaves which have not died yet stick together.  We have gone over trees thoroughly and do not find any infestation of insects or any outward evidence of what might be causing this. On one three trunk tree, leaves on two of the trunks turned brown almost over night before we realized something was going on. The other trunk seems to be holding its own so far.
Went to a local nursery but they had no idea, just tried to sell me this and that to try.  Appreciate any suggestions you might have.  As an old lady gardener at heart, I would be devastated to lose all of these beautiful trees.  Thank you very much indeed.   Liz
Just saw I could attach an image.  If you need one I will take a pic with my cell phone and figure out how to get it into computer!

Answer
Liz:
Are these newly planted trees? It would probably be best if someone could make a "house call" and see your tree in person to make an better assessment. I am assuming that you live in the US. You can contact your local county Agricultural Extension office (should be one in every county- usually in the county seat)and arrange for someone to come out and see your tree first hand.  These folks can give you a lot of unbiased information.  If you are not able to find the telephone number in the book, let me know what state and what county you live and I can look up a number (hopefully!)and let you know.
Regards
Steve