Question
In March I planted an October Glory Maple in a full afternoon sun location.  The tree seemed to take longer for the leaves to bloom, but eventually caught up with others in the neighborhood, although I still have a lot of newly sprouted leaves.  Over the last couple days I have noticed some dark brown areas of the tree and upon closer inspection today I realized that the leaf edges of the smaller immature leaves were brown and brittle.  This happened very suddenly.  A few days ago my lawn service fertilized my yard and used a topical weed killer on a few clover patches.  Is it possible that since the Maple is newly planted that the weed killer is affecting the tree?  Last week we also had a heat spell which lasted about 5 days in which the temps were nontraditionally about 98 - 100 degrees.  I watered once during the heat spell, but could this still have compromised my tree?  The branches and trunk still appear to be healthy and most of the large leaves are still very green and healthy looking, with the exception of a few spots where a bug has munched (which doesn't appear to be chronic).  Any suggestions what this could be and how I can keep the tree leaves from dying further?

Answer
The tree is suffering from transplant shock and the high temperatures arent helping.  The tree could become quite ugly before the season is over, but I wouldnt worry about it dying.  Just keep it watered and it should be fine next year.  The chemical probably is not harming the tree unless they sprayed it directly.  The tree may defoliate a little early, but I would not worry too much about that either.  Good Luck.