Question
Our tree has been planted for 5 years. This year I am seeing black spots on lower branches of trees and new leaves coming out on the top are dying.

Answer
Maples will act funny like what you describe.  The black spots on leaves could be a fungal disease called tar spot.  A fungicide would help this situation.  Daconil is a good protectant fungicide that can be found at most good garden centers.  Mix according to instructions for ornamentals and treat the entire tree if possible.  Then wait 7-10 days and treat again.  The spots will not go away, but the new growth should stay healthy.  If you see spots developing on the new growth, treat again.  I hope this helps solve the problem.  Good Luck.