I have some trees on a commercial lot that were planted 2 winters ago the following summer was a drought but had irrigation system on them anyway theres some locust trees (not positive) 15 footers where some of the top and 1/2 of some side branches has died back the problem is that I cant determine a main leader how would these trees be pruned properly? there are also some sycamores where 1/2 tip of all branches have dies and there is very much spout growth any tips would be much appreciated<br>Mike