Honey Locust Tree Suddenly Started Dropping Inner Leaves

Question From: J. Rezek - Show Low, Arizona, United States
Q: My Honey Locust tree has suddenly started dropping its leafs from the inner parts of the tree leaving the stems in place. The new growth still seems to be healthy. I have inspected the distressed leafs just before they fall with a magnifying glass and I cannot detect any insects, webs, etc. I am deep watering once a week and have been applying fertilizer. It has been an unusually warm spring with temperatures in the 90's.
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A: John, If it were my tree I would get an onsite inspection from a professional. To find a certified arborist in your area go to www.tcia.org. Best And Happy Yardening, Nancy