Thornless Golden Honey Locust Tree Has Thinned Out And Leaves Turned Yellow Brown And Crepe Myrtle Has White Dust

Question From: Hemet, California, United States
Q: I live in California in the desert and I planted two thornless golden honey locust trees in 2006. The last three years they have been beautiful in that they have grown tall and have plenty of branches and leaves. This year one of my trees has started to get thinned out with leaves and they are turn yellow to brown like would happen in the fall going into winter. Do I have a diseased tree and will it affect the other tree which is close in proximity to the sick tree? It is also near a crape myrtle tree which has this white dust on it this year too and I think that tree is also diseased for crape myrtles.

A: Your one honey locust is probably dying. If it has a disease it may well spread to the others. I can't diagnose the cause, but lack of water comes to mind. Your crepe myrtle has powdery mildew, a fungus and is also in stress. If they were my trees and I wanted to save them I would get an onsite inspection from a certified arborist. Go to and enter your zip code to find one in your area. Best Nancy