Ash trees don’t tend to need iron
Question: Should I give my ash trees the same iron treatment as fruit trees?
Ash trees seldom need iron, so unless you are seeing some yellow leaves with green veins in the spring and summer months, I would save your money. They will do better with organic wood mulches on the surface.
Most ash trees seem to do all right with rock mulch but prefer the soils that have more organic material. Arizona ash seems to be an exception. Fertilize them once in late January or early February with a tree and shrub fertilizer, and that’s all they should need.
Bob Morris is a horticulture expert living in Las Vegas and professor emeritus for the University of Nevada. Visit his blog at xtremehorticulture.blogspot.com.