Marginal yellowing on apple leaves

May 22, 2015

by Terence Bradshaw

This is just a quick note to help explain a condition you may be seeing on your orchards this year. Yesterday, while passing through the orchard quickly, I noticed marginal yellowing on many leaves, similar to the picture below. My first thought was to go back and diagnose a nutritional deficiency, but Mary Concklin at University of Connecticut reminded me that this damage is common on trees treated with streptomycin and regulaid for fire blight management (and thanks Mary for the photo). No negative impacts are expected or documented from this.