I have a 15 year old Granny Smith tree that I’ve never had any issues with. This year, I am getting die back on some fruiting wood, mostly the tips. When looking at the wood and leaves under a magnifying glass, I am seeing very small amber droplets. The leaves have some brown areas by the stems. As the attached photos show, this is happening on branches that have fruited.
I have never sprayed this tree with an anti fungal, either during the growing season or when dormant. The majority of the tree looks great.
Thanks everyone for the info. Not what I wanted to hear, but good to know what I’m dealing with. I’ve cut back the areas that have the die back and will spray with copper next year before bud break. Anything else I should be doing?