Apple disease

Asked August 31, 2017, 5:36 PM EDT

What disease is on my apple tree? And how do I treat it?

Barry County Michigan

1 Response

On the fruit the hole is caused by codling moth, or perhaps oriental fruit moth. The sawdust-looking frass is from the larvae. You may be able to still find a light, slightly pink colored larvae. Codling moth and oriental fruit moth are controlled by spraying with insecticide starting when the fruit becomes about 1 inch in diameter.

Here is a link to an article with details about controlling these insects.

http://williamshane.weebly.com/uploads/2/7/0/7/27077603/apple_spray_for_non-commercial_growers.pdf

The spots on the leaves are caused by a rust fungus, maybe cedar apple rust or possibly juniper rust. See the following article for further details, including control strategies.

http://msue.anr.msu.edu/news/cedar_apple_rust_a_tale_of_a_fungal_disease_with_two_hosts