What to spray on apple trees and how often
Oakland County Michigan
For home apple grower sprays where you need to protect against insects, and diseases I recommend this short resource from the University of Kentucky https://plantpathology.ca.uky.edu/files/ppfs-fr-t-18.pdf
Here is a good resource on home fruit tree care.
They also have a good resource for pest control.https://www.extension.purdue.edu/extmedia/ID/ID-146-W.pdf