Thank you for contacting the UVM Master Gardner Helpline with your question with pictures.

I reached out to the Director of the Plant Diagnostic Clinic for her recommendation. Ann’s response was:

” I doubt the dead branches have anything to do with lack of water, ie rain. I would suspect a problem at the base of those branches, like a canker or injury. The only thing to do at this point is to prune out the dead branches back to the main branch or trunk when the tree is dry and burn. They may want to thin some of the branches and remove any dead or weakened branches in the entire tree.”

This article written by Texas A&M AgriLife Extension entitled “Tree Care Kit – After the storm wound care” will provide you with information about cutting the dead limbs out of your tree – https://agrilife.org/treecarekit/after-the-storm/tree-wounds/

Specifically, this quote:

“Pruning cuts should be made to maximize the tree’s ability to close its wound and defend itself from infection. When pruning, make clean, smooth cuts. Do not leave branch stubs. Leave a small collar of wood at the base of the branch. The branch collar is a slightly swollen area where the branch attaches to the trunk. Cutting the limb flush with the trunk will leave a larger area to callus over and a greater chance of decay organisms entering the wound. The optimal pruning time is in the winter (dormant season) when temperatures and infection rates are lower and when trees are not actively growing.

“Conclusion. Healthy trees usually recover from wounding quickly. Try to keep wounded trees growing vigorously by watering them during droughts and providing proper fertilization. This will increase the rate of wound closure, enhance callus growth and improve the resistance to decay mechanisms.”

End Quote

Please note that Ann recommended that you burn the dead branches you remove from your tree.

This article “Pruning Trees and Shrubs” recommends tools for pruning and lots of other valuable information: https://extension.umn.edu/planting-and-growing-guides/pruning-trees-and-shrubs

For your future reference in this article entitled “Fruit Tree Pruning: A Rules Based Approach” written by Pennsylvania State Extension you will find information about how to decide what branches to prune out of your tree. https://extension.psu.edu/fruit-tree-pruning-a-rules-based-approach

Also, this article by North Dakota State University “Dakota Gardener: When Pruning Apple Trees Keep it Simple” https://www.ag.ndsu.edu/news/columns/dakota-gardener/dakota-gardener-when-pruning-apple-trees-keep-it-simple

I also found this article about late pruning of apple trees. I know it doesn’t apply to your question, but it is interesting research: “Fruit Tree Pruning – Summer Pruning Cautions”: https://extension.psu.edu/fruit-tree-pruning-summer-pruning-cautions

You will also find lots of miscellaneous home gardening information on the Master Gardner “Gardening Resources” website: https://www.uvm.edu/extension/mastergardener/gardening-resources

I hope this information is helpful. If you need more information, please feel free to reach out. Good luck with your apple tree.