Hello Joyce,

Thank you for contacting the UVM Extension Master Gardener Helpline. 

These are very large trees that may need significant work so an option would be to consider hiring a professional arborist to take a look. If interested, you can search for certified arborists near you at: https://www.treesaregood.org/findanarborist/findanarborist

If you'd like to handle them yourself, we reached out to our Extension tree fruit specialist and they recommended that you approach the pruning strategy over time. Make a handful of big cuts each year for 2-3 years. Focus on the desired tree structure -- remove the big pieces in manageable chunks.

Here are a couple of resources for renovating old apples trees:

https://extension.umaine.edu/publications/2409e/

https://extension.unh.edu/resource/growing-fruits-care-mature-backyard-apple-trees-fact-sheet

https://www.uvm.edu/~orchard/fruit/treefruit/tf_horticulture/UMASSpruningfruittrees.pdf

Good luck!