My parents on the Heart Mountain Project between Powell and Cody, Wyoming raised an orchard in the 1950s with an apple tree. Apples were crisp, tart and used mostly for pies (some applesauce, some cider). They started falling off the tree in August. I need help to identify the apple variety.
Park County Wyoming
Looks like a good apple! I'm going to recommend talking to Steve Miller at University of Wyoming. He has done extensive work with heritage apples and he started the Wyoming Apple Project. He may recognize it.
Here is Steve's contact information: 307-766-2834 firstname.lastname@example.org
I think the only way to know for sure is to have the DNA tested. UC Davis offers apple variety identification. https://fps.ucdavis.edu/dnamain.cfm
Here is another online tool that may help you narrow it down.
Thanks for the question.