I found an apple tree in with some other trees maybe 50′ off of the road. It does not have a large trunk so I don’t think it was something deliberately planted as this land has laid fallow for 30+ years and I have owned it for 11. I assume it was the result of an apple core that someone (maybe even me) threw in the brush beside the road. It already has apples showing on it. I’m cutting away the wild grapes that are growing on the tree and trying to prune back other things around it so it can get more light.
I have planted a few apple trees (2 Honeycrisp, 1 Gala) this year and plan to add more in future years. Apples do much better if they have other apple varieties nearby to cross pollinate. So I will be watching next spring to see if this wild apple is in flower at the same time as my cultivated varieties. If that apples are less than desirable for human consumption they can always go to the chickens and deer.
You can plant a crab apple to serve as a pollinator for the eating varieties of apples, but is still have to be in bloom at the same time. the other apple trees. However crab apples tend to bloom for longer periods of time so this lets you cross pollinate more trees with just the one crab apple. Another research project for the winter, find a crab apple with the longest bloom time. Plus my bees will like it.