Please identify apple tree?

[Jordan Selsor]

Ok This tree is at an ambulance station in east central Mo. Its safe to say its a crab apple. Any ideas as to what kind and drop time? Think its worth growing from seed or grafting to a hardy rootstock? Tks in advance gents

 

[Jordan Selsor]

 

[Jordan Selsor]

Close shot

 

[Jordan Selsor]

I did taste a couple. Tart but a good tart. If that makes any sense