help with tree ID?

[booboo]

Usually I'm pretty good with this stuff but this one has me stumped. It's on a friend's property, at the edge of an old cow pasture being slowly converted to a perennial garden. They thought it was some type of hawthorn, but the fruit is not red and the leaves are just slightly serrated. The twigs look like an apple/crabapple but the fruit is soft and fleshy. There are some native viburnums that get pretty big and develop into a small tree but the leaf and fruit arrangement is wrong. And it does have a few hawthorn like thorns up in the middle of the tree but not many. Am I overlooking something obvious?? Sorry for the poor quality of the leaf/twig photo, the camera has an autofocus feature that I can't figure out either...

 

[Toddppm]

If it has thorns it could be a Buckthorn?

 

[WolverineMarine]

wild guess here

I went looking through my national audubon society tree ID book..and from what I could see.. if the 1st pic the flowers had 5 petals and were rounded..it looked like possibly a sweet cherry...

 

[booboo]

Well...crap...that was quick. I'd agree, common buckthorn, Rhamnus cathartica. I remember learning about that one in school but the buckthorn lobe of my brain turned to mush long ago. Thanks!

 

[Toddppm]

I can't pretend to know anything! I looked it up in my Audubon book too because I was curious. Don't think I've ever seen one in person or if I did I didn't bother to ID it.
Amazing to keep seeing new trees and plants every day that I just pass over most of the time.