I have ruled out wild cherry and Hawthorn, this is the only tree/shrub of it's kind in the area. I live in Central Nova Scotia (Stewiacke)
Well, it looks like a Hawthorn to me. Crataegus x persimilis or something close. What makes you think it is not a Hawthorn?
Looking at your example it might be a Hawthorn, the Hawthorne variety I saw the leaves were not like my pic and the tree has no thorns on it, but looking at your link definitely changes my view point. Thank you.
You have a very good eye, I had to zoom in on that from 75 feet, it's in an area that is surrounded marshy growth.