It is chokecherry (Prunus virginiana). Fruit should ripen black although some populations ripen red. They are usually too astringent to eat fresh but make excellent jelly or syrup, essentially unset jelly for pancakes. Occasionally they hang on the trees for a couple of months without drying out or eaten by birds and after a month of frost they get quite sweet. Probably the most common wild shrub in my area, northern great plains.
Thanks for all of the replies. I will see if they have ripened to a different color when I get up there at the end of September. If they are chokecherries I will take the fruit and plant them in other areas to get a few more growing!