I have two of these volunteers in the understory of a huge pecan tree.    They are both very leggy and appear to be reaching for the light, but then I saw one in a manicured landscape at an office building in full sun and it's 20 ft tall and also scraggly.    The bark and leaves make me think prunus, the trunk is maybe 4-6" but the multiple flower buds confuse me (easy to do, haha :)    I'm afraid to let it go to full  maturity if it's going to produce a million unwanted toxic seeds!

Prunus seems accurate. Here in Montana chokecherry has those types of flower clusters. Some other prunus species do as well.

Looks like a chokecherry to me too. 

edit:  But getting a berry identification book and verifying would be recommended before you eat them

Thanks guys!   I'm still not 100% sure because none of the google pics or in this webpage show the reddish tinged leaves but maybe it's because they're spring fresh.  I like that my chickens will enjoy the berries.   I quit mowing in that area 3 yrs ago and it's part of my chicken run so I'll just leave these 2 trees alone this year and see what happens :)

http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=c131