More information is needed for a positive identification of this plant. For instance, has it flowered and were they racemes with white flowers? Do the leaves and green twigs produce a bitter almond smell when crushed? Were berries produced? If so the the plant may be a chokecherry. Other possibilities based upon the photos are mulberry or possibly a serviceberry.
May I suggest checking those plants online at edu.com sites for more information or perhaps taking a sample leaved branch to your local cooperative extension office for additional help.