No idea but the thingies on the leaf itself look like galls and shouldn't be used for identification purposes.

Agree that leaves seem to have galls, but the leaves and seed pods remind me of lantana....

J. M. Snyder has been asking about this plant on several sites!

The galls on the leaves, the leaf morphology, and the berry/fruit conformation make me think Common Hackberry - Celtis occidentalis.

If more images were provided of more of the plant, then this would be easy to nail down.

The berries look unusual for CO. I can't find any photos with shriveled berries like in this pic. What other sites?