Likely leaf galls. If so, won't affet the tree's health.

Katie,

If the exfoliation is still a concern, -- the bumps do sound like leaf gall -- you might try an ask extension. They usually have dedicated tree boards where a horticulturalist will answer your question. I use U of I.

http://web.extension.uiuc.edu/askextension/

The bumps are galls and, as said, not a problem.

The peeling bark is a potential problem but isn't related to the bumpy leaves. Need more info about the tree, its site, and care to know about the peeling bark. Pictures would definitely help.

Beyond that, call a certified arborist or two for an onsite evaluation and suggested management.