I’m hesitant to diagnose the tree with so little information. The long green bumps make me think you have one or more kinds of insects that produce galls.  The yellow and brown leaves could be Dutch elm disease. If it’s DED you’ll want to either burn or bury the tree. However, it would be wise to take an infected branch to your local extension office and let them examine it.  The Cuyahoga County office is at 5320 Stanard Avenue, Cleveland, OH 44103; phone<personal data hidden>.

For more information and some pictures that might help you further determine what’s happening to your tree, you might want to look at the following websites.

http://extension.psu.edu/pests/plant-diseases/all-fact-sheets/elm-diseases

http://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/pests-and-problems/other/galls/galls-on-trees.aspx

http://www.na.fs.fed.us/spfo/pubs/howtos/ht_ded/ht_ded.htm

It looks like the bumps are galls. Galls can be caused by insects, mites, bacteria, fungi, or viruses.  Since there are areas that may have been nibbled, it’s probably an insect. The good news is that it may not look especially pretty but it won’t harm your tree since it seems large enough to host a few bugs and still photosynthesize.  Chances are a natural predator will control the insects. Since it’s possible that the galls contain future insects, you might want to rake any fallen leaves and get rid of them.

I’m not sure what’s causing the yellow and brown leaves. It may be bacterial leaf scorch or Dutch elm disease or that all the rain we’ve had this year is suffocating the roots.  I’d recommend reading http://www.na.fs.fed.us/spfo/pubs/howtos/ht_ded/ht_ded.htm  for a more detailed description of the three most common possible causes and how to identify them.  If you have a nursery in your area with knowledgeable people on staff you may wish to take a branch to them. Of course, a certified arborist or your local extension agent is your best choice.

The first two pictures definitely look like finger galls. The third picture shows that some insect had an excellent dinner on your tree.  The following websites show pictures of elm leaf beetles and their larvae as well as a little information about them. While they're not the only insect that could produce that damage, they are a possibility. You could look at the pictures and see if you’ve noticed any of them around your tree.

https://extension.umd.edu/hgic/leaf-beetles-trees

http://utahpests.usu.edu/ipm/htm/ornamentals/ornamental-images/ornamental-insects/id=1564/gid=652