Weird bumps on grape leaves
I'm growing grapes for the first time, and when I was out mulching them yesterday, I noticed something weird on one branch of one plant. I'm thinking I should just cut the branch off, since it can't possibly be good, but can anyone tell me what it is? The first photo is the branch in question, the next is the grapes from that plant, the one after that is some damage to the leaves on another branch (it was laying on the ground until I tied it up to the trellis just before I took the photo), and the last is the leaf from a completely different plant that I just thought was neat looking.
Thanks in advance for your assistance.