It's nice to give animals fresh treats like those! I don't think your last plant is either plantain or dock. @wholesomeroots explained the plantain identification pretty well. And dock has a long stem on each leaf, before the leaf fans out. I eat dock - it's a good green mixed in with others. Here's a picture of Yellow Dock (Rumex crispus) that shows their long stems:

Borad-leafed dock (Rumex obtusifolius) will have a broader, more oval leaf, but it will still have the long leaf stem.

Looking forward to finding out what that plant is!