In a git repository, a remote branch I am not tracking was deleted. When I type
git branch -r
If you perform something like
git branch -d -r remote_name/branch_name
you only remove your local checkout. This command doesn't do anything to the remote repository, which is why it still shows up.
git push origin :branch_name
will remove the the remote branch (note the ':'), and
git branch -d branch_name
will remove your local checkout.