Toller wrote:
I have to replace some low retaining walls. The wood is easy because its
all rotted away, but I can't get the rebar that held them out. The ground
is shale, and doesn't want to give them up.

Any magical solutions? I thought of an auto jack, but don't see how to grip
the bars.
Driving them in rather than reusing them is a solution, but driving them a
foot into shale is a real chore!

I'd try the pulling as others suggested (my suggestion would have been
the same except they beat me to it) and if it works, good, but if it
didn't or was particularly difficult, given the cost of rebar I'd just
take the torch and cut 'em off...

If you have one or access, what I use as a puller for such things
including fence posts, etc., is either bucket or the 3-pt depending on
access or how much actual lift needed...