I planted my artichokes last year, they grew to about 2' across and
looked like thistles.

I cut them back to about 8" in height and mulched them thickly (~8")
with hay, over which I laid a piece of black mesh...I figured this
would allow the accumulation of a little extra heat on those sunny but
cold winter days.

The weather here has warmed a bit, so I pulled back the mesh and the
hay...

....to discover that it looks like the plants have withered down to
ground level.

There is still a 3/4" round "stump" at ground level, but all the
leaves are black and they just pulled away with the mulch.

Are they goners, or do they have a chance?

Thanks,
Mark