[Spunky]

"You can see the duct tape holding the sign."

If your saying that shiny looking stuff at the top of the sign is duct tape, what the heck is it taped to?

That looks more to me like it would be some kind of a clamp, clamping it to a board.
I may be wrong, although you can't tape to air, but pictures are decieving. :-)

[Velveeta]

It's taped to two metal poles (like rebar?)one on each end of the sign.

[clouda]

To me it looks like he taped the sign to some poles, and the poles are stuck in the ground. I see tape on the top and bottom.