My former neighbors apparently hit hard times - we knew they were moving, but didn't know they gave up their house until the bank signs showed up about a month later. Well either the banks are over-run with abandoned houses, or the branch/team in charge our the house next door are very incompetent, because the yard is almost always thigh high in weeds. But not everything is bad about that, because this poke was allowed to grow big enough for me to recognize it:
But I figured since the rest of the weeds were approaching waist height, the mowers might be forced to return before the house got another city-sticker, so I put a circle of bricks around it. It worked! Hopefully I'll be able to harvest some seeds and root from this poke.
There's quite a few articles online about how to prepare the poke greens before the plant starts showing red, but info about the shoots is still hard to find: Here's a text file about how to force poke shoots in the closet/cellar, and a recipe for Hoosier Poke Sprouts.