I'm trying to remember what my mom used to harvest from the roadsides. Poke, dock and ??? Darned if I can remember. I do remember she would boil the stuff, and drain off the first water, then boil again.
Dandelions! Dandelion tea, jelly and wine from the cheerful yellow flowers. The young greens are good in salads.
@so lucky it was probably poke. I have picked poke and cooked it, it is quite good. You have to bring it to a boil twice, pour off the water and the third time, continue cooking. They are tender, tasty greens.