My ‘mountain’ grandmother would make “creasy greens”, also considered by the family to be fine eating. By the time I came along, she was too old to go out looking for them, but I’ve heard stories from my dad about those creasy greens his mom used to make. Since it was one of the earliest greens, after a winter of eating canned food, creasy greens were a very welcome addition to their diet.
From the link http://davesgarden.com/guides/articles/view/2352/
“So, what ARE creasy greens, really? The botanical name is Barbaraea verna; they are a mustard in the Brassicaceae family. Creasy greens are a small leafy green often known as upland cress, winter cress, and early yellow rocket. They are similar to watercress in taste but do not grow in bogs the way watercress does.”
I did once plant a couple of “mustard spinach” seeds but not there and they didn't come up. Making me wonder.
Also have something similar to dandelion, but has white flowers - clusters of tiny beads. Didn't plant anything like it either.