Well, maybe they're not ALL good, but some are edible, healthy, and useful!
When Dave and I took our camping/wilderness class, we learned about so many great plants! Here's a quick run-down of the few we learned:
Dandelion: the leaves, while bitter, are great for liver cleansing! "Back in the day" (love that cliche!) people would go and actually buy medicines called "Bitters." Many green plants that have a sharp, bitter taste are good for you! The yellow heads can also be made into salads and honey! People are starting to recognize the benefit of dandelion now, so you may actually be able to find the greens in the store! But they are huge, full-grown leaves. One of our instructors said the smaller, more immature leaves are less bitter. I haven't had enough experience to be able to experiment the tastes, yet.
Purselane: I'm not sure of the specific nutritional value of these, but I know you can eat them! We chopped them up, heated them, then melted a ton of pepper jack cheese in it (shhhh! I know, not healthy!) and used it as dip for Triscuts at camp! So yummy!
Plantain or Plantago: (The flowery plant, not the banana-like fruit) well, ok, so this one is good for reasons other than nutritional sustenance. Plantain stalks are natural mosquito repellents! Eat three stalks per day for three days, and your body will start to naturally produce a repellent! Will it also repel those around you? I don't think so, but keep an eye out for friends inching away, and let me know ;-)
Jewel Weed: Dave's favorite! The thick stalks contain an aloe-like gel that you rub on itches! Specifically poison ivy, but it can may also help relieve other irritants.
Wood Sorrel: Dave calls this one "God's candy" as it has a slight lemony zing to it, and grows in abundance :) We also found this at one of the parks we have visited. Sadly, I didn't trust the park to be fertilizer-free, so we could not eat them. But they grown like crazy in our back yard, and I've seen a few sprouting this year! So maybe I'll season a salad with some lemon kick!
What a wonderful Provider we have! Such healthy, useful products within our own yards - and darn near impossible to screw up the growing!
Here's the kicker though: you can't usually rummage around fields to eat this food because we're trying to kill the weeds with weed killer! Poison on our bountiful health! Sadness!
If you don't treat your lawn with fertilizers or pesticides, and you're not near a roadway where lost of car exhaust will pollute your yard, you just may have a feast awaiting you! On the last day of my camp, we were given some instant rice, and told to add what we wanted to it. I went out and hunted up a bunch of green leafy dandelion leaves, jewel weed leaves, found a few wild carrot roots and onions, and tossed in a handful of wood sorrel for a hint of lemon! I turned that boring rice into a lovely grain salad!