Curly Dock, (Rumex crispus), is very common on our farm. I found it was edible in Sam Thayer’s second book, “Nature’s Garden.” I was excited to try it, because its been a long winter and this plant starts growing even earlier than Stinging Nettle.
Sam recommended cooking it, and I concur, or possibly using it raw as part of a salad. It’s a little too bitter for me to make it my entire salad. I eat eggs nearly every morning and it’s a welcome addition, as pictured below.
Besides wild berries, I’ve only been learning and eating wild edibles for the past eight years, inspired by Sam’s first book. Something I’ve learned is that even though I’m an adventurous eater, I need to try something a few times to get a taste for it. By the next year when the plant is ready for harvest, my taste buds, or brain, or something, is primed, and I’m looking forward to enjoying it for many meals.
Curiousfarmer 
“When leaves are young, they are edible and nutritious as cooked greens, but only in small amounts because they contain soluble oxalates that can be toxic in certain quantities.”
Thank you, Stan. What do you mean by small amounts? Is the serving of Dock with eggs in the plate above a small amount?
Yes, I read that Dock contains oxalic acid and there has been one death attributed to it. I did a little more research and found this site which has a chart showing the different amounts of oxalic acid in many plants, including dock: http://www.eatthatweed.com/oxalic-acid/
You’ll recognize most of the plants on that list. Most or all plants have toxins, maybe its a defense mechanism to avoid overeating.
The way I approach wild edibles is to use taste and moderation.