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Excerpt:

Consuming wild plants requires a cautiously sensible approach discovering whether you are tolerant to a particular plant, gathering from safe sources, and never consuming anything that has not been properly identified as edible. For safety, don't feed wild foods to minors, eat them during pregnancy and, if you have any medical condition always get a proper medical opinion on whether it is safe for you to try certain plants.

It goes without saying that - depending on what the ingredient is the recipes assume that your ingredients have been washed, gutted, dressed, cleaned or peeled ready for use, and are bug and disease free. Most edible wild plants, particularly those where the rootstock may be eaten, are best before they 'bolt', or flower, and many are worthless once they have flowered. In many plants the stems and stalks often become fibrous a month or two after their initial appearance, and others quite woody as they age.