When doing urban foraging there are a few things to keep in mind. It is illegal in some areas to uproot, collect wild plants so please check first. Find out whose property and get permission first, a pant is the property of the landowner even if it is a weed. Above all make sure you know what your harvesting and that it is not poisonous.
On the etiquette side of things remember if there is very little of the plants you are foraging for leave enough for continued growth for propagation and future harvesting. Respect the environment you are collecting from leaving it undisturbed as you possibly can. Avoid harvesting plants from areas that have been recently sprayed or areas that have signs of diseased, wilted or dying plants. Never consume wild plants unless you are positive of its identification and safe for consumption.
It is best to test yourself with small amounts of consumptions at first when foraging to check for hypersensitivity to see how well you body adapts to changes in diet. Never eat large amounts of anything until you test your tolerance to it, everyone is different. Also be conscientious of any water supplies near by for possible contamination and pollutants.
Along with your well known dandelions, nettles, chickweed and thistles that you can survive on we are going to talk about some others and their preparations that are often found in urban environments.
Borage is more of a cottage or herb garden scape, it is an annual or biennial and has distinctive bright blue flowers. The upper part of the plant is rather bristly so be careful if you have sensitive skin, it has a nice cucumber flavor and dipping the leaves and young stems (with bristles stripped off) into batter and frying them for a taste treat. Traditionally the flowers were put into drinks, wine and vinegar for added flavor.
Greater Burdock has large sort of kidney shaped leaves while the lesser burdock has more triangular shape leaves. Roots of these plants are the best part to use. Cut the roots into small shreds and stir fry for 20-30 minutes or until tender. Use either end of first year roots or at the start of second year.
Goosegrass is an annual climber. Use the very young seedlings and the older little tuffs of upward pointing leaves make a tender cooked vegetable. Seeds can be used as a coffee-type substitute, make sure they are purple in color, do not use when dead and brown.
Ground Ivy is a part of the mint family which makes a good flavoring for soups, stews and beverages, consequently do not mistake them for the true ivy plants.
Hairy Bittercress is a waste ground weed with small white flower and makes for a very good emergency food source.
Cuckooflower is usually found in damp moist habitats and is one of the first spring flowers to emerge. They make for great salad usage and can be cooked as well.
Hedge Garlic being a biennial and forms a ground hugging rosette with kidney shaped leaves the first year of growth while during the second year it produces a small cluster of white cross-shaped flowers. Young leaves make a taste salad addition while older ones are better cooked.
Winter-Cress a wonderful perennial that has small cross-shaped flowers with yellow petals forming on the flower stems and grow to approximately 2ft tall. They are usually found in damp soil areas. Young leaves are best and bitter with age. Young leaves make a good salad item and older ones can be cooked as a vegetable with a slightly more aggressive hot flavor than watercress.
Beech trees are common in urban parks and wooded areas. The young leaves are very good in salads and the nuts are good raw or lightly roasted or pasted for soup thickeners, after you scraping he outer brown skin covering.
While these are a few examples of urban foraging there are many more edible plants and with out 100% certainty of what you are harvesting never eat it. If you are new to foraging it is better to have a plant identification book to cross check species verification before consuming. With so many things going on in the world today causing such uncertainty, foraging and plant identification is a great hobby that would build confidence in being able to take of your self and family should disaster hit. It could be a great quality time family endeavor to do plant identification and foraging outings at no cost.