A reader left a helpful comment reminding me of the importance of practicing stewardship and care when foraging for wild edibles. Also known as wildcrafting- the word 'craft' meaning skilled practice and proficiency- there are crucial ethical considerations that must be employed in order to skillfully and sustainably harvest uncultivated plants, especially from sensitive wilderness areas, so that the plants and surrounding environment are in no way damaged.
Some obvious things to keep in mind include, proper identification and whether or not the plant is an endangered species, or if there are laws against picking the plant. If possible, stick to known invasive species in your area or other 'noxious weeds' that are edible. For instance, garlic mustard, mullein and dandelions are considered a nuisance to gardeners in Ontario. People spend whole days and plan events around eradicating garlic mustard and other 'weeds'. Harvesting these plants for edible and medicinal purposes is doing them a favour.
Also note the environment from which you are harvesting. Avoid harvesting from the sides of roadways, brown land (undeveloped sites where the previous use of the land may have caused contamination), private property (unless you have permission) and protected or other environmentally fragile areas.
These are just the basics to consider when wildcrafting or foraging. A quick internet search yielded many other ethical concerns to keep in mind and there are a number of good resources and articles on the topic.
I found this article on ethical wildcrafting from Henriette's Herbal to be quite informative. Some other helpful articles can be found here, here and here.
Foraging can be a fun and wonderful way to get in touch with nature, increase your local food supply and provide nourishment in difficult times or emergency situations, but it is important to follow ethical guidelines to protect yourself, and the surrounding ecosystem. Always strive for excellent stewardship and best practices to ensure a healthy, thriving environment!