Botany and ethnobotany is my thing. I always suggest, instead of knowing a variety of plant food or material sources, to instead pick two or three general use plants and get to know them well. Many 'wild plants' have high concentrations of vitamins and herbal medicinal potency because they have not been hybridized like the species we grow in our gardens.
Cattail (Typhus spp.) is an excellent starch (polysaccharides or complex sugars last longer) food source with multiple uses. It is an all-around important plant to know and use.... It is found all over N. America.
Manzanita (Arctostaphylos spp.) have edible fruits, the redder the better. I eat the nutty pith. We also grind the berries in meat grinders and make Manzanita cider, an excellent wild beverage utilized by California natives. Also found throughout N.America.
Madrone (Arbutus) has edible berries. Also called 'Wild Strawberry'. Again the redder the better. Super tasty marmalade this one makes.
Rose(Rosa spp.). The rose hips, again the redder the better, even the ones in your garden are used all over the world to make marmalades and are complety. Just don't eat the hairy seeds inside, they aren't poisonous just prickly.
Sheep's Sorrel(rumex acetosella) is prevalent all over N.America. Will be found on pastures, meadows, wooded areas. It is in the sorrel family and has a lemony taste to it, and is another salad green that is both tasty and a scurvy preventative.
Miner's lettuce (Claytonia perforata) is prevalent all over N.America. Completely edible and super tasty salad green.
Stinging Nettle(Urtica dioica) is an excellent food source and medicine. Nettle tea with local honey is what I drink for seasonal allergies. The leaves, steamed or put in soups, is an excellent stomach filler! Will take you far on a hike.
Thistles Pretty much any variety of thistle houses large amounts of moisture in the stem. Think of it as celery. Strip the prickly outer skin and chew on the stem and suck in the moisture. Will also get you far on hikes and prevent dehydration while giving a small jolt of sugar.
There are so many!
Here are some tips:
-go for younger growth, not old leaves, the younger, the more nutrient content and the tastier.
-in the case of berries, the more ripe, the better. Unripe can be sour or cause stomach issues.
-Never over graze the wild foods in your area. Especially your camp. The food in your direct vicinity is useful for attracting animals and used to feed you in case of emergency, say, if you twist your ankle.
-Always leave a third of the harvest
-Getting species prior to bloom or prior to shooting flower stems insures sweeter taste and nutrients.
The flowers of many species also make excellent salad greens. Mustards, and my favorite, dandelion flowers when cooked with a little oil or butter make super tasty fritters. Drying berries and fruits also extends the 'shelf-life'....
A side note: It is both important and fascinating to realize the necessity of tri-chromatic vision. The development of our eyesight was in direct relevance to the fruits, berries and nuts we picked. The riper, the better! But also, colors are indicative of other things: take poison oak and sumac: the red spots almost tell you what they will do to you...
As for insects: I was big on insects for a while. In Belize, I found a hefty mix! Wow! These are some things I can offer as help:
-Cooking, even a little bit, ensures better nutrient intake than eating raw if the insect has an exoskeleton. As with mushrooms, the exoskeleton of insects is made up of tough chitin. As with mushrooms, the nutrients bound in the tough structure of chitin is opened and released with a bit of heat. I always chuckle when I see a excited raw foodist want to plop everything in their mouth raw. In addition, our stomachs evolved with fire and cooking..... A little heat can go a long way....
-Beware of the colors of insects. Colors are indicators. Bright reds and blues, for example. The larval stage (grubs, etc.) has been the tasty treat for eons. Insects have evolved with this fact. Thus, larvae will have protective aspects. Irritating prickly hairs, or for instance, the Blue Morpho butterfly, has blue colors on it as a warning. This is indicative of the excretion of cyanide. Think
'cyan-ide'.