I'm gonna love this thread.
Some survival tips I've learned:
The juice of a fiddlehead, and the spores of a young fern act as a minor pain suppressant; they act great as an emergency pain reliever in case you get stung by a stinging nettle.
Why would you be stung by a stinging nettle? Stinging nettles are a super food, and when you boil them, the venom is disabled. You can eat them just fine, then. They are delicious and full of nutrients.
Cat tails make excellent food if you come across them. The pollen can be used like flour (for, say, pancakes and things like that), lower leaves can be used for salads, the young shoots can be eaten raw or cooked, and the young flowers can be roasted.
Queen anne's lace is a wild carrot, and the flower bundles can be deep fried to make fritters (using cattail pollen, if you like). Just don't mistake it for poisonous hemlock or yarrow, which they look very similar to. One way to tell the difference is to break the root in half and smell. The queen anne's lace will have a strong carrot smell, and if the root is young enough, that is edible, too.
Chicory root is great for bush coffee, if you need something to drink. Clover flowers are also great for teas, or they can be eaten raw like they are with the leaves.
I remember that Dual Survival show when they tried to survive in the Olympic national forrest, and failed. It's easy to survive here, as there's plenty of food and kindling for fire (but they got rained out). You just need to have a little specific education for the area, first.
Edit: Oh! Also, some strains of dandelions are edible (you can see their leaves even in some salads you buy in the store, like spring mixes). They were originally brought from Europe to the Americas during the settling process, because they weren't sure there was edible food to eat here. Since then, they've spread like wild fire.
Camas is also an edible root plant, but only before it's flowered (much like queen anne's lace). The first people's of the pacific northwest ate this food often. Problem is, death camas looks very similar to the edible kind before it flowers, so I definitely do not recommend trying to eat that one unless you are a trained expert.