Dark,
I agree with you wholeheartedly on the notion that we are living in troubled times. Strange days have found us..

Although I do not personally know
alot about botany and the useful plants in your area, I know a bit about the ones around me, and I do believe that you are on the right track as it is
far better to be prepared than to wait until the last minute.
The first thing that would help us help you in your quest would be to give us a little detail on the climate area that you live in, whether it be
alpine, temperate, tropical, or any other, since most vegetation is limited by area, topography and seasonal changes. Stuff that may be abundant where
you live might not flourish in other areas, so that is very important.
Here are a couple that I am used to: (disclaimer... use at your own risk)
Cattail:
Chopping the root of the cattail and applying to minor cuts and burns can provide remedy for light abrasions, or grinding the root and boiling into a
steep (or stew) may help gastrointestinal problems, like diarrhea or worms/
Dandelions:
Very common in the many parts of the globe, this common lawn pest can be used for a variety of things, such as; Root of dandelion tea was used as a
laxative, diuretic and laxative, and it may be used to rejuvenate the liver (speculative) and aid in digestion and improve appetite.
It just all depends on your surroundings and what is abundant near you. Research, talk to the locals, remember that the elders were doing this long
before us. This is pretty much my first post in the survival area here, so take it as what you will.... and hope to see you around.
Good luck in your search,
T.