"Yarrow: flowering plant found in the southwest
Use: local anesthetic

Mint: a green leafy plant with a strong scent found in all parts of the united states.
Uses: helps with problems of the digestive tract. the essential oil "Menthol" can be rendered from the leaves and used to treat muscle pain, sore throat, and congestion.

Lemon:Citrus fruit grown in tropical climates around the world.
use: lemonade was originally made as a tonic used to treat chronic migraine headaches.

I am working on a whole section dedicated to this subject for the Global Survival Guide project.
"

"Willow, when brewed has similar atributes to asprin (pain, fever, and BP reducer).

Yellowroot, a terribly bitter plant with bright yellow roots that grows near streams. Painkiller and stomach calmer.

The skinlike bark from a Tulip Poplar: wound dressing.

"

"before your edit you asked about cleaning wounds. use Saline solution (9.0 g salt per liter of water). this should be done with sterile, demineralized water."

"For a basic cold or flu, to get someone moving, throw:
-oregano
-ginger
-mint
-maybe yarrow
-lemon
-sage (it's very common wild)
into boiling water and boil for a few minutes. Done!"