Say I'm hiking outdoors and I get a scrape. I've forgotten my first aid pack, or already used up the appropriate supplies. Is there anything in the wilderness I can use to sterilize and perhaps cover it?
There are many folk and wild remedies you could learn, depending on what you're carrying & where you're hiking. Some examples:
Honey will protect from infection.
Spider webs will stop bleeding (for small cuts).
Common plantain soothes burns, scrapes, etc. Chew it up to make a salve.
As yucky as it sounds, if you dont have ANY water or anything to clean the wound, assuming your healthy and dont have any "plumbing problems"(instructions from an ER doctor / paramedic) urine is 100% clean right out of the body.
These are the words straight from the doctor: "pee on it."
Might be a good idea to re-wash it out as soon as you can.
But urine works nicely.....
Wilderness medicine protocols taught by the major Wilderness First Aid / First Responder training companies (and subsequently adopted by most outdoor organizations) are fairly standard and quite clear about wound management in the back-country.
The standard accepted practice for treating a wound is:
Simple, straight forward. And you can do it without any specialized medical kit.
All bandages provide you is a sterile method for doing the last - but in lieu of sterile dressing, any clean barrier from dirt will do. (ie, a clean shirt)
Adding any kind of substance (ie, honey, plant poultice) is generally frowned upon in wilderness settings as these can introduce sources of infection, become breeding grounds for bacteria, or at the very least make it difficult to monitor what is going on with the wound.
If you are far enough away from higher care that infection is a concern, then these "home remedies" are generally considered more risky than helpful, and add one more thing you have to clean out of the wound later.
I keep a few wet naps (like you get to wipe your fingers at a chicken & ribs joint) mainly to wash my hands (do you know how hard it is to wash your hands in the bush?), and have used them to wipe some pretty serious scratched (they are also excellent fire starters). Hand sanitizer would be another option.