For more than 50 years I've hiked well worn trails over a thousand years old and recently "designed" nature paths...all have one thing in common...human and domesticated/wild animal feces. In the deserts in the Middle East you can find petrified camel dung and, in the waddies companion human waste. No longer do we use our hand, grass or leaves to clean up, but rather the accoutrement's of Vinotinto's Camino Snowmen. Sure in time the paper will bio-degrade, but tissue flowers do not smell as sweet.
Here are a few recommendations from Leave No Trace Camping:
Purists say that "pack it in, pack it out" applies to human wastes as well. But for obvious reasons, most leave-no-trace campers aren't quite so meticulous. Still, this doesn't mean you should relieve yourself wherever and however the spirit (or your bladder/bowel) moves you. Your wastes are not only distracting, but also a potential source of disease.
Urinate at least a few dozen feet from any trails, and well away from water sources used by wildlife or fellow campers. Try to avoid urinating directly on plants, and preferably do it in a spot where it will either quickly dry on the rocks, or be soaked into the soil. Guys: spread it around.
Feces should be buried, at least 200 feet (60 m) from water sources. Use a plastic trowel (weighs less than 3 oz.) , so you can dig a "cat hole" to bury it in, at least six inches (15 cm) deep and wide enough that you won't fill it up. Fill the hole back up and "disguise" it when you're done. Don't try to pretend you're sitting on a toilet; squat all the way down over the hole. This minimizes the need for wiping afterward, because it's how humans were designed/evolved to dump solid wastes. You may find that leaving your pants around both ankles puts them in harm's way; take care. Use (unscented) toilet paper, and either pack it out in seal able baggies or bury it along with the feces.
I didn't consider this, but in for a penny in for a pound:
Opinions vary on whether used tampons and sanitary pads can be buried (most say no), but non-biodegradable tampon applicators should definitely not be left in the wilderness. Women may choose to make use of reusable menstrual products: washable cloth pads will need to be cleaned with soap, but reusable menstrual cups made of rubber or silicon can be rinsed or wiped and cleaned more thoroughly periodically. Blood from the cups should be disposed of in much the same way as feces.
The doctor is Not in!
Arn