I came up with this idea while I was working on my Wilderness Survival Merit badge at horseshoe bend in Texas. There was one requirement where you are suppose to "survive" one night outside with nothing but the clothes on your back and some water. To make it realistic, I made a mini barbed-wire layout so I have protection from medium sized animals. I call it barbed rope!
Step 1: Materials
rope (not string. String is too weak.)
para-cord (stuffs amazing!)
plant roots ( gonna have to be pretty long)
If you know how to make string from long grass or plants, that works too! I think there is an 'ibles on that in the survival skills contest :)