A friction fire made by the "Fire Plow" method is not as easy as it looks. Practicing with the right woods and techniques is invaluable to being prepared for an actual emergency. I used dried wild hibiscus wood, which in my experience is the easiest wood to do this with. I've heard that dried sotol wood is also very easy. The Samoans say that any type of wood can be used to make a friction fire, and it's important that both sticks come from the same piece of wood. I've tried many different woods and been successful with amazing amounts of smoke, but thus far haven't had any success in developing a coal. It's probably my technique, which I hope I can master over time, but I've found very little information on the subject, and nobody who's actually done it with wood other than hibiscus or sotol.