If you are out hiking or backpacking and you run into trouble by running out of water, don’t panic. The best thing that you can do is use your head. Your top survival concern needs to be water, because you will perish without it in only a couple of days.

The old idea of cutting off the top of a barrel cactus is apparently not as helpful as the old tales would have us think. According to John Annerino, outdoor education instructor and photojournalist, he only succeeded in getting about a mouthful of juice out of a cactus after hacking at it for over an hour. That’s not a very good “effort to result” ratio. Besides, what if you run out of water in an area without any cactus?

According to Pal Green, U.S. Air Force survival instructor, the best way to collect water is by making a “transpiration bag.” A transpiration bag is a plastic bag that is tied over a tree branch or the branches of a bush. Amazingly, you can collect a lot of water this way. He collected a cup of water in about a half an hour from a tree that looked pretty much dead. This is not necessarily a common result. You can, however, usually count on at least one cup every four hours.

To create a transpiration bag, tie a plastic bag around a tree branch or bush. Plants with a large root system apparently work the best. Be sure it’s in direct sunlight. It’s important to tie off the bag as tight as possible, so that it’s basically airtight. If you put a piece of paper or fabric around the plant at the opening of the bag to act as a gasket, it helps to seal the bag tighter. Then weigh down the top of the bag, the opposite end from the opening, so that it can collect the water. You can use a rock tied to one of the corners of the bag to achieve this. The water will collect in this part of the bag, when there is enough, simply slip the bag off the plant and help yourself to a cool drink, courtesy of Mother Nature.

Source: Adventure Magazine, Survival Mindset, Wilderness Way