Water is the most important thing if you are stuck in the wilderness. Sure, food is important too, but you can live for a while without it; you can't survive more than a few days without water. Unfortunately, in many environments there is either a lack of water, or the water is unsafe to drink. Fortunately, there are often plants. When plants absorb water from the ground they filter out many impurities, and you can extract this clean water from them. Plants transpire water, meaning that water vapor evaporates from the leaves, and this water can be collected. The great thing is, this process doesn't harm the plant and can be repeated over and over again on different branches, and works relatively quickly.
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Step 1: What You Need:
- A plastic bag, preferably clear (check the bag beforehand to make sure it is free of holes. If not, seal them with tape.)
- A plant (I will go over what types of plants work best in the next step)
Step 2: Choosing the Plant
- The best types of plants are those with large, green leaves. Berry bushes also work well. There is a conspicuous lack of trees in my back yard, so I used a blueberry bush. Avoid toxic plants!
- Select a plant that receives a good amount of sun. The heat from the sun will speed the transpiration process.
- Choose a branch that has a large number of healthy leaves; give it a shake to dislodge any insects or debris that might be on the branch. Place your plastic bag over it. Tie it very tightly; you don't want any water vapor to escape during the process.
- Make sure that part of the bag hangs lower than the point where you tied the bag to the branch. Water will run collect there.
- You will want to have several bags up at once, since one branch doesn't provide enough water to live on.
Step 3: The Process
- It will take about 3-4 hours in sun to get a decent amount of water from the plant.
- After about 30-60 minutes water will begin to condense on the sides of the bag.
- After another hour or so much larger droplets should form. These will start to run down the sides of the bag and collect in the lowest point.
- You should get at least 1/3 a cup of water after 4 hours.
- Before drinking the water pour it through some fabric like a t-shirt to filter out anything that may have fallen into the water.
- Reattach the bag to another branch and restart the process.