Water is not the most plentiful substance in the Nevada desert, but with a plastic bag and some leaves it can be made.
By digging a hole in the ground, tossing green leaves in it and covering it with a three-foot long clear plastic bag, stranded hikers can make up to eight ounces of water during eight hours of direct sunlight. By placing a canister under the bag, water can be collected for drinking.
The water made in these solar stills can be life saving to someone lost in the hot desert, said Steven Silva, senior law enforcement specialist for Nevada State Parks.
Building solar stills was just one lesson Silva taught at the Wilderness Survival Skills class at Washoe Lake State Park on Saturday.
Silva also taught about other sources of water. Besides springs, there is also water that drips into catch basins after storms.
People can only survive a few days without water, so it is very important to find it, Silva said.
"If you're in the sun and physically active, you could need one liter of water per hour," Silva said.
Because a lot of the water found in the Nevada desert is unsuitable for drinking, Silva explained it is necessary to carry water purification tablets or filters when going into the desert.
"If you drink it and get sicker you'll accelerate your dehydration," Silva said.
Besides being prepared in the desert, Silva said it is important to remember why you want to survive. He said people without tools have survived just because they didn't want to die.
"The number-one thing you need is a positive attitude," he said.
Silva also spoke about food in the wilderness. Although people can live for weeks without food, some plants are edible. One of the ways to determine is by the way it tastes. If it tastes bitter, Silva said it is not safe to eat.
But there are other sources of food in the desert, besides plants.
"You can eat any little furry mammal you can capture," he said.
About 10 people gathered at the park to learn survival skills. They were also provided with survival kits, which included waterproof matches, candles, a fishing pole, baggies and a whistle, among other things.
The survival skills course is held once every summer, said Park Ranger Donna Silva. It is just one of the seven programs offered at the park.