Disclaimer: This article is meant to be a quick overview and not a detailed guide on identifying and consuming edible plants. Seek guidance from a trained botanist before attempting to eat any plants. Any attempt to consume plants shall solely be at the reader’s risk.
For those familiar with tropical survival techniques, you already know that water-rich jungle climates are home to many species of vines and plants that yield safe drinking water. But what happens if you find yourself in North America, staring down the barrel of dehydration? With only your surroundings as a resource, can you stay hydrated from plant water sources?
You’ve seen the cartoons. Just chop the top off a cactus and it will be full of drinkable water. The only problem is, we’re not in a comic book and that cactus is full of bitter, gelatinous pulp. There’s a myth in the survival community (likely started by disillusioned cactus choppers), that you can only extract drinking water from plants in tropics. But that’s not true.
Tap a Tree: In late winter and early spring, numerous trees produce drinkable water. Tree tapping is a simple operation, if you get the timing and the species identification right. With a knife, drill, or similar tool, bore a hole into the tree trunk. It should go through the bark and a few inches into the wood. Insert a tube or some other item to channel the sap flow into a waiting container, and wait for the sap to start dripping. It typically flows best on days that are above freezing that follow a sub-freezing night. Try different tree sizes and locations of your chosen tree species.
A young strong tree may produce more sap than an older tree. It’s also best to tap the sunny side of the tree, above a large root or below a large limb. In mid to late winter, sycamore trees (Platanus spp.) will have a very irregular sap run. These trees are found in the east, as well as California and Arizona. In late winter, you can also tap maple trees (Acer spp.), which are found throughout the country. Maples can produce heavily; up to a gallon per day per tap during the peak of the sap run.
Walnut (Juglans spp.) and hickory (Carya spp.) will produce around the same time as maple. Birch (Betula spp.) is typically the last tree to have a sap run. Walnut, hickory, and birch species are found throughout the continent. But a word of caution, don’t drink any sap from unfamiliar trees. There are more than a few toxic trees in North America. Use a field guide!
Slice a Vine: After the sap run ends in usable trees, you have another chance to collect sap for drinking water. Grape vines (the genus Vitis) can be used on warm spring days. Chop the vine on an angle, place the pointed end into a container and collect the water. Due to the higher tannic acid level and low sugar content, grape sap will taste a little bitter and astringent, but it is perfectly drinkable. Vines less than a ½ inch in diameter will drip for a few hours before they stop, while larger vines will gush water like a faucet. Like tree tapping, this is all about timing. There’ll be days when the water will flow, and days when it won’t. You’ll only know for sure when you try. Again, make certain that the vine really is a grape, as there are some toxic vines with sap that wouldn’t be safe to drink.
Boil Down Syrup: If you’re lucky enough to have trees producing sugary sap you can boil off the water to make your own syrup. All of the trees mentioned in this article can produce sweet syrup (except the grape vine). Maple has the taste you already know and love. Hickory is similar, with a hint of pecan. Walnut is sweet, with walnut essence. Birch and sycamore have their own special flavors. One quart of sap will boil down to a spoonful of delicious syrup. This is well worth the trouble, especially if you have a fire going anyway for warmth.
Berries as a Beverage: One frequently overlooked source of hydration is the juice from edible berries. Blackberries, raspberries, blueberries, mulberries, and other edible berries are found throughout North America. These edibles are at their most plentiful in the summertime and ripe ones have a high water content. You could, of course, eat them for solid food and moisture. But when you lack water, it’s not wise to eat anything. Digesting food and passing waste are both processes that require water. Your best option is to positively identify the edible berries, wrap them in a piece of clean cloth, crush them and wring out the juice. This juice will provide much needed hydration, with accompanying sugar, vitamins, and minerals.
Claim the Cactus: Remember the cactus pulp we discussed earlier? It’s not completely worthless. If you’re able to improvise some distillation equipment, the cactus pulp can be added to your other raw water sources. Whether you’ve built a still from a vessel and some condensation coil, or you’ve dug a solar still pit in the ground, cactus pulp will increase your water output. Use a local plant ID guide to ensure that you’re not using any toxic greenery.