In Debra Granik's Leave No Trace, a father Will (Ben Foster) and his daughter Tom (Thomasin Harcourt McKenzie) create a home for themselves in the wilds of Portland's Forest Park. While they buy provisions on periodic runs into the city, they mostly live off the land, growing food and foraging. "Tom and Will are part of a subculture built around the preservation and practice of primitive skills," explains Granik. "Honing outdoor survival skills comes with an ardor for keeping alive things that our ancestors knew how to do." Foster explains how he and McKenzie trained with wilderness living and survival skills instructor Dr. Nicole Apelian on "how one lives off the land, making camp, and how to disappear in plain sight." To honor Will and Tom's spirit, we have assembled a primer on foraging in the wild, including a few quick recipes that might save your life.

As with haute cuisine, putting together a survival menu depends on your culinary prowess. In Primal Survivor, Jacob Hunter has created a "Pyramid of Wilderness Survival Food" to chart how your individual skills should determine your food choices. Putting simple foraging-"wild greens, berries, fruits, tubers, roots, shoots, and flowers"-at the base, Hunter's pyramid rises up five more levels: (2) nuts, seeds, grains, and insects; (3) fish, seafood, and eggs; (4) reptiles, amphibians, and mushrooms; (5) birds and small game;" and finally (6) large game (like elk, deer, or wild boar) at the top.

Foraging for your life

With a basic knowledge of wild flora in your area, a bounty of edible plants is available to you in the wild. Of course, your choices will change by region and elevation. The Southwest's prickly pear cacti and piñon nuts might be a little difficult to find in the forests of the Pacific Northwest. When Dr. Apelian, an advisor for Leave No Trace and a contestant on the History Channel's Alone, chronicled the 26 items she ate during her 57 days on Vancouver Island, at least 14 of them were foraged plants. The benefit of harvesting simple produce, like grasses, berries, and apples, is that that many can be eaten fresh or mixed in a salad. Other items can be made edible with simple cooking. Like with all wild items, it's essential to know one plant from another so that you don't mistake wild tomatoes (tangy and sweet) with horse nettle berries, which, according to Mental Floss, cause "fever, vomiting, diarrhea, and occasionally death."

If you don't know what a specific plant is, Sky Above Us provides a list of things to watch out for including: "Milky or discolored sap," "'Almond' scent in the woody parts and leaves," and "Three-leaved growth pattern." But there are few common plants, like cattails, burdock, dandelions, clover, and thistles, which can be your go-to groceries in the wild. Dandelion leaves not only make a great salad, but you can also prepare the roots. To prepare, wash the roots, peel them, and cut them into button-sized pieces. Boil for about 10 minutes. Season and, if you have it, add butter.

Insects aren't just for swatting anymore

As you move up your survival pyramid, insects provide an easy source of protein. But unlike many foraged plants, insects need to be roasted, if simply to eradicate possible parasites. With so many buzzing and burrowing about, the real question is which ones should you catch. Popular Mechanics' Jay Bennett offers some helpful basics: "Don't eat anything venomous. If it has a stinger or bright colors, leave it alone." He adds, "If the bug instead has a crunchy, chitinous exoskeleton, like ants, termites or crickets, you can dig in." To cook insects in the wild is really quite simple. To roast grasshoppers, first remove the head and wings, then clean out the inside with a stick, then cook the body on a skewer over an open fire until it is brown, crunchy and delicious. Salt immediately after cooking (if you have it). Field & Stream offers a handy video tutorial on "How to Cook and Eat Grasshoppers."

Cracking nuts, grains, and mushrooms

While leafy and tuberous plants can be harvested fairly simply, grains, rice, and nuts require more knowledge and preparation. Mushrooms demand absolute mastery since most don't live to learn from their mistakes when they pick a wrong species. While acorns can be harvested off the ground or from the branches of oak trees everywhere, they are not exactly a ground-to-gullet item. Be sure your acorns are not horse chestnuts or buckeyes, which are poisonous. To prepare acorns, first test them in a bowl of water. Any nuts that float should be tossed since they may well be infested with worms. Next, dry them out in the sun for a few days before shelling, which is best done with any large available rock. Finally remove their tannic acid (the stuff that can make them bitter) by boiling them for five to ten minutes, draining the resulting dark water, and repeating until the water remains clear. The amount of tannic acid is usually determined by the type of oak, with White and Emory having the least and Red and Black the most. Now you can roast them or ground them for flour.

Small creatures everywhere: fish, fowl, amphibians, and rodents

Unlike insects, these creatures take some skill to get a hold of. If you are by a river or pond, you might be able to catch a fish using a hook and line. But many survival experts recommend constructing a simple fish trap, which frees you up to do other things. Survival Skills demonstrate how to create six different rudimentary traps with sticks and mud. You are not likely to down a bird throwing a rock, so to catch them, as well as rodents, you'll need to learn how to make simple snares. You can, however, climb a tree to harvest bird eggs. If you resort to nest robbing, always leave two or more behind, so the bird will continue to lay new eggs.

A nimble, hungry hunter can catch a frog by hand, either by sneaking up behind them or using a flashlight at night to blind them. While most frogs are edible, it is best to avoid those with bright colors, like orange or blue. To prepare, cut off the feet, and then snip a line through the skin around the abdomen. Pull the skin off over the legs (as if depantsing them), then sever the legs from the body and wash carefully. Some guides suggest opening up the frog's inside to confirm it is healthy. You can boil the legs or skewer them on a spit to roast them over a flame. Just be sure they are thoroughly cooked.