Ideally, you have a tent and a sleeping bag. Failing that, you ought to have basic emergency supplies (see Survival in a Bag), including a plastic drop sheet and some parachute cord that you can use to make a simple A-frame tent. But even with no supplies at all, you can still build a basic debris shelter.

First, choose a dry location with plenty of sticks, leaves, and grass around. Next, find a ridgepole—a fallen tree about 12 feet [3.7 meters] long—and a standing tree with a branch a few feet off the ground. Rest one end of the ridgepole in the crook where the branch extends from the trunk (use a rock or stump for a support if you can't find a low branch), then line the pole with sticks, each about a hand's width apart.

After crisscrossing these poles with small branches or thick grasses, cover the completed framework with a thick layer of boughs, more grass, and leaves. Generously cover the ground and pad the interior walls with leaves or pine needles, then slide inside and use boughs or your jacket to seal the door.

Survival specialist Mark Morey once safely spent the night in a debris shelter while a hurricane destroyed his store-bought tent, which was set up nearby. "It was snug and quiet in there," he says.

Workshops with Morey's Vermont Wilderness School (+1 802 254 1007; www.vermontwildernessschool.com) cost U.S. $250 and up.

—Laurence Gonzales

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