WHEN NATURE CALLS. . . After rowing hundreds of urban North Americans down whitewater rivers, Kathleen Meyer discovered that defecating in the wild without a commode is hardly an innate skill, but a complex procedure desperately in need of a protocol! This sobering revelation, and her subsequent mastery of the artform, has made How to Shit in the Woods the backcountry bible of eco-friendly outdoor elimination options since 1989. Long-embraced by the outdoor community, How to Shit in the Woods is still the go-to primer for backpackers and hikers, campers and climbers, skiers, sea kayakers, river runners, and all off-the-grid sojourners. The third edition presents the latest innovations, high-tech to low-tech, for responsible human waste disposal. Also featured: reflections on the increasing adoption of ''packing-it-out,'' a practice designed to help protect sensitive environments; the most current safeguards against health risks associated with drinking straight from wilderness waterways; suggestions for purists who plan to leave the t.p. at home; and a wealth of recommendations for ladies who must make do without a loo. Meyer's delightfully shameless discussion of a once-shameful activity, her erudite examination of its associated vocabulary, and her unapologetic promotion of its colorful vernacular, make How to Shit in the Woods essential--and vastly entertaining--reading for anyone who has ever paused at the edge of the wilderness and pondered, ''Where do I go to go?''