i use the US Army survival guide. free on android.....and it has one of those app things
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Short of joining the army getting through basic/AIT/Jump school maybe ranger school and completing the Q course, This book is awesome and there is an iPhone app for it as wellSAS Survival Guide by Lofty Wiseman is a good basic book. You can get a pack friendly condensed version. The Petersen's Field Guide to Wild and Edible Plants: Eastern and Central North America, the Tom Brown Series, plus all of the recommendations that the other members have made, especially the Wilderness Medicine book recommended by Chris Mac.