Soils Honor
Wikibooks Soils Honor Answers

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 Do you like playing in the dirt?  Have you always wondered why some dirt looks bright red and why Georgia clay sticks to your boots?  This honor, Soils, will explore the exciting world beneath our feet by learning how soil is made, how it varies around the world, and what it is made of.

 - Soils Honor
 - Soils Honor Answers

Soils series (for Soils Honor and soil science studies)
http://soildatamart.nrcs.usda.gov/