Key.to.Soil.Taxonomy.-.Soil.Survey.Staff.pdf

United States
Department of Agriculture
Keys to
Soil Taxonomy
Ninth Edition, 2003
Keys to Soil Taxonomy
By Soil Survey Staff
United States Department of Agriculture
Natural Resources Conservation Service
Ninth Edition, 2003
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Cover: A natric horizon with columnar structure in a Natrudoll from Argentina.
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Table of Contents
Foreword .................................................................................................................................... 7
Chapter 1: The Soils That We Classify.................................................................................. 9
Chapter 2: Differentiae for Mineral Soils anic Soils ............................................... 11
Chapter 3: Horizons and Characteristics Diagnostic for the Higher Categories .................. 13
Chapter 4: Identification of the Taxonomic Class of a Soil ................................................. 37
Chapter 5: Alfisols ............................................................................................................... 41
Chapter 6: Andisols ............................................................................................................. 83
Chapter 7: Aridi