What Makes Soil Good ò Analysis of soils assists an agricultural land brokerage professional estimate the economic potential of the land 3-1

Objectives ò Identify macro and micro nutrients in soil ò Soil texture, structure, and consistence ò Identify horizons in soil profiles ò NCRS capability classification system ò Resources to analyze agricultural property 3-2

Important Concepts for Soils Analysis ò Four major components of soil ò Mineral components develop from parent material ò Organic matter ò Ingredients that make soil solution ò Biological Activity ò Plants draw six macronutrients from soil 3-3

Important Concepts of Soils Analysis (cont.) ò Trace elements or micronutrients ò N-P-K designation for fertilizer ò Soil deficiencies develop from shortages ò Characteristics of soils ò Texture depends on individual particles ò Structure groups soil textures 3-4

Establishing Soil Texture ò Coarse soils - loose and very friable ò Moderately coarse soils - hold together when moist ò Medium soils - feel velvety ò Moderately fine soils - form clods ò Fine soils - form hard clods 3-5

Soil Structures ò Four distinct structures ò Platy soils - flat plate-like soil ò Prismlike - flat and well defined ò Blocklike - six-sided blocks of aggregate ò Spheroidal - granular and round 3-6

Consistence ò Loose - noncoherent ò Very friable - crush under very gentle pressure ò Friable - crush under gentle pressure ò Firm - crushed with moderate pressure ò Very firm - requires strong pressure ò Extremely firm - resists crushing 3-7

Group Activity

Acidity ò Critical to agricultural activities ò Calcium deficiency contributes ò Measured by pH level ò 7 is neutral ò Most crops prosper with 6.5 to 7 pH 3-9

Soil Depth 3-10

Slope 3-11

Erosion 3-12

Horizons ò Layers determine the characteristics ò Four major horizons ò O horizons ò A horizons ò B horizons ò C horizons 3-13

Understanding Soil Surveys ò NRCS ò System of eight capability classes ò Suitability of soil for cultivation ò Classes based on limitations ò NRCS system includes several subclasses ò NRCS publishes surveys at the county level 3-14

Soil Classes ò Class I - most desirable ò Class II - have some limitations ò Class III - permanent limitations ò Class IV - marginally suited to cultivation ò Class V - fewer erosion hazards ò Class VI - similar restrictions to class IV ò Class VII - similar to limitations of Class VI ò Class VIII - cannot be used 3-15

Factors limiting Soil Productivity 3-16

Factors limiting Soil Productivity (cont..) 3-17

Factors limiting Soil Productivity (cont.) 3-18

Soil Surveys Contents ò Soil Map ò Description of formation ò Description of soils ò Use and management ò Classification of the soils ò Extensive Glossary 3-19

Soil Surveys ò Assign compound names ò First name indicates soil series ò Second name indicates texture ò Characteristics common to subject area ò Permits identification of soils ò Quality and detail of information varies 3-20

Agricultural Production Capabilities ò Production depends on structure ò Dominant textures ò Topsoil depth ò Rooting depth ò Soil fertility ò Slope characteristics 3-21

Soil Capability Classes ò Iowa State University Corn Suitability Ratings CSR 3-22

Soil Analysis  Should draw on various sources  Indicate the history of the property  Include local county extension agent information  May include USDA information  Information from state level agricultural offices  Begin with a set of maps 3-23

Topography Examination  Irrigation  Methods of assigning water rights  Impact of water rights on property value  Drainage - surface or subsurface  Slopes  Erosion potential 3-24

Group Discussion 3-25

Module 3 - Review  Understand the composition of the ideal soil and how it supports agricultural production ò Mineral material ò organic matter ò water ò air ò 45,25,25,5 3-26

Module 3 - Review  Identify the macro and micro nutrients available in soils òNitrogen, Phosphorus, Potassium, Calcium, Magnesium, and Sulfur òIron, Manganese, Copper, Zinc, Boron, Molybdenum, Chlorine, Cobalt 3-27

Module 3 - Review  Understand the concepts of soil texture, structure, and consistence 3-28 òCoarse to Fine òPlaty, Prismlike, Blocklike, Spherical òLoose to Very Fine

Module 3 - Review  Identify the horizons occurring in soil profiles ò O, A, B, and C 3-29

Module 3 - Review  Understand the Natural Resource Conservation Service (NCRS) capability classification system ò Eight Productive capacity Classes 3-30

Module 3 - Review  Access resources to facilitate analysis of the soils of a agricultural property òNCRS soil surveys òLocal Sources 3-31

Self-Assessment Questions  The four major components of soil are  Soil deficiencies develop because of  The three main concepts describing soil character are  The NCRS capability classification system includes all of the following except for  Limitations on soils in the NCRS system refer to  The corn suitability rating (CSR) developed for Iowa soils 3-32