What Makes Soil GoodWhat Makes Soil Good

Analysis of soils assists an agricultural

land brokerage professional estimate

the economic potential of the land

3-1

ObjectivesObjectives

Identify macro and micro nutrients in soil

Soil texture, structure, and consistence

Identify horizons in soil profiles

NCRS capability classification system

Resources to analyze agricultural property

3-2

Important Concepts for Soils Analysis

Important Concepts for Soils Analysis

Four major components of soil

Mineral components develop from parent material

Organic matter

Ingredients that make soil solution

Biological Activity

Plants draw six macronutrients from soil3-3

Important Concepts of Soils Analysis (cont.)

Important Concepts of Soils Analysis (cont.)

Trace elements or micronutrients

N-P-K designation for fertilizer

Soil deficiencies develop from shortages

Characteristics of soils

Texture depends on individual particles

Structure groups soil textures3-4

Establishing Soil TextureEstablishing Soil Texture

Coarse soils - loose and very friable Moderately coarse soils - hold together when

moist Medium soils - feel velvety Moderately fine soils - form clods Fine soils - form hard clods

3-5

Soil StructuresSoil Structures

Four distinct structures

Platy soils - flat plate-like soil

Prismlike - flat and well defined

Blocklike - six-sided blocks of aggregate

Spheroidal - granular and round

3-6

ConsistenceConsistence

Loose - noncoherent

Very friable - crush under very gentle pressure

Friable - crush under gentle pressure

Firm - crushed with moderate pressure

Very firm - requires strong pressure

Extremely firm - resists crushing3-7

Group Activity 3-1Group Activity 3-1

3-8

AcidityAcidity

Critical to agricultural activities

Calcium deficiency contributes

Measured by pH level

7 is neutral

Most crops prosper with 6.5 to 7 pH

3-9

Soil DepthSoil Depth

3-10

SlopeSlope

3-11

ErosionErosion

3-12

HorizonsHorizons

Layers determine the characteristics Four major horizons O horizons A horizons B horizons C horizons

3-13

Understanding Soil SurveysUnderstanding Soil Surveys

NRCS System of eight capability classes Suitability of soil for cultivation Classes based on limitations NRCS system includes several subclasses NRCS publishes surveys at the county level

3-14

Soil ClassesSoil Classes

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

3-15

Factors limiting Soil Productivity

Factors limiting Soil Productivity

3-16

Factors limiting Soil Productivity (cont..)

Factors limiting Soil Productivity (cont..)

3-17

Factors limiting Soil Productivity (cont.)

Factors limiting Soil Productivity (cont.)

3-18

Soil Surveys ContentsSoil Surveys Contents

Soil Map Description of formation Description of soils Use and management Classification of the soils Extensive Glossary

3-19

Soil SurveysSoil Surveys

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

3-20

Agricultural Production Capabilities

Agricultural Production Capabilities

Production depends on structure Dominant textures Topsoil depth Rooting depth Soil fertility Slope characteristics

3-21

Soil Capability ClassesSoil Capability Classes

Iowa State University Corn Suitability Ratings CSR

3-22

Soil AnalysisSoil 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 ExaminationTopography Examination

Irrigation Methods of assigning water rights Impact of water rights on property value Drainage - surface or subsurface Slopes Erosion potential

3-24

Group DiscussionGroup Discussion

3-25

Module 3 - ReviewModule 3 - Review

Understand the composition of the ideal soil and how it supports agricultural production

Mineral material organic matter water air 45,25,25,5

3-26

Module 3 - ReviewModule 3 - Review

Identify the macro and micro nutrients available in soils

Nitrogen, Phosphorus, Potassium, Calcium, Magnesium, and Sulfur

Iron, Manganese, Copper, Zinc, Boron, Molybdenum, Chlorine, Cobalt

3-27

Module 3 - ReviewModule 3 - Review

Understand the concepts of soil texture, structure, and consistence

3-28

Coarse to FinePlaty, Prismlike, Blocklike, SphericalLoose to Very Fine

Module 3 - ReviewModule 3 - Review

Identify the horizons occurring in soil profiles

O, A, B, and C

3-29

Module 3 - ReviewModule 3 - Review

Understand the Natural Resource Conservation Service (NCRS) capability classification system

Eight Productive capacity Classes

3-30

Module 3 - ReviewModule 3 - Review

Access resources to facilitate analysis of the soils of a agricultural property

NCRS soil surveysLocal Sources

3-31

Self-Assessment QuestionsSelf-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