Soil Quality - USDA

1 Soil QualityTest Kit GuideUnited StatesDepartment ofAgricultureAgriculturalResearch ServiceNatural ResourcesConservation ServiceSoil Quality InstituteJuly 2001 Trade names are used solely to provide specific information. Mention of a trade name does not consti-tute a guarantee of the product by the Department of Agriculture nor does it imply endorsementby the Department or the Natural Resources Conservation Service over comparable products that arenot Department of Agriculture ( usda ) prohibits discrimination in all its programs and activities onthe basis of race, color, national origin, gender, religion, age, disability, political beliefs, sexual orienta-tion, or marital or family status.

2 (Not all prohibited bases apply to all programs.) Persons with disabili-ties who require alternative means for communication of program information (Braille, large print,audiotape, etc.) should contact usda s TARGET Center at (202) 720-2600 (voice and TDD).To file a complaint of discrimination, write usda , Director, Office of Civil Rights, Room 326-W, WhittenBuilding, 14th and Independence Avenue, SW, Washington, 20250-9410 or call (202) 720-5964(voice and TDD). usda is an equal opportunity provider and of ContentsPreface ..Section I - Test Procedures: 1. Measuring Soil Quality - discusses sampling and sitecharacterization .. Respiration Test - indicates the soil's Test - measures the soil's abilityto take in water through the soil surface.

3 Density Test - measures the soil's compactionor pore Conductivity (EC) Test - measures the saltconcentration in the Test - measures the soil's acidity or Nitrate Test - measures the soil'snitrate levels .. Stability Test - measures the amount ofwater stable Test - estimates the stability of soilfragments in water .. Test - measures the number of earthwormsin the soil .. 11. Soil Physical Observations and Estimations - shows howto observe soil structure and root patterns and how to estimate topsoildepth, penetration resistance, and soil texture in the soil 12. Water Quality tests estimates salinity andnitrate/nitrite levels in : A.

4 B. Soil Respiration (alternative method).. C. EC and pH Meter Maintenance and D. Building a Soil Quality Test Kit .. E. Site Description data F. Soil Quality data II - Background & interpretive Guide for Individual tests : Introduction .. 1. Soil Respiration .. 2. Infiltration .. 3. Bulk Density .. 4. Electrical Conductivity (EC) .. 5. Soil pH .. 6. Soil Nitrate .. 7. Aggregate Stability .. 8. Soil Slaking .. 9. 10. Soil Physical Observations and Estimations .. 11. Water Quality ..Salinity of waterNitrate/nitrite levels in wateriiPage30313335414351525557596367697 2737579 PREFACESoil Quality is simply defined as the capacity of a specific kind of soil to function.

5 It is gener-ally assessed by measuring a minimum data set of soil properties to evaluate the soil s ability toperform basic functions ( , maintaining productivity, regulating and partitioning of water andsolute flow, filtering and buffering against pollutants, and storing and cycling nutrients). This guidedescribes a kit of selected field procedures to evaluate or indicate the level of one or more measuring soil Quality , it is important to evaluate the physical, chemical, and biologicalproperties of the soil. Physical properties addressed by the kit include bulk density, water content,infiltration rate, aggregate stability, slaking, and morphological estimations.

6 Biological propertiesmeasured include soil respiration and earthworms. Soil chemical properties measured include pH,electrical conductivity (EC), and soil nitrate levels. The chemical tests are also useful to evaluatewater Quality of well-water, tile drainage waters, and other water bodies related to farm I of this guide provides a list of supplies and instructions for conducting a number of on-farm tests to assess soil Quality . Section II provides background and interpretive information foreach test described in Section I. These tests , or indicators, are designed as a screening tool to pro-vide immediate results for comparing management systems, monitoring changes in soil Quality overtime, and for diagnosing possible soil health problems due to land use and management.

7 These tests can be easily conducted on the farm by NRCS field personnel or by landownersthemselves to assess the Quality of their soil. Use of the kit allows NRCS staff to be an active par-ticipant with the landowner in the assessment of soil health. The assessment will provide the oppor-tunity to discuss management options when the need kit was developed by John Doran and associates, Agricultural Research Service, Lincoln,NE. The Soil Quality Institute has continued the development, enhancement and testing of the kit(with NRCS field staff) by adding tests , modifying the manual, and writing an interpretations NRCS Soil Quality Team in Akron, CO (Manuel Rosales, Josh Saunders, and Mike Sucik) wereinstrumental in the field testing of the test kit and this guide.

8 The Soil Quality Test Kit Guide is adynamic document. The Institute welcomes suggestions for additional tests and interpretive infor-mation to incorporate in future versions of the Institute gratefully acknowledges the contributions of the following individuals: JohnDoran, usda -ARS, Lincoln, NE, for the development of the original soil Quality test kit from whichthis guide is based. Bob Grossman, usda -NRCS, NSSC, Lincoln, NE, for the development of thesoil structure index and penetration resistance tests . Jeff Herrick, usda -ARS, Las Cruces, NM, forthe development of the soil slake test procedure and aggregate stability test design. Dennis Linden, usda -ARS, St.

9 Paul, MN, for the development of the earthworm procedure. Bob Hanafin, AuburnUniversity, for the development of the design and layout of this guide. Cathy Seybold and LeeNorfleet, usda -NRCS, Soil Quality Institute, for the development of this guide and testing of mission of the Soil Quality Institute is to cooperate with partners in the development, acqui-sition, and dissemination of soil Quality information and technology to help people conserve andsustain our natural resources and the more information about the Soil Quality Institute and its products and services, visit ourwebsite at Quality Institute Staffiii11. Measuring Soil QualitySoil Quality integrates the physical, chemical, and biological components of soil and their interac-tions.

10 Therefore, to capture the holistic nature of soil Quality or health, all of the parameters in thekit should be measured. However, not all parameters have equal relevance to all soils and situa-tions. For example, the EC test for salinity may not be useful in the eastern part of the wheresalinity is not a problem. A minimum data set of soil properties, or indicators, from each of thethree soil components are selected based on their ability to indicate the capacity of the soil tofunction for a specific land use, climate, and soil type. Indicators in the soil Quality kit are selectedprimarily for agricultural soil Quality assessments. The kit should be used as a screening tool togive the general trend or direction of soil Quality --whether current management systems are main-taining, enhancing, or degrading the soil.