DOCSLIB.ORG

Revisiting the Standard Soil Test: the Potential of Macro- and Microbiological Measures to Improve Agricultural Health and Productivity

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Revisiting the Standard Soil Test: the Potential of Macro- and Microbiological Measures to Improve Agricultural Health and Productivity University of South Carolina Scholar Commons Theses and Dissertations Fall 2019 Revisiting the Standard Soil Test: The Potential of Macro- and Microbiological Measures to Improve Agricultural Health and Productivity Gabriel Jacob Kenne Follow this and additional works at: https://scholarcommons.sc.edu/etd Part of the Environmental Health Commons Recommended Citation Kenne, G. J.(2019). Revisiting the Standard Soil Test: The Potential of Macro- and Microbiological Measures to Improve Agricultural Health and Productivity. (Doctoral dissertation). Retrieved from https://scholarcommons.sc.edu/etd/5547 This Open Access Dissertation is brought to you by Scholar Commons. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. REVISITING THE STANDARD SOIL TEST: THE POTENTIAL OF MACRO- AND MICROBIOLOGICAL MEASURES TO IMPROVE AGRICULTURAL HEALTH AND PRODUCTIVITY by Gabriel Jacob Kenne Bachelor of Science University of Nebraska at Omaha, 2008 Master of Public Health Kansas State University, 2013 Submitted in Partial Fulfillment of the Requirements For the Degree of Doctor of Philosophy in Environmental Health Sciences The Norman J. Arnold School of Public Health University of South Carolina 2019 Accepted by: R. Sean Norman, Major Professor Anindya Chanda, Committee Member Robin “Buz” Kloot, Committee Member Geoff Zehnder, Committee Member Cheryl L. Addy, Vice Provost and Dean of the Graduate School © Copyright Gabriel Jacob Kenne, 2019 All Rights Reserved ii ABSTRACT The agricultural ecosystem has become the largest non-ice-covered terrestrial ecosystem on the planet and has significant direct and indirect impacts on the global health of both the environment and humanity. Recent shifts in modern agriculture are beginning to focus on the health of soil versus a focus traditionally on crop health and yield at any cost. By managing farmland regeneratively, systems are able to reverse many of the problems created by conventional land management such as erosion and unwanted nutrient runoff, and simultaneously create opportunities to move C from the atmosphere back into the soil. While the ways in which farmland is managed are beginning a necessary shift, the ways in which soil fertility is measured in the process of monitoring and understanding these management changes also need to be adjusted. This dissertation aims to begin that adjustment by evaluating data commonly overlooked in traditional soil tests and the effectiveness of both standard and new soil health tests at prescribing fertilizer recommendations in regeneratively managed soils, and exploring the potential of high-throughput metagenome analyses as a means to measure soil health. Organic Matter data collected from standard soils tests shows that statewide, SC has the potential to sequester 500,647 – 1,558,092 tons of atmospheric carbon per year with the adoption of no-till and cover cropping practices on its 1,967,288 acres of cropland. The yield-predictive capability of these same soil tests, as well as with Haney Soil Health tests, confirmed an expected yield-response to N fertilizer based on field trials, but both showed almost no soil test value that consistently correlated with actual iii crop yields through two full corn-wheat-soybean crop rotations in the coastal plains of SC, bringing into question the effectiveness of current soil testing methods. Finally, the examination of 6” soil metagenomes throughout a single winter wheat crop showed that traditional versus regenerative land management practices had some significant impacts on the soil microbiomes’ potential ability to cycle and recycle nitrogen. These data show the need for continued reexamination of both current agricultural systems as well as the tools by which these systems are measured, and their management decisions made. iv TABLE OF CONTENTS Abstract .............................................................................................................................. iii List of Tables .................................................................................................................... vii List of Figures .................................................................................................................. viii List of Abbreviations ...........................................................................................................x Chapter 1: Introduction ........................................................................................................1 Chapter 2: The Carbon Sequestration Potential of Regenerative Farming Practices in South Carolina, USA ...........................................................................................................4 2.1. Introduction .......................................................................................................4 2.2. Sample Collection & Analysis ..........................................................................7 2.3. Results .............................................................................................................10 2.4. Discussion .......................................................................................................11 2.5. Limitations ......................................................................................................16 2.6. Conclusion ......................................................................................................18 2.7. Figures and Tables ..........................................................................................20 Chapter 3: Comparing Predictive Capability of the Mehlich 1 and Haney Soil Health Tests on Regeneratively Managed Soil Fertility and Crop Productivity ...........................26 3.1. Introduction .....................................................................................................26 3.2. Methods...........................................................................................................35 3.3. Results .............................................................................................................43 3.4. Discussion .......................................................................................................47 3.5. Conclusions .....................................................................................................53 v 3.6. Figures and Tables ..........................................................................................55 Chapter 4: The Impact of Regenerative and Conventional Land Management Practices on the Functional Potential and Microbial Community Harboring Nitrogen-Cycling Genes Within the Soil ...................................................................................................................64 4.1. Introduction .....................................................................................................64 4.2. Methods...........................................................................................................75 4.3. Results .............................................................................................................82 4.4. Discussion .......................................................................................................89 4.5. Conclusions ...................................................................................................100 4.6. Figures and Tables ........................................................................................102 Chapter 5: Conclusions and Future Work ........................................................................134 References ........................................................................................................................137 Appendix A: Activation of Aflatoxin Biosynthesis Alleviates Total ROS in Aspergillus parasiticus ........................................................................................................................163 A.1. Introduction ..................................................................................................163 A.2. Results ..........................................................................................................165 A.3. Discussion ....................................................................................................170 A.4. Materials and Methods .................................................................................174 A.5. Figures and Tables .......................................................................................179 vi LIST OF TABLES Table 2.1 Description of individual projects and sampling methods used ........................24 Table 2.2 Mean increase in soil OM and C by sampling group ........................................24 Table 2.3 Mean annual rates of change in soil OM by soil texture ...................................25 Table 2.4 Compiled soil test organic matter values from single-event samples throughout SC by soil texture ...............................................................................................................25 Table 2.5 %OM at depth in a random sampling from the 3-year plots .............................25 Table 3.1 Fertilizer treatment applications (in kg/ha N-P2O5-K2O) by crop year for each treatment group ..................................................................................................................55 Table 3.2 Standard soil and Haney soil health test measures ............................................57
Load more

Recommended publications
  • Simple Soil Tests for On-Site Evaluation of Soil Health in Orchards
    sustainability Article Simple Soil Tests for On-Site Evaluation of Soil Health in Orchards Esther O. Thomsen 1, Jennifer R. Reeve 1,*, Catherine M. Culumber 2, Diane G. Alston 3, Robert Newhall 1 and Grant Cardon 1 1 Dept. Plant Soils and Climate, Utah State University, Logan, UT 84322, USA; [email protected] (E.O.T.); [email protected] (R.N.); [email protected] (G.C.) 2 UC Cooperative Extension, Fresno, CA 93710, USA; [email protected] 3 Dept. Biology, Utah State University, Logan, UT 84322, USA; [email protected] * Correspondence: [email protected] Received: 20 September 2019; Accepted: 26 October 2019; Published: 29 October 2019 Abstract: Standard commercial soil tests typically quantify nitrogen, phosphorus, potassium, pH, and salinity. These factors alone are not sufficient to predict the long-term effects of management on soil health. The goal of this study was to assess the effectiveness and use of simple physical, biological, and chemical soil health indicator tests that can be completed on-site. Analyses were conducted on soil samples collected from three experimental peach orchards located on the Utah State Horticultural Research Farm in Kaysville, Utah. All simple tests were correlated to comparable lab analyses using Pearson’s correlation. The highest positive correlations were found between Solvita®respiration, and microbial biomass (R = 0.88), followed by our modified slake test and microbial biomass (R = 0.83). Both Berlese funnel and pit count methods of estimating soil macro-organism diversity were fairly predictive of soil health. Overall, simple commercially available chemical tests were weak indicators of soil nutrient concentrations compared to laboratory tests.
    [Show full text]
  • Soil Testing Can Help Nutrient Deficiencies Or Imbalances
    Do You Have Problems With: • Nutrient deficiencies in crops • Poor plant growth and response from applied fertilizers • Hard to manage weeds • Low crop yields • Poor quality forages • Irregular plant growth in your fields • Managing manure or compost applications Soil tests help to identify production problems related to Soil Testing Can Help nutrient deficiencies or imbalances. Above: Nitrogen defi- ciency in corn (photo: Ryan Stoffregen, Illinois). Below: Phosphorus deficiency in corn. Source: www.ipni.net Benefits of Soil Testing: • Determines nutrient levels in the soil • Determines pH levels (lime needs) • Provides a decision making tool to determine what nutrients to apply and how much • Potential for higher yielding crops • Potential for higher quality crops • More efficient fertilizer use Costs: Generally soil tests cost $7 to $10.00 per sample. The costs of soil tests vary depending on: 1. Your state (some states offer free soil testing) 2. The lab that is used. 3. The items being tested for (the cost increases as more nutrients are being analyzed). NOTE: Some state agencies and land grant universities provide free soil testing for the basic soil test items (pH, available phosphorus, potassium, calcium, and magnesium, and organic matter). Additional costs may be charged for testing for micronutrients. In other states, all soil testing is done by private labs and generally charge $7-$10 for the basic test. One soil test should be taken for each field, or for each 20 acres within a field. See example on page 3. Soil Testing How Often Should I Soil Test? Generally, you should soil test every 3-5 years or more often if manure is applied or you are trying to make large nutrient or pH changes in the soil.
    [Show full text]
  • A Sustainable Approach for Improving Soil Properties and Reducing N2O Emissions Is Possible Through Initial and Repeated Biochar Application
    agronomy Article A Sustainable Approach for Improving Soil Properties and Reducing N2O Emissions Is Possible through Initial and Repeated Biochar Application Ján Horák 1,* , Tatijana Kotuš 1, Lucia Toková 1, Elena Aydın 1 , Dušan Igaz 1 and Vladimír Šimanský 2 1 Department of Biometeorology and Hydrology, Faculty of Horticulture and Landscape Engineering, Slovak University of Agriculture, 949 76 Nitra, Slovakia; [email protected] (T.K.); [email protected] (L.T.); [email protected] (E.A.); [email protected] (D.I.) 2 Department of Soil Science, Faculty of Agrobiology and Food Resources, Slovak University of Agriculture, 949 76 Nitra, Slovakia; [email protected] * Correspondence: [email protected] Abstract: Recent findings of changing climate, water scarcity, soil degradation, and greenhouse gas emissions have brought major challenges to sustainable agriculture worldwide. Biochar application to soil proves to be a suitable solution to these problems. Although the literature presents the pros and cons of biochar application, very little information is available on the impact of repeated application. In this study, we evaluate and discuss the effects of initial and reapplied biochar (both in rates of 0, 10, and 20 t ha−1) combined with N fertilization (at doses of 0, 40, and 80 kg ha−1) on soil properties and N O emission from Haplic Luvisol in the temperate climate zone (Slovakia). Results showed that 2 biochar generally improved the soil properties such as soil pH(KCl) (p ≤ 0.05; from acidic towards Citation: Horák, J.; Kotuš, T.; Toková, moderately acidic), soil organic carbon (p ≤ 0.05; an increase from 4% to over 100%), soil water L.; Aydın, E.; Igaz, D.; Šimanský, V.
    [Show full text]
  • Soil Test Handbook for Georgia
    SOIL TEST HANDBOOK FOR GEORGIA Georgia Cooperative Extension College of Agricultural & Environmental Sciences The University of Georgia Athens, Georgia 30602-9105 EDITORS: David E. Kissel Director, Agricultural and Environmental Services Laboratories & Leticia Sonon Program Coordinator, Soil, Plant, & Water Laboratory The University of Georgia and Ft. Valley State University, the U.S. Department of Agriculture and counties of the state cooperating. The Cooperative Extension, the University of Georgia College of Agricultural and Environmental Sciences offers educational programs, assistance and materials to all people without regard to race, color, national origin, age, sex or disability. An Equal Opportunity Employer/Affirmative Action Organization Committed to a Diverse Work Force Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, The University of Georgia College of Agricultural and Environmental Sciences and the U.S. Department of Agriculture cooperating. Dr. Scott Angle, Dean and Director Special Bulletin 62 September 2008 i TABLE OF CONTENTS INTRODUCTION .......................................................................................................................................................2 SOIL TESTING...........................................................................................................................................................4 SOIL SAMPLING .......................................................................................................................................................4
    [Show full text]
  • Addressing Pasture Compaction
    Addressing Pasture Compaction Weighing the Pros and Cons of Two Options UVM Project team: Dr. Josef Gorres, Dr. Rachel Gilker, Jennifer Colby, Bridgett Jamison Hilshey Partners: Mark Krawczyk (Keyline Vermont) and farmers Brent & Regina Beidler, Guy & Beth Choiniere, John & Rocio Clark, Lyle & Kitty Edwards, and Julie Wolcott & Stephen McCausland Writing: Josef Gorres, Rachel Gilker and Jennifer Colby • Design and Layout: Jennifer Colby • Photos: Jennifer Colby and Rachel Gilker Additional editing by Cheryl Herrick and Bridgett Jamison Hilshey Th is is dedicated to our farmer partners; may our work help you farm more productively, profi tably, and ecologically. VT Natural Resources Conservation Service UVM Center for Sustainable Agriculture http://www.vt.nrcs.usda.gov http://www.uvm.edu/sustainableagriculture UVM Plant & Soil Science Department http://pss.uvm.edu Financial support for this project and publication was provided through a VT Natural Resources Conservation Service (NRCS) Conservation Innovation Grant (CIG). We thank VT-NRCS for their eff orts to build a 2 strong natural resource foundation for Vermont’s farming systems. Introduction A few years ago, some grass-based dairy farmers came to us with the question, “You know, what we really need is a way to fi x the compaction in pastures.” We started digging for answers. Th is simple request has led us on a lively journey. We began by adapting methods to alleviate compac- tion in other climates and cropping systems. We worked with fi ve Vermont dairy farmers to apply these practices to their pastures, where other farmers could come and observe them in action. We assessed the pros and cons of these approaches and we are sharing those results and observations here.
    [Show full text]
  • Bacteria in Agrobiology: Stress Management
    Bacteria in Agrobiology: Stress Management Bearbeitet von Dinesh K. Maheshwari 1. Auflage 2012. Buch. XII, 333 S. Hardcover ISBN 978 3 642 23464 4 Format (B x L): 15,5 x 23,5 cm Gewicht: 684 g Weitere Fachgebiete > Chemie, Biowissenschaften, Agrarwissenschaften > Entwicklungsbiologie > Bakteriologie (nichtmedizinisch) Zu Inhaltsverzeichnis schnell und portofrei erhältlich bei Die Online-Fachbuchhandlung beck-shop.de ist spezialisiert auf Fachbücher, insbesondere Recht, Steuern und Wirtschaft. Im Sortiment finden Sie alle Medien (Bücher, Zeitschriften, CDs, eBooks, etc.) aller Verlage. Ergänzt wird das Programm durch Services wie Neuerscheinungsdienst oder Zusammenstellungen von Büchern zu Sonderpreisen. Der Shop führt mehr als 8 Millionen Produkte. Chapter 2 The Management of Soil Quality and Plant Productivity in Stressed Environment with Rhizobacteria Dilfuza Egamberdieva 2.1 Introduction The urgency of feeding the world’s growing population while combating soil pollution, salinization, and desertification has given plant and soil productivity research vital importance. Under such circumstances, it requires suitable biotech- nology not only to improve crop productivity but also to improve soil health through interactions of plant roots and soil microorganisms (Lugtenberg et al. 2002). Interest in bacterial fertilizers has increased, as it would substantially reduce the use of chemical fertilizers and pesticides which often contribute to the pollution of soil–water ecosystems. Presently, about 20 biocontrol products based on Pseu- domonas, Bacillus, Streptomyces, and Agrobacterium strains have been commercialized, but there still is a need to improve the efficacy of these biocontrol products (Copping 2004; Chebotar et al. 2000; Lugtenberg and Kamilova 2004). Soil salinity disturbs the plant–microbe interaction, which is a critical ecological factor to help further plant growth in degraded ecosystems (Paul and Nair 2008).
    [Show full text]
  • Soil, Plant and Water Reference Methods for the Western Region1
    SOIL, PLANT AND WATER REFERENCE METHODS FOR THE WESTERN REGION 1 2005 3rd Edition Dr. Ray Gavlak Dr. Donald Horneck Dr. Robert O. Miller 1 From: Plant, Soil and Water Reference Methods for the Western Region. 1994. R. G. Gavlak, D. A. Horneck, and R. O. Miller. WREP 125. PREFACE This manual has been developed as a guide of standard analytical methods for agricultural laboratories for use in the Western Region, byt the Western Coordinating Committee on Nutrient Management. This publication an update of Plant, Soil and Water Reference Methods for the Western Region , 1994, (WREP 125) written by Dr. Ray Gavlak formerly of the University of Alaska, Dr. Donald Horneck of Oregon State University, and Dr. Robert O. Miller of Colorado State University. These represent accepted methods for the analysis of soil and plant samples and were selected for the express purpose of identifying common methods on which a group of agricultural laboratories analytical results can be statistically evaluated. We would like to thank all those individuals who have contributed to this manual. The specific soil, plant and water analytical methods listed represent those analytical procedures that are recommended for use in the current North American Proficiency Testing Program organized by the Soil Science Society of America. We encourage all suggestions and comments from participating laboratories for improving this manual for future publication. The authors would like to thank Dr. Byron Vaughan of MDS Harris Laboratory Services, Dr. Kelly Belden of the University of Wyoming for reviewing this publication. WREP-125, 3 rd Edition TABLE OF CONTENTS Page Quality Assurance in the Agricultural Laboratory .....................................
    [Show full text]
  • The Effect of Different Doses of N Fertilization on the Parameters of Soil Organic Matter and Soil Sorption Complex
    Journal of Ecological Engineering Volume 18, Issue 3, May 2017, pages 104–111 DOI: 10.12911/22998993/69366 Research Article THE EFFECT OF DIFFERENT DOSES OF N FERTILIZATION ON THE PARAMETERS OF SOIL ORGANIC MATTER AND SOIL SORPTION COMPLEX Vladimír Šimanský1, Peter Kováčik2, Jerzy Jonczak3 1 Department of Soil Science, Faculty of Agrobiology and Food Resources, Slovak University of Agriculture, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia, e-mail: [email protected] 2 Department of Agrochemistry and Plant Nutrition, Faculty of Agrobiology and Food Resources, Slovak University of Agriculture, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia 3 Department of Soil Environment Sciences, Warsaw University of Life Sciences – SGGW, Poland Received: 2017.06.03 ABSTRACT Accepted: 2017.04.05 Mineral N fertilizer application may have an effect on soil organic matter and other Published: 2017.05.02 soil parameters. Therefore, we studied the effects of different doses of N fertilization on soil organic matter and chemical properties of Haplic Luvisol in the locality of Dolná Malanta (Slovakia) during 2014–2016. Soil samples were collected from the plots exposed to the following treatments: 1. N0 – no N fertilization as control dur- ing 2014–2016, 2. N40 – N fertilizer at the rate of 40 kg N ha–1 in 2014 and 2016, 3. N80 – N fertilizer at the rate of 80 kg N ha–1 in 2014 and 2016, 4. N160 – N fertilizer at the rate of 160 kg N ha–1 in 2015, and 5. N240 – N fertilizer at the rate of 240 kg N ha–1 in 2015.
    [Show full text]
  • MREI 12-01 – Geotechnical Guidelines for Sample Handling, Testing and Data Reporting
    MREI 12-01 – Geotechnical Guidelines for Sample Handling, Testing and Data Reporting VTrans Materials & Research Engineering Instructions MREI 12-01 Distribution: Structures, Director PDD, Assistant Director PDD, PDD Section Managers, Chief of Contract Admin., Director Ops., Assistant Director Ops., Consultants. Approved: Date: 12-27-2012 William E. Ahearn, Materials and Research Engineer Subject: Geotechnical Guidelines to Standardize VTrans’ Sample Handling, Testing and Data Reporting Procedures Administrative Information: Effective Date: This Materials & Research Engineering Instruction (MREI) shall be considered effective from the date of approval. Superseded MREI: None Disposition of MREI Content: The content of this MREI will be incorporated into a future VTrans Soils & Foundations Engineering Manual. 1. PURPOSE: The purpose of this MREI is to standardize Geotechnical sample handling, testing and data reporting procedures performed at the Vermont Agency of Transportation, Materials & Research Laboratory. 2. TECHNICAL INFORMATION: In general, guidance outlined in Sections 9.0 and 10.0 of AASHTO Manual of Subsurface Investigations, 1988 and Section 4.12.2 of FHWA’s Geotechnical Engineering Circular No. 5, GEC No. 5 shall be followed. Any specific guidance presented in this MREI that differs from these references shall take precedence. Page 1 of 20 MREI 12-01 – Geotechnical Guidelines for Sample Handling, Testing and Data Reporting 3. OVERVIEW: Handling of geotechnical samples from field to laboratory can be critical to the integrity of the material to be tested. Proper handling methods are addressed to assure the material to be tested yields meaningful and representative data. The means of identifying and tracking materials to be tested are identified allowing for a traceable record for each sample.
    [Show full text]
  • Methods of Analysis Soil Sampling
    Soil Sampling and Methods of Analysis Second Edition ß 2006 by Taylor & Francis Group, LLC. In physical science the first essential step in the direction of learning any subject is to find principles of numerical reckoning and practicable methods for measuring some quality connected with it. I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely in your thoughts advanced to the state of science, whatever the matter may be. Lord Kelvin, Popular Lectures and Addresses (1891–1894), vol. 1, Electrical Units of Measurement Felix qui potuit rerum cognoscere causas. Happy the man who has been able to learn the causes of things. Virgil: Georgics (II, 490) ß 2006 by Taylor & Francis Group, LLC. Soil Sampling and Methods of Analysis Second Edition Edited by M.R. Carter E.G. Gregorich Canadian Society of Soil Science ß 2006 by Taylor & Francis Group, LLC. CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2008 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works Printed in the United States of America on acid-free paper 10 9 8 7 6 5 4 3 2 1 International Standard Book Number-13: 978-0-8493-3586-0 (Hardcover) This book contains information obtained from authentic and highly regarded sources.
    [Show full text]
  • Recommended Chemical Soil Test Procedures for the North Central Region
    North Central Regional Research Publication No. 221 (Revised) Recommended Chemical Soil Test Procedures for the North Central Region Agricultural Experiment Stations of Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, Pennsylvania, South Dakota and Wisconsin, and the U.S. Department of Agriculture cooperating. Missouri Agricultural Experiment Station SB 1001 Revised January 1998 (PDF corrected February 2011) Foreword Over the past 30 years, the NCR-13 Soil Testing Agricultural Experiment Stations over the past five and Plant Analysis Committee members have worked decades have been used to calibrate these recom- hard at standardizing the procedures of Soil Testing mended procedures. Laboratories with which they are associated. There NCR-13 wants it clearly understood that the have been numerous sample exchanges and experi- publication of these tests and procedures in no way ments to determine the influence of testing method, implies that the ultimate has been reached. Research sample size, soil extractant ratios, shaking time and and innovation on methods of soil testing should con- speed, container size and shape, and other laboratory tinue. The committee strongly encourages increased procedures on test results. As a result of these activi- research efforts to devise better, faster, less expensive ties, the committee arrived at the recommended pro- and more accurate soil tests. With the high cost of fer- cedures for soil tests. tilizer, and with the many soil related environmental Experiments have shown that minor deviations concerns, it is more important than ever that fertilizer in procedures may cause significant differences in test be applied only where needed and in the amount of results.
    [Show full text]
  • DIY Soil Tests
    222 N Havana Spokane WA 99202 (509) 477-2181 http://extension.wsu.edu/Spokane e-mail: [email protected] C221 EASY DO-IT-YOURSELF (DIY) SOIL TESTS Soil quality is simply defined as “the capacity of a specific kind of soil to function.” When measuring soil quality, it is important to evaluate the physical, chemical, and biological properties of the soil. By focusing more attention on soil health and the positive impact healthy soils can have on productivity and conservation, we can feed ourselves more profitably and sustainably – now and for generations to come. Washington State University publication, A Home Gardener’s Guide to Soils and Fertilizers, has a wealth of information on the topic of soil and soil health. USDA Natural Resources Conservation Service (Baseline/Physical/Chemical): Your exact location is most likely mapped on the existing the USDA Web Soil Survey. You can find your soil series, soil type (loam, sand, clay), pH, other physical and chemical attributes, plus reference data and management advice. OBSERVATION Tilth (condition of the soil) When the soil is neither too wet nor too dry, dig a hole 6 to 10 inches deep. Separate an intact section about the size of a soup can and break it apart with your fingers. Determine whether the soil is cloddy, powdery, or granular. Ideally, your soil should be made up of different sized crumbs that will hold their shape under slight pressure. Crumbs, or aggregates, as soil scientists call them, that break apart only with difficulty mean your soil is too hard. Soil that's easy to work allows water to reach roots efficiently and is less prone to compaction.
    [Show full text]