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Soil Test Handbook for Georgia

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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 TABLE OF CONTENTS INTRODUCTION .......................................................................................................................................................2 SOIL TESTING...........................................................................................................................................................4 SOIL SAMPLING .......................................................................................................................................................4 SAMPLING TOOLS ......................................................................................................................................................5 SIZE OF AREA TO SAMPLE..........................................................................................................................................5 Traditional Methods.............................................................................................................................................5 Precision Agriculture Methods.............................................................................................................................5 AREAS NOT TO SAMPLE ............................................................................................................................................5 NUMBER OF CORES....................................................................................................................................................6 WHEN TO SAMPLE .....................................................................................................................................................6 CONTAMINATION.......................................................................................................................................................7 SPECIFIC SAMPLING PROCEDURES .............................................................................................................................7 Plowed Field Soils................................................................................................................................................7 Pasture and No-Till Fields....................................................................................................................................7 Orchards...............................................................................................................................................................7 Gardens ................................................................................................................................................................8 Lawns and Turf ....................................................................................................................................................8 Subsoil Sampling .................................................................................................................................................8 SOIL TESTING SERVICES AVAILABLE AT THE SOIL, PLANT, AND WATER LABORATORY............9 DETERMINING THE APPROPRIATE SOIL TEST ...........................................................................................11 OTHER ANALYTICAL SERVICES AVAILABLE AT THE AGRICULTURAL AND ENVIRONMENTAL SERVICES LABORATORIES ................................................................................................................................12 PLANT TISSUE ANALYSIS.........................................................................................................................................12 FEED AND FORAGE ANALYSIS .................................................................................................................................12 WATER ANALYSIS ...................................................................................................................................................13 ANIMAL WASTE (POULTRY LITTER, MANURE, AND LAGOON) ................................................................................13 BIOSOLIDS, SLUDGE, AND NON-ANIMAL WASTE.....................................................................................................13 SUPPLIES AVAILABLE FROM THE COOPERATIVE EXTENSION STOREKEEPER..............................14 SUPPLIES AVAILABLE FROM THE SOIL, PLANT, AND WATER LABORATORY .................................14 PROCEDURES FOR SUBMITTING SOIL SAMPLES TO THE UNIVERSITY OF GEORGIA SOIL, PLANT, AND WATER LABORATORY................................................................................................................16 LABORATORY LOCATION AND TURNAROUND TIME.................................................................................................16 PROCEDURE.............................................................................................................................................................16 USE OF SOIL CODE...................................................................................................................................................16 PLANT ANALYSIS.....................................................................................................................................................16 COTTON PETIOLE ANALYSIS....................................................................................................................................17 FEED ANALYSIS.......................................................................................................................................................17 WATER ANALYSIS ...................................................................................................................................................17 ANIMAL WASTE.......................................................................................................................................................18 Poultry Litter......................................................................................................................................................18 Manure and Lagoon ...........................................................................................................................................18 BIOSOLIDS, SLUDGE, AND NON-ANIMAL WASTE .....................................................................................................18 MECHANICAL ANALYSIS .........................................................................................................................................18 SOIL ANALYSIS PROCEDURES USED AT THE UNIVERSITY OF GEORGIA SOIL, PLANT, AND WATER LABORATORY.........................................................................................................................................19 SAMPLE PREPARATION ............................................................................................................................................19 SOIL PH, LIME BUFFER CAPACITY, AND LIME REQUIREMENT .................................................................................19 ii EXTRACTABLE PHOSPHORUS, POTASSIUM, CALCIUM, MAGNESIUM, MANGANESE AND ZINC .................................19 CATION EXCHANGE CAPACITY (CEC) AND PERCENT BASE SATURATION (BS).......................................................19 HOT-WATER EXTRACTABLE BORON .......................................................................................................................20 ORGANIC MATTER CONTENT...................................................................................................................................20 SOLUBLE SALTS.......................................................................................................................................................20 EXTRACTABLE AMMONIUM AND NITRATE ..............................................................................................................20 TOTAL ELEMENTAL ANALYSIS ................................................................................................................................20 ARSENIC, SELENIUM, AND MERCURY ......................................................................................................................20 TOTAL CARBON, NITROGEN, AND SULFUR ..............................................................................................................20 GREENHOUSE OR NURSERY MEDIA TEST.................................................................................................................20 MECHANICAL ANALYSIS .........................................................................................................................................20 SOIL TEST INTERPRETATION & RECOMMENDATIONS............................................................................21 SOIL ACIDITY ..........................................................................................................................................................21 LIME REQUIREMENT (L.R.)......................................................................................................................................22 DETERMINING THE SOIL LIME REQUIREMENT..........................................................................................................23 How to Use the Lime Requirement
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