Soil Testing

Edward Hanlon, B. L. McNeal, Edward A. Hanlon, andBrian L. McNeal
Other Contacts: Paul White andRao Mylavarapu

This document is about interpreting electrical conductivity (EC) measurements in soils and container media to manage soluble salts from fertilizers, irrigation water, and storm events. It explains how excessive salts affect plant growth, provides guidelines for testing and interpreting EC values, and offers practical recommendations for leaching salts and preventing salt accumulation in landscapes, crops, and containerized plants. First printed April 1993.

S. H. Daroub, T. A. Lang, O. A. Diaz, and M. Chen

Davie M. Kadyampakeni, Kelly T. Morgan, Arnold Schumann, Rhuanito Ferrarezi, andRhuanito S. Ferrarezi

Standard procedures for sampling, preparing, and analyzing soil should be followed for meaningful interpretations of the test results and accurate recommendations.

Rao Mylavarapu, Jamin Bergeron, and Nancy Wilkinson

George Hochmuth, Rao Mylavarapu, and Ed Hanlon

Kelly T. Morgan
Other Contacts: Davie M. Kadyampakeni andJamie D. Burrow

Citrus Soil pH Testing Procedures

Shouan Zhang, Aaron J. Palmateer, Ken Pernezny, and R. T. McMillan, Jr.

Rao Mylavarapu, Yuncong Li, Maria L. Silveira, Maria L. Silveira, Cheryl Mackowiak, J. Mabry McCray, andJames M. McCray
Other Contacts: Paul White

Thomas Obreza, Thomas A. Obreza, Mongi Zekri, Edward Hanlon, andEdward A. Hanlon
Other Contacts: Davie M. Kadyampakeni

This publication is part of SL253, Nutrition of Florida Citrus Trees, 3rd Edition. For references, a glossary, and appendices, please refer to the full document at https://ask.ifas.ufl.edu/publication/SS478.

Rao Mylavarapu, Tom Obreza, Kelly Morgan, George Hochmuth, Vimala Nair, and Alan Wright

Soil testing is a multistep process starting with the collection of a sample that adequately represents the area or field to be tested. Due to wide-ranging soil conditions across Florida and the United States, multiple soil test methods exist. During the 1970s, Florida along with several other southeastern US states adopted Mehlich-1 (M1) as the official extractant for acidic soils. The UF/IFAS Plant Nutrient Oversight Committee approved the change from M1 to M3 in 2010. Based on observations of the interpretations, the technical committee revised the M3 interpretation in March 2014. The new interpretations have been correlated with the M1 interpretations, as closely and realistically as possible, so the actual nutrient recommendations are not changed.

George Hochmuth, Rao Mylavarapu, and Ed Hanlon

George Hochmuth, Rao Mylavarapu, and Ed Hanlon

Qiang Zhu, Yuncong Li, Guodong Liu, Monica Ozores-Hampton, andMonica Ozores-Hampton

This article describes a convenient method to estimate soil carbonate concentration using vinegar and other simple instruments for growers, Extension agents, and students interested in crop production and enhancing crop yield.

J. Mabry McCray, James M. McCray, andRonald W. Rice
Other Contacts: Niguss Solomon Hailegnaw

This publication provides a history of the University of Florida Everglades Soil Testing Laboratory (EvSTL), current analytical methods, and information about fertilizer recommendations made by the laboratory. Written by J. Mabry McCray and Ronald W. Rice, and published by the UF/IFAS Agronomy Department, October 2023.

Lilit Vardanyan andVimala D. Nair

Phosphorus (P) is essential for plant growth and productivity. Excessive application of P fertilizers has contributed to environmental degradation through runoff and leaching into waterways. Traditionally, the Mehlich 1-P and Mehlich 3-P soil tests have been used widely to guide fertilizer recommendations in Florida and many other regions. However, these may provide inaccurate estimates of plant-available P, especially in soils with diverse mineralogy or strong P-sorption capacity. This can result in suboptimal fertilization practices. Unlike standard soil tests, which rely on chemical extractants that may mobilize both labile and non-labile forms of P, the iron oxide strip P (FeO-P) method targets the fraction most relevant to plant uptake, offering a more reliable indicator of P availability. FeO-P mimics the absorptive behavior of plant roots to determine actual crop nutrient demand, providing an improved diagnostic tool for both agronomic and environmental applications.

Rao S. Mylavarapu, Nancy Wilkinson, and Yvens Jean

The UF/IFAS Analytical Services Laboratories (ANSERV labs) have been in operation, under slightly different names, for nearly 70 years. Since 2008, the ANSERV Labs have been reorganized to accomplish specific research and cooperative extension service missions through two sections in each area- Analytical Research (ARL) and NELAC Certified Environmental Water Quality Labs (EWQL) for all researchers and students and Extension Soil Testing (ESTL) and Livestock Waste Testing Labs (LWTL) for all citizens and agencies of Florida.  The procedures described in this manual reflect the current methodologies for agricultural testing offered by the UF/IFAS Extension Soil Testing Laboratory (ESTL), the Livestock Waste Testing Laboratory (LWTL), the Analytical Research Laboratory (ARL), and the Environmental Water Quality Laboratory (EWQL). This Circular replaces previous information that is contained in other UF/IFAS publications.

Adesuwa S. Erhunmwunse, Hui-Ling Liao, andKaile Zhang

Soil microbes play important roles in soil health processes, such as nutrient cycling, organic matter decomposition, and aggregate stability. Soil testing labs now include microbial analyses, which often come with unfamiliar terms. This publication aims to educate producers, Extension agents, policymakers, and the public on how to interpret these soil microbial results to better understand their implications for soil health and crop production.