This manual was written by Dr Sam Portch of the Potash and Phosphate Institute and Dr. Arvel Hunter, president of Agro Services International Inc.

This book focuses on different aspects of the systematic approach for soil fertility evaluation and improvement. Written in the form of an operational manual, a researcher can follow the procedures in a step by step manner.

The procedures and methodology outlined in this book are the ones that we use in our lab. They have been tested and improved upon over 35 years in thousands of trials with thousands of soils.

Please contact us for a copy of this booklet.

A Systematic Approach to Soil Fertility Evaluation and Improvement


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