Soils are one of the world’s most important resources; protection, maintenance, and improvement of this resource is critical to maintaining a quality life on earth. It is the hope that understanding and application of information in this book will help to increase the world’s food supply, but at the same time allow the soil resource to be protected for many generations. On the other hand, plants are valuable eresources for all living organisms existing on planet Earth. The world-wide shortage of plant production menacing the survival of many people demands for more and better research, particularly on how to increase food and where it is most needed.