There is a wonderful reference in the public domain regarding plant roots. Written in 1927, this book illustrates the root growth of many vegetables in a variety of conditions. sustainablefarmer.com has made this book available online at http://www.sustainablefarmer.com/pdflibrary/library-rootdevelopment.pdf. While the book focuses on the locale of Lincoln, NE and Norman, OK – it’s information is notworthy for any gardener.
- Modifying the root environment
- Adaptation of roots to environment
- Root adaptation and crop production
- Interrelations of plant, soil, and climate
- Activities of roots in subsoil
- Number and size of plants
Read more at http://gardenhacker.com/hidden-world-of-plant-roots/