Every field of study has its own "bible" and I believe this book is the must-have tome for fern-lovers. The botany presented in the structure and life history sections is sound and well presented. The care - and particularly the propagation - section is tremendous ... the most thorough treatment I've seen. The back half of the book is an encyclopedic account of species rife with color photos. Tropical and temperate ferns are trated equally without bias toward the temperate gardener or indoor collector.
The only area not covered in exacting detail is classification and phylogeny, but since there is little scientific concensus in these areas, the short shrift is forgiveable.
The bibliography is outstanding. Jones did his homework! There are a couple hundred references there to fascilitate further, more narrow research.
If you're a fern-lover, you could live without this book...but why would you want to?