A majority of the current literature on the ubiquitous and life-sustaining symbiotic relationship between plant roots and fungi (mycorrhizas) focuses on ecological, molecular, and physiological studies, according to Peterson (botany, U. of Guelph, Ontario). Based on new analytical methods, this volume by Canadian scientists summarizes mycorrhizal categories and unresolved issues (eg, whether nutrients can pass through the fungal mantle) from a structural perspective. Features include a glossary and appendices outlining laboratory methods used in the preparation of the featured color and b & w images. Annotation: 2004 Book News, Inc., Portland, OR (booknews. com).