Book excerpt: More than 100 mushrooms in the genus Tricholoma have been reported in North America. Most are relatively large, showy mushrooms that grow on the ground near many species of temperate forest trees, both hardwoods and conifers. They typically fruit from late summer through early winter or even into spring in warmer areas. Some are fine edibles, including the matsutake. Others are inedible or even poisonous. Filling the gap between technical publications and the limited representation of Tricholomas in general mushroom field guides, this book is the first comprehensive guide to North American Tricholomas. It contains more than 170 of the best documentary photographs available, often with more than one image of a species to illustrate the dramatic variation exhibited by many Tricholomas. The species descriptions provide extensive identification information including scientific and common names, macroscopic and microscopic features, occurrence/habit, edibility, and a comment section that addresses such things as synonomy, comparisons with similar species, varietial differences, explanations of species' epithets, and other useful or interesting information. In addition, the authors provide a general introduction to Tricholomas that discusses identification features, ecology, simple chemical tests (for identification), and how to use the keys provided in this book.