The most complete guide ever written on the medicinal plants of western North America. Peterson Field Guide to Western Medicinal Plants and Herbs offers the best information in the world on the current popular and traditional uses of the nearly 500 species covered—much of it available for the first time. This comprehensive guide contains more than 530 color photographs that illustrate the plants and their flowers, leaves, and fruits; the descriptive text combines scientific, ethnobotanical, and cross-cultural information. What's more, the index to medical topics is helpful for quickly locating information on specific ailments, while symbols next to the plant descriptions provide quick visual warnings for poisonous and allergenic plants. Organized by flower color for fast identification, this guide is an essential aid to appreciating native plants and the wild areas they inhabit. For more than 85 years, Peterson Field Guides have set the standard by which other field guides are measured. Comprehensive and authoritative, they are essential additions to any naturalist's bookshelf or backpack.