The Asteraceae, often referred to as the sunflower family, are one of the largest flowering plant families in the world, containing over 20,000 species. The family reaches its maximum diversity in temperate zone. In Ohio, 75 genera and 276 species are represented in the flora. The Dicotyledoneae of Ohio is a comprehensive study of the sunflower family as it is known to exist in the state today. Dr. T. Richard Fisher traveled the state extensively for thirty years in order to observe and study the many species in their habitats as well as specimens represented at the larger herbaria in Ohio. Fisher has constructed keys to aid in the identification of species and provides complete illustrations, ecological habitat descriptions, and distribution maps showing abundance and flowering period. Several alternative types of keys are provided for readers with varying levels of experience. For example, Fisher offers basic descriptive information for the layperson, while the more experienced student can begin at the generic descriptive key. Each species has been fully described and illustrated, with emphasis on detailed identifying features and a discussion of the abundance and ecology of species. T. Richard Fisher is Professor Emeritus of Biology at Bowling Green State University (Ohio). He is the author of Introduction to Horticulture and numerous articles.