This book contains descriptions and uses of hundreds of useful plants and is probably the most imporant book to have in your edible plant book collection. It also gives fair warning when some evidence suggests possible risks.
Despite these points, there are some things that make it hard to use. First, because they are trying to cram in as many plants as possible, they don't give enough attention to many plants that deserve it and give very breif descriptions, although they do point out some of the main identifying features. Second, the pictures, at least for the first half of the book, are simply recycled from the Peterson Guide to Wildflowers, which means that they often leave out important parts that you really need to see. Third, the book is organized for the most part so that you can't find a plant unless you know the color of the flower, which makes it really difficult to recognize plants unless you find them during the period they flower, which is usually pretty short. And did anyone notice that they switched the pictures of Nodding Wild Onion and Field Garlic on page 115?
Of course, the descriptions and drawings are better than most books on the subject, and it does have many useful features, so this book is definately worth having.