Popular, proven series: More than 525,000 copies of the Nature Study Guides have sold Market: campers, gardeners, foragers, hikers, and anyone who appreciates nature's wonders Foraging is on the rise; this is a perfect first step toward becoming a forager Step-by-step, dichotomous guide to general fungi identification Not intimidating--easy-to-use information geared toward casual observers More than 300 types of fungi Applicable to mushrooms that are or look like a fungus, that are at least 5mm tall or wide, that have feelable thickness in all directions, and that are still fresh Aimed at breadth rather than depth--so you're likely to find the content that you're looking for, but you might not be able to identify a given fungus to its specific species or genus Professional illustrations carefully drawn with key markings to aid in field identification Small (5.88- by 4-inch) format that fits in a pocket or backpack Perfect beginner's tool to field identification (not a guide to edible mushrooms) Covers the continental United States and Canada Wonderful impulse purchase--less than $10 per book About the series creator: May Theilgaard Watts, born in 1893, was an esteemed naturalist and celebrated ecologist. She was a longtime naturalist at the Morton Arboretum (retired in 1961) and is credited with proposing in 1963 what developed into our national rails-to-trails program. She is considered an early figure of influence in prairie restoration and is regarded as an influential figure in helping the public rethink its relationship with the natural world. The concept of the "finder" dichotomous key (which is at the center of this series) began with May; she created student handouts in the 1930s, which evolved into the pocket guides. About the series: In the 1960s, May's son Tom Watts turned the handouts into a business venture (Nature Study Guild), which he operated with his wife in Berkeley until his death in 1992. After Tom's death, his daughter Bridget moved the business to Rochester, New York, and operated it there until Keen purchased the rights to the line in 2014. The series' fresh design is more cohesive while maintaining the artistic appeal of the original books.

Series updates include range maps, scientific names, species lists, and more. Naturalists and educators like the books because they get people to look at the structures of objects and to look at the families, as well as specific species. Displays are available specifically for this series. In 2023, more than 60,000 units sold of the 14 Nature Study Guides currently in print. With more than a million copies sold, Nature Study Guides have helped people across the US and Canada learn about and connect with nature.