| title | ISBN-13 | year of publica-
tion |
|---|
| Field Guide to the Wild Orchids of Texas | 978-0-8130-3159-0 | 2008 |
| Ladies'-tresses in Your Pocket: A Guide to the Native Ladies'-tresses Orchids, Spiranthes, of the United States and Canada | 978-1-58729-656-7 | 2008 |
| Lady's-slippers in Your Pocket: A Guide to the Native Lady's-slipper Orchids, Cypripedium, of the United States and Canada | 978-1-58729-655-0 | 2008 |
| The Wild Orchids of North America, North of Mexico | 978-0-8130-2571-1 | 2003 |
| Wild Orchids of Florida, Updated and Expanded Edition: With References to the Atlantic and Gulf Coastal Plains | 978-0-8130-2933-7 | 2006 |
| Wild Orchids of the Canadian Maritimes and Northern Great Lakes Region | 978-0-8130-2911-5 | 2006 |
| Wild Orchids of the Northeastern United States: A Field and Study Guide to the Orchids Growing Wild in New England, New York, and Adjacent Pennsylvania and New Jersey | 978-0-8014-8341-7 | 1997 |
| Wild Orchids of the Northeast: New England, New York, Pennsylvania, and New Jersey | 978-0-8130-3034-0 | 2007 |
| Wild Orchids of the Pacific Northwest and Canadian Rockies | 978-0-8130-2900-9 | 2006 |
| Wild Orchids of the Prairies and Great Plains Region of North America | 978-0-8130-2975-7 | 2006 |
| Wild Orchids of the Southeastern United States, North of Peninsular Florida | 978-0-8130-2749-4 | 2004 |