Mount Toby is considered one of the most biodiverse areas in New England. Fern and orchid species are particularly prolific on the mountain; forty-two of forty-five possible native fern species grow there as do rare orchids such as the Showy Lady Slipper and the Ram's Head Lady Slipper. Unlike the surrounding region, Mount Toby was never cleared of its timber during New England's intensive agricultural period in the 18th and 19th centuries; it has remained wooded throughout, although timber harvesting has played a part in its history.