The only place in the world today where American groundnuts are commercially farmed in any significant quantities is in Japan. Before the American groundnut was introduced to Japan, the people on the main island of Honshu and the northern island of Hokkaido were already familiar with a native, wild plant called hodoimo (Apios fortunei), which was occasionally eaten as an emergency food. It is believed that sometime during the Meiji period (1868-1912), American groundnut was accidentally or deliberately brought to Japan. One theory is that American groundnut was accidentally brought to Japan as a stowaway weed among apple seedlings imported from North America. Another theory is that American groundnut may have been deliberately brought to Japan in the middle of the Meiji period as an ornamental flower.