Experiments on the management and propagation of wild azuki bean (Vigna angularis) populations using fire: Toward understanding the management of wild azuki bean populations by Jomon people in prehistoric Japan

Nasu, H., Takada, H., Yamada, M.

20th Conference of the International Work Group for Palaeoethnobotany

International Work Group for Palaeoethnobotany

Groningen, The Netherlands

This paper presents an experimental study examining the possibility that hunter-gatherers of the Jomon period in Japan used fire to manage and propagate wild azuki bean populations. Azuki bean seeds have been found at Japanese Jomon sites for 10,000 years, suggesting that the use of wild azuki bean began when the Jomon people started seasonal settlement. Seed size gradually increased from the Middle Jomon period (ca.5,000 cal BP), when many long-term settlements were found, and a rapid increase in seed size was observed in the Late Jomon period (ca. 4,000 cal BP), suggesting that domestication had occurred. However, no traces of arable land have been found at Jomon sites, and no clear farming tools have been found. We hypothesize that the Jomon people managed wild populations of azuki beans in a manner different from farming or cultivation, and have been conducting experiments to this end since 2016. In our experiments, we have successfully managed and propagated wild azuki bean populations by mowing and burning in the spring on the field where wild azuki grows naturally. Fire-cutting is thought to eliminate competitors in the early growth stages of wild azuki bean, increase nutrients, as well as promote germination due to heat. Perhaps the Jomon could have managed the legume they needed for their own needs by mowing and fire burning, even without cultivation.