By about 500 BC rice agriculture was being practised in Kyushu, although it is possible that rice was being eaten before that, as rice grains have been discovered from the later part of the Jomon period as both impressions in pottery and as phytoliths (identifiable minute silica particles from plants).
Some rice grains have been identified at the later Jomon site of Kazahari in north-eastern Japan, and it is also possible that rice was being traded.
Japan is the northernmost area in which rice was grown. Rice cultivation seems to have entered Japan from southern China via the Korean peninsula, but it is also possible that it came along a more northerly route via the Shandong and Liaodong peninsulas and then down Korea.
First cultivated in south-western Japan, it then spread east to the Kinai region, before being taken up all over Honshu by the end of the Yayoi period around AD 300.
In some areas, however, it was not possible to grow rice, and millet may have been very important. Rice was only one of the crops grown by Yayoi farmers, others including barnyard and foxtail millet, barley, wheat, buckwheat, hemp, azuki bean, soyabean and pea, and soft fruits such as plum and pear.
