Abstract
Impressions of slender grains similar to those of wild Setaria species are often concomitant with foxtail millet impressions on pottery from the Neolithic to Bronze Age sites in Japan, Korea, and China. They have been identified as grains of weed species in millet fields that were mixed with harvested crop grains. However, results of threshing experiments showed that the slender floret of the wild Setaria type was a variation with unripe caryopses in cultivated foxtail millet grains and was included in the threshed and winnowed products of the experiments. Based on the morphological comparison with modern wild millets, most impressions of the slender type grains were identified as the cultivated foxtail millet. The characteristics and occurrence of grains in threshed and winnowed products including caryopses indicate that impression assemblages of foxtail millet grains originated from threshed products.
