Plant crop remains from the outer burial pit of the Han Yangling Mausoleum and their significance to Early Western Han agriculture

A large amount of carbonized plant remains were discovered in one of the outer burial pits of the Han Yangling Mausoleum, which was built more than 2000 years ago for the Jing Emperor, Liu, Qi （188-141 cal a BC）, the fourth emperor of the Western Han Dynasty. The remains are identified by phytolith analysis and macrofossil morphological features. Seeds from foxtail millet （Setaria italica）, broomcorn millet （Panicum miliaceum）, rice （Oryza sativa） and chenopod （possible Chenopodium giganteum） are identified, suggesting that these four crops might have been the staple plant foods in the capital area （Guanzhong area）, Shaanxi Province during the Early Western Hart Dynasty. Chenopods were often considered as weeds since they have only been rarely found as carbonized seeds in prehistoric sites. This is the first time such a large amount of seeds has been found at a site, which provides strong material evidence for chenopod cultivation with a long history in China. Wheat was thought to be promoted and popularized in the Guanzhong area since the Wu Emporor, Liu, Che （156--87 cal a BC）, the fifth emperor of the Western Hart Dynasty. No wheat was found at this site, which supports the historical document record that wheat was still secondary in the diet and agrarian economy before the Wu Emperor＇s reign.