Food production
The primary Neolithic crops, domesticated by the 5th millennium bce, were drought-resistant millet (usually Setaria italica), grown on the eolian and alluvial loess soils of the northwest and the north, and glutenous rice (Oryza sativa), grown in the wetlands of the southeast. These staples were supplemented by a variety of fruits, nuts, legumes, vegetables, and aquatic plants. The main sources of animal protein were pigs, dogs, fish, and shellfish. By the Bronze Age, millet, rice, soybeans, tea, mulberries, hemp, and lacquer had become characteristic Chinese crops. That most if not all of these plants were native to China indicates the degree to which Neolithic culture developed indigenously. The distinctive cereal, fruit, and vegetable complexes of the northern and southern zones in Neolithic and early historic times suggest, however, that at least two independent traditions of plant domestication may have been present.
The stone tools used to clear and prepare the land reveal generally improving technology. There was increasing use of ground and polished edges and of perforation. Regional variations of shape included oval-shaped axes in central and northwest China, square- and trapezoid-shaped axes in the east, and axes with stepped shoulders in the southeast. By the Late Neolithic a decrease in the proportion of stone axes to adzes suggests the increasing dominance of permanent agriculture and a reduction in the opening up of new land. The burial in high-status graves of finely polished, perforated stone and jade tools such as axes and adzes with no sign of edge wear indicates the symbolic role such emblems of work had come to play by the 4th and 3rd millennia.