The Qimin yaoshu 齊民要術 "Important methods to condition the people's [living]" is one of the oldest agronomical treatise of China. It was written by Jia Sixie 賈思勰, a scholar of the short Eastern Wei period 東魏 (534-550). He came from Yidu 益都, modern Shandong, and was governor (taishou 太守) of the commandery of Gaoyang 高陽. He had the opportunity to observe the farming activities in the regions of Jingxing 井陘, Huguan 壼關 and Shangdang 上黨 (all in modern Shanxi and Shaanxi) and was himself a breeder of sheep.
The Qimin yaoshu comprises 92 chapters in 10 juan "scrolls". About the author virtually nothing is known but in his foreword he at least explains that he collected quotations from all types of books, especially from older agronomical treatises like the Fan Shengzhi shu 氾生之書 and the Simin yueling 四民月令 as well as interviews of experts on agronomy.
Jia Sixie does not only describe how to plant and rise different kinds of crops or how to breed cattle, but also describes the preparation and storage of some materials based on agronomical products, like wine, glue, oil, fibres, dyestuffs, ink, or cooking products processes (pickling) and products like yeast, sugar and soy sauce (juan 7 to 9). Besides staple food (juan 1-2) he explains the cultivation of vegetables (juan 3), fruits and mulberry trees (juan 4), the latter's leaves being used as fodder for silkworms. Juan 6 describes cattle breeding and fish-farming. In juan 10 he also describes plants not common in central China, and his book is thus a very important source for agriculture in early China. Jia Sixie quotes from more than 150 ancient books and so preserved many fragments of texts that are otherwise lost (Fan Shengzhi shu, Simin yueling or Tao Zhugong's 陶朱公 Yangyujing 養魚經), and also many country sayings (geyao 歌謠). The "Miscellaneous Chapter" (Zashuo 雜説) and the chapter Huozhi 貨殖 "Trade" has been added later.
The Qimin yaoshu is the oldest completely surviving agricultural text of China. Jia Sixie stresses the importance of agriculture for the welfare of society and the whole state, and supports his argument by quotations from ancient masters like Ren Yan 任延, Wang Jing 王景, Huangfu Long 皇甫隆, Ci Chong 茨充, Cui Shi 崔寔, Huang Ba 黄霸, Gong Sui 龔遂 and Shao Xinchen 召信臣. Further proofs of this assumption come from the chapter Hongfan 洪範 of the Shangshu 尚書 "Book of Documents" and other Confucian Classics where the kings of the Zhou dynasty 周 (11th cent.-221 BCE) are admonished to "appease, enrich and instruct the people". Compared with older agronomical texts like the Fan Shenzhi shu from the Han period 漢 (206 BCE-220 CE) the scope of agricultural fields is widely enlarged in the Qimin yaoshu. It includes not only the cultivation of plants, but also cattle breeding, forestry and the processing of products. A successful farmer, Jia Sixie says, would not only mechanically do his work, but would critically observe the seasons, weather, and the quality of the soil, in order to adapt his work to these factors. Such a method would save labour and increase yields (yong li shao er cheng gong duo 用力少而成功多). For the amelioration of the soil, better ploughing methods had been developed, in combination with the selection of better seeds. Jia Sixie therefore describes 86 of various seeds in his book. For the windy and dry spring season of northern China he recommended deep-ploughing for the first cultivation of a field, but a shallow reverting of the soil in autumn, and vice versa. Between phases of cultivation it was profitable for the preservation of moisture to level the ground and to weed out undesired grasses. Crop rotation, he says, also help to keep the fertility of the soil. Green beans (lüdou 緑豆) planted first would enrich fertility, and had to be followed by small beans (xiaodou 小豆) or sesame (huma 胡麻). Besides methods of sowing the author also describes different methods of plant propagation like striking (qiancha 扦插), stolons (yatiao 壓條), division (fenzhu 分株) or propping (jiajie 嫁接). The author seems to not have highly estimated a kind of marketization of agricultural products, as advocated by the late Han period scholar Cui Shi (Simin yueling), but he rather preferred a kind of self-subsisting farming for a single—although large—household.
The oldest surviving print of the Qimin yaoshu dates from the Northern Song period 北宋 (960-1126, printed by the Institute for the Veneration of Literature, Chongwenyuan 崇文院), but only 4 scrolls are preserved in Japan. The Qimin yaoshu is to be found in the collectanea Siku quanshu, Sibu congkan 四部叢刊, Mice huihan 祕册彙函, Jindai mishu 津逮祕書, Sibu beiyao 四部備要, Wanyou wenku 萬有文庫, Xuejin taoyuan 學津討原 and Jianxi cunshe congkan 漸西村舍叢刊.
There are two 20th century commentaries to the Qimin yaoshu, namely Shi Shenghan's 石聲漢 Qimin yaoshu jinshi 齊民要術今釋 and Miao Qiyu's 繆啟愉 Qimin yaoshu jiaoshi 齊民要術校釋.
Lin Qitan 林其錟 (1994). "Qimin yaoshu 齊民要術", in: Zhongguo xueshu mingzhu tiyao 中國學術名著提要, Jingji 經濟, Shanghai: Fudan daxue chubanshe, p. 96.
Miao Qiyu 繆啟愉 (1990). "Qimin yaoshu 齊民要術", in: Zhongguo da baike quanshu 中國大百科全書, Nongye 農業, Beijing/Shanghai: Zhongguo da baike quanshu chubanshe, vol. 1, p. 865.
Wang Guozhong 王國忠 (1996). "Qimin yaoshu 齊民要術", in: Zhongguo xueshu mingzhu tiyao 中國學術名著提要, Keji 科技, Shanghai: Fudan daxue chubanshe, p. 387.
Zhou Yiliang 周一良 (1992). "Qimin yaoshu 齊民要術", in: Zhongguo da baike quanshu 中國大百科全書， Zhongguo lishi 中國歷史, vol. 2, p. 764. Beijing/Shanghai: Zhongguo da baike quanshu chubanshe.