Zenong yaolu 澤農要錄

Zenong yaolu 澤農要錄 a book on rice cultivation in north China written by Wu Bangqing 吳邦慶 (1768-1848), courtesy name Jifeng 霽峰, from Bazhou 霸州, Zhili (today's Hebei). His highest office was Director of the Grand Canal in Hedong (Hedong hedao zongdu 河東河道總督).

Wu's motivation for writing this book was to spread the knowledge of rice cultivation in south China to the Yellow River plain. The Zenong yaolu consists of 6 juan divided into ten chapters on farming with the seasons (Shoushi 授時), field allotment (Tianzhi 田制), seed classification (Bianzhong 辨種), land clearance and ploughing (Gengken 耕墾), planting and replanting (Shuyi 樹藝), weeding and sowing (Yunzi 耘籽), preparing the soil (Peiyong 培壅), irrigation (Guangai 灌溉), use of water (Yongshui 用水), and harvesting (Shouhuo 收獲).

The book describes the complete process of rice production, from land reclamation to farming, seed selection, sowing, fertilisation, irrigation, harvesting, and storage. The text is composed in a traditional way, with quotations about rice production, as found in ancient books. Yet, the author adds his private recommendations and conclusions before each chapter. The author points out that the North China Plain was rich in water resources, which only had to be made use of consequently to implement southern types of rice fields, like "embanked fields" (weitian 圍田), "chest fields" (guitian 柜田), seashore fields (tutian涂田), terraced fields (tidian 梯田), "frame fields" (jiatian 架田) or "sand fields" (shatian 沙田) in the north.

Wu stated that local gazetteers in north China used many names and designations for dry-rice and even wet-rice for hundreds of years. It was, therefore, necessary to revive irrigation projects to expand wet-rice cultivation. However, because of local conditions, it was in the dry lands of north China necessary to rotate crops such as wet-rice and maize if dry rice had not been cultivated for several years. The book emphasises that farmers cultivating wet rice should pay attention to preparing fields, manure, seeds, and irrigation methods. He also proposed the idea of implementing hydraulic projects reasonably by considering the terrain conditions, the water potential, methods to remove obstacles or size, and the project's urgency.

The book was finished in 1824 and is included in the series Jifu hedao shuili congshu 畿輔河道水利叢書.