Wu Collection, Lower Volume Radical: Cave (xué) Kangxi Strokes: 15 Page 867, Entry 12 In the Collection of Rhymes (Jiyun), it is synonymous with kiln. Furthermore, in New Discourses on Guangdong (Guangdong Xinyu), it is stated that in Guishan, there are the Yao-She people who cultivate land without plows or hoes, generally using knives to work the soil. They plant the five grains, a practice called knife-cultivation. They burn forests and trees, allowing the ash to enter the soil; the soil becomes warm, and snakes and insects die, serving as fertilizer, a practice called fire-weeding.