《吕氏春秋·论·士容论》
辩土耕地的原则是：一定要从垆土开始，因为这种土水分少，干土层厚。
五曰：凡耕之道，必始于垆，为其寡泽而后枯。
The principle of farming on different kinds of land is: one must start from the soil, because this kind of soil has less water and a thick dry layer.