chapter 474 Dagny Ding’s new idea ===

The best method for farming was to establish an ecological chain. The combination of wild duck manure and decaying leaves created a good feed for earthworms. Then, earthworms, in turn, became a nutritious food source for wild ducks. Moreover, earthworms grew and reproduced quickly. They could rely on reproduction to sustain the population, thus reducing the cost of feeding wild ducks. Through careful calculations, Dagny estimated that the cost of raising each wild duck could be reduced by about...