- Mechanical Power
- Advanced Farms
Crop Rotation is one of the breakthroughs in farming that comprised the Agricultural Revolution. It allows you to build Advanced Farms, which increase Food.
In the 7th century BC the minister of agriculture under Emperor Kuan Chung of China enacted rules regarding crop rotation for China’s peasant farmers. Greek and Roman farmers also knew crop rotation, but in all these cases the technique was very simple: leave one field fallow, plant one field. This left half the land unproductive at any given time. In 765 AD in Europe a new rotation system is mentioned for the first time: the ’three field’ system that originated in northern Europe. By this technique, a field would be planted in grains one year, legumes, oats, or lentils the second year, and left fallow the third year. This not only increased the percentage of land cultivated each year from one half to two thirds, it also provided more feed for animals and protein in the human diet in the second year. This meant more horses available to pull plows or wagons, more profit from the higher priced meat or dairy products sold by the farmer and a better diet in general for the population. Along with simultaneous developments in heavy plows, harnesses, and open field planting the new crop rotation system formed the Agricultural Revolution of the high middle ages and led to a general rise in the population of Europe from the 10th century on.