Researched
Crop rotation (Norfolk system)
Alternating cereals with clover and turnips fed livestock and restored soil fertility, ending the fallow year in 18th-century England.
Open in the interactive tree →The Norfolk four-course system (wheat, turnips, barley, clover) spread in 18th-century Britain together with Jethro Tull's seed drill (1701) and systematic livestock breeding. Clover enriches the soil with nitrogen, though the mechanism was not understood until the 1880s. Higher yields released labour for industry and cities.
Prerequisites
- Three-field rotation~800
- Scientific Method~1600-1620
- Seed Drill1701Row sowing allowed hoeing; turnip and clover rotations spread with the drill