Middle AgesEconomy & Trade Heavy plow and crop rotation c. 800 CEMajor The heavy plow and three-field rotation boost harvests on Europe's heavy northern soils. ▲ MattersSaveShareTrace roots Longest chain: The Big Bang → First stars ignite → Supernovae seed heavy elements → The Sun forms → Earth forms → First oceans → First life → Photosynthesis evolves → Great Oxidation Event → Complex cells (eukaryotes) → Multicellular life → First animals → Cambrian Explosion → First vertebrates → Jawed fish → Fish walk onto land → The amniotic egg → The Great Dying → Dinosaurs appear → Asteroid ends the dinosaurs → Early primates → Apes split from monkeys → Human line splits from chimpanzees → Walking upright → First stone tools → Genus Homo appears → Homo erectus → Control of fire → Habitual fire and cooking → Homo sapiens appears → Complex language → Natufian villages → Oldest known bread → Agriculture begins → Sheep and goats domesticated → Cattle domesticated → Ox-drawn plow → Heavy plow and crop rotation Community notesLoading notes… Learn more ranked by votesDocumentbritannica.comThree-field system (Britannica) ↗Editor's pickDocumentbritannica.comWheeled plow (Britannica) ↗Editor's pickBookLynn White Jr.Medieval Technology and Social Change ↗Editor's pickVideoSearch on YouTubeheavy plough three field system medieval ↗Editor's pick