Sequestering carbon and increasing productivity by conservation agriculture

Cast iron plow (blacksmith John Deere, 1830s) Moldboard plow in United States (Thomas Jefferson, 1784, patented by Charles Newfold in 1796) Moldboard plow (Middle Ages) Coulter plow to cut a strip (~1000 AD) Plow with iron share (Europe, 5 th century AD) Roman plow (Virgil, 1 AD) Ard or a forked stick (4000 to 6000BC) Soil type and origin of tillage Gravelly/stony soils Hoe Conservation tillage (30% of the soil surface covered by residues) Alluvial soils