This story is a supplement to the feature "No-Till: How Farmers Are Saving the Soil by Parking Their Plows" which was printed in the July 2008 issue of Scientific American.
The roots of both no-till and tillage-based farming methods run deep, but eventually the latter approach predominated, thanks to the evolution of the plow. Over the past few decades, however, advances in herbicides and machinery have made no-till practical on a commercial scale.
Planting stick, the earliest version of no-till, enables the planting of seeds without cultivation.
Scratch plow, The earliest plow, clears a path through the ground cover and creates a furrow into which seeds can be placed.
Draft animals replace humans in powering the plow.
Plowshare, a wedge-shaped implement tipped with an iron blade, loosens the top layer of soil.
Moldboard plow has a curved blade (the moldboard) that inverts the soil, burying weeds and residues.
Steel moldboard plow invented by John Deere in 1837, is able to break up prairie sod.
Tractors can pull multiple plows at once.
Herbicides such as 2,4-D,atrazine and paraquat enable farmers to manage weeds with less tillage.
No-till seeders slice open a small groove for seeds, keeping soil disturbance to a minimum.