The plow is a global symbol for agriculture. The earliest plow was likely a large stick drug across the ground. Light, wheelless plows drawn by oxen with iron blades replaced sticks by ancient Roman times. Plowing with iron blades reached Northwestern Europe when the wheeled plow was invented.¹ Not much changed in the design of plows until 1797 when Charles Newbold patented the first cast-iron plow. Interestingly enough, farmers did not trust this new plow as they thought it would “poison the soil” and encourage weed growth.² 40 years later in 1837, John Deere invented the cast-steel plow tough enough to rip through American prairie turf. Today, farmers and ranchers can choose from a variety of different plows: the moldboard plow,  disc plow, chisel plow, rotary plow, and others.

Plowing, and its less intensive cousin, tilling³, have been common practice in human agriculture for millennia, but, unfortunately, soil degradation follows in its wake. I will use the term “tillage” to refer to plowing or tilling events from now on. Tillage events set off a chain of events that decreases soil health over time. Collapse of soil health leaves a community, country or empire vulnerable to famine and social unrest. For those interested, David Montgomery’s book Dirt: The Erosion of Civilizations is an incredible read on the role soil degradation played in the collapse of the Egyptian, Greek, and Roman empires, as well as its effect on modern civilization, like the self-inflicted U.S. Dust Bowl of the 1930’s.