Have you ever drove past a farm and seen a farmer tilling the fields? When they till (also known as cultivate and plow), they are moving around the soil particles, slicing into the soil, pushing the soil around, or flipping the top soil layer.
In the days of old, people would plant seeds in small holes they made in the soil. They would use their hands to pull up weeds. Occasionally, they would use a shovel to mix in nutrients. These days, though, farmers use tractors. Small gardeners tend to use a rototiller that moves the soil around for them. Why do they till the soil, though?
One reason the farmers till the soil is for weed control. They want to destroy the roots of the weeds. Another is to prepare the seedbed. Tilling can help the soil become more favorable for the seeds. And last, for incorporating different sources of fertilizers in the soil. Occasionally, farmers will also till to help control water evaporation from the soil. Is tilling really necessary though?
In the United States, the Dust Bowl was created from drought and farmers tilling the land too much, leaving the soil dry and bare. The wind blew and took away the topsoil. This taught us that too much plowing can hurt the soil. It can decrease the organic matter of the soil and keep it from holding water. Because of this incident, scientists started looking for some better ways that would protect the soil. They found that when farmers leave plant residue on the surface of the soil, it helps to protect it from rain and wind. Also, when the soil isn’t disturbed, the organic matter is helps the soil to recover and better resist erosion.
A lot of farmers will now leave the residue from the plants and till less than in the past. They can use equipment that allows them to plant seeds into unplowed soil now as well. They are beginning to understand that soil that is tilled is less healthy. Hopefully, they will continue to listen to the research in this matter and change their practices to keep the soil healthy.