Is There Danger of Soil Erosion When a Rototiller Is Used on a Steep Slope?

Roots

• Rototillers rip through the soil and churn up roots to fulfill the landscaper's goal to kill weeds in the area. Although the plants are deemed weeds by the landscaper, their roots help to keep soil in place. On a slope, roots help to accumulate and hold in place soil that slides down from a higher elevation. When you remove those roots with the rototiller, you remove an element that helps to reduce erosion in the area.

Air

• Half the volume of healthy soil is solid material and half the volume is voids or pockets. Air and water pass through the voids in the soil. Plant roots need air in the soil to live and grow. Rototillers break many of the air pockets into smaller spaces. On a slope, as compared to flat land, it is more likely that, during the tilling process, soil will fall onto areas lower on the hill and compress the air spaces. Compressed soil does not have enough air to support plant life and leads to soil erosion.

Water

• Tilling the soil often reduces the amount of space water has to flow throughout the soil. If water cannot flow through the soil, it will flow over it. Water flowing over the soil carries away soil particles, along with nutrients and organic matter. Gravity amplifies the condition on a slope, causing water to move faster and carry with it greater amounts of soil. Water carves out channels or grooves as it moves over the soil, and these make it easier for more water to follow behind and erode more soil.

Alternatives

• To lessen the erosion caused by using a rototiller, till across the slope rather than up and down. Working across the slope helps to create furrows that can act as barriers to erosion. Till and plant at the same time to reduce the number of passes you make across the land. Add compost as you till, because compost encourages beneficial microorganisms to grow and release nutrients into the soil. Plant crops simply for the sake of covering the surface of the ground and producing roots to help to hold the soil in place.