When properly maintained, soil is a renewable resource, which is why practicing sustainable agriculture methods is crucial. If your land is on a slope, you can conserve nutrient-rich soil by using contour plowing. Unlike straight furrows, contours reduce water runoff and erosion caused by wind. As a result, soil nutrients are retained.
Ridges and Furrows
Contour farming is plowing across the slope, creating ridges and furrows. You can do that through tillage, planting or other farming practices to force the water to go around the slope instead of down the slope. The elevated contour lines you create slow down water runoff by retaining and absorbing most of it after a rainstorm.
The Purpose
The essence of contour farming is to prevent soil erosion because the contours increase water infiltration. Contour farming is done on hilly land where crops are grown annually. When practicing this type of farming, you must ensure the soil grade is suitable to prevent water from pooling, which can damage crops.
Types of Soil
The effectiveness of the contours are influenced by several factors, including the ridge height, steepness, length of the slope and the hydrologic soil group. The soil groups determine the minimum rate of infiltration after a rainfall. Group A soils have a high rate of infiltration and allow water to easily move within the soil. With that type of soil, soil conservation can easily be attained through contour plowing.
The Length of the Slope
Contour plowing works better on slopes with gradients ranging from 2 percent to 10 percent. The slope must be between 100 and 400 feet long for contour plowing to be effective. Longer slopes are ineffective because the velocity of overland flow is too much for the contour ridges to contain. All these are factors you must taken into account before practicing contour plowing.
