Soil Erosion Checkup and Repair

Farmers are the stewards of the land, having a privilege but also a responsibility to care for this important resource that we sometimes call 'the skin of the earth.' In Pennsylvania, most farmers are also required by law to manage soil to minimize erosion by having an Erosion and Sediment Control Plan or Conservation Plan on file and to put it into practice. This plan is the responsibility of both the landowner and the farmer. The 1985 U.S. Farm Bill also requires farmers to control soil erosion on Highly Erodible Land or they may lose Federal Program benefits. However, although it is a legal requirement, soil conservation is something that farmers need to take seriously on their own because the productivity of their farm will decrease if there is excessive erosion. Fall is a good time to check fields for signs of erosion as you harvest your crops. Make a note of rills or gullies that you see, and after harvest, make sure to fix erosion problems that you observe. Further, check if any maintenance needs to be done on grassed waterways or contour buffer strips.

If you notice rills or gullies in your fields, it is important to identify the cause, fix the rills or gullies, and address the cause so they don’t form again. To fix rills or gullies, it is not necessary to till the entire field, but you do need to fill in these areas, or they will just continue to grow deeper and wider. Make sure to immediately plant a cover crop or other close-cropped vegetation to protect the soil from washing away again. Planting a winter-surviving cover crop across the area where small gullies formed is recommended. Sometimes runoff flows into a field from a culvert, road, or development, causing gully formation in your field. Special engineering structures may be needed to stop this flow from causing damage in your field.

To avoid rills and gullies from forming, you need to maximize infiltration by improving soil health and guarantee permanent organic cover, either from crop residues or living (cover) crops. Strip cropping, contour planting, contour buffers, terraces and diversions are other options to address rill and gully formation. With the advent of no-till and large farm equipment, many farmers have eliminated strips and tree lines, which sometimes has led to erosion problems. There may be times during the year when the field has very little cover, such as after corn silage or soybean harvest, while compaction caused by harvest traffic can reduce soil porosity. This can lead to excessive runoff and recurring concentrated flow paths, which can eventually turn into gullies. In such a case it may be advisable to consider breaking up the field again in strips, which should be wide enough to accommodate modern farm equipment. These need to be planted to crops that cover the field at different times of the year, such as alternating summer crops (soybeans, corn, oats) and winter crops (wheat, barley) or sod. Another option may be contour buffer strips. These are narrow strips of permanent vegetation planted on the contour, alternated with wider cropped strips also planted on the contour. If all this still doesn’t solve the problem, terraces or diversions may need to be installed. But this becomes quite an undertaking involving considerable earthmoving. In most cases, it is possible to solve your erosion problems with soil health-improving practices that include avoiding compaction and keeping the soil covered. In areas where concentrated flow or wetness is a perennial problem, for example, where a spring or seep comes out of the hillside, it may be necessary to install subsurface drainage to remove the wetness. Otherwise, it is advisable to install a grassed waterway. A grassed waterway consists of a planting of perennial sod-forming grasses that create a dense mat of fibrous roots to keep soil in place. Discuss issues or changes to your Ag E&S or Conservation Plan with your local Conservation District or NRCS professional.

Another thing to do after harvest is to check if any maintenance is needed on your grassed waterways and contour buffer strips. These permanent grass strips need to be mowed about two times a year to prevent the vegetation from becoming too tall. Relatively short vegetation prevents soil from settling out too quickly, which leads to the development of a bank at the upper end of these grassed areas, causing runoff to go around them instead of in them. This can then lead to the formation of gullies around the grassed areas. Over time, these bunds do tend to form and need to be leveled – take a disk and smooth out the lip, and reseed as quickly as possible.