Eroding away your economic and environmental progress
Controlling erosion on your farm is good for the environment but also your pocketbook.
The Natural Resources Conservation Service (NRCS) defines erosion as, “the breakdown, detachment, transport, and redistribution of soil particles by forces of water, wind, or gravity.” Soil erosion has many implications for both cropland and land utilized by livestock. Soil quality and crop yields may be negatively affected along with potential impacts to water quality. This means the sustainability of the economic and environmental portions of a farm are put in jeopardy.
In recent years, more intense and heavy precipitation events have been documented leading to an even greater need to prevent soil erosion both on and off the farm. Several conservation practices exist to help control soil erosion: cover crops, vegetative filter strips, tillage practices (no-till and conservation tillage), crop residues, and grassed waterways, to name a few.
In a Michigan State University Extension news article, "Controlling soil erosion with cover crops," outlines some of the benefits of cover crops in controlling soil erosion. Living roots hold the soil in place, maintaining soil integrity during rain and wind events. For more information on this, check out the MSU Extension article, "Cover crops are effective at reducing impacts of wind erosion in high wind events." Additionally, the canopy of the cover crops helps protect the soil from direct rainfall, which has the potential to displace soil particles, leading to higher amount of soil erosion.
Vegetative Filter Strips
The use of a narrow strip of grasses or other permanent vegetation to reduce sediment and nutrient loss to nearby water bodies is known as a vegetative filter strip. Much like cover crops, the roots from vegetative filter strips bolster the soil’s ability to stay in place even during larger water flow events. Additionally, some vegetative filter strips can be utilized as short-term grazing sections or harvested for other uses. Management of these strips is particularly important as improper management may lead to problems with nuisance plants, high nutrient levels, or sheet flow.
The type of tillage used has a direct impact on soil health. The more tillage carried out on a field, the greater the chance of seeing erosion caused by water and wind. Additionally, conventional tillage practices can lead to a greater chance of soil compaction and sealing, which reduces the soils water infiltration and holding capacity. It is important to remember that every farming system is different and what might work for one farm in regards to tillage practices may or may not work for another. For more information about different tillage practices, contact your local MSU Extension Field Crops Educator.
Leaving crop residues on fields after harvest has the ability to help protect the soil against erosion and help build soil health. The amount of residue left on the field will depend on your farming system. Too much residue may prevent early soil warming, though, according to Xingli Lu, Northwest A & F University, Xianyang, China, "A meta-analysis of the effects of crop residue return on crop yields and water use efficiency," residue does not appear to have long-term effects on yield. However, removing too much residue may increase the risk of soil erosion and lead to negative impacts on soil organic matter. Much like cover crops, allowing for some remaining crop residues provides protection to the soil against direct rainfall, which can displace soil particles leading to soil erosion.
Grassed waterways are utilized in situations where gully erosion is present. Typically, in these areas of a field, it is very difficult to grow crops due to washouts that happen during large precipitation events and snowmelt. By shaping the earth and planting grass or other recommended vegetation, it helps to not only potentially capture nutrients, but also sediment from soil erosion. The root system formed by these plants help to hold the soil in place and reduce the risk of erosion. This system needs to be engineered and managed properly. Consequently, follow the management plan designed by NRCS for the practice to make sure management is done in an appropriate manner.
Other Helpful Resources for Dealing with Soil Erosion
The Revised Universal Soil Loss Equation 2 (RUSLE2) is a tool to help estimate soil loss from rill and interrill erosion. To put it simply, rill and interrill erosion occurs when rainfall or runoff causes the removal of layers of land from the land surface.
Another tool to help estimate soil loss due to erosion on your farm is the Michigan Sensitive Areas Identification System (SAIS). Using SAIS allows you to see reports for specific fields with different maps that examine soil type, sediment delivery, sheet and rill erosion, wind erosion, concentrated flows, and more.
Additionally, the Michigan Agriculture Environmental Assurance Program (MAEAP) is a voluntary program that helps farms of all types and sizes to assess environmental risks associated with agricultural practices. Some of the recommendations that MAEAP outlines in their assessments (Farmstead, Cropping, Livestock, and Forest, Wetlands and Habitat) help address potential soil erosion and how to remediate some of those risks.
Finally, MSU Extension is also here to help answer any questions you may have regarding soil health and erosion on your farm. Contact your local Extension Educator for more information.