Cropland Management

Cover Crops

cover cropCover Crops are grasses, legumes or forbs planted to provide seasonal soil cover on cropland when the soil would otherwise be bare. In Minnesota, the cover crop is commonly rye, although oats, barley, alfalfa, buckwheat and hairy vetch are also used. The short growing season in Minnesota limits the use of cover crops although use is expanding as farmers are seeing the environmental and financial benefits of the practice.


Cover crops can be categorized into five main categories with winter cover crops and catch crops being the most commonly used:

  • A winter cover crop is planted in late summer or fall to provide soil cover over winter. In Minnesota, winter cover crops are commonly planted after potato
    harvest primarily to reduce wind erosion.
  • A catch crop is a cover crop planted after harvesting the main crop, primarily to reduce nutrient leaching.
  • A smother crop is a cover crop planted primarily to outcompete weeds. In Minnesota, buckwheat and rye cover crops commonly serve this purpose.
  • A green manure is a cover crop incorporated into the soil while still green, to improve soil fertility. Currently in Minnesota, green manures are used primarily by organic growers.
  • Cover crops can serve as short-rotation forage crops when used for grazing or harvested as immature forage (green chop).


Water quality benefits of cover crops come from three processes. The first is the literal cover that the crop provides to the soil, reducing erosion from raindrop impact. The second is the potential for the cover crop to take up nutrients that would otherwise be lost from the field through surface or drainage water and the third is increasing soil infiltration.


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Nutrient Management

nutrient managementNutrient management is the management of the Amount, Method, and Timing of applications of fertilizers, manure, and other soil amendments. The nutrients that have the greatest impact on water quality are nitrogen (N) and phosphorus (P). Nutrient management BMPs are one of the most effective ways to improve water quality because of the extent of nutrient related water quality issues. Nutrient Management is one of the most common BMPs used on farms state-wide and is recognized as a practice that can be implemented on almost every farm.


Excesses of both N and P can adversely affect our aquatic systems, driving new water quality standards and efforts to prevent further impairment of water bodies. N applied in agricultural fields poses a potential threat to human health when excessive levels of the nitrate form of N find their way into drinking water sources. Agricultural fertilizers are also a major contributor of nitrates to the Gulf of Mexico where they cause seasonal hypoxia.


The keys to effective crop nutrient management are developing and following a yearly plan and conducting soil tests to determine the nutrient needs of crops. (Increasingly, soil nitrate testing before applying fertilizer and plant tissue testing are also used.) It is essential to keep good records on the rate, method and timing of all nutrient applications. It is also important to note the source of the nutrients, be they purchased fertilizers, manure or other bio-solids, legumes or irrigation water. Residual nutrients in the soil must also be accounted for. Keeping good records help farmers compare expenses and returns from year to year. In short, good records provide solid information that helps farmers and crop consultants decide whether and how to adjust nutrient application rates, methods and timing.


Another important element of nutrient management is to consider the application rates recommended by private or public sector specialists. In 2006, the University of Minnesota Extension estimated that 86% of Minnesota farmers could save more than $6/acre and 56% could save more than $10/acre in fertilizer costs by following UM recommended rates. This was based on calculations by roughly 700 Minnesota farmers who prepared their own nutrient management plans at Extension workshops.


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Organic Farming

organic"Organic" is a guarantee about how an agricultural food or fiber product was grown and handled before it reached the consumer. It's also a set of standards for farmers who grow plants and animals, and for processors and handlers who turn it into food or clothing products.


Farmers and food processors that make organic claims must meet national organic standards, maintain careful records, and be certified by an USDA accredited organization, a process that includes on-site inspections, however, farms that gross less than $5,000 in organic sales may be exempt from certification.


The number of certified organic farms and acres in Minnesota is continuing to grow, along with the domestic and international market demand for organic food. Minnesota has more than 500 certified organic farms and more than 130 certified organic food processors and businesses. Organic continues to be one of the most rapidly growing sectors in the food industry. Benton SWCD has also identified an increase in the amount of interest from Benton County landowners.


The following resources can be found at our office:

  • 2006 Status of Organic Agriculture in Minnesota Report to the Legislature
  • List of USDA Accredited Organic Certifiers Active in Minnesota, 2007
  • Organic Certification fact sheet
  • How to Choose an Organic Certification Agency fact sheet
  • Transitioning to Organic Dairy Production fact sheet
  • Common Mistakes Made by Organic Certification Applicants fact sheet


Online resources include:


Pest & Weed Management

spotted knapweedPest management is utilizing environmentally sensitive prevention, avoidance, monitoring and suppression strategies, to manage weeds, insects, diseases, animals and other organisms (including invasive and non-invasive species), that directly or indirectly cause damage or annoyance.


Use of pesticides to control crop pests is the first piece of pest management, although integrated pest management (IPM) is growing more popular. Integrated pest management is a set of strategies based on monitoring, economic thresholds and preventative tactics to determine if and when pest treatment is needed. Integrated pest management is more advanced than using pesticide alone for insect control, especially for fruit and vegetable production.


Groundwater contamination due to pesticide leaching is a concern especially in wellhead protection areas and susceptible soils. River, lake and stream pollution from pesticides in agricultural runoff is also a concern. An IPM approach to pest control can reduce the amount of pesticides applied to cropland, lowering pesticide expenses while protecting water quality.


This practice offers an incentive payment for up to 3 years for the management of invasive species up to 120 acres. Invasive species to be controlled include European and glossy buckthorn, Multiflora Rose, Japanese barberry, honeysuckle, and more.


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Residue Management

Conservation tillage is any tillage practice that leaves additional residue on the soil surface for purposes of erosion control on agricultural fields. Many different variations of this common practice are implemented, the specific variation selected is often based on climatic conditions and available equipment.


Since 1994, the USDA has required the use of conservation measures on highly erodible land to remain eligible for program benefits. Conservation tillage is one of the easiest ways to protect erodible land with the least interruption of cropping practices. Crop residue is the most important factor effecting erosion from different tillage systems. The more residue on the land following tillage, the less erosion from the field. No-till and strip till involve planting directly into crop residue that either hasn’t been tilled at all (no-till) or has been tilled only in narrow strips (strip-till).


Water quality improvements are due primarily to improved erosion control but conservation tillage can also protect water from nutrient and pesticide losses.

 eqip schneider strip till

Residue Management with our office includes no-till, strip-till, and ridge-till. The residue management practice pays landowners an incentive payment for no more than 3 years to leave at least 30% residue on their crop fields. Residue levels are checked by SWCD or NRCS employees in the spring immediately after planting.


Landowners may not sign up to receive their 3 years of incentive payments during the first year to assist with purchasing tillage equipment that has the ability to leave 30% residue on the soil surface.


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Test Plots

yield checkNutrient Management (Ag BMP) Demonstration Plots are used to evaluate management strategies. A small strip of cropland is normally used to evaluate the University of Minnesota's nutrient recommendations against the producer's normal management strategies.


Nutrient management demonstration plots can be planned for anyone needing to perform nutrient management. Up to two soil tests are paid for each set of plots. The soil test is for phosphorus (P), potassium (K), pH, and organic matter. Mid-season leaf samples are collected and analyzed for nutrient content and paid for each plot. Incentive Bonuses of $150 per plot are offered.


Manure testing is paid for through a grant and includes analysis of nitrogen (N), phosphorus (P), and potassium (K). Manure spreader calibrations are offered free of charge.