Integrating Cropping and Nutrient Management Systems on Grass-Based Dairies with Manure Slurry Enriched Micro-Site Seeding

Project Overview

Project Type: Research and Education
Funds awarded in 2004: $137,849.00
Projected End Date: 12/31/2009
Region: North Central
State: Michigan
Project Coordinator:
Timothy Harrigan
Biosystems and Agricultural Engineering

Annual Reports


  • Agronomic: grass (misc. perennial), hay
  • Animal Products: dairy


  • Animal Production: manure management, pasture fertility, pasture renovation, grazing - rotational, stockpiled forages, feed/forage
  • Crop Production: continuous cropping, no-till, nutrient cycling
  • Education and Training: demonstration, extension, farmer to farmer, focus group, on-farm/ranch research, participatory research
  • Farm Business Management: budgets/cost and returns
  • Natural Resources/Environment: biodiversity
  • Pest Management: cultural control
  • Production Systems: agroecosystems, integrated crop and livestock systems
  • Soil Management: nutrient mineralization, soil quality/health
  • Sustainable Communities: new business opportunities, sustainability measures


    Manure slurry-enriched seeding is a new manure land application process that combines low-disturbance aeration tillage, manure use and the seeding of forage grasses, legumes and cover crops in one efficient operation. This new seeding method was used to improve dry matter yield and increase botanical diversity in pastures and grass hay fields, and to extend the grazing season by seeding late season grazing crops such as forage turnips and forage rape in wheat stubble. The manure slurry seeding process involved mixing seed in the slurry tank and passing the seed-laden slurry through drop tubes to the fractured and loosened soil behind each set of rolling tines. Red clover and orchard grass were inter-seeded in a mature brome grass stand using swine slurry at a rate to supply about 70 lb nitrogen per acre. The slurry seedings were compared to no-till drilling and frost seeding, with and without a chemical burn-down to suppress competition from the following crop.

    Manure slurry seeding of orchardgrass and red clover was an effective way to expand the land base for manure application, recycle manure nutrients for crop growth, and increase the botanical diversity of pasture and hay ground. No-till drilling and slurry seeding resulted in more uniform stands of red clover and orchardgrass than frost seeding. Compared to the no aeration, no manure control, the no-till, slurry and frost seeded red clover plots increased yields by 105%, 87% and 43%, respectively. Inter-seeding orchard grass in an existing brome grass stand increased the botanical diversity but did not increase dry matter yield. Slurry seeding pastures lead to a yield increase from the added nitrogen but we did not see a clear increase in botanical diversity, presumably because we did not restrict cattle access after seeding to allow an establishment period. Introducing red clover to the brome grass hay improved forage quality by increasing crude protein (CP) and reducing neutral detergent fiber (NDF). The pre-plant burn-down improved the establishment of orchard grass but did not improve the establishment of red clover.
    Forage turnip, forage rape, oats and sorghum-sudan were drilled with 50 lb/ac commercial nitrogen and slurry seeded with swine slurry at a rate to supply 50 lb/ac of readily available N. The dry matter yield of the slurry seeded crops was equal to the drilled crop with 50 lb/ac of commercial N.

    Cattle grazing preference following sub-surface deposition of manure slurry was variable. Where the stocking density was low and they had access to excessive forage they avoided the area where slurry had been applied for three grazing cycles, even after significant rainfall. Where the stocking density was greater the cattle preferentially graze desirable species in the area where slurry had been applied and avoid undesirable species, such as tall fescue, in areas where no manure had been applied.


    In recent years, interest has grown in the use of managed intensive grazing for beef and dairy cattle. Managed intensive grazing can reduce feed and manure handling costs, increase farm profitability, improve animal health, and help reduce manure nutrient loss to the environment. In the Great Lakes region cattle are often on pasture during the growing season and housed during the winter months. Pasture land is often nutrient deficient because crop nutrients are removed in harvested hay early in the growing season when forage supply exceeds grazing demand. Manure nutrients collected throughout the winter can be used to meet the nutrient needs of hay and pasture crops. Manure nutrients are often not well used because the best time for applying manure conflicts with other farming operations such as harvest or planting. A more complete integration of cropping and nutrient management systems on grass-based dairies offers an opportunity to expand the on-farm land base available for manure spreading, minimize manure transport costs, improve on-farm manure nutrient recycling, and improve forage quality and farm profitability.

    Thinning stands are often a problem on a grazing farm, particularly after a dry summer when over grazing occurs. The objective of this project was to develop and evaluate a process whereby forage grass and legume seed was sown in established pasture and hay ground in nutrient rich manure slurry for stand improvement. The seed was mixed with manure slurry in a commercially available tank spreader with by-pass flow from the tank pto-driven pump providing in-tank agitation for seed distribution and uniformity. An AerWay aeration tillage tool with the species-sensitivity distribution (SSD) manure distributor and drop tubes were used to deliver the seed-laden manure slurry to the fractured and loosened ground behind the aeration tines. The overall goal was to develop a process that integrates manure use and nutrient recycling, aeration tillage to alleviate shallow soil compaction, and the seeding of forages and cover crops in one efficient operation.

    Project objectives:

    Grass-based dairy and livestock producers in the Great Lakes region are the intended audience, but the process will benefit producers throughout the North Central states.

    Specific objective of this project are to:
    •Evaluate changes in the species richness and yield of pasture and hay ground from low-disturbance, slurry-enriched seeding of forages and cover crops,
    •Evaluate the effect of slurry seeding on the grazing preference of cattle,
    •Develop guidelines for on-farm pasture and grassland enrichment with slurry seeding,

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.