Michael A. Schmitt, Professor, Department of Soil, Water and Climate mschmitt@soils.umn.edu
Gyles W. Randall, Professor, Southern Research and Outreach
Center
Michael P. Russelle, Professor, Department of Soil, Water and
Climate
Craig C. Sheaffer, Professor, Department of Agronomy and Plant
Genetics
Lou J. Greub
Paul D. Clayton
Completed, 1997
Perennial cool-season grasses in a crop rotation provide alternative land area for in-season manure applications. Reed canarygrass might be suitable crop for manure application due to its consistently high yields and nitrogen (N) uptake capacity. The primary objective of this research was to determine the agronomic responses and feasibility of reed canarygrass to in-season manure application rates. Field studies were established at three locations with pure stands of reed canarygrass. Treatments included a series of liquid dairy manure and fertilizer N rates. In addition, broadcast or surface-band manure placement configurations and single or split manure application timings were compared with one manure rate. Manure application rates up to 40 000 gal/acre/yr (approximately 920 lb total N/acre/yr) were applied. A positive dry matter yield response was measured with increasing rates of manure or fertilizer N. Grass stand density generally increased with manure or fertilizer compared to the unfertilized control. With the 20 000 gal/acre rate, split applications with manure applied in early spring resulted in superior yields compared to split manure applications made after the second and third forage cuttings. For the 20 000 gal/acre manure application rate, split application of the manure after the second and third cuttings did not result in significantly greater forage yields than a single application made after the second cutting. Forage yield was similar for broadcast and surface-band manure placement configurations for the one manure rate investigated.
USDA Water Quality Special Grants Program
Michael A. Schmitt, Professor, Department of Soil, Water and Climate mschmitt@soils.umn.edu
Craig C. Sheaffer, Professor, Department of Agronomy and Plant
Genetics
Gyles W. Randall, Professor, Southern Research and Outreach
Center
Completed, 1992
Dairy producers need to consider applying manure onto their alfalfa acres because of environmental concerns regarding overapplication of manure on their corn acres. We compared the use of manure and commercial fertilizer prior to establishment on alfalfa herbage yield and nutrient concentrations. Three rates of manure (3 000, 6 000, and 12 000 gal/acre) were broadcast and incorporated before the direct-seeding of alfalfa. Three commercial fertilizer treatments also were applied to provide P and K application rates similar to those in the manure. At all sites, establishment-year yields from the manure and fertilizer treatments were equal to, or greater (0 - 103%) than, the control yield. With "very high" soil P and K tests, production-year yields were similar for the manure and fertilizer treatments. The responses to fertilizer and manure treatments were similar on the "medium"-testing soil where yields were increased with increasing nutrient rates. Herbage P concentrations were generally not affected by fertilizer or manure additions, while herbage K concentrations were increased in direct proportion to the rate of manure or fertilizer applied at all sites. Preplant manure applications resulted in alfalfa yield increases similar to commercial fertilizer additions where fertilizer would be recommended and was not detrimental to alfalfa production.
Potash and Phosphate Industry-Foundation for Agronomic Research
Michael A. Schmitt, Professor, Department of Soil, Water and Climate mschmitt@soils.umn.edu
Craig C. Sheaffer, Professor, Department of Agronomy and Plant
Genetics
Gyles W. Randall, Professor, Southern Research and Outreach
Center
Completed, 1992
Applying manure to alfalfa poses a potential risk for overloading the soil system with N. The objective of this study was to evaluate the effect of preplant nutrient treatments on alfalfa herbage and crown root N and soil nitrate-N. The effects of three preplant manure rates (3 000, 6 000, and 12 000 gal/acre) and three equivalent P and K fertilizer rates were investigated at Rosemount and Waseca, MN, on a Waukegan silt loam and on a Nicollet clay loam, respectively. Alfalfa herbage N removal was highly correlated to herbage dry matter yield. Herbage N removal in the establishment year was greater for the manure treatments than the P and K fertilizer treatments at the Rosemount sites. The average herbage N removal in the seeding year was 229 lb N/acre for Rosemount-North and in the production year was 278, 341, and 233 lb N/acre for Rosemount-South, Rosemount-North, and Waseca, respectively. Measured soil nitrate-N in plots receiving manure peaked 30 to 50 d after manure application, averaging 328 lb/acre, and decreased throughout the growing season. Peak nitrate-N amounts were proportional to the amount of manure applied. After the second alfalfa growing season, soil nitrate-N amounts were not significantly different among treatments. This study's data indicate that preplant manure applications do not result in consistently more N in the soil or in the plant after 2 yr of alfalfa.
Potash and Phosphate Industry-Foundation for Agronomic Research