Cover cropping to reduce nitrate loss through subsurface drainage in the northern U.S. corn belt.

Despite the use of best management practices for nitrogen (N) application rate and timing, significant losses of nitrate nitrogen (NO3(-)-N) in drainage discharge continue to occur from row crop cropping systems. Our objective was to determine whether a autumn-seeded winter rye (Secale cereale L.) cover crop following corn (Zea mays L.) would reduce NO3(-)-N losses through subsurface tile drainage in a corn-soybean [Glycine mar (L.) Merr.] cropping system in the northern Corn Belt (USA) in a moderately well-drained soil. Both phases of the corn-soybean rotation, with and without the winter rye cover crop following corn, were established in 1998 in a Normania clay loam (fine-loamy, mixed, mesic Aquic Haplustoll) soil at Lamberton, MN. Cover cropping did not affect subsequent soybean yield, but reduced drainage discharge, flow-weighted mean nitrate concentration (FWMNC), and NO3(-)-N loss relative to winter fallow, although the magnitude of the effect varied considerably with annual precipitation. Three-year average drainage discharge was lower with a winter rye cover crop than without (p = 0.06). Over three years, subsurface tile-drainage discharge was reduced 11% and NO3(-)-N loss was reduced 13% for a corn-soybean cropping system with a rye cover crop following corn than with no rye cover crop. We estimate that establishment of a winter rye cover crop after corn will be successful in one of four years in southwestern Minnesota. Cover cropping with rye has the potential to be an effective management tool for reducing NO3(-)-N loss from subsurface drainage discharge despite challenges to establishment and spring growth in the north-central USA.

[1]  Noah N. Ranells,et al.  Winter annual grass-legume bicultures for efficient nitrogen management in no-till corn , 1997 .

[2]  M. B. David,et al.  Anthropogenic inputs of nitrogen and phosphorus and riverine export for Illinois, USA. , 2000 .

[3]  C. M. Cooper,et al.  Biological Effects of Agriculturally Derived Surface Water Pollutants on Aquatic Systems—A Review , 1993 .

[4]  Modeling Nitrate Nitrogen Leaching in Response to Nitrogen Fertilizer Rate and Tile Drain Depth or Spacing for Southern Minnesota, USA , 2000 .

[5]  A. M. Decker,et al.  Conserving Residual Corn Fertilizer Nitrogen with Winter Cover Crops , 1992 .

[6]  G W Randall,et al.  Nitrate losses in subsurface drainage from a corn-soybean rotation as affected by time of nitrogen application and use of nitrapyrin. , 2003, Journal of environmental quality.

[7]  W. W. Nelson,et al.  Nitrate Accumulation in Soils and Loss in Tile Drainage Following Nitrogen Applications to Continuous Corn , 1978 .

[8]  Robert L. Hill,et al.  Soil nitrate concentrations under corn as affected by tillage, manure, and fertilizer applications , 1993 .

[9]  E. J. Monke,et al.  Pesticide and Nutrient Movement into Subsurface Tile Drains on a Silt Loam Soil in Indiana , 1991 .

[10]  J. Meisinger,et al.  Kill Date of Vetch, Rye, and a Vetch–Rye Mixture: I. Cover Crop and Corn Nitrogen , 1997 .

[11]  K. Staver,et al.  Using cereal grain winter cover crops to reduce groundwater nitrate contamination in the mid-Atlantic coastal plain , 1998 .

[12]  D. J. Eckert.  Rye cover crops for no-tillage corn and soybean production , 1988 .

[13]  K. Staver,et al.  Patterns of soil nitrate availability in corn production systems: implications for reducing groundwater contamination , 1990 .

[14]  D. Walters,et al.  Winter rye as a cover crop following soybean under conservation tillage , 1997 .

[15]  W. W. Nelson,et al.  Nitrate losses through subsurface tile drainage in Conservation Reserve Program, alfalfa, and row crop systems , 1997 .

[16]  U. Sainju,et al.  Winter cover cropping influence on nitrogen in soil , 1997 .

[17]  David A. Kovacic,et al.  Nitrogen Balance in and Export from an Agricultural Watershed , 1997 .

[18]  R. L. Blevins,et al.  Nitrate Leaching as Influenced by Cover Cropping and Nitrogen Source , 1994 .

[19]  W. Wiseman,et al.  Hypoxia in the Gulf of Mexico. , 2001, Journal of environmental quality.

[20]  Jerry L. Hatfield,et al.  Surface energy balance partitioning over rye and oats cover crops in central Iowa , 1998 .

[21]  Noah N. Ranells,et al.  Nitrogen Release from Grass and Legume Cover Crop Monocultures and Bicultures , 1996 .

[22]  J. L. Baker,et al.  Nitrate-Nitrogen in Tile Drainage as Affected by Fertilization 1 , 1981 .

[23]  R. C. Moore,et al.  Transport of agrichemicals to ground and surface water in a small central indiana watershed , 1998 .

[24]  M. Alley,et al.  Effectiveness of winter rye for accumulating residual fertilizer N following corn , 1993 .