The field used to represent corn production in Ohio is located in Darke and/or Pickaway Counties, although the crop is grown extensively throughout the state. According to the 1997 Census of Agriculture, Ohio is ranked 6th among the major corn producing states in the U.S. and Darke and Pickaway are ranked among the highest in Ohio. The crop is generally planted in early Spring (April 15 to May 10) in the north and from April 10 to May 10 in the south. Corn is harvested beginning in September depending on kernel moisture and may extend into late November. Continuous corn is practice in the region (approximately 30 percent is continuous), however, rotation with mainly soybean is the most common. Rotation promotes weed control and has been shown to increase yields as much as 10 percent over continuous corn operations. Most of the corn is planted for feed grain, but may also be planted for oil, sweetener, and for export. Planting depth (1 - 1.5 inches) and row spacing (generally 30 inches, but may be as narrow as 15 to 22 inches) follows general practices for the U.S. Seeding rates in Ohio range from 20,000 to 30,000 plants/acre for corn grown for grain and 22,000 to 34,000 plants/acre for corn grown for silage. Conservation tillage practices are regularly used for field corn with no-till practiced on a small percentage of the corn acreage annually. Corn is generally cultivated with a row cultivator or rotary hoed. The crop is rarely grown under irrigation. The soil selected to simulate the field is a Cardington silt loam. Cardington silt loam is a fine, illitic, mesic Aquic Haplaudalfs. Most of the area is planted in row crops including production of grains with the balance in pasture and woodland. Cardington silt loam is a very deep, moderately well drained, negligible to very high runoff, slowly permeable soil with an intermittent perched water table at 1-2 feet between November and April. These soils formed in loamy till of medium calcium carbonate content. These soils are on summits, shoulders, and backslopes on Wisconsin Age ground moraines and end moraines. Slopes are generally between 0 to 25 percent. The soils are extensive in MLRA 111 and 139. Cardington silt loam is a Hydrologic Group C soil.
|Starting Date||January 1, 1948||Meteorological File - Vandalia, OH (W93815)|
|Ending Date||December 31, 1983||Meteorological File - Vandalia, OH (W93815)|
|Pan Evaporation Factor (PFAC)||0.77||PRZM Manual Figure 5.1 (EPA, 1998)|
|Snowmelt Factor (SFAC)||0.30 cm C- 1||PRZM Manual Table 5.1 (EPA, 1998)|
|Minimum Depth of Evaporation (ANETD)||17.0 cm||PRZM Manual Figure 5.2 (EPA, 1998)|
|Method to Calculate Erosion (ERFLAG)||4 (MUSS)||PRZM Manual (EPA, 1998)|
|USLE K Factor (USLEK)||0.37 tons EI-1*||PIC; verified w/ FARM Manual Table 3.1|
|USLE LS Factor (USLELS)||1.57||Haan and Barfield, 1979|
|USLE P Factor (USLEP)||1.00||PRZM Manual (EPA, 1998)|
|Field Area (AFIELD)||172 ha||Area of Shipman Reservoir watershed (EPA, 1999)|
|NRCS Hyetograph (IREG)||3||PRZM Manual Figure 5.12 (EPA, 1998)|
|Slope (SLP)||6%||Set to maximum according to guidance. Series range: up 25%; http://soils.usda.gov/technical/classification/osd/index.html|
|Hydraulic Length (HL)||600 m||Shipman Reservoir (EPA, 1999)|
* EI = 100 ft-tons * in/ acre*hr
|Initial Crop (INICRP)||1||Set to one for all crops (EPA, 2001)|
|Initial Surface Condition (ISCOND)||3||PRZM Input Collator (Burns, 1992);|
|Number of Different Crops (NDC)||1||Set to crops in simulation - generally one|
|Number of Cropping Periods (NCPDS)||36||Set to weather data. Meteorological File - Vandalia, OH (W93815)|
|Maximum rainfall interception storage of crop (CINTCP)||0.25||PIC (confirmed using Table 5.4 from PRZM Manual)|
|Maximum Active Root Depth (AMXDR)||100 cm||http://www.wacd.org/ set to soil profile depth|
|Maximum Canopy Coverage (COVMAX)||100||Set to default according to guidance; Consistent with information from: Lyle Paul of U of Illinois|
|Soil Surface Condition After Harvest (ICNAH)||3||PIC (Lyle Paul of U of Illinois indicates residues are typically chiseled in, practice similar in Ohio)|
|Date of Crop Emergence
(EMD, EMM, IYREM)
|01/05||Usual Planting and Harvest Dates for US Field Crops (USDA, 1984)|
|Date of Crop Maturity
(MAD, MAM, IYRMAT)
|Date of Crop Harvest
(HAD, HAM, IYRHAR)
|Maximum Dry Weight (WFMAX)||0.0||Set to "0" Not used in simulation|
|SCS Curve Number (CN)||91, 87, 88||Gleams Manual Table A.3, Fallow = SR/poor; Cropping and Residue = Row Crop, SR/poor condition (USDA, 1990)|
|Manning's N Value (MNGN)||0.014||RUSLE Project, MA3CGSBC; Corn, grain, Conventional tillage, Springfield, IL (USDA, 2000)|
|USLE C Factor (USLEC)||0.017 - 0.638||RUSLE Project; MA3CGSBC; Corn, grain, Conventional tillage, Springfield, IL, variable with date (USDA, 2000)|
|Total Soil Depth (CORED)||100 cm||PIC (Burns, 1992) Confirmed with: NRCS, National Soils Characterization Database (NRCS, 2001)|
|Number of Horizons (NHORIZ)||3 (Top horizon split in two)|
|First, Second, and Third Soil Horizons (HORIZN = 1,2,3)|
|Horizon Thickness (THKNS)||
||PIC (Burns, 1992) Confirmed with: NRCS, National Soils Characterization Database (NRCS, 2001) http://soils.usda.gov/survey/nscd/|
|Bulk Density (BD)||
|Initial Water Content (THETO)||
|Compartment Thickness (DPN)||
|Field Capacity (THEFC)||
|Wilting Point (THEWP)||
|Organic Carbon Content (OC)|
Burns. 1992. Burns, L.A., (Coordinator), B.W. Allen, Jr., M.C. Barber, S.L. Bird, J.M. Cheplick, M.J. Fendley, D.R. Hartel, C.A. Kittner, F.L. Mayer, Jr., L.A. Suarez, and S.E. Wooten. Pesticide and Industrial Chemical Risk Analysis and Hazard Assessment, Version 3.0. (PIRANHA) Environmental Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Athens, GA. 1992.
EPA. 1998. Carsel, R.F., J.C. Imhoff, P.R. Hummel, J.M. Cheplick, and A.S. Donigian, Jr. PRZM-3, A Model for Predicting Pesticide and Nitrogen Fate in the Crop Root and Unsaturated Soil Zones: Users Manual for Release 3.0. National Exposure Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Athens, GA.
EPA. 1999. Jones, R.D., J. Breithaupt, J. Carleton, L. Libelo, J. Lin, R. Matzner, and R. Parker. Guidance for Use of the Index Reservoir in Drinking Water Exposure Assessments. Environmental Fate and Effects Division, Office of Pesticide Programs, U.S. Environmental Protection Agency, Washington. D.C.
EPA. 2001. Abel, S.A. Procedure for Conducting Quality Assurance and Quality Control of Existing and New PRZM Field and Orchard Crop Standard Scenarios. Environmental Fate and Effects Division, Office of Pesticide Programs, U.S. Environmental Protection Agency, Washington, D.C.
Haan, C.T. and B.J. Barfield. 1978. Hydrology and Sedimentology of Surface Mined Lands. Office of Continuing Education and Extension, College of Engineering, University of Kentucky, Lexington, Kentucky 40506. pp. 286.
USDA. 1984. Usual Planting and Harvesting Dates for U.S. Field Crops, Statistical Reporting Service, U.S. Department of Agriculture, Agriculture Handbook #628, pp.78.
USDA. 1990. Davis, F.M., R.A. Leonard, W.G. Knisel. GLEAMS User Manual, Version 1.8.55. USDA-ARS Southeast Watershed Research Laboratory, Tifton GA. SEWRL-030190FMD.
USDA. 2000. Revised Universal Soil Loss Equation (RUSLE) EPA Pesticide Project. U.S. Department of Agriculture, National Resources Conservation Service (NRCS) and Agricultural Research Service (ARS).