The field used to represent corn production in Illinois is located in McLean County, although the crop is grown extensively throughout the state. According to the 1997 Census of Agriculture, Illinois is ranked 2nd among the major corn producing states in the U.S. The crop is generally planted the early Spring (April) in the south, early May in the north and harvested beginning in August. Continuous corn is practice is much of the region (approximately 30 percent is continuous), however, rotation with other crops such as soybean, wheat, sorghum, and alfalfa is the dominant practice. Most of the corn is planted for feed grain, but may also be planted for oil, sweetener, and for export. Planting depth and row spacing (generally 30 inches) follows general practices for the U.S. Conservation tillage practices are regularly used for field corn with no-till practiced on about 20 percent of the corn acreage annually. About 50 percent of the acreage is cultivated with a row cultivator and an estimated 40 percent is rotary hoed annually. The crop is rarely grown under irrigation. The soil selected to simulate the field is an Adair clan loam. Adair clay loam is a fine, smectitic, mesic Aquertic Argiudolls. More than 50 percent of the soil is used for the production of grains with the balance in meadow and pasture. Adair clay loam is a deep, somewhat poorly drained, medium to rapid runoff, slowly permeable soil formed on uplands in a thin mantle of loess or loess and pedisediments and a paleosol formed in glacial till. They are on convex summits of narrow interfluves and on convex side slopes at slightly lower elevations. Slopes are generally between 2 to 18 percent, but may range to 30 percent. The soils are extensive in MLRA 108 and found in many MLRA in the region. Adair clay loam is a Hydrologic Group C soil.
|Starting Date||January 1, 1948||Meteorological File - Burlington, IA (W14931)|
|Ending Date||December 31, 1983||Meteorological File - Burlington, IA (W14931)|
|Pan Evaporation Factor (PFAC)||0.77||PRZM Manual Figure 5.1 (EPA, 1998)|
|Snowmelt Factor (SFAC)||0.36 cm C- 1||PRZM Manual Table 5.1 (EPA, 1998)|
|Minimum Depth of Evaporation (ANETD)||16.0 cm||PRZM Manual Figure 5.2 (EPA, 1998)|
|Method to Calculate Erosion (ERFLAG)||4 (MUSS)||PRZM Manual (EPA, 1998)|
|USLE K Factor (USLEK)||0.32 tons EI-1*||GLEAMS Table of Representative Soils (USDA, 1990)|
|USLE LS Factor (USLELS)||1.126||GLEAMS Table of Representative Soils (USDA, 1990)|
|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%||Selected according to QA/QC Guidance (EPA, 2001)|
|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); Lyle Paul of U of Illinois indicates residues are typically chiseled in|
|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 - Burlington, IA (W14931)|
|Maximum rainfall interception storage of crop (CINTCP)||0.25||Maximum recommended value for grass|
|Maximum Active Root Depth (AMXDR)||90 cm||PRZM Input Collator (Burns, 1992)|
|Maximum Canopy Coverage (COVMAX)||100||PRZM Input Collator (Burns, 1992); Lyle Paul of U of Illinois|
|Soil Surface Condition After Harvest (ICNAH)||3||PRZM Input Collator (Burns, 1992); Lyle Paul of U of Illinois|
|Date of Crop Emergence
(EMD, EMM, IYREM)
|01/05||Usual Planting and Harvest Dates for US Field Crops (USDA, 1984) & Updated Crop Stage Information from HED (Bernard Schneider)|
|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)||4 (Top horizon split in two)|
|First, Second, Third and Fourth Soil Horizons (HORIZN = 1,2,3,4)|
|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.
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).