PE4.01 (SUPERSEDED) MetaData - OREGON SWEET CORN

MetaData

The field used to represent sweet corn production in Oregon is located in Marion County, in the Willamette Valley. According to the 1997 Census of Agriculture, Oregon is ranked 4th in sweet corn for processing. Only a small percent is produced for the fresh market. Marion County farmers harvest the most acres in the state. The crop is generally planted in the early Spring (May) and harvested beginning in September. Continuous sweet corn is practice is much of the region, however, rotation with other crops is practiced as well. Planting depth and row spacing (generally 30 inches) follows general practices for the U.S. Conventional tillage dominates, followed by conservation tillage and no-tillage. The crop is rarely grown under irrigation. The soil selected to simulate the field is a benchmark soil, Woodburn silt loam. Woodburn silt loam, is a fine-silty mixed, superactive, mesic Aquultic Agrixerolls. The series is used to produce berries, orchards, cannery crops, grain, hay, and pasture. Woodburn silt loam is a very deep, moderately well drained, slowly permeable soil with slow to medium runoff. These soils formed in stratified glacio lacustrine deposits of the Pleistocene age. They are found on nearly level to gently sloping broad valley terraces at elevations of 150 to 400 feet above mean sea level on slopes of 0 to 55 percent. The series is extensive in the Willamette Valley. Woodburn silt loam is a Hydrologic Group C soil.

Table 1.
PRZM 3.12 Climate and Time Parameters for Marion County Oregon - Sweet Corn
Parameter Value Source
Starting Date January 1, 1948 Meteorological File - Salem, OR (W24232)
Ending Date December 31, 1983 Meteorological File - Salem, OR (W24232)
Pan Evaporation Factor (PFAC) 0.74 PRZM Manual Figure 5.1 (EPA, 1998)
Snowmelt Factor (SFAC) 0.15 cm C- 1 PRZM Manual Table 5.1 (EPA, 1998)
Minimum Depth of Evaporation (ANETD) 15.0 cm PRZM Manual Figure 5.2 (EPA, 1998)
Table 2.
PRZM 3.12 Erosion and Landscape Parameters for Marion County Oregon - Sweet Corn
Parameter Value Source
Method to Calculate Erosion (ERFLAG) 4 (MUSS) PRZM Manual (EPA, 1998)
USLE K Factor (USLEK) 0.33 tons EI-1* Farm Manual, Table 3.1 (EPA, 1985)
USLE LS Factor (USLELS) 1.34 Haan and Barfield, 1978
USLE P Factor (USLEP) 1.0 Set according to guidance (EPA, 2001)
Field Area (AFIELD) 172 ha Area of Shipman Reservoir watershed (EPA, 1999)
NRCS Hyetograph (IREG) 2 PRZM Manual Figure 5.12 (EPA, 1998)
Slope (SLP) 6% Value set to maximum for crop (EPA, 2001)
Hydraulic Length (HL) 600 m Shipman Reservoir (EPA, 1999)

* EI = 100 ft-tons * in/ acre*hr

Table 3.
PRZM 3.12 Crop Parameters for Marion County, Oregon - Sweet Corn
Parameter Value Source
Initial Crop (INICRP) 1 Set to one for all crops (EPA, 2001)
Initial Surface Condition (ISCOND) 1 Set to residue prior to new crop planting
Number of Different Crops (NDC) 1 Set to crops in simulation - generally one
Number of Cropping Periods (NCPDS) 36 Set to weather data. Salem, OR (W24232)
Maximum rainfall interception storage of crop (CINTCP) 0.25 PRZM Manual, Table 5.4 (EPA, 1998)
Maximum Active Root Depth (AMXDR) 90 cm PRZM Input Collator, PIC (Burns, 1992); PRZM Table 5.9 (EPA, 1998)
Maximum Canopy Coverage (COVMAX) 100 Set to default for row crops (EPA, 2001)
Soil Surface Condition After Harvest (ICNAH) 1 Crop profile says some are moving to cover crops, grass, instead of wheat- most conservative scenario chosen
Date of Crop Emergence
(EMD, EMM, IYREM)		 10/05 Dan McGrath, OSU extension agent
Date of Crop Maturity
(MAD, MAM, IYRMAT)		 21/08
Date of Crop Harvest
(HAD, HAM, IYRHAR)		 10/09
Maximum Dry Weight (WFMAX) 0.0 Set to "0" Not used in simulation
SCS Curve Number (CN) 91, 85, 87 Gleams Manual Table A.3,SR/fallow and SR/Row crops from table H-4 (USDA, 1990)
Manning's N Value (MNGN) 0.014 RUSLE Project, A13CSWWC, Corn, Silage, Conventional Tillage, Salem, OR (USDA, 2000)
USLE C Factor (USLEC) 0.099 - 0.528 RUSLE Project; A13CSWWC, Corn, Silage, Conventional Tillage, Salem, OR (USDA, 2000)
Table 4.
PRZM 3.12 Woodburn Soil Parameters for Marion County, Oregon - Sweet Corn
Parameter Value Verification Source
Total Soil Depth (CORED) 203 cm NRCS, National Soils Characterization Database (NRCS, 2001)
Number of Horizons (NHORIZ) 7 (Top horizon split in two)
  First, Second, Third, Fourth, Fifth, Sixth, and Seventh Soil Horizons (HORIZN = 1,2,3,4,5,6,7)  
Horizon Thickness (THKNS)
  • 10 cm (HORIZN = 1)
  • 13 cm (HORIZN = 2)
  • 20 cm (HORIZN = 3)
  • 40 cm (HORIZN = 4,6)
  • 50 cm (HORIZN = 2)
  • 30 cm (HORIZN = 7)
 NRCS, National Soils Characterization Database (NRCS, 2001) http://www.nrcs.usda.gov/wps/portal/nrcs/site/soils/home/
Bulk Density (BD)
  • 1.44 g cm-3 (HORIZN = 1,2,5)
  • 1.53 g cm-3 (HORIZN = 3)
  • 1.45 g cm-3 (HORIZN = 4)
  • 1.37 g cm-3 (HORIZN = 6,7)
Initial Water Content (THETO)
  • 0.301 cm3-H2O cm3-soil (HORIZN =1,2)
  • 0.350 cm3-H2O cm3-soil (HORIZN =3)
  • 0.388 cm3-H2O cm3-soil (HORIZN =4)
  • 0.394 cm3-H2O cm3-soil (HORIZN =5)
  • 0.418 cm3-H2O cm3-soil (HORIZN =6)
  • 0.404 cm3-H2O cm3-soil (HORIZN =7)
Compartment Thickness (DPN)
  • 0.1 cm (HORIZN = 1)
  • 1.0 cm (HORIZN = 2)
  • 2.0 cm (HORIZN = 3,4)
  • 5.0 cm (HORIZN = 5,6)
  • 10.0 cm (HORIZN = 7)
Field Capacity (THEFC)
  • 0.301 cm3-H2O cm3-soil (HORIZN =1,2)
  • 0.350 cm3-H2O cm3-soil (HORIZN =3)
  • 0.388 cm3-H2O cm3-soil (HORIZN =4)
  • 0.394 cm3-H2O cm3-soil (HORIZN =5)
  • 0.418 cm3-H2O cm3-soil (HORIZN =6)
  • 0.404 cm3-H2O cm3-soil (HORIZN =7)
Wilting Point (THEWP)
  • 0.134 cm3-H2O cm3-soil (HORIZN = 1,2)
  • 0.153 cm3-H2O cm3-soil (HORIZN = 3)
  • 0.177 cm3-H2O cm3-soil (HORIZN = 4)
  • 0.185 cm3-H2O cm3-soil (HORIZN = 5)
  • 0.173 cm3-H2O cm3-soil (HORIZN = 6)
  • 0.156 cm3-H2O cm3-soil (HORIZN = 7)
Organic Carbon Content (OC)
  • 1.86% (HORIZN = 1,2)
  • 0.56% (HORIZN = 3)
  • 0.3% (HORIZN = 4)
  • 0.112% (HORIZN = 5)
  • 0.07% (HORIZN = 6)
  • 0.06% (HORIZN = 7)

EPA. 1985. Field Agricultural Runoff Monitoring (FARM) Manual, (EPA/600/3-85/043) Environmental Research Laboratory, U.S. Environmental Protection Agency, Athens, GA.

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. 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).

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