OREGON VEGETABLES (Snapbeans)
The field used to represent snapbean production in Oregon is located in Marion County, in the Willamette Valley. According to the 1997 Census of Agriculture, Oregon is ranked 2nd in common bean production in the U.S. behind Wisconsin, and Marion County growers have the largest acreage. Almost all Oregon beans are processed. The crop is generally planted in the late Spring (June) and harvested beginning in August. After the bean plants have flowered, harvest begins approximately 22 days later. Most commercial farms have replaced pole beans with bush beans to facilitate mechanized harvest. Row spacing is generally 36 inches. The crop is mostly grown under irrigation by a variety of overhead sprinkler systems. The soil selected to simulate the field is a benchmark soil, Dayton silt loam. Dayton silt loam, is a fine, smectitic, mesic Vertic, Albaqualfs. The series is used to produce spring grains, grass seed, hay and pasture. A small amount is use for vegetable production. Dayton silt loam is a very deep, poorly drained, very slowly permeable soil with slow runoff or ponded conditions. These soils formed in stratified glacio lacustrine deposits of the Pleistocene age. They are found on nearly level or somewhat concave, slightly depressed parts of broad valley terraces at elevations of 150 to 400 feet above mean sea level on slopes of 0 to 2 percent. The series is extensive in the Willamette Valley. Dayton silt loam is a Hydrologic Group D soil.
|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)||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)||0.43 tons EI-1*||GLEAMS Manual, Table of Representative Soils (USDA, 1990)|
|USLE LS Factor (USLELS)||0.173||GLEAMS Manual, Table of Representative Soils (USDA, 1990)|
|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)||1%||Value set to maximum for crop (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)||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)||0.1||PRZM Manual, Table 5.4 (EPA, 1998)|
|Maximum Active Root Depth (AMXDR)||18 cm||PRZM Input Collator, PIC (Burns, 1992); PRZM Table 5.9 (EPA, 1998)|
|Maximum Canopy Coverage (COVMAX)||80||PRZM Input Collator (Burns, 1992)|
|Soil Surface Condition After Harvest (ICNAH)||1||Set to conservative input assuming field fallow until next crop.|
|Date of Crop Emergence
(EMD, EMM, IYREM)
|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)||92, 89, 90||GLEAMS Table A-3; Close-seeded legumes Fallow = Fallow ST/CT/poor; Cropping and Residue = SR, conventional tillage, poor condition (USDA, 1990)|
|Manning's N Value (MNGN)||0.011||RUSLE Project; A12BGBGC; Bean, Green, conventional tillage, Portland, OR (USDA, 2000)|
|USLE C Factor (USLEC)||0.152 - 0.884||RUSLE Project; A12BGBGC; Bean, Green, conventional tillage, Portland, OR (USDA, 2000)|
|Total Soil Depth (CORED)||100 cm||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)||
||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)|
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).