PE4.01 (SUPERSEDED) MetaData - CALIFORNIA ALMOND/WALNUTS (Northern and Southern)

MetaData

The field used to represent almond production in California is located in San Joaquin County in the Central Valley, although almonds production areas are well distributed throughout the Central and Sacramento Valleys. According to the 1997 Census of Agriculture, California is the major producer of almonds and walnuts in the U.S.. Almonds are generally grown on low terraces. All types of irrigation is used. The floor of almond groves are kept smooth and clear to facilitate collection of the nuts after harvesting which is accomplished by shaking the trees. The soil selected to simulate the field is a Manteca fine sandy loam. Manteca fine sandy loam is a coarse-loamy, mixed, thermic Haplic Durixerolls. These soils are often used for a variety of crops including Almonds. Manteca fine sandy loam consists of moderately deep, moderately well drained, slow runoff, moderately permeable above the hardpan soil that formed in alluvium mainly from mixed rock sources. These soil are generally found on low terraces at elevations of 20 to 110 feet above mean sea level and have slopes of 0 to 2 percent. The soil is of small extent in MLRA17. Manteca fine sandy loam is a Hydrologic Group C soil.

Table 1
PRZM 3.12 Climate and Time Parameters for San Joaquin County, California - Almonds
Parameter	Value	Source
Starting Date	January 1, 1948	Meteorological File - Southern: Bakersfield, CA (W23155) or Northern: Sacramento, CA (W23232)
Ending Date	December 31, 1983	Meteorological File - Southern: Bakersfield, CA (W23155)or Northern: Sacramento, CA (W23232)
Pan Evaporation Factor (PFAC)	0.7	PRZM Manual Figure 5.1 (EPA, 1998)
Snowmelt Factor (SFAC)	0.55 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)

Table 2
PRZM 3.12 Erosion and Landscape Parameters for San Joaquin County, California - Almonds
Parameter	Value	Source
Method to Calculate Erosion (ERFLAG)	4 (MUSS)	PRZM Manual (EPA, 1998)
USLE K Factor (USLEK)	0.28 tons EI^-1*	NRI - Average value listed for the soil series Manteca
USLE LS Factor (USLELS)	0.2	NRI - Average value listed for the soil series Manteca
USLE P Factor (USLEP)	1.0	NRI - Average value listed for the soil series Manteca
Field Area (AFIELD)	172 ha	Area of Shipman Reservoir watershed (EPA, 1999)
NRCS Hyetograph (IREG)	1	PRZM Manual Figure 5.12 (EPA, 1998)
Slope (SLP)	2 %	Paul Verdegaal San Joaquin County Cooperative Extension 209-468-9494
Hydraulic Length (HL)	600 m	Shipman Reservoir (EPA, 1999)
Irrigation Flag (IRFLAG)	2 (cropping period only)	Based on recommendations from farm advisors for general flooding for crop irrigation
Irrigation Type (IRTYP)	1 (Flood)	Based on recommendations from farm advisors for general flooding for crop irrigation
Leaching Factor (FLEACH)	0.1	Estimated
Fraction of Water Capacity when Irrigation is Applied (PCDEPL)	0.55	Based on recommendations from farm advisors for general flooding for crop irrigation
Maximum Rate at which Irrigation is Applied (RATEAP)	0.4 cm hr^-1	PRZM Manual, Table 5.33 (EPA, 1998)

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

Table 3
PRZM 3.12 Crop Parameters for San Joaquin County, California - Almonds
Parameter	Value	Source
Initial Crop (INICRP)	1	Set to one for all crops (EPA, 2001)
Initial Surface Condition (ISCOND)	3	Paul Verdegaal San Joaquin County Cooperative Extension 209-468-9494
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 - Bakersfield, CA (W23155) or Sacramento, CA (W23232)
Maximum rainfall interception storage of crop (CINTCP)	0.25	PIC; confirmed using Table 5.4 from PRZM Manual (Burns, 1992 and EPA, 1985)
Maximum Active Root Depth (AMXDR)	120	Paul Verdegaal San Joaquin County Cooperative Extension 209-468-9494
Maximum Canopy Coverage (COVMAX)	90	Paul Verdegaal San Joaquin County Cooperative Extension 209-468-9494
Soil Surface Condition After Harvest (ICNAH)	2	Paul Verdegaal San Joaquin County Cooperative Extension 209-468-9494
Date of Crop Emergence (EMD, EMM, IYREM)	18/01	Values complied by HED for Almonds
Date of Crop Maturity (MAD, MAM, IYRMAT)	02/08	Values complied by HED for Almonds
Date of Crop Harvest (HAD, HAM, IYRHAR)	13/09	Values complied by HED for Almonds
Maximum Dry Weight (WFMAX)	0.0	Set to "0" Not used in simulation
SCS Curve Number (CN)	84, 79, 82	Gleams Manual Table A.3, Meadow
Manning's N Value (MNGN)	0.023	RUSLE Project; C21OCOCM for orchards, cov alley in Sacramento (USDA, 2000)
USLE C Factor (USLEC)	0.34 - 0.221	RUSLE Project; C21OCOCM for orchards, cov alley in Sacramento (USDA, 2000)

Table 4
PRZM 3.12 Manteca Soil Parameters for San Joaquin County, California - Almonds
Parameter	Value	Verification Source
Total Soil Depth (CORED)	317 cm	NRCS, National Soils Characterization Database (NRCS, 2001)
Number of Horizons (NHORIZ)	3 (Top horizon split in two)	NRCS, National Soils Characterization Database (NRCS, 2001)
	First, Second, and Third Soil Horizons (HORIZN = 1,2,3)
Horizon Thickness (THKNS)	10 cm (HORIZN = 1) 7 cm (HORIZN = 2) 300 cm (HORIZN = 3)	NRCS, National Soils Characterization Database (NRCS, 2001) http://www.nrcs.usda.gov/wps/portal/nrcs/site/soils/home/ Ed Russell (USDA-NRCS, Fresno)
Bulk Density (BD)	1.55 g cm^-3 (HORIZN = 1,2) 1.6 g cm^-3 (HORIZN = 3)
Initial Water Content (THETO)	0.22 cm³-H₂O cm³-soil (HORIZN =1,2) 0.23 cm³-H₂O cm³-soil (HORIZN =3)
Compartment Thickness (DPN)	0.1 cm (HORIZN = 1) 3.5 cm (HORIZN =2) 30 cm (HORIZN = 3)
Field Capacity (THEFC)	0.22 cm³-H₂O cm³-soil (HORIZN = 1,2) 0.23 cm³-H₂O cm³-soil (HORIZN = 3)
Wilting Point (THEWP)	0.1 cm³-H₂O cm³-soil (HORIZN = 1,2) 0.23 cm³-H₂O cm³-soil (HORIZN = 3)
Organic Carbon Content (OC)	0.81% (HORIZN = 1,2) 0.18% (HORIZN = 3)

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. 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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