**Number range CHAPTERCALIFORNIA GARLIC**

[]{.mark}

California is the largest producer of garlic in the United States
measured both in acres and number of producing farms (USDA, 2004).
29,240 acres were dedicated to garlic production in 2001, with 96.5% of
production occurring in Fresno and Kern Counties located within the San
Joaquin Valley. Approximately 65% of California garlic is grown for
dehydration/processing, 20% for fresh market, and 15% (grown in the
Northern and Eastern regions) for seed.

Garlic is propagated vegetatively through the planting of cloves. Root
depth is usually 18-24". Both garlic and onions are grown in elevated
light soil beds planted in double rows at a density of approximately 18
plants per foot. Fields are treated with herbicide immediately after
planting and will usually receive one or two further applications before
harvest. Garlic intended for fresh markets will often go without any
insecticide treatments, while garlic grown for dehydration will receive
insecticide treatments near maturity. The majority of garlic crops,
intended for dehydration, will be mowed up to 2 months before harvest by
mechanical diggers. Garlic grown for fresh markets is harvested earlier
by mechanical "undercut" techniques that loosen the bulbs within the
soil (USDA, 2004)

[]{.mark}

The Met station chosen was the Fresno station (W93193.dvf) located at
36º 47' N, 119º 43' W and at an elevation of approximately 102 meters
above sea level. The station is located within Fresno County where the
majority of garlic is grown and is the closest station containing the
necessary data for PRZM. This station receives an average of
approximately 27 cm of rainfall annually, with the majority of rainfall
occurring between November and March.

[]{.mark}

The Cerini series is the second most common soil found in garlic
producing areas of Fresno, Kern, and Kings Counties, accounting for
nearly 20% of garlic bearing soils acreage (USDA, 2006). Garlic in
California is predominantly grown on clay loam to sandy loam soils (USDA
2004). Cerini soils are found in Fresno and Kings Counties and are
fine-loamy, mixed, superactive, thermic Fluventic Haplocambids soil
found on slopes of 0 to 5% (USDA, 2003). Cerini soils are identified as
garlic bearing soils (USDA 2003, USDA 2006) and are among the top soils
for expected irrigated yields (Table 5). Cerini soils are not expected
to yield garlic without irrigation (USDA, 2006; Table 5). Location and
metfile selections are often the most important developments affecting
scenario vulnerability and protectiveness. Because over 80% of garlic in
California is grown in Fresno County (USDA, 2002; USDA, 2004) the
metfile closest to the center of Fresno county was chosen. In fact,
approximately 95% of garlic grown in Fresno county is grown in the area
bounded by Interstate 5 on the west, the city of Huron on the south, and
US 269 on the east (R. Ehn, California Garlic and Onion Research
Advisory Board, personal communication). This detailed information
allowed for soil selection within that boundary. The Cerini series was
selected for this scenario because it is both representative of garlic
bearing soils, is predominant in the main production area of Fresno
county, and because it represents 60% of soils by drainage, the 90% for
erodibility, and is among the steeper sloped garlic bearing soils (Table
5).

[]{.mark}

[Cerini is a Hydrologic Group C soil, which includes the 90^th^
percentile of these soils in drainage. Cerini soils have a USLE K factor
of 0.37, which is common to 58% of coffee bearing soils and includes the
90^th^ percentile of these soils in erodibility. Approximately 10% of
garlic bearing soils have a pH lower than Cerini soils (7.7). However,
soil pH is not currently a PRZM input parameter and is not expected to
often affect chemical fate in the acidic range. Cerini soils have an A
horizon from 0 to 5 inches (0-13 cm) deep and a B horizon from 5 to 52
inches (13-132 cm) deep. No benchmark soils of California were selected
for this scenario, since no hydrologic group C or D benchmark soils bear
garlic production (USDA, 2006). Cerini clay loam 0-2 percent slopes was
used to parameterize this scenario (USDA 2006).]{.mark}

+-----------------+----------+-----------------------------------------+
| **Table 1. PRZM |          |                                         |
| 3.12 Climate    |          |                                         |
| and Time        |          |                                         |
| Parameters for  |          |                                         |
| Fresno,         |          |                                         |
| California --   |          |                                         |
| Garlic.**       |          |                                         |
+-----------------+----------+-----------------------------------------+
| **Parameter**   | *        | **Source/Comments**                     |
|                 | *Value** |                                         |
+-----------------+----------+-----------------------------------------+
| Starting Date   | Jan. 1,  | Meteorological File from Fresno, CA     |
|                 | 1961     | (W93193)                                |
+-----------------+----------+-----------------------------------------+
| Ending Date     | Dec. 31, | Meteorological File from Fresno, CA     |
|                 | 1990     | (W93193)                                |
+-----------------+----------+-----------------------------------------+
| Pan Evaporation | 0.68     | PRZM Manual Figure 5.1. Value           |
| Factor (PFAC)   |          | represents Southern San Joaquin Valley  |
|                 |          | region.                                 |
+-----------------+----------+-----------------------------------------+
| Snowmelt Factor | 0        | The Weather Channel Interactive, Inc.   |
| (SFAC)          |          | (TWCII, 2006)                           |
+-----------------+----------+-----------------------------------------+
| Minimum Depth   | 17.5 cm  | PRZM Guidance                           |
| of              |          |                                         |
|                 |          |                                         |
| Evaporation     |          |                                         |
| (ANETD)         |          |                                         |
+-----------------+----------+-----------------------------------------+

[]{.mark}

+-----------------+----------+-----------------------------------------+
| **Table 2. PRZM |          |                                         |
| 3.12 Erosion    |          |                                         |
| and Landscape   |          |                                         |
| Parameters for  |          |                                         |
| Fresno,         |          |                                         |
| California --   |          |                                         |
| Garlic.**       |          |                                         |
+=================+==========+=========================================+
| **Parameter**   | *        | **Source/Comments**                     |
|                 | *Value** |                                         |
+-----------------+----------+-----------------------------------------+
| Method to       | 4 (MUSS) | PRZM Manual (EPA, 1998)                 |
| Calculate       |          |                                         |
| Erosion         |          |                                         |
| (ERFLAG)        |          |                                         |
+-----------------+----------+-----------------------------------------+
| USLE K Factor   | 0.37     | USDA NRCS Soil Data Mart                |
| (USLEK)         | tons     | (http://soildatamart.nrcs.usda.gov/)    |
|                 | EI^-1\*^ |                                         |
|                 |          | Value listed for the soil series        |
|                 |          | Cerini.                                 |
+-----------------+----------+-----------------------------------------+
| USLE LS Factor  | 0.15     | PRZM Manual (EPA, 1998)                 |
| (USLELS)        |          |                                         |
|                 |          | LS value for 0.5% slope and 400' slope  |
|                 |          | length; LS equation (Haan and Barfield, |
|                 |          | 1978)                                   |
+-----------------+----------+-----------------------------------------+
| USLE P Factor   | 1.0      | R. Ehn, California Garlic and Onion     |
| (USLEP)         |          | Research Advisory Board                 |
|                 |          |                                         |
|                 |          | Default for crops with no contour       |
|                 |          | practices                               |
+-----------------+----------+-----------------------------------------+
| Field Area      | 172 ha   | Area of Shipman Reservoir watershed     |
| (AFIELD)        |          | (EPA, 1999)                             |
+-----------------+----------+-----------------------------------------+
| NRCS Hyetograph | 1        | PRZM Manual Figure 5.12 (EPA, 1998)     |
| (IREG)          |          |                                         |
+-----------------+----------+-----------------------------------------+
| Slope (SLP)     | 0.5%     | R. Ehn, California Garlic and Onion     |
|                 |          | Research Advisory Board                 |
+-----------------+----------+-----------------------------------------+
| Hydraulic       | 600 m    | Shipman Reservoir (EPA, 1999)           |
| Length (HL)     |          |                                         |
+-----------------+----------+-----------------------------------------+
| Irrigation Flag | 2        | Irrigation is applied during growing    |
| (IRFLAG)        |          | season only. Irrigation of garlic       |
|                 |          | fields is stopped a few weeks prior to  |
|                 |          | harvest to allow the plants to dry.     |
|                 |          | "Water cutoff" normally occurs in early |
|                 |          | June for fresh market fields, and mid   |
|                 |          | June for the fields growing garlic for  |
|                 |          | dehydration (USDA, 2004). 1= growing    |
|                 |          | season only as per PRZM Irrigation      |
|                 |          | Guidance (EPA, 2005)                    |
+-----------------+----------+-----------------------------------------+
| Number range    | 3        | Primarily sprinkler with some drip      |
| CH              | (sp      | (\~15%). Shannon Mueller Farm Advisor,  |
| APTERIrrigation | rinkler) | University of California Cooperative    |
| Type (IRTYP)    |          | Extension; and Irrigation Guidance for  |
|                 |          | developing PRZM Scenarios, Table 3;     |
|                 |          | (EPA 2005).                             |
+-----------------+----------+-----------------------------------------+
| Leaching Factor | 0.1      | Information unavailable, set to default |
| (FLEACH)        |          | = 0.1. Irrigation Guidance for          |
|                 |          | developing PRZM Scenarios, Table 3;     |
|                 |          | (June 15, 2005).                        |
+-----------------+----------+-----------------------------------------+
| Fraction of     | 0.66     | Garlic is generally irrigated at 66%    |
| Water Capacity  |          | AWC. Shannon Mueller, Farm Advisor,     |
| when Irrigation |          | University of California Cooperative    |
| is Applied      |          | Extension; and Irrigation Guidance for  |
| (PCDEPL)        |          | developing PRZM Scenarios, Table 3;     |
|                 |          | (EPA 2005).                             |
+-----------------+----------+-----------------------------------------+
| Maximum Rate at | 0.068 cm | Irrigation Guidance for developing PRZM |
| which           | hr^-1^   | Scenarios, Table 1; (June 15, 2005).    |
| Irrigation is   |          | For CN = 87 and f = 0.1                 |
| Applied         |          |                                         |
| (RATEAP)        |          |                                         |
+-----------------+----------+-----------------------------------------+
| \* EI = 100     |          |                                         |
| ft-tons \* in/  |          |                                         |
| acre\*hr        |          |                                         |
+-----------------+----------+-----------------------------------------+
| []{.mark}       |          |                                         |
+-----------------+----------+-----------------------------------------+

[]{.mark}

+-----------------+----------+-----------------------------------------+
| **Table 3. PRZM |          |                                         |
| 3.12 Crop       |          |                                         |
| Parameters for  |          |                                         |
| Fresno,         |          |                                         |
| California --   |          |                                         |
| Garlic.**       |          |                                         |
+=================+==========+=========================================+
| **Parameter**   | *        | **Source/Comments**                     |
|                 | *Value** |                                         |
+-----------------+----------+-----------------------------------------+
| Initial Crop    | 1        | Set to one for all crops (EPA, 2004).   |
| (INICRP)        |          |                                         |
+-----------------+----------+-----------------------------------------+
| Initial Surface | 1        | R. Ehn, California Garlic and Onion     |
| Condition       |          | Research Advisory Board. Garlic         |
|                 |          | requires a well prepared soil surface.  |
| (ISCOND)        |          |                                         |
+-----------------+----------+-----------------------------------------+
| Number of       | 1        | Set to number of crops in simulation.   |
| Different Crops |          |                                         |
| (NDC)           |          |                                         |
+-----------------+----------+-----------------------------------------+
| Number of       | 30       | Set to weather data in meteorological   |
| Cropping        |          | file: Fresno, CA (W93193).              |
| Periods (NCPDS) |          |                                         |
+-----------------+----------+-----------------------------------------+
| Maximum         | 0.1      | Recommended value for light density     |
| rainfall        |          | crops (EPA, 2004).                      |
| interception    |          |                                         |
| storage of crop |          |                                         |
| (CINTCP)        |          |                                         |
+-----------------+----------+-----------------------------------------+
| Maximum Active  | 46 cm    | R. Ehn, California Garlic and Onion     |
| Root Depth      |          | Research Advisory Board.                |
| (AMXDR)         |          |                                         |
+-----------------+----------+-----------------------------------------+
| Maximum Canopy  | 80       | R. Ehn, California Garlic and Onion     |
| Coverage        |          | Research Advisory Board. Gaps in        |
| (COVMAX)        |          | coverage between rows.                  |
+-----------------+----------+-----------------------------------------+
| Soil Surface    | 2        | R. Ehn, California Garlic and Onion     |
| Condition After |          | Research Advisory Board. Leaf material  |
| Harvest (ICNAH) |          | left in soil after bulb removal.        |
+-----------------+----------+-----------------------------------------+
| Date of Crop    | 30/10/60 | R. Ehn, California Garlic and Onion     |
| Emergence       |          | Research Advisory Board. Planting       |
|                 |          | proceeds early September. Emergence set |
| (EMD, EMM,      |          | to previous year to ensure mature plant |
| IYREM)          |          | during the initial year of simulation.  |
+-----------------+----------+-----------------------------------------+
| Date of Crop    | 15/05/61 | R. Ehn, California Garlic and Onion     |
| Maturity        |          | Research Advisory Board.                |
|                 |          |                                         |
| (MAD, MAM,      |          |                                         |
| IYRMAT)         |          |                                         |
+-----------------+----------+-----------------------------------------+
| Date of Crop    | 30/07/61 | R. Ehn, California Garlic and Onion     |
| Harvest (HAD,   |          | Research Advisory Board.                |
| HAM, IYRHAR)    |          |                                         |
|                 |          | Harvest begins late July and can        |
|                 |          | proceed into October.                   |
+-----------------+----------+-----------------------------------------+
| Maximum Dry     | 0.0      | Not used in scenario                    |
| Weight (WFMAX)  |          |                                         |
+-----------------+----------+-----------------------------------------+
| Maximum Height  | 18"      | R. Ehn, California Garlic and Onion     |
| (HFMAX)         |          | Research Advisory Board.                |
+-----------------+----------+-----------------------------------------+
| SCS Curve       | 91, 87,  | Gleams Manual Table H-4; (1)fallow,     |
| Number (CN)     | 88       | straight row; cropping and residue =    |
|                 |          | row crop, straight row, poor, C (USDA,  |
|                 |          | 1990)                                   |
+-----------------+----------+-----------------------------------------+
| Manning's N     | 0.011    | RUSLE Project; C23ONONC for Fresno      |
| Value (MNGN)    |          | onion crops which share most field      |
|                 |          | conditions with garlic (USDA, 2000).    |
+-----------------+----------+-----------------------------------------+
| USLE C Factor   | 0.5      | RUSLE Project; C23ONONC for Fresno      |
| (USLEC)         | 21-0.732 | onion crops which share most field      |
|                 |          | conditions with garlic (USDA, 2000).    |
+-----------------+----------+-----------------------------------------+

[]{.mark}

[]{.mark}

+---------------+---------------------+--------------------------------+
| **Table 4.    |                     |                                |
| PRZM 3.12     |                     |                                |
| Cerini Clay   |                     |                                |
| loam Soil     |                     |                                |
| Parameters    |                     |                                |
| Fresno,       |                     |                                |
| California -- |                     |                                |
| Garlic.**     |                     |                                |
+---------------+---------------------+--------------------------------+
| **Parameter** | **Value**           | **Source/Comments**            |
+---------------+---------------------+--------------------------------+
| Total Soil    | 157 cm              | NRCS Soil Data Mart (SDM)      |
| Depth (CORED) |                     | (http                          |
|               |                     | ://soildatamart.nrcs.usda.gov) |
+---------------+---------------------+--------------------------------+
| Number of     | 5                   | NRCS Soil Data Mart (SDM)      |
| Horizons      |                     | ([http://soild                 |
| (NHORIZ)      |                     | atamart.nrcs.usda.gov](http:// |
|               |                     | soildatamart.nrcs.usda.gov/)). |
+---------------+---------------------+--------------------------------+
| Horizon       | 10 cm (HORIZN = 1)  | NRCS Soil Data Mart (SDM)      |
| Thickness     |                     | ([http://soild                 |
| (THKNS)       | 3 cm (HORIZN = 2)   | atamart.nrcs.usda.gov](http:// |
|               |                     | soildatamart.nrcs.usda.gov/)). |
|               | 51 cm (HORIZN = 3)  | The top horizon was split into |
|               |                     | two horizons as per PRZM       |
|               | 25 cm (HORIZN = 4)  | Scenario Guidance (EPA, 2004). |
|               |                     |                                |
|               | 68 cm (HORIZN = 5)  |                                |
+---------------+---------------------+--------------------------------+
| Bulk Density  | 1.45 g/cm^3^        | NRCS Soil Data Mart (SDM)      |
| (BD)          | (HORIZN = 1)        | ([http://soild                 |
|               |                     | atamart.nrcs.usda.gov](http:// |
|               | 1.45 g/cm^3^        | soildatamart.nrcs.usda.gov/)). |
|               | (HORIZN = 2)        | Midpoint of the reported       |
|               |                     | range. PRZM Scenario Guidance  |
|               | 1.5 g/cm^3^ (HORIZN | (EPA, 2004).                   |
|               | = 3)                |                                |
|               |                     |                                |
|               | 1.45 g/cm^3^        |                                |
|               | (HORIZN = 4)        |                                |
|               |                     |                                |
|               | 1.45 g/cm^3^        |                                |
|               | (HORIZN = 5)        |                                |
+---------------+---------------------+--------------------------------+
| Initial Water | 0.313 cm^3^/cm^3^   | NRCS Soil Data Mart (SDM);     |
| Content       | (HORIZN =1)         | values are mean 1/3-bar water  |
| (THETO)       |                     | contents of Cerini clay loam   |
|               | 0.313 cm^3^/cm^3^   | soils.                         |
|               | (HORIZN =2)         |                                |
|               |                     |                                |
|               | 0.326 cm^3^/cm^3^   |                                |
|               | (HORIZN = 3)        |                                |
|               |                     |                                |
|               | 0.236 cm^3^/cm^3^   |                                |
|               | (HORIZN = 4)        |                                |
|               |                     |                                |
|               | 0.198 cm^3^/cm^3^   |                                |
|               | (HORIZN = 5)        |                                |
+---------------+---------------------+--------------------------------+
| Compartment   | 0.1 cm (HORIZN = 1) | NRCS Soil Data Mart (SDM)      |
| Thickness     |                     | ([http://soild                 |
| (DPN)         | 3 cm (HORIZN = 2)   | atamart.nrcs.usda.gov](http:// |
|               |                     | soildatamart.nrcs.usda.gov/)). |
|               | 3 cm (HORIZN = 3)   | PRZM Scenario Guidance (EPA,   |
|               |                     | 2004).                         |
|               | 5 cm (HORIZN = 4)   |                                |
|               |                     |                                |
|               | 4 cm (HORIZN = 5)   |                                |
+---------------+---------------------+--------------------------------+
| Field         | 0.313 cm^3^/cm^3^   | NRCS Soil Data Mart (SDM);     |
| Capacity      | (HORIZN =1)         | values are mean 1/3-bar water  |
| (THEFC)       |                     | contents of Cerini clay loam   |
|               | 0.313 cm^3^/cm^3^   | soils.                         |
|               | (HORIZN =2)         |                                |
|               |                     |                                |
|               | 0.326 cm^3^/cm^3^   |                                |
|               | (HORIZN = 3)        |                                |
|               |                     |                                |
|               | 0.236 cm^3^/cm^3^   |                                |
|               | (HORIZN = 4)        |                                |
|               |                     |                                |
|               | 0.198 cm^3^/cm^3^   |                                |
|               | (HORIZN = 5)        |                                |
+---------------+---------------------+--------------------------------+
| Wilting Point | 0.173 cm^3^/cm^3^   | NRCS Soil Data Mart (SDM);     |
| (THEWP)       | (HORIZN =1)         | values are mean 15-bar water   |
|               |                     | contents of Cerini clay loam   |
|               | 0.173 cm^3^/cm^3^   | soils.                         |
|               | (HORIZN =2)         |                                |
|               |                     |                                |
|               | 0.195 cm^3^/cm^3^   |                                |
|               | (HORIZN = 3)        |                                |
|               |                     |                                |
|               | 0.150 cm^3^/cm^3^   |                                |
|               | (HORIZN = 4)        |                                |
|               |                     |                                |
|               | 0.115 cm^3^/cm^3^   |                                |
|               | (HORIZN = 5)        |                                |
+---------------+---------------------+--------------------------------+
| Organic       | 0.46% (HORIZN = 1)  | NRCS SDM; values for horizons  |
| Carbon        |                     | 1 to 3 = mean %OM / 1.724.     |
| Content (OC)  | 0.46% (HORIZN = 2)  | PRZM Scenario Guidance (EPA,   |
|               |                     | 2004).                         |
|               | 0.41% (HORIZN = 3)  |                                |
|               |                     |                                |
|               | 0.23% (HORIZN = 4)  |                                |
|               |                     |                                |
|               | 0.17% (HORIZN = 5)  |                                |
+---------------+---------------------+--------------------------------+

[]{.mark}

[]{.mark}

***Sensitive Parameter Uncertainties***

[USLEC]{.underline}

Selected onion crops as closest match to garlic parameters for USLEC
values. Garlic and onions are both grown in rows on raised soil beds
with mechanical harvesting.

[]{.mark}

[]{.mark}

  ------------------------------------------------------------------------ ----------- -------- -------------- ----------------- ---------- --------- ------- -------- -------- -------- --------------- --------------
  **Table 5. Garlic Bearing Soils of Fresno, Kern, and Kings Counties                                                                                                                                    
  (California) Ranked by Area.**                                                                                                                                                                         

  **Soil**                                                                 **Total     **%      **Drainage**   **Erodibility**   **Slopes   **pH**    **OM    **%      **%      **%      **Garlic        
                                                                           Acreage**   Area**                                    (%)**                (%)**   Sand**   Silt**   Clay**   (tons)**        

                                                                                                                                                                                         **Irrigated**   **Non-Irr.**

  [CIERVO](http://ortho.ftw.nrcs.usda.gov/osd/dat/C/CIERVO.html)           92,670      22.78%   C/D            0.28              0-2        8.2       0.9     32       28       40       8.3-8.8         \-

  [CERINI](http://ortho.ftw.nrcs.usda.gov/osd/dat/C/CERINI.html)           76,200      18.74%   C              0.37              0-2        7.7       0.8     32       40       28       10.8            \-

  [CALFLAX](http://ortho.ftw.nrcs.usda.gov/osd/dat/C/CALFLAX.html)         54,140      13.31%   C              0.37              0-1        8         0.8     28       40       32       8.8             \-

  [WESTHAVEN](http://ortho.ftw.nrcs.usda.gov/osd/dat/W/WESTHAVEN.html)     50,290      12.36%   C/B            0.37              0-2        7.6-7.8   1.2     30-35    40-45    20-30    8.8-10          \-

  [HESPERIA](http://ortho.ftw.nrcs.usda.gov/osd/dat/H/HESPERIA.html)       27,871      6.85%    B              0.32              0-9        7.3-7.9   0.25    67.4     19.6     13       13-14           \-

  [PANOCHE](http://ortho.ftw.nrcs.usda.gov/osd/dat/P/PANOCHE.html)         27,870      6.85%    B              0.37              0-2        7.8       0.7     35       37       28       8               \-

  [LETHENT](http://ortho.ftw.nrcs.usda.gov/osd/dat/L/LETHENT.html)         26,979      6.63%    C              0.37              0-1        8         2       35       37       28       6-9.5           \-

  [EXCELSIOR](http://ortho.ftw.nrcs.usda.gov/osd/dat/E/EXCELSIOR.html)     20,110      4.94%    B              0.28              0-2        7.8       0.8     60       28       12       9.2             \-

  [POSOCHANET](http://ortho.ftw.nrcs.usda.gov/osd/dat/P/POSOCHANET.html)   16,430      4.04%    C              0.32              0-1        7.9       1.4     32       34       34       7.5             \-

  [MILHAM](http://ortho.ftw.nrcs.usda.gov/osd/dat/M/MILHAM.html)           7,700       1.89%    B              0.32              0-2        7.4       0.5     59       22       19       7.5             \-

  [ARVIN](http://ortho.ftw.nrcs.usda.gov/osd/dat/A/ARVIN.html)             3,480       0.86%    B              0.43              2-5        7         0.75    65.7     22.8     11.5     14              \-

  [DIGIORGIO](http://ortho.ftw.nrcs.usda.gov/osd/dat/D/DIGIORGIO.html)     2,982       0.73%    B              0.2               0-2        7.9       0.75    55.1     17.4     27.5     13              \-
  ------------------------------------------------------------------------ ----------- -------- -------------- ----------------- ---------- --------- ------- -------- -------- -------- --------------- --------------

**Contact**

**Bob Ehn**

Farm Advisor / UC Cooperative Extension

1720 S. Maple Ave.

Fresno, CA 93702

Phone: (559) 297-9322

Email: <robertehn@scbcglobal.net>

**Works Cited**

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, DC.

EPA. 2004. 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, DC.

EPA. 2005. Irrigation Guidance for developing PRZM Scenarios. June 15,
2005.

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 KY 40506. pp
286.

TWCII. 2006. Averages and Records for Fresno, CA. The Weather Channel
Interactive, Inc. Online at:
http://www.weather.com/outlook/recreation/outdoors/wxclimatology/monthly/graph/USCA0406

USDA. 1990. Davis, F.M., R.A. Leonard, W.G. Knisel. GLEAMS User Manual,
Version 1.8.55. U.S. Department of Agriculture, Agricultural Research
Service (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).

USDA. 2002. 2002 Census of Agriculture. U.S. Department of Agriculture,
National Agricultural Statistics Service (NASS). Online at:
<http://www.nass.usda.gov/census/census02/preliminary/2002censusdates.htm>.

USDA. 2003. Official Series Description --CERINI Series. U.S. Department
of Agriculture, Natural Resources Conservation Service (NRCS). Dec.
2006. Online at: <http://ortho.ftw.nrcs.usda.gov/osd/dat/C/CERINI.html>

USDA. 2004. Crop Profile for Garlic in California. U.S. Department of
Agriculture, Pest Management Centers. August 2004. Online at:
http://www.ipmcenters.org/CropProfiles/docs/CAgarlic.html.

USDA. 2006. Soil Survey Areas of Fresno, Kings, and Kern Counties. U.S.
Department of Agriculture, Natural Resources Conservation Service
(NRCS), Soil Data Mart. March 1, 2006. Online at:
[http://soildatamart.nrcs.usda.gov](http://soildatamart.nrcs.usda.gov/).