**CALIFORNIA POTATOES**

Kern County is the major potato production area in the San Joaquin
Valley (Figure 1), constituting nearly half the total acreage in
California (VRIC, undated(a); Areas of Potato Production in California).
Kern County potato acreage rose from only a few hundred acres before
1940 to approximately 65,000 acres in the early 1950\'s. In recent
years, 35,000 to 40,000 acres have been planted to potatoes annually
(VRIC, undated(a); Areas of Potato Production in California). In
addition, based on 2005 California Pesticide Usage Data (CalPIP, 2006),
approximately 64% of all pesticides applied to potatoes in California
(based on total pounds chemical applied) was applied in Kern County. The
majority of potatoes grown in the San Joaquin Valley are the White Rose
variety (VRIC, undated(b); Potato Varieties Grown in California).

Typical cropping practices include the chopping and shredding of the
previous crop, mulching, precision tillage, levelling, and sprinkler
irrigation practices (VRIC, 1977; UC Cooperative Extension Farm
Advisor). Sprinkler irrigation is used on 99% of crop and furrow or rill
irrigation is used on 1%, this allows precise application of water,
nutrients, and crop enhancement materials (USDA, 2000a). Potatoes have a
shallow, sparse root system and prefer very well-drained soil (e.g.,
loamy sand, sandy loam, high organic) and need frequent light
irrigation, 1 to 2 times a week. The crop is sprinkler irrigated
throughout the season (VRIC, 2000a). Potatoes are grown as an
alternating crop and the crops preceding potatoes are important for
several reasons; it is best if the previous crop\'s roots (e.g.,
carrots) penetrate to a greater soil depth than that needed by the
potato plant; and in the San Joaquin Valley, soybeans have been found to
prevent potato scab buildup (UC Cooperative Extension Farm Advisor);
VRIC, 1977).

Metfile W23155 is the meteorological data set representative of
Bakersfield, CA. The station is situated in the center of Kern County,
located in the extreme southern end of the great San Joaquin Valley and
is partially surrounded by a horseshoe-shaped rim of mountains (NOAA,
2006). These zones of variation may be classified as valley, mountain,
and desert areas, however, the overall climate can be classified as warm
and semi-arid (NOAA, 2006). Its data were collected at the Meadows Field
(WBAN 23155) in Bakersfield, CA, which receives an average annual
rainfall of around 6.49 inches (NOAA, 2006). There is only one wet
season during the year, as 90% of all precipitation falls from October
through April (NOAA, 2006; TWCII, 2006). Snow in the valley is
infrequent, with only a trace occurring in about one year out of seven
(NOAA, 2006).

The Lewkalb series is the most common hydrologic group C soil found in
Kern County where nearly half of all potatoes are grown (VRIC,
undated(a); Table 5). It is a Coarse-loamy, mixed, superactive,
calcareous, thermic Duric Torriorthents soil found on slopes of 0 to 2%.
Potatoes in this area are generally grown on level ground (J. Nunez,
personal communication). The soils are used mainly for range, as well as
irrigated crops such as cotton, alfalfa, sugar beets, potatoes, and
carrots are grown (USDA, 2001). The Lewkalb series was selected for this
scenario because it supports potato production (USDA, 2001), is located
in the highest potato production area in the state, is located in the
highest potato pesticide usage area of the state, and because it is
among the soils most vulnerable to runoff and erodibility in the area
(Table 5).

The majority of potato bearing soils are in hydrologic group B (Table
5). The Lewkalb series however is a Hydrologic Group C soil and is
listed as supporting potato production (Table 5; USDA, 2001). Lewkalb
potato bearing soils have a USLE K factor of 0.32, which is common to
92% of potato bearing soils and includes the 90^th^ percentile of these
soils in erodibility (Table 5). Approximately 94% of potato bearing
soils have a pH lower than Lewkalb soils. However, soil pH is not
currently a PRZM input parameter and is not expected to often affect
chemical fate in the acidic range. Based on the official soil series
description (OSD) (USDA, 2001), Lewkalb soils have an A horizon from 0
to 23 inches (0-58 cm) deep and a C horizon from 23 to 65 inches (58-165
cm) deep. The soil parameters selected for this scenario were obtained
from the USDA National Soils Characterization Database (NSCD) for Lekalb
Sandy Loam. It is noted that horizon thicknesses generally agree between
the OSD and NSCD, with slight variation.

+----------------------+-----------+-----------------------------------+
| **Table 1. PRZM 3.12 |           |                                   |
| Climate and Time     |           |                                   |
| Parameters for Kern  |           |                                   |
| County, California   |           |                                   |
| -- Potato.**         |           |                                   |
+======================+===========+===================================+
| **Parameter**        | **Value** | **Source/Comments**               |
+----------------------+-----------+-----------------------------------+
| Starting Date        | Jan. 1,   | Meteorological File from          |
|                      | 1961      | Bakersfield (Kern County), CA     |
|                      |           | (W23155).                         |
+----------------------+-----------+-----------------------------------+
| Ending Date          | Dec. 31,  | Meteorological File from          |
|                      | 1990      | Bakersfield (Kern County),        |
|                      |           | (W23155).                         |
+----------------------+-----------+-----------------------------------+
| Pan Evaporation      | 0.70      | PRZM Manual Figure 5.1. Value     |
| Factor (PFAC)        |           | represents central California.    |
+----------------------+-----------+-----------------------------------+
| Snowmelt Factor      | 0         | The Weather Channel Interactive,  |
| (SFAC)               |           | Inc. (TWCII, 2006)                |
+----------------------+-----------+-----------------------------------+
| Minimum Depth of     | 25.0 cm   | PRZM Manual, Figure 5.2 (EPA,     |
|                      |           | 1998)                             |
| Evaporation (ANETD)  |           |                                   |
|                      |           | Set to the midpoint of the        |
|                      |           | reported range.                   |
+----------------------+-----------+-----------------------------------+

+----------------------+-----------+-----------------------------------+
| **Table 2. PRZM 3.12 |           |                                   |
| Erosion and          |           |                                   |
| Landscape Parameters |           |                                   |
| for Kern County,     |           |                                   |
| California --        |           |                                   |
| Potato.**            |           |                                   |
+======================+===========+===================================+
| **Parameter**        | **Value** | **Source/Comments**               |
+----------------------+-----------+-----------------------------------+
| Method to Calculate  | 4 (MUSS)  | Guidance for Selecting Field Crop |
| Erosion (ERFLAG)     |           | and Orchard Scenario Input        |
|                      |           | Parameters (EPA, 2004)            |
+----------------------+-----------+-----------------------------------+
| USLE K Factor        | 0.32 tons | USDA NRCS Soil Data Mart          |
| (USLEK)              | EI^-1\*^  | (<htt                             |
|                      |           | p://soildatamart.nrcs.usda.gov/>) |
|                      |           |                                   |
|                      |           | Value listed for the soil series  |
|                      |           | Lewkalb                           |
+----------------------+-----------+-----------------------------------+
| USLE LS Factor       | 0.2       | PRZM Manual, [Table               |
| (USLELS)             |           | 5-5](../../../Me                  |
|                      |           | tadata%20Support%20Documents/Tabl |
|                      |           | e%205-5_USLELS_PRZM%20Manual.pdf) |
|                      |           | (EPA, 1998); LS equation (Haan    |
|                      |           | and Barfield, 1978)               |
|                      |           |                                   |
|                      |           | LS value for 400' slope length    |
|                      |           | and 1% slope                      |
+----------------------+-----------+-----------------------------------+
| USLE P Factor        | 1.0       | Potatoes are grown with no        |
| (USLEP)              |           | contour practices. Joe Nunez,     |
|                      |           | Farm Advisor, University of       |
|                      |           | California Cooperative Extension  |
|                      |           |                                   |
|                      |           | Default for potatoes with no      |
|                      |           | contour practices. PRZM Manual,   |
|                      |           | Table 5-6 (EPA, 1998)             |
+----------------------+-----------+-----------------------------------+
| Field Area (AFIELD)  | 172 ha    | Area of Shipman Reservoir         |
|                      |           | watershed (EPA, 1999)             |
+----------------------+-----------+-----------------------------------+
| NRCS Hyetograph      | 1         | PRZM Manual, Figure 5.12 (EPA,    |
| (IREG)               |           | 1998)                             |
+----------------------+-----------+-----------------------------------+
| Slope (SLP)          | 1%        | Midpoint of the soil range (EPA,  |
|                      |           | 2004). Potatoes generally are not |
|                      |           | grown on a slope. Joe Nunez, Farm |
|                      |           | Advisor, University of California |
|                      |           | Cooperative Extension             |
|                      |           |                                   |
|                      |           | USDA 2002a                        |
|                      |           | (http://soils.usda.gov)           |
+----------------------+-----------+-----------------------------------+
| Hydraulic Length     | 600 m     | Shipman Reservoir (EPA, 1999)     |
| (HL)                 |           |                                   |
+----------------------+-----------+-----------------------------------+
| Irrigation Flag      | 1         | Crop requires frequent light      |
| (IRFLAG)             |           | irrigation (sprinkler) 1 to 2     |
|                      |           | times a week throughout the       |
|                      |           | season. Joe Nunez, Farm Advisor,  |
|                      |           | University of California          |
|                      |           | Cooperative Extension             |
+----------------------+-----------+-----------------------------------+
| IRTYPE               | 3         | Joe Nunez, Farm Advisor,          |
|                      | (S        | University of California          |
|                      | prinkler) | Cooperative Extension             |
+----------------------+-----------+-----------------------------------+
| Leaching Factor      | 0.1       | Irrigation Guidance for           |
| (FLEACH)             |           | developing PRZM Scenario, Table   |
|                      |           | 3; (June 15, 2005).               |
+----------------------+-----------+-----------------------------------+
| Fraction of Water    | 0.5       | Set to default as per Irrigation  |
| Capacity when        |           | Guidance for developing PRZM      |
| Irrigation is        |           | Scenario, Table 3; (EPA 2005).    |
| Applied (PCDEPL)     |           |                                   |
+----------------------+-----------+-----------------------------------+
| Maximum Rate at      | 0.1 cm    | Set to default as per Irrigation  |
| which Irrigation is  | hr^-1^    | Guidance for developing PRZM      |
| Applied (RATEAP)     |           | Scenario, Table 3; (EPA 2005).    |
+----------------------+-----------+-----------------------------------+

+----------------------+-----------+-----------------------------------+
| **Table 3. PRZM 3.12 |           |                                   |
| Crop Parameters for  |           |                                   |
| Kern County,         |           |                                   |
| California --        |           |                                   |
| Potato.**            |           |                                   |
+======================+===========+===================================+
| **Parameter**        | **Value** | **Source/Comments**               |
+----------------------+-----------+-----------------------------------+
| Initial Crop         | 1         | Set to one for all crops          |
| (INICRP)             |           |                                   |
|                      |           | Guidance for Selecting Field Crop |
|                      |           | and Orchard Scenario Input        |
|                      |           | Parameters (EPA, 2004).           |
+----------------------+-----------+-----------------------------------+
| Initial Surface      | 3         | Material is usually left behind   |
| Condition            |           | and the field is then fertilized. |
|                      |           | Joe Nunez, Farm Advisor,          |
| (ISCOND)             |           | University of California          |
|                      |           | Cooperative Extension             |
+----------------------+-----------+-----------------------------------+
| Number of Different  | 1         | Set to number of crops in         |
| Crops (NDC)          |           | simulation.                       |
+----------------------+-----------+-----------------------------------+
| Number of Cropping   | 30        | Meteorological File from          |
| Periods (NCPDS)      |           | Bakersfield (Kern County), CA     |
|                      |           | (W23155).                         |
+----------------------+-----------+-----------------------------------+
| Maximum rainfall     | 0.15      | Recommended value for potatoes    |
| interception storage |           |                                   |
| of crop (CINTCP)     |           | PRZM Manual, Table 5-4 (EPA,      |
|                      |           | 1998) and Guidance for Selecting  |
|                      |           | Field Crop and Orchard Scenario   |
|                      |           | Input Parameters (EPA, 2004).     |
+----------------------+-----------+-----------------------------------+
| Maximum Active Root  | 91 cm     | 3 feet maximum. Joe Nunez, Farm   |
| Depth (AMXDR)        |           | Advisor, University of California |
|                      |           | Cooperative Extension             |
|                      |           |                                   |
|                      |           | PRZM Manual, Table 5-9 (15-45 cm) |
|                      |           | (EPA, 1998)                       |
+----------------------+-----------+-----------------------------------+
| Maximum Canopy       | 100       | Joe Nunez, Farm Advisor,          |
| Coverage (COVMAX)    |           | University of California          |
|                      |           | Cooperative Extension             |
+----------------------+-----------+-----------------------------------+
| Soil Surface         | 3         | Material is usually left behind   |
| Condition After      |           | and the field is then fertilized. |
| Harvest (ICNAH)      |           | Joe Nunez, Farm Advisor,          |
|                      |           | University of California          |
|                      |           | Cooperative Extension             |
+----------------------+-----------+-----------------------------------+
| Date of Crop         | 16/02     | Potatoes are planted Jan through  |
| Emergence            |           | Mar and emergence is 2 ½ weeks    |
|                      |           | later. Joe Nunez, Farm Advisor,   |
| (EMD, EMM, IYREM)    |           | University of California          |
|                      |           | Cooperative Extension             |
+----------------------+-----------+-----------------------------------+
| Date of Crop         | 15/05     | Potatoes mature approximately 90  |
| Maturity             |           | days after emergence Joe Nunez,   |
|                      |           | Farm Advisor, University of       |
| (MAD, MAM, IYRMAT)   |           | California Cooperative Extension  |
+----------------------+-----------+-----------------------------------+
| Date of Crop Harvest | 15/06     | Potatoes are harvested            |
| (HAD, HAM, IYRHAR)   |           | approximately 120 days after      |
|                      |           | emergence. Joe Nunez, Farm        |
|                      |           | Advisor, University of California |
|                      |           | Cooperative Extension             |
+----------------------+-----------+-----------------------------------+
| Maximum Dry Weight   | 0.0       | Not used in scenario (EPA, 2004)  |
| (WFMAX)              |           |                                   |
+----------------------+-----------+-----------------------------------+
| Maximum Canopy       | 60        | Canopy height of potatoes in CA   |
| Height (HTMAX)       |           | ranges from 20 inches to 2 feet.  |
|                      |           | Joe Nunez, Farm Advisor,          |
|                      |           | University of California          |
|                      |           | Cooperative Extension and PRZM    |
|                      |           | Manual, Table 5-16 (EPA, 1998)    |
+----------------------+-----------+-----------------------------------+
| SCS Curve Number     | 86, 81,   | Gleams Manual Table H-4 (USDA,    |
| (CN)                 | 85        | 1990); fallow = SR; cropping and  |
|                      |           | residue = SR poor condition. Joe  |
|                      |           | Nunez, Farm Advisor, University   |
|                      |           | of California Cooperative         |
|                      |           | Extension and PRZM Manual         |
+----------------------+-----------+-----------------------------------+
| Manning's N Value    | 0.014     | RUSLE Project; C23PIPIC for       |
| (MNGN)               |           | California (Fresno) Irish Potato  |
|                      |           | with conventional till and no     |
|                      |           | cover (cover code = 6) (USDA,     |
|                      |           | 2000b). These data are the        |
|                      |           | closest to Kern County with       |
|                      |           | similar cropping practices.       |
+----------------------+-----------+-----------------------------------+
| USLE C Factor        | 0.047 -   | RUSLE Project; C23PIPIC for       |
| (USLEC)              | 0.826     | California (Fresno) Irish Potato  |
|                      |           | with conventional till and no     |
|                      |           | cover (cover code = 6) (USDA,     |
|                      |           | 2000b). These data are the        |
|                      |           | closest to Kern County with       |
|                      |           | similar cropping practices.       |
+----------------------+-----------+-----------------------------------+

+------------------+-------------------+------------------------------+
| **Table 4. PRZM  |                   |                              |
| 3.12 Lewkalb     |                   |                              |
| Sandy Loam Soil  |                   |                              |
| Parameters for   |                   |                              |
| Kern County,     |                   |                              |
| California --    |                   |                              |
| Potato.**        |                   |                              |
+==================+===================+==============================+
| **Parameter**    | **Value**         | **Source/Comments**          |
+------------------+-------------------+------------------------------+
| Total Soil Depth | 152 cm            | NRCS Soil Characterization   |
| (CORED)          |                   | Database (SCD)               |
|                  |                   | (ht                          |
|                  |                   | tp://ssldata.nrcs.usda.gov/) |
+------------------+-------------------+------------------------------+
| Number of        | 6                 | NRCS Soil Characterization   |
| Horizons         |                   | Database (SCD)               |
| (NHORIZ)         |                   | (htt                         |
|                  |                   | p://ssldata.nrcs.usda.gov/); |
|                  |                   | soil consists of two         |
|                  |                   | horizons: A and B (although  |
|                  |                   | the official soils           |
|                  |                   | description reclassified the |
|                  |                   | B horizon as a C horizon).   |
|                  |                   | The A horizon spans scenario |
|                  |                   | horizons 1 and 2 in order to |
|                  |                   | conform to PRZM input        |
|                  |                   | requirements. Lower two      |
|                  |                   | horizons consolidated for    |
|                  |                   | simplicity due to similar    |
|                  |                   | properties as per PRZM input |
|                  |                   | guidance (EPA, 2004).        |
+------------------+-------------------+------------------------------+
| Horizon          | 10 cm (HORIZN =   | NRCS Soil Characterization   |
| Thickness        | 1)                | Database (SCD)               |
| (THKNS)          |                   | (htt                         |
|                  | 20 cm (HORIZN =   | p://ssldata.nrcs.usda.gov/); |
|                  | 2)                | Lower two horizons           |
|                  |                   | consolidated for simplicity  |
|                  | 40 cm (HORIZN =   | due to similar properties as |
|                  | 3)                | per PRZM input guidance      |
|                  |                   | (EPA, 2004).                 |
|                  | 18 cm (HORIZN =   |                              |
|                  | 4)                |                              |
|                  |                   |                              |
|                  | 10 cm (HORIZN =   |                              |
|                  | 5)                |                              |
|                  |                   |                              |
|                  | 54 cm (HORIZN =   |                              |
|                  | 6)                |                              |
+------------------+-------------------+------------------------------+
| Bulk Density     | 1.55 g/cm^3^      | NRCS Soil Data Mart (SDM)    |
| (BD)             | (HORIZN = 1)      | ([http://soildatam           |
|                  |                   | art.nrcs.usda.gov](http://so |
|                  | 1.55 g/cm^3^      | ildatamart.nrcs.usda.gov/)); |
|                  | (HORIZN = 2)      | values are mean 1/3-bar      |
|                  |                   | moist bulk densities of a    |
|                  | 1.55 g/cm^3^      | soil sampled as a Lewkalb.   |
|                  | (HORIZN = 3)      | No SCD data were found to    |
|                  |                   | correlate with Lewkalb       |
|                  | 1.5 g/cm^3^       | soils. SDM values were       |
|                  | (HORIZN = 4)      | incomplete, leading to       |
|                  |                   | errors in PRZM.              |
|                  | 1.5 g/cm^3^       |                              |
|                  | (HORIZN = 5)      |                              |
|                  |                   |                              |
|                  | 1.55 g/cm^3^      |                              |
|                  | (HORIZN = 6)      |                              |
+------------------+-------------------+------------------------------+
| Initial Water    | 0.091 cm^3^/cm^3^ | SDM values were incomplete,  |
| Content (THETO)  | (HORIZN =1)       | leading to errors in PRZM.   |
|                  |                   | Values are based on Field    |
|                  | 0.091 cm^3^/cm^3^ | Capacity computed using      |
|                  | (HORIZN =2)       | Rawls and Brakensiek method  |
|                  |                   | fo field capacity matric     |
|                  | 0.101 cm^3^/cm^3^ | potential (-0.33 bar) as per |
|                  | (HORIZN =3)       | PRZM manual (EPA, 1998).     |
|                  |                   |                              |
|                  | 0.135 cm^3^/cm^3^ |                              |
|                  | (HORIZN =4)       |                              |
|                  |                   |                              |
|                  | 0.203 cm^3^/cm^3^ |                              |
|                  | (HORIZN =5) 0.125 |                              |
|                  | cm^3^/cm^3^       |                              |
|                  | (HORIZN =6)       |                              |
+------------------+-------------------+------------------------------+
| Compartment      | 0.1 cm (HORIZN =  | NRCS Soil Characterization   |
| Thickness (DPN)  | 1)                | Database (SCD)               |
|                  |                   | (<http                       |
|                  | 5.0 cm (HORIZN =  | ://ssldata.nrcs.usda.gov/>); |
|                  | 2)                | (EPA, 2004)                  |
|                  |                   |                              |
|                  | 5.0 cm (HORIZN =  |                              |
|                  | 3)                |                              |
|                  |                   |                              |
|                  | 3.0 cm (HORIZN =  |                              |
|                  | 4)                |                              |
|                  |                   |                              |
|                  | 5.0 cm (HORIZN =  |                              |
|                  | 5)                |                              |
|                  |                   |                              |
|                  | 3.0 cm (HORIZN =  |                              |
|                  | 6)                |                              |
+------------------+-------------------+------------------------------+
| Field Capacity   | 0.091 cm^3^/cm^3^ | SDM values were incomplete,  |
| (THEFC)          | (HORIZN =1)       | leading to errors in PRZM.   |
|                  |                   | Values are based on Field    |
|                  | 0.091 cm^3^/cm^3^ | Capacity computed using      |
|                  | (HORIZN =2)       | Rawls and Brakensiek method  |
|                  |                   | as per PRZM manual (EPA,     |
|                  | 0.101 cm^3^/cm^3^ | 1998).                       |
|                  | (HORIZN =3)       |                              |
|                  |                   |                              |
|                  | 0.135 cm^3^/cm^3^ |                              |
|                  | (HORIZN =4)       |                              |
|                  |                   |                              |
|                  | 0.203 cm^3^/cm^3^ |                              |
|                  | (HORIZN =5) 0.125 |                              |
|                  | cm^3^/cm^3^       |                              |
|                  | (HORIZN =6)       |                              |
+------------------+-------------------+------------------------------+
| Wilting Point    | 0.010 cm^3^/cm^3^ | SDM values were incomplete,  |
| (THEWP)          | (HORIZN =1)       | leading to errors in PRZM.   |
|                  |                   | Values are based on wilting  |
|                  | 0.010 cm^3^/cm^3^ | point computed using Rawls   |
|                  | (HORIZN =2)       | and Brakensiek method for    |
|                  |                   | wilting point matric         |
|                  | 0.010 cm^3^/cm^3^ | potential (-15 bar) as per   |
|                  | (HORIZN =3)       | PRZM manual (EPA, 1998).     |
|                  |                   | Computed values for horizon  |
|                  | 0.008 cm^3^/cm^3^ | 6 was less than 0.001, but   |
|                  | (HORIZN =4)       | reported here as 0.001 to    |
|                  |                   | prevent errors in PRZM.      |
|                  | 0.002 cm^3^/cm^3^ |                              |
|                  | (HORIZN =5)       |                              |
|                  |                   |                              |
|                  | 0.001 cm^3^/cm^3^ |                              |
|                  | (HORIZN =6)       |                              |
+------------------+-------------------+------------------------------+
| Organic Carbon   | 0.14% (HORIZN =   | NRCS Soil Characterization   |
| Content (OC)     | 1)                | Database (SCD)               |
|                  |                   | (<http                       |
|                  | 0.14% (HORIZN =   | ://ssldata.nrcs.usda.gov/>); |
|                  | 2)                | Values were converted to %OM |
|                  |                   | for Rawls and Brakensiek     |
|                  | 0.09% (HORIZN =   | equation based on %OM =      |
|                  | 3)                | %OC\*1.724. Value for        |
|                  |                   | horizon 6 is the mean of the |
|                  | 0.16% (HORIZN =   | bottom two horizons (see     |
|                  | 4)                | NHORIZ note above).          |
|                  |                   |                              |
|                  | 0.25% (HORIZN =   |                              |
|                  | 5)                |                              |
|                  |                   |                              |
|                  | 0.11% (HORIZN =   |                              |
|                  | 6)                |                              |
+------------------+-------------------+------------------------------+

![](media/image1.png){width="8.749305555555555in"
height="5.294444444444444in"}

**Figure 1. 2002 harvested acres for potatoes based on USDA Census of
Agriculture (USDA, 2002b) for California and conterminous United States
(inset) Estimates do not include data for individual farms which NASS
has excluded to protect the identify of individual farms.**

  ------------------------------------------------------------------------ ----------- -------- -------------- ----------------- ---------- --------- ------- ----------- ----------- --------- ---------------------
  **Table 5. Potato Bearing Soils of Kern County, California Ranked by                                                                                                                          
  Area.**                                                                                                                                                                                       

  **Soil**                                                                 **Total     **%      **Drainage**   **Erodibility**   **Slopes   **pH**    **OM    **% Sand**  **% Silt**  **%       **Irish
                                                                           Acreage**   Area**                                    (%)**                (%)**                           Clay**    potatoes-IrrYield**

  [KIMBERLINA](http://ortho.ftw.nrcs.usda.gov/osd/dat/K/KIMBERLINA.html)   170655      36.15%   B              0.32              0-5        7.5       0.75    68.3-71.3   16.7-19.7   12        340

  [WASCO](http://ortho.ftw.nrcs.usda.gov/osd/dat/W/WASCO.html)             108895      23.07%   B              0.32              0-2        7         0.25    67.4-70.5   16.5-19.6   13        340

  [MILHAM](http://ortho.ftw.nrcs.usda.gov/osd/dat/M/MILHAM.html)           99800       21.14%   B              0.32              0-2        7.9       0.75    67.9        19.6        12.5      360

  [HESPERIA](http://ortho.ftw.nrcs.usda.gov/osd/dat/H/HESPERIA.html)       27871       5.90%    B              0.32              0-9        7.3-7.9   0.25    67.4        19.6        13        300-400

  [LEWKALB](http://ortho.ftw.nrcs.usda.gov/osd/dat/L/LEWKALB.html)         11580       2.45%    C              0.32              0-2        8.2       0.25    68.3        19.7        12        380

  [ROSAMOND](http://ortho.ftw.nrcs.usda.gov/osd/dat/R/ROSAMOND.html)       11292       2.39%    C              0.28              0-2        8.2       0.75    65.9        19.1        15        400

  [DRIVER](http://ortho.ftw.nrcs.usda.gov/osd/dat/D/DRIVER.html)           10260       2.17%    C              0.32              0-2        7.9       0.25    67.1        18.9        14        380

  [HAVALA](http://ortho.ftw.nrcs.usda.gov/osd/dat/H/HAVALA.html)           9632        2.04%    B              0.24              0-5        7.5       1.5     65.9        19.1        15        365

  [DESTAZO](http://ortho.ftw.nrcs.usda.gov/osd/dat/D/DESTAZO.html)         7410        1.57%    B              0.2               0-2        8.2       0.75    67.4        19.6        13        350

  [WHITEWOLF](http://ortho.ftw.nrcs.usda.gov/osd/dat/W/WHITEWOLF.html)     7162        1.52%    A              0.2               0-5        7.3       0.75    69.6-79.7   16.8-22.9   3.5-7.5   300

  [CHANAC](http://ortho.ftw.nrcs.usda.gov/osd/dat/C/CHANAC.html)           6670        1.41%    B              0.32              2-9        7.9       0.75    35.4        33.6        31        250

  [PLEITO](http://ortho.ftw.nrcs.usda.gov/osd/dat/P/PLEITO.html)           855         0.18%    C              0.24              2-5        7.5       1.5     55.1        17.4        27.5      250
  ------------------------------------------------------------------------ ----------- -------- -------------- ----------------- ---------- --------- ------- ----------- ----------- --------- ---------------------

***References***

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