**Southern Florida**

**Outdoor Ornamental Nursery Scenario**

[]{.mark}

This scenario is one of a suite of scenarios intended to represent
outdoor ornamental nursery scenarios in the United States. It should be
noted that nurseries are diverse and represent a range of topographic,
cultivation, and plant types. Scenarios, when possible have been
developed to represent conservative nursery practices that will yield
"high-end" runoff, but not unrealistic of actual nurseries in the area.
Similarly, selection of curve numbers are based on best available data
from TR-55 until further calibration can be performed using regional
runoff data, which at the time of scenario development is generally
unavailable for nurseries. Figure 1 provides an overview of available
curve numbers from TR-55 in order to provide context to the relative
magnitude of the curve number used in this scenario. The closest curve
number that could be associated with outdoor nurseries is for
"farmsteads", due to similar cover conditions. Curve numbers are
generally among the highest available, exceeded primarily by soils in
poor condition.

This scenario is parameterized to generally represent outdoor ornamental
nursery production in southern Florida. The scenario nominally
represents outdoor ornamental nurseries in Dade County, FL since it is
the county with the most number of acres in production in the region. In
2002, the state of Florida ranked 2^nd^ in the U.S. for total number of
ornamental nursery acres in the outdoors (i.e., not under glass), with
approximately 49,770 acres in the open (USDA, 2002). Approximately 16%
(7,888 acres) of the total outdoor acreage is located in Dade County.
Dade County has over 950 nurseries (Garofalo, 2002). Nursery operations
range from as small as 1-2 acres to large operations employing dozens of
workers. MLRA 156A dominates southern Florida and completely contains
Miami-Dade County.

[]{.mark}

The specific type of nursery represented is a container nursery that
grows primarily tropical plants and other woody ornamentals and vines.
There are three main types of nurseries in Florida: 1) field nurseries;
2) outdoor container operations; and 3) indoor, or greenhouse
operations. Indoor operations are not applicable for modeling pesticide
application and field runoff and are therefore not represented by this
scenario. Due to the warm climate in southern Florida, nurseries tend to
produce large, field-grown tropical material. Field nurseries typically
produce woody ornamentals planted directly in the ground which are later
dug, "balled-&- burlapped" for sale (Garofalo, 2002). Container
nurseries generally grow similar plants as field nurseries, however
plants are grown in pots and the ground is covered with a cloth that
prevents weed and root growth, but allows water to flow freely. The
nursery industry in Florida is dominated by container operations, with
nearly 80% of all operations producing container grown plants
(University of Florida, 2000).

Plants cultivated by outdoor nurseries are diverse. Field nurseries
typically produce palms, trees, and large shrubs. Many nurseries take
advantage of southern Florida's climate to grow tropical material
(Garofalo, 2002). Based on 2003 nursery production data (USDA, 2004a),
the largest number of nursery plants grown in Florida are broadleaf
evergreens (16 million plants), deciduous shrubs (17 million plants) and
"other woody ornamentals and vines" or those that do not fit in one of
the other USDA plant categories (23 million plants). These same
categories also receive the most pesticide applications (239, 363, and
293 thousand pounds a.i. per year, respectively) (USDA, 2004b). For this
scenario, crop parameters have been selected when possible to be
representative of typical outdoor nursery practices in southern Florida,
specifically Dade County. In general, this scenario represents field
nurseries growing mainly *tropical material and other woody ornamentals*
which are common in Dade County. Some nursery managers intercrop smaller
plants with larger ones to produce early income while others prefer to
plant even age blocks from which all plants are sold in a short time
period (Garofalo, 2002). For the purposes of this scenario, it is
assumed that container nurseries grow even aged plants.

[]{.mark}

Metfile W12839 is the closest meteorological station to Dade County, FL
and is within approximately 20 miles of the county centroid. Its data
were collected in Miami, FL located in the south-eastern part of the
state. The station is located approximately 4 meters above mean sea
level (AMSL) which is comparable to Dade County which generally ranges
from 2-4 meters AMSL. Miami receives an average rainfall of 59 inches
(NOAA, 2006) and most of the rainfall occurs during the hot and humid
rainy season (May-October). Irrigation is required year-round, even
during the rainy season (Garofalo, 2002).

[]{.mark}

Soils used for field nursery production consist of alkaline clay called
marl (Garofalo, 2002). Marl is found mainly in south-eastern Dade
County. Soil thickness varies from a few inches to several feet. Some
nurseries are located on engineered, or "made" soils consisting of a
gravely loam. Based on the Official Soil Survey of Dade County,
nurseries are located predominantly on the Perrine-Biscayne-Pennsuco
association used for field-grown trees and shrubs, ranging from 600 to
800 trees or shrubs per acre (USDA, 1987). According to the Soil Data
Mart (USDA, 2006a), the predominant soil series in Dade County is the
Biscayne (marl) series (Table 5). The Biscayne series consists of
shallow, poorly and very poorly drained, moderately or moderately
rapidly permeable soils over limestone in fresh water and tidal marshes
and sloughs, as well as in broad, low, coastal flats and elongated
sloughs in Southern Peninsular Florida (USDA, 2003). Exact locations and
geographic extent of nurseries in the region are not available;
therefore soils were selected based on soil recommendations of Garofalo
(2002), the Soil Survey of Dade County (USDA, 1987), the geographic
extent of nursery supporting soils in the area (USDA, 2006a), the
drainage group, slope, and erodibility. According to the official soil
series description for Biscayne soils (USDA, 2003), areas that have been
drained or those areas with water control are used for growing vegetable
crops, ornamental shrubs, and trees. Only one soil (Terra Ceia) in the
county was listed as a benchmark soil (USDA, 2006b) however it is of
lesser extent and more importantly is not listed as supporting
ornamental nursery crops (USDA, 2000a) and therefore was not used for
parameterization. In developing this scenario, preference was given to
selecting a soil that is in hydrologic group "C" or "D", and is capable
of supporting outdoor nurseries (EPA, 2004). The Biscayne series was
selected for this scenario since it is of large extent in Dade County
(USDA, 2003), is a hydrologic group D soil, and is capable of supporting
outdoor ornamental nursery production (USDA, 2003). Biscayne soils
represent the 90^th^ percentile of vulnerability in drainage for soils
in Dade County It is in the 90^th^ percentile for erodibility (0.32) and
is only exceeded in erodibility by one soil type (Table 5).

[]{.mark}

Biscayne is a Hydrologic Group D soil, which represents approximately
17% of the soils in Dade County (excluding urban soils) (Table 5).
Biscayne soils have a USLE K factor of 0.32, which is common to four
other soils in Dade County. Approximately 10% of Dade County soils have
a pH lower than Biscayne 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, Biscayne
soils have an A horizon from 0 to 5 inches (0-12 cm) deep, and a C
horizon from 5 to over 15 inches (12-38 cm) deep (USDA, 2003). Soil
parameters for this scenario were based on "Biscayne marl, drained"
soils.

[]{.mark}

+-----------------+----------+-----------------------------------------+
| []{.mark}       |          |                                         |
|                 |          |                                         |
| **Table 1. PRZM |          |                                         |
| 3.12 Climate    |          |                                         |
| and Time        |          |                                         |
| Parameters for  |          |                                         |
| Dade County, FL |          |                                         |
| -- Ornamental   |          |                                         |
| Nurseries.**    |          |                                         |
+-----------------+----------+-----------------------------------------+
| **Parameter**   | *        | **Source/Comments**                     |
|                 | *Value** |                                         |
+-----------------+----------+-----------------------------------------+
| Starting Date   | Jan. 1,  | Meteorological File Miami, FL (W12839)  |
|                 | 1961     |                                         |
+-----------------+----------+-----------------------------------------+
| Ending Date     | Dec. 31, | Meteorological File Miami, FL (W12839)  |
|                 | 1990     |                                         |
+-----------------+----------+-----------------------------------------+
| Pan Evaporation | 0.775    | PRZM Manual Figure 5.1. Value           |
| Factor (PFAC)   |          | represents most of southern Florida.    |
+-----------------+----------+-----------------------------------------+
| Snowmelt Factor | 0        | PRZM Manual guidance. No snowfall       |
| (SFAC)          |          | observed at Miami Int'l Airport         |
|                 |          | (NOWData, NOAA).                        |
+-----------------+----------+-----------------------------------------+
| Minimum Depth   | 32.5 cm  | PRZM Manual Figure 5.2 (EPA, 1998)      |
| of              |          |                                         |
|                 |          | Set to guidance default for free        |
| Evaporation     |          | draining soils.                         |
| (ANETD)         |          |                                         |
+-----------------+----------+-----------------------------------------+

[]{.mark}

+-----------------+--------+-------------------------------------------+
| **Table 2. PRZM |        |                                           |
| 3.12 Erosion    |        |                                           |
| and Landscape   |        |                                           |
| Parameters for  |        |                                           |
| Dade County,    |        |                                           |
| Florida --      |        |                                           |
| Ornamental      |        |                                           |
| Nurseries.**    |        |                                           |
+=================+========+===========================================+
| **Parameter**   | **V    | **Source/Comments**                       |
|                 | alue** |                                           |
+-----------------+--------+-------------------------------------------+
| Method to       | 4      | PRZM Guidance (EPA, 2004)                 |
| Calculate       | (MUSS) |                                           |
| Erosion         |        |                                           |
| (ERFLAG)        |        |                                           |
+-----------------+--------+-------------------------------------------+
| USLE K Factor   | 0.32   | USDA NRCS Soil Data Mart                  |
| (USLEK)         |        | (http://soildatamart.nrcs.usda.gov/)      |
|                 |        |                                           |
|                 |        | Value listed for the soil series Biscayne |
|                 |        | marl, drained.                            |
+-----------------+--------+-------------------------------------------+
| USLE LS Factor  | 0.2    | LS equation (Haan and Barfield, 1978)     |
| (USLELS)        |        |                                           |
|                 |        | LS value for 1 % slope and 400' slope     |
|                 |        | length                                    |
+-----------------+--------+-------------------------------------------+
| USLE P Factor   | 1.0    | Set to 1.0 for orchards as per PRZM       |
| (USLEP)         |        | Scenario Guidance (EPA, 2004).            |
+-----------------+--------+-------------------------------------------+
| Field Area      | 172 ha | Area of Shipman Reservoir watershed (PRZM |
| (AFIELD)        |        | Guidance, EPA, 2004)                      |
+-----------------+--------+-------------------------------------------+
| NRCS Hyetograph | 4      | PRZM Manual Figure 5.12 (EPA, 1998)       |
| (IREG)          |        |                                           |
+-----------------+--------+-------------------------------------------+
| Slope (SLP)     | 1%     | USDA NRCS Soil Data Mart                  |
|                 |        | (http://soildatamart.nrcs.usda.gov/)      |
|                 |        |                                           |
|                 |        | Mid-point for the soil series Biscayne    |
|                 |        | marl, drained (0-1.9%). PRZM Scenario     |
|                 |        | Guidance (EPA, 2004).                     |
+-----------------+--------+-------------------------------------------+
| Hydraulic       | 600 m  | Shipman Reservoir (PRZM Guidance, EPA,    |
| Length (HL)     |        | 2004)                                     |
+-----------------+--------+-------------------------------------------+
| Irrigation Flag | 1      | Irrigation is required year-round, even   |
| (IRFLAG)        |        | during the rainy season. (Garofalo et     |
|                 |        | al., 2002 The Commercial Ornamental       |
|                 |        | Horticulture                              |
|                 |        |                                           |
|                 |        | Industry in Miami-Dade County)            |
+-----------------+--------+-------------------------------------------+
| Number range    | 3      | 3 = over canopy sprinkler. Irrigation     |
| CH              |        | Guidance for developing PRZM Scenario,    |
| APTERIrrigation |        | Table 3; (June 15, 2005); and             |
| Type (IRTYP)    |        | (Muñoz-Carpena, 2003)                     |
+-----------------+--------+-------------------------------------------+
| Leaching Factor | 0.1    | Default value. Irrigation Guidance for    |
| (FLEACH)        |        | developing PRZM Scenario, Table 3; (June  |
|                 |        | 15, 2005).                                |
+-----------------+--------+-------------------------------------------+
| Fraction of     | 0.5    | Default value. Irrigation Guidance for    |
| Water Capacity  |        | developing PRZM Scenario, Table 3; (June  |
| when Irrigation |        | 15, 2005).                                |
| is Applied      |        |                                           |
| (PCDEPL)        |        |                                           |
+-----------------+--------+-------------------------------------------+
| Maximum Rate at | 0.1    | Default value. Irrigation Guidance for    |
| which           |        | developing PRZM Scenario, Table 1; (June  |
| Irrigation is   |        | 15, 2005). Set based on cropping curve    |
| Applied         |        | number.                                   |
| (RATEAP)        |        |                                           |
+-----------------+--------+-------------------------------------------+

[]{.mark}

[]{.mark}

+-----------------+--------+-------------------------------------------+
| **Table 3. PRZM |        |                                           |
| 3.12 Crop       |        |                                           |
| Parameters for  |        |                                           |
| Dade County,    |        |                                           |
| Florida --      |        |                                           |
| Ornamental      |        |                                           |
| Nurseries.**    |        |                                           |
+=================+========+===========================================+
| **Parameter**   | **V    | **Source/Comments**                       |
|                 | alue** |                                           |
+-----------------+--------+-------------------------------------------+
| Initial Crop    | 1      | Default value                             |
| (INICRP)        |        |                                           |
+-----------------+--------+-------------------------------------------+
| Initial Surface | 2      | 2 = cover crop. Grass is planted between  |
| Condition       |        | rows. Based on high-resolution color      |
|                 |        | aerial photography of ornamental          |
| (ISCOND)        |        | nurseries in Miami county.                |
+-----------------+--------+-------------------------------------------+
| Number of       | 1      | Set to number of crops in simulation.     |
| Different Crops |        | Default value.                            |
| (NDC)           |        |                                           |
+-----------------+--------+-------------------------------------------+
| Number of       | 30     | Set to weather data in meteorological     |
| Cropping        |        | file: Miami, FL (W12839)                  |
| Periods (NCPDS) |        |                                           |
+-----------------+--------+-------------------------------------------+
| Maximum         | 0.1    | Table 5-4 PRZM manual, light density      |
| rainfall        |        | crops (EPA, 1998).                        |
| interception    |        |                                           |
| storage of crop |        |                                           |
| (CINTCP)        |        |                                           |
+-----------------+--------+-------------------------------------------+
| Maximum Active  | 0 cm   | Set to zero to simulate container grown   |
| Root Depth      |        | operations. 80% of Florida's nursery      |
| (AMXDR)         |        | operations are containerized (University  |
|                 |        | of Florida, 2000).                        |
+-----------------+--------+-------------------------------------------+
| Maximum Canopy  | 60%    | Based on high-resolution color aerial     |
| Coverage        |        | photography of ornamental nurseries in    |
| (COVMAX)        |        | Miami county.                             |
+-----------------+--------+-------------------------------------------+
| Maximum Canopy  | 457 cm | Height varies widely as many different    |
| Height (HTMAX)  | (15ft) | cultivars are grown. Some nurseries sell  |
|                 |        | plants up to 15 feet                      |
|                 |        | (<http://ww                               |
|                 |        | w.nursery-report.com/Search/Default.asp>) |
+-----------------+--------+-------------------------------------------+
| Soil Surface    | 2      | 2 = cover crop. Grass is planted between  |
| Condition After |        | rows. Based on high-resolution color      |
| Harvest (ICNAH) |        | aerial photography of ornamental          |
|                 |        | nurseries in Miami county.                |
+-----------------+--------+-------------------------------------------+
| Date of Crop    | 1      | Values are set to keep E/T and canopy     |
| Emergence       | /01/61 | coverage terms working correctly for this |
|                 |        | evergreen scenario.                       |
| (EMD, EMM,      |        |                                           |
| IYREM)          |        |                                           |
+-----------------+--------+-------------------------------------------+
| Date of Crop    | 02     | Values are set to keep E/T and canopy     |
| Maturity        | /01/61 | coverage terms working correctly for this |
|                 |        | evergreen scenario.                       |
| (MAD, MAM,      |        |                                           |
| IYRMAT)         |        |                                           |
+-----------------+--------+-------------------------------------------+
| Date of Crop    | 31     | Values are set to keep E/T and canopy     |
| Harvest (HAD,   | /12/61 | coverage terms working correctly for this |
| HAM, IYRHAR)    |        | evergreen scenario.                       |
+-----------------+--------+-------------------------------------------+
| Maximum Dry     | 0.0    | Not used in scenario                      |
| Weight (WFMAX)  |        |                                           |
+-----------------+--------+-------------------------------------------+
| SCS Curve       | 86,    | TR-55, Table 2-2c (USDA 1986). Value for  |
| Number (CN)     | 86, 86 | farmsteads -- buildings, lanes,           |
|                 |        | driveways, and surrounding lots,          |
|                 |        | hydrologic group D.                       |
+-----------------+--------+-------------------------------------------+
| Manning's N     | 0.023  | RUSLE Project; Uc0STSTN for Tampa, FL     |
| Value (MNGN)    |        | strawberry with No Till (Soil disturbance |
|                 |        | is limited to a planting operation) and   |
|                 |        | light cover (cover code 5). These data    |
|                 |        | were used to approximate values for       |
|                 |        | nurseries in southern Florida as no data  |
|                 |        | for ornamental nurseries were included in |
|                 |        | the project. (USDA, 2000b)                |
+-----------------+--------+-------------------------------------------+
| USLE C Factor   | 0      | RUSLE Project; Uc0STSTN for Tampa, FL     |
| (USLEC)         | .023 - | strawberry with No Till (Soil disturbance |
|                 | 0.326  | is limited to a planting operation) and   |
|                 |        | light cover (cover code 5). These data    |
|                 |        | were used to approximate values for       |
|                 |        | nurseries in southern Florida as no data  |
|                 |        | for ornamental nurseries were included in |
|                 |        | the project. (USDA, 2000b). Note: RUSLE   |
|                 |        | dates and C factors from the RUSLE        |
|                 |        | project have been reordered and tied to   |
|                 |        | emergence dates.                          |
+-----------------+--------+-------------------------------------------+

[]{.mark}

+---------------+-------------------+---------------------------------+
| []{.mark}     |                   |                                 |
|               |                   |                                 |
| **Table 4.    |                   |                                 |
| PRZM 3.12     |                   |                                 |
| "Biscayne     |                   |                                 |
| marl,         |                   |                                 |
| drained" Soil |                   |                                 |
| Parameters    |                   |                                 |
| for Dade      |                   |                                 |
| County,       |                   |                                 |
| Florida --    |                   |                                 |
| Ornamental    |                   |                                 |
| Nurseries**   |                   |                                 |
+---------------+-------------------+---------------------------------+
| **Parameter** | **Value**         | **Source/Comments**             |
+---------------+-------------------+---------------------------------+
| Total Soil    | 38 cm             | NRCS Soil Data Mart (SDM)       |
| Depth (CORED) |                   | (htt                            |
|               |                   | p://soildatamart.nrcs.usda.gov) |
+---------------+-------------------+---------------------------------+
| Number of     | 3                 | NRCS Soil Data Mart (SDM)       |
| Horizons      |                   | ([http://so                     |
| (NHORIZ)      |                   | ildatamart.nrcs.usda.gov](http: |
|               |                   | //soildatamart.nrcs.usda.gov/)) |
|               |                   | The fourth horizon from SDM     |
|               |                   | excluded because it is bedrock. |
+---------------+-------------------+---------------------------------+
| Horizon       | 10 cm (HORIZN =   | NRCS Soil Data Mart (SDM)       |
| Thickness     | 1)                | ([http://soi                    |
| (THKNS)       |                   | ldatamart.nrcs.usda.gov](http:/ |
|               | 2 cm (HORIZN = 2) | /soildatamart.nrcs.usda.gov/)). |
|               |                   |                                 |
|               | 26 cm (HORIZN =   |                                 |
|               | 3)                |                                 |
+---------------+-------------------+---------------------------------+
| Bulk Density  | 1.1 g/cm^3^       | NRCS Soil Data Mart (SDM)       |
| (BD)          | (HORIZN = 1)      | ([http://soi                    |
|               |                   | ldatamart.nrcs.usda.gov](http:/ |
|               | 1.1 g/cm^3^       | /soildatamart.nrcs.usda.gov/)). |
|               | (HORIZN = 2)      | Midpoint of the reported range. |
|               |                   | PRZM Scenario Guidance (EPA,    |
|               | 1 g/cm^3^ (HORIZN | 2004).                          |
|               | = 3)              |                                 |
+---------------+-------------------+---------------------------------+
| Initial Water | 0.17 cm^3^/cm^3^  | NRCS Soil Data Mart (SDM);      |
| Content       | (HORIZN =1)       | values are mean 1/3-bar water   |
| (THETO)       |                   | contents of Biscayne marl,      |
|               | 0.17 cm^3^/cm^3^  | drained soils.                  |
|               | (HORIZN =2)       |                                 |
|               |                   |                                 |
|               | 0.17 cm^3^/cm^3^  |                                 |
|               | (HORIZN =3)       |                                 |
+---------------+-------------------+---------------------------------+
| Compartment   | 0.1 cm (HORIZN =  | NRCS Soil Data Mart (SDM)       |
| Thickness     | 1)                | ([http://soi                    |
| (DPN)         |                   | ldatamart.nrcs.usda.gov](http:/ |
|               | 2.0 cm (HORIZN =  | /soildatamart.nrcs.usda.gov/)). |
|               | 2)                | PRZM Scenario Guidance (EPA,    |
|               |                   | 2004).                          |
|               | 2.0 cm (HORIZN =  |                                 |
|               | 3)                |                                 |
+---------------+-------------------+---------------------------------+
| Field         | 0.17 cm^3^/cm^3^  | NRCS Soil Data Mart (SDM);      |
| Capacity      | (HORIZN =1)       | values are mean 1/3-bar water   |
| (THEFC)       |                   | contents of Biscayne marl,      |
|               | 0.17 cm^3^/cm^3^  | drained soils.                  |
|               | (HORIZN =2)       |                                 |
|               |                   |                                 |
|               | 0.17 cm^3^/cm^3^  |                                 |
|               | (HORIZN =3)       |                                 |
+---------------+-------------------+---------------------------------+
| Wilting Point | 0.1 cm^3^/cm^3^   | NRCS Soil Data Mart (SDM);      |
| (THEWP)       | (HORIZN =1)       | values are mean 15-bar water    |
|               |                   | contents of Biscayne marl,      |
|               | 0.1 cm^3^/cm^3^   | drained soils.                  |
|               | (HORIZN =2)       |                                 |
|               |                   |                                 |
|               | 0.1 cm^3^/cm^3^   |                                 |
|               | (HORIZN =3)       |                                 |
+---------------+-------------------+---------------------------------+
| Organic       | 2.61 % (HORIZN =  | NRCS SDM; values for horizons 1 |
| Carbon        | 1)                | to 3 = mean %OM / 1.724. PRZM   |
| Content (OC)  |                   | Scenario Guidance (EPA, 2004).  |
|               | 2.61 % (HORIZN =  |                                 |
|               | 2)                |                                 |
|               |                   |                                 |
|               | 1.16 % (HORIZN =  |                                 |
|               | 3)                |                                 |
+---------------+-------------------+---------------------------------+

[]{.mark}

[]{.mark}

***Sensitive Parameter Uncertainties***

[Meteorological File]{.underline}

As characterized above, Metfile W12839 (Miami, FL) is the closest
metfile to Dade County, which was used to represent this scenario. The
metfile is located approximately 20 miles from the center of Dade County
and is generally representative of southern Florida area.

[Slope]{.underline}

The scenario USLELS value was calculated with the Haan and Barfield
equation (1978) using a 1% slope and an assumed 400-foot slope length,
as per PRZM scenario development guidance (EPA, 2004). A slope of 1% was
selected because it is midpoint of the range for Biscayne soils
according to USDA (USDA 2006b). This scenario may underestimate runoff
for nurseries located on slopes greater than 1%

[USLE C Factor and Manning's N Value]{.underline}

The RUSLE Project does not include data for ornamental nursery crops.
Therefore, USLE C Factor and Manning's N values were selected from data
on Florida Strawberry with no till due to the similarities between
conditions. Approximately 80% of Florida's nursery operations are
containerized (University of Florida, 2000) therefore a no till RUSLE
file was chosen. Of the available locations, Tampa Florida has the most
similar meteorological conditions, no till, and light and cover as this
scenario.

[Soil Data]{.underline}

No geospatial data were available to determine the exact locations and
geographic extent of nurseries in the region. The USGS GIRAS
Landuse/Landcover data for the Conterminous United States includes a
nurseries classification; however the data are generally 25 years old at
the time of this scenario development and preliminary review of the data
indicates that nurseries are not well represented. This is likely due to
the resolution of the data (30 m) and age of the data set (based on
1970's and 80's imagery). As a result, soils were selected based on soil
recommendations on information from Garofalo (2002), the geographic
extent of the listed soils in the area, the drainage group, slope, and
erodibility. The soil selected is a hydrologic group D soil.

[Crop Parameters]{.underline}

Outdoor ornamental nurseries are highly diverse in the numbers, sizes,
and types of plants grown. Ornamental nurseries also vary in the
cultivation methods which can range from potted plants (container
operations) to field nurseries that may harvest and package plants as
bare root or balled and burlapped. This scenario has been parameterized
to be representative of the most "typical" nursery plants in the area
(see description above). Runoff and erosion may be over or
underestimated depending on the type of nursery modeled and a
sensitivity analysis has high value in this regard.

[Curve Number]{.underline}

The curve number is the most sensitive parameter in PRZM scenarios. The
curve number for this scenario was based on TR-55 (Table 2-2c).
Nurseries can be covered in roads, wooded areas, field borders, and
buildings. Therefore the curve number closest to this scenario was the
value for a hydrologic group D soil representative of farmsteads,
buildings, lanes, driveways, and surrounding lots. Runoff and erosion
may be under or over-estimated for alternative nursery operations and
model validation has high value in this regard. Based on preliminary
investigation, no runoff data are available for validating runoff from
outdoor nursery operations in this geographic area.

[]{.mark}

![](media/image1.png){width="9.375694444444445in"
height="5.472916666666666in"}

**Figure 1. TR-55 (USDA, 1986) Farmstead curve number used for scenario
development relative to other available cover types, soil treatments,
and conditions.**

[]{.mark}

<table style="width:100%;">
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<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 7%" />
<col style="width: 8%" />
</colgroup>
<tbody>
<tr class="odd">
<td colspan="11"><strong>Table 5. Soils of Dade County, FL Ranked by
Area <sup>a, b</sup></strong></td>
</tr>
<tr class="even">
<td><strong>Soil</strong></td>
<td><strong>Total Acres</strong></td>
<td><strong>% Area<sup>b</sup></strong></td>
<td><strong>Hydrologic Group</strong></td>
<td><strong>Erodibility</strong></td>
<td><strong>Slope</strong></td>
<td><strong>pH</strong></td>
<td><strong>OM</strong></td>
<td><strong>Sand</strong></td>
<td><strong>Silt</strong></td>
<td><strong>Clay</strong></td>
</tr>
<tr class="odd">
<td>Biscayne</td>
<td>80540</td>
<td>17.4%</td>
<td>B/D</td>
<td>0.32</td>
<td>0 - 1.9</td>
<td>7.9</td>
<td>4-4.5</td>
<td>10</td>
<td>77</td>
<td>13</td>
</tr>
<tr class="even">
<td>Udorthents</td>
<td>62050</td>
<td>13.4%</td>
<td>A</td>
<td>0.02-0.1</td>
<td>0-60</td>
<td>7.9</td>
<td>0.5</td>
<td>40-93</td>
<td>4.5-40</td>
<td>2.5-20</td>
</tr>
<tr class="odd">
<td>Krome</td>
<td>58620</td>
<td>12.7%</td>
<td>A</td>
<td>0.20</td>
<td>0 - 2</td>
<td>7.9</td>
<td>6.5</td>
<td>43</td>
<td>39.5</td>
<td>17.5</td>
</tr>
<tr class="even">
<td>Perrine</td>
<td>53440</td>
<td>11.6%</td>
<td>D</td>
<td>0.32</td>
<td>0 - 1</td>
<td>7.6-8.2</td>
<td>4-5</td>
<td>1-6</td>
<td>70.5-83</td>
<td>16-23.5</td>
</tr>
<tr class="odd">
<td>Lauderhill</td>
<td>45850</td>
<td>9.9%</td>
<td>B/D</td>
<td> </td>
<td>0 - 1.9</td>
<td> </td>
<td>75</td>
<td>0</td>
<td>0</td>
<td>0</td>
</tr>
<tr class="even">
<td>Dania</td>
<td>35330</td>
<td>7.6%</td>
<td>B/D</td>
<td> </td>
<td>0 - 1.9</td>
<td> </td>
<td>75</td>
<td>0</td>
<td>0</td>
<td>0</td>
</tr>
<tr class="odd">
<td>Vizcaya</td>
<td>29860</td>
<td>6.5%</td>
<td>D</td>
<td>0.10</td>
<td>0 - 2</td>
<td>7.2</td>
<td>25</td>
<td>20</td>
<td>60</td>
<td>20</td>
</tr>
<tr class="even">
<td>Chekika</td>
<td>26830</td>
<td>5.8%</td>
<td>D</td>
<td>0.37</td>
<td>0 - 2</td>
<td>7.9</td>
<td>6.5</td>
<td>40</td>
<td>42.5</td>
<td>17.5</td>
</tr>
<tr class="odd">
<td>Pahokee</td>
<td>20140</td>
<td>4.4%</td>
<td>B/D</td>
<td> </td>
<td>0 - 1</td>
<td> </td>
<td>82.5</td>
<td>0</td>
<td>0</td>
<td>0</td>
</tr>
<tr class="even">
<td>Pennsuco</td>
<td>13750</td>
<td>3.0%</td>
<td>D</td>
<td>0.32</td>
<td>0 - 1</td>
<td>8.2</td>
<td>4.5</td>
<td>1-3</td>
<td>79-80</td>
<td>17-20</td>
</tr>
<tr class="odd">
<td>Terra Ceia</td>
<td>8780</td>
<td>1.9%</td>
<td>D</td>
<td> </td>
<td>0 - 1</td>
<td> </td>
<td>72.5</td>
<td>0</td>
<td>0</td>
<td>0</td>
</tr>
<tr class="even">
<td>Hallandale</td>
<td>4690</td>
<td>1.0%</td>
<td>B/D</td>
<td>0.10</td>
<td>0 - 2</td>
<td>5.8</td>
<td>1.5</td>
<td>98</td>
<td>0.5</td>
<td>1.5</td>
</tr>
<tr class="odd">
<td>Opalocka</td>
<td>3780</td>
<td>0.8%</td>
<td>D</td>
<td>0.10</td>
<td>0 - 2</td>
<td>6.7</td>
<td>4.5</td>
<td>97</td>
<td>2</td>
<td>1</td>
</tr>
<tr class="even">
<td>Margate</td>
<td>3750</td>
<td>0.8%</td>
<td>B/D</td>
<td>0.10</td>
<td>0 - 2</td>
<td>5.3</td>
<td>2.5</td>
<td>97</td>
<td>0.5</td>
<td>2.5</td>
</tr>
<tr class="odd">
<td>Plantation</td>
<td>3410</td>
<td>0.7%</td>
<td>B/D</td>
<td> </td>
<td>0 - 1</td>
<td> </td>
<td>35</td>
<td>0</td>
<td>0</td>
<td>0</td>
</tr>
<tr class="even">
<td>Tamiami</td>
<td>3100</td>
<td>0.7%</td>
<td>D</td>
<td> </td>
<td>0 - 1.9</td>
<td> </td>
<td>70</td>
<td>0</td>
<td>0</td>
<td>3</td>
</tr>
<tr class="odd">
<td>Demory</td>
<td>2370</td>
<td>0.5%</td>
<td>D</td>
<td>0.10</td>
<td>0 - 2</td>
<td>6.7</td>
<td>12</td>
<td>70</td>
<td>6.5</td>
<td>23.5</td>
</tr>
<tr class="even">
<td>Cardsound</td>
<td>2260</td>
<td>0.5%</td>
<td>D</td>
<td>0.32</td>
<td>0 - 2</td>
<td>6.7</td>
<td>6.5</td>
<td>18.1</td>
<td>50.9</td>
<td>31</td>
</tr>
<tr class="odd">
<td>St. Augustine</td>
<td>1070</td>
<td>0.2%</td>
<td>C</td>
<td>0.10</td>
<td>0 - 2</td>
<td>7.3</td>
<td>2</td>
<td>97</td>
<td>2</td>
<td>1</td>
</tr>
<tr class="even">
<td>Matecumbe</td>
<td>780</td>
<td>0.2%</td>
<td>D</td>
<td> </td>
<td>0 - 2</td>
<td> </td>
<td>85</td>
<td>0</td>
<td>0</td>
<td>3</td>
</tr>
<tr class="odd">
<td>Dade</td>
<td>610</td>
<td>0.1%</td>
<td>A</td>
<td>0.10</td>
<td>0 - 2</td>
<td>7.3</td>
<td>2.5</td>
<td>98</td>
<td>1</td>
<td>1</td>
</tr>
<tr class="even">
<td>Pomello</td>
<td>520</td>
<td>0.1%</td>
<td>C</td>
<td>0.10</td>
<td>2 - 5</td>
<td>5.3</td>
<td>0.75</td>
<td>98</td>
<td>1</td>
<td>1</td>
</tr>
<tr class="odd">
<td>Kesson</td>
<td>490</td>
<td>0.1%</td>
<td>D</td>
<td> </td>
<td>0 - 0.9</td>
<td> </td>
<td>35</td>
<td>0</td>
<td>0</td>
<td>0</td>
</tr>
<tr class="even">
<td>Canaveral</td>
<td>310</td>
<td>0.1%</td>
<td>C</td>
<td>0.10</td>
<td>0 - 5</td>
<td>7.5</td>
<td>1</td>
<td>98</td>
<td>1</td>
<td>1</td>
</tr>
<tr class="odd">
<td>Basinger</td>
<td>230</td>
<td>&lt;0.1%</td>
<td>B/D</td>
<td>0.10</td>
<td>0 - 2</td>
<td>6</td>
<td>1.25</td>
<td>97</td>
<td>1</td>
<td>2</td>
</tr>
<tr class="even">
<td colspan="11"><p>Notes:</p>
<p><sup>a</sup> pH, OM, Sand, Silt, and Clay are based on representative
values from USDA Soil Data Mart.</p>
<p><sup>b</sup> Table excludes USDA Soil Data Mart areas for urban land,
beaches, water, and waters of the Atlantic ocean.</p></td>
</tr>
</tbody>
</table>

**Literature 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. Revised
2004.

Garofalo, J. 2002. The Nursery Industry in Miami-Dade County.
Publications for the horticultural professionals of Miami-Dade County,
Fact-sheet No. 58.

Garofalo, J., E.C. Worden, T. Frohne, and T. Stevens. 2002. Section 4:
The Commercial Ornamental Horticulture Industry in Miami-Dade County.
In: Degner, R.L., T.J. Stevens, and K.L. Morgan. Miami-Dade County
Agricultural Land Retention Study, Appendix A, Vol. 2. Fla. Agri. Market
Res. Center, IFAS, University of Florida, Gainesville, Fla. p. 110.

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.

Muñoz-Carpena, R., J.H. Crane, G.D. Israel, and J. Garofalo. 2003.
Ornamental growers\' water use and conservation practices in Miami-Dade
County, ABE347. Fla. Coop. Ext. Service, IFAS, Univ. of Fla.,
Gainesville, Fla. p. 4. Online at: <http://edis.ifas.ufl.edu/AE260>.

NOAA. 2006. Climate Normals at Major Weather Observing Stations in all
50 States, Puerto Rico, and Pacific Islands. National Oceanic and
Atmospheric Administration (NOAA), Environmental Satellite, Data, and
Information Service. Online at:
[http://www1.ncdc.noaa.gov/pub/data/ccd-data](http://www1.ncdc.noaa.gov/pub/data/ccd-data/).

UFLIAS. 2006. University of Florida Institute of Food and Agricultural
Sciences Extension Commercial Ornamentals Program for Miami-Dade County.
Online at: <http://miami-dade.ifas.ufl.edu/Programs/commorn.htm>.

University of Florida. 2000. Food and Resource Economics Department. A
Decade of Change in Florida\'s Ornamental Plant Nursery Industry, 1989
to 1999. Online at: hortbusiness.ifas.ufl.edu/EIR00-3.pdf

USDA. 1986. Urban Hydrology for Small Watersheds. United States
Department of Agriculture, Natural Resources Conversation Service.
Technical Release 55.

USDA. 1987. Official Soil Survey of Dade County, Florida. Online at:
<http://soils.usda.gov/survey/online_surveys/florida/dade/index.html>.
[]{.mark}

USDA. 2000A. Official Series Description -- TERRA CEIA Series. U.S.
Department of Agriculture, Natural Resources Conservation Service
(NRCS). October 2006. Online at:
<http://ortho.ftw.nrcs.usda.gov/osd/dat/T/TERRA_CEIA.html>

USDA. 2000B. 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 -- BISCAYNE Series. U.S.
Department of Agriculture, Natural Resources Conservation Service
(NRCS). October 2006. Online at:
<http://ortho.ftw.nrcs.usda.gov/cgi-bin/osd/osdname.cgi?-P>.

USDA. 2004a. Nursery Crops 2003 Summary. United States Department of
Agriculture National Agricultural Statistics Service. October. 2006.
Online at: [http://usda.mannlib.\
cornell.edu/usda/nass/NursProd//2000s/2004/NursProd-07-26-2004.txt](http://usda.mannlib.cornell.edu/usda/current/AgriChemUsNursFlo/AgriChemUsNursFlo-09-15-2004.txt).

USDA. 2004b. Agricultural Chemical Usage 2003 Nursery and Floriculture
Summary. United States Department of Agriculture National Agricultural
Statistics Service. October. 2006. Online at:
[http://usda.mannlib.cornell.edu/usda/current/AgriChemUsNursFlo/AgriChem\
UsNursFlo-09-15-2004.txt](http://usda.mannlib.cornell.edu/usda/current/AgriChemUsNursFlo/AgriChem%0BUsNursFlo-09-15-2004.txt).

USDA. 2006a. Soil Survey Areas of Dade County, Florida. U.S. Department
of Agriculture, Natural Resources Conservation Service (NRCS), Soil Data
Mart. October. 2, 2006. Online at:
[http://soildatamart.nrcs.usda.gov](http://soildatamart.nrcs.usda.gov/).

USDA. 2006b. Benchmark Soils of Florida. U.S. Department of Agriculture,
Natural Resources Conservation Service (NRCS). October 2006. Online at:
<http://ortho.ftw.nrcs.usda.gov/cgi-bin/osd/osdname.cgi?-P>.

**Contacts**

**Joe Garofalo, Ph.D.**

Commercial Ornamentals Agent\
University of Florida IFAS Extension

18710 SW 288 St.

Homestead, FL 33030 Phone: 305-248-3311

Email: <jgarofalo@ifas.ufl.edu>

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