Document ID: EPA-HQ-OPP-2005-0124-0072
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2007-05-02T04:00Z

SEQ CHAPTER \h \r 1 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C.  20460

									OFFICE OF

PREVENTION, PESTICIDES AND

TOXIC SUBSTANCES

MEMORANDUM

SUBJECT:	Assessment of Soil Fumigation with Chloropicrin, Methyl Bromide
and Metam-sodium in Strawberry Production

FROM: 	Leonard Yourman, Plant Pathologist

		Biological Analysis Branch

		Stephen Smearman, Economist

		Economic Analysis Branch

THRU:	Arnet Jones, Chief

		Biological Analysis Branch

		Biological and Economic Analysis Division (7503P)

Timothy Kiely, Chief

		Economic Analysis Branch

		Biological and Economic Analysis Division (7503P)

TO:		John Leahy, Senior Policy Advisor

		Special Review and Reregistration Division (7508P)

Summary

This document presents the assessment of the benefits provided by the
soil fumigants, particularly methyl bromide in the production of
strawberry fruit.  Methyl bromide mixed with chloropicrin has been the
leading chemical pre-plant soil treatment for commercial strawberries
grown in California and Florida, which produce over 90% of commercial
strawberries grown in the U.S.  As methyl bromide becomes less available
due to the worldwide phase-out process, farmers have turned to
1,3-dichloropropene (1,3-D) plus chloropicrin or metam-sodium for
pathogen (crown rot and black root rot) and nematode control.  Efficacy
of soil treatments vary depending on soil conditions.  Yields from 1,3-D
plus chloropicrin treated fields were 14% lower compared to yields when
methyl bromide was used in clay soils.  The estimated yield reduction
with use of metam-sodium was 30% compared to soils treated with methyl
bromide.  These estimates were based on responses from growers
estimating losses for the Methyl Bromide Critical Use Nomination program
(CUN, 2006; CUN, 2005).  Fumigant use in fresh fruit is primarily for
pathogen control and secondarily for regional nematode control.  

The total national net revenue benefits associated with the use of
methyl bromide for strawberry production are estimated to range from
$60.8 million for acres treated with 1,3-D plus chloropicrin to $203.2
million for acres treated with metam-sodium assuming all acres are
treated with either one or the other control.  

Introduction

As part of the reregistration process, EPA is assessing the risks and
benefits of the use of several soil fumigants: dazomet, chloropicrin,
metam-potassium, metam-sodium, and methyl bromide.  This document
presents the assessment of the benefits provided by the soil fumigants,
particularly methyl bromide and chloropicrin in the production of
strawberry fruit.  Conceptually, the benefits fumigants are the
improvements in production and/or reductions in cost resulting from
fumigant use.  The social benefits of any pesticide are divided between
the users of the pesticide, e.g., strawberry producers, and consumers of
strawberries and strawberry products.  Consumers benefit because higher
production and/or lower costs translate into a cheaper and more abundant
supply of strawberries.

Strawberry Fruit Production

According to the Economics Research Service, the United States is the
largest producer of strawberries in the world accounting for over 25% of
the world’s total production.  Other leading production areas include
the Russian Federation, Poland, Germany, Spain, Korea, Japan and Mexico.
   

California.  California produces more than 85% of fresh market and
processed strawberries grown in the U.S.  In terms of world-wide
production, California produces about 20% of the world’s strawberries
(ERS, 2005).  Most strawberries exported from California go to Canada,
Japan, and Mexico.  

California has two general strawberry production areas, northern and
southern, and five specific regions: Central Coast, Santa Maria, Oxnard
Plain, South Coast, and Interior Valley (Crop Profiles for Strawberry in
California, 1999).  Overall, the southern region produces both fresh
(63%) and processed (37%) strawberries.  The northern region includes
both rotated and non-rotated strawberry production regimes, with each
producing fresh (84%) and processed (16%) strawberries.  The average
strawberry farm is 47 acres (USDA-NASS, 2002) with strawberry fields in
rotation.  Because strawberry production in California is concentrated
in a small geographic location due to optimal growing conditions,
factors that affect this small area can be significant.  An example of
this is the regulatory limit on the amount of 1,3-dichloropropene
(1,3-D) that can be used in each township (i.e., 36 square mile area,
approximately 95 square km) in California (Trout, 2005).

Depending on the region, California strawberries are planted in the
summer (southern California) or fall (northern and southern California)
(CUN, 2006).  Prior to planting, fumigation is typically performed on
flat ground over the entire surface of the field.  Immediately after
fumigation the field is covered with plastic.  At the end of the
fumigation period, the plastic is removed and planting beds are formed
and covered with fresh plastic.  Strawberry plants are transplanted
about two to six weeks after fumigation to ensure that there are no
phytotoxic levels of fumigant remaining.  Harvest begins about two to
four months later.  At the end of the first harvest, the strawberry
plants are removed and the field is readied for the next crop. 
Rotational crops that are planted after strawberries, and that benefit
from the previous fumigation, include broccoli, celery, lettuce, radish,
leeks, and artichokes. 

Table 1.  Fresh Strawberry Acreage, Production and Value, Averaged from
2002–2004.

Region	Harvested Acres	Production

(1,000 cwt)	Yield

(cwt/acre)	Value

($ 1000)	Price

($/cwt)

California 	31,400	18,840	600	1,066,980	$56.60

Florida 	7,100	1,690	238	164,360	$97.50

U.S.	49,900	21,440	430	1,306,990	$61.00

Sources:  Crop Summary (USDA NASS, 2003-2006); Agricultural Prices (USDA
NASS, 2003-2006).

Florida.  Florida is the second largest strawberry producing state with
approximately 7% of the total U.S. production (ERS, 2005).  All of
Florida’s production is for fresh market primarily in the winter (Crop
Profiles for Strawberry in Florida, 2004).  The average strawberry farm
is 30 acres (USDA-NASS, 2002).  Strawberries are grown as an annual crop
in Florida using a raised-bed system.  Typically, MeBr in combination
with chloropicrin is applied to the soil during construction of
raised-beds, approximately two weeks prior to planting transplants. 
Immediately after application, beds are covered with plastic mulch. 
Drip and overhead irrigation are used to help establish plants, irrigate
plants, and protect plants from frost.  Many growers use the existing
beds and drip tubes to grow a follow-up crop after harvesting
strawberries, such as cucurbits or solanaceous crops.  Table 2 below
identifies the target pests for soil fumigants in strawberry fruit
production.

Table 2.  Target pests* for fumigants for strawberry fruit production.

State	Key Pests

California	Diseases: Black root rot (Rhizoctinia and Pythium spp.),
crown rot (Phytophthora cactorum); Nematodes: root knot nematode
(Meloidogyne spp.) Sting nematode (Belonolaimus spp.); Weeds: Yellow
nutsedge (Cyperus esculentus), purple nutsedge (Cyperus rotundus),
ryegrass, and winter annual weeds.  

Florida	Diseases: Crown rot, (Phytophthora citricola, P. cactorum);
Nematodes: Sting (Belonolaimus longicaudatus); Root-knot (Meloidogyne
spp.); Weeds: Yellow nutsedge (Cyperus esculentus); Purple nutsedge
(Cyperus rotundus); Carolina Geranium (G. carolinianum); Cut-leaf
Evening Primrose (Onoethera laciniata)

*Based on information supplied in critical use exemption requests for
methyl bromide submitted by strawberry consortia (CUN, 2006).

Application information for fumigants.

Application information for soil fumigants is listed below, which
discusses type of application, mixes, and ratios dependent upon the
situation.  This is followed by Tables 2-8, which illustrate soil
fumigant usage information by state, amount applied, number of acres
treated and the number of applications per season.  Most of these
fumigants are used with plastic films (tarps).  Film technology is
rapidly changing and numerous field experiments (e.g., Ajwa et al.,
2005; Fennimore et al., 2005; Gilreath et al., 2005; Johnson and
Fennimore, 2005) are being conducted to identify the films that can make
fumigants more effective.  Film permeability, heat retention, and
transmittance of certain wavelengths of light can affect the efficacy of
the fumigation process in terms of pest control. 

Methyl Bromide 

California.  Methyl bromide is shank injected 25-30 cm below the
surface.  It is generally broadcast (90%; 10% strip bed) and always
mixed with chloropicrin (currently at ratios ranging from 67:33 to
50:50, depending on the pest situation).

Florida.  Methyl bromide is shank injected 30-45 cm below the surface on
strip beds—fumigation is conducted on approximately 55% of the
acreage.  Methyl bromide is always used with chloropicrin (currently at
a ratio of 67:33).

Chloropicrin

California and Florida.   Chloropicrin is an important component of
preplant soil fumigation.  It is used in conjunction with methyl
bromide, and 1,3-D.  By itself, it can be an effective fungicide and at
high rates may be effective against weeds.  Chloropicrin followed by
metam-sodium may be effective pathogen and weed controls (UC-IPM, 2005).
 

1,3-Dichloropropene (1,3-D) + Chloropicrin 

California. Drip applied as InLine (1,3-D + 35% chloropicrin), this is
the primary alternative to methyl bromide (CUN, 2006).  It is sometimes
followed after 5-7 days by an application of metam-sodium to reduce weed
populations.  Generally, 1,3-D without chloropicrin is not effective for
strawberry production.  Township caps may restrict the use of 1,3-D. 
Approximately 35% of strawberry acreage in California is treated with
1,3-D + chloropicrin as an alternative to methyl bromide (CUN, 2006). 
According to the University of California (UC-IPM, 2005), 25% of
strawberry production land uses drip fumigation.  Drip fumigation is
applied to bed area only, which occupies approximately 50-70% of the
total area of an acre.  The recommended fumigant alternatives to methyl
bromide are 1,3-D + chloropicrin (InLine) followed by metam-sodium after
5-7 days or chloropicrin drip applied followed by metam-sodium after 5-7
days.

Florida.  Use of 1,3-D with 35% chloropicrin is typically shank injected
at a rate of 35 gal/acre (CUN, 2006).  It is applied 3-5 weeks ahead of
transplanting.  The fumigant application is supplemented with an
herbicide tank mix of oxyfluorfen (0.5 lb/A) plus napropamide (4
lb/acre) to the raised bed surface at tarp laying.  A minimum 30-day
interval is required before transplanting when using oxyfluorfen.  There
may be production delays due to increased time to reduce phytotoxic soil
residue after injection.  Use of 1,3-D + chloropicrin instead of methyl
bromide may result in an estimated 12% yield reduction (CUN, 2006), but
new tarp material may improve the situation with this alternative. 
Approximately 95% of strawberry production in Florida is within a
30-mile radius of Plant City (between Tampa and Lakeland) (CUN, 2006). 
Restrictions due to Karst topography may affect use of 1,3-D in many
locations in Florida.  Applications of drip applied 1,3-D require at
least two drip lines.

Metam-sodium (and other methyl isothiocyanate—MITC—producers).  

California.  California IPM (UC-IPM, 2005) recommends a metam-sodium
application following drip applied 1,3-D + chloropicrin (InLine) for
weed management.  Metam-sodium is not used as a stand alone fumigant in
strawberry production.

Florida. Metam-sodium is not considered an effective stand alone
treatment.  Follow-up applications after 1,3-D + chloropicrin have been
suggested for California farmers (UC-IPM, 2005) for weed management,
although it is unclear if this is an effective treatment for Florida
growers.  Restrictions on the use of 1,3-D or chloropicrin would limit
the usefulness of metam-sodium as a follow-up treatment.

Organic Production (no pesticides used on land within three years of
production)

As of 1999, organically grown strawberry production was less than 0.1%
of the total strawberry acreage in California (Crop Profiles for
Strawberries in California, 1999). Reports on production yields per acre
from organic fields range from 25% to 60% of the conventional yields,
although prices for produce may be higher than for conventional fruit.

Table 3.  Methyl bromide use information* for strawberry fruit
production.

State	Year	Acres Planted	% Acres Treated	No. Applications	A.I.** rate
per Application (lb/A)	A.I. rate per crop per Year (lb/A)	Total A.I.
(1000 lb/year)

Florida	2000	6,300	99	1.0	142	142	891

Florida	2002	6,900	100	1.0	134	134	918

Florida	2004	7,100	96	1.0	158	158	1084

*Source: National Agricultural Statistics Service (NASS).

  HYPERLINK
"http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2001/Agr
iChemUsVeg-07-15-2001.txt" 
http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2001/Agri
ChemUsVeg-07-15-2001.txt  (2000)

  HYPERLINK
"http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2003/Agr
iChemUsVeg-07-15-2003.txt" 
http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2003/Agri
ChemUsVeg-07-15-2003.txt  (2002)

  HYPERLINK
"http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2005/Agr
iChemUsVeg-07-15-2005.txt" 
http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2005/Agri
ChemUsVeg-07-15-2005.txt  (2004)

**Active ingredient.

Table 4.  Reported methyl bromide use in California* strawberry fruit
production.

Year	Planted Acres	No. Acres Treated	Total No. Applications	Total A.I.
**(1000 lb/year)

2000	27,600	22,580	1,562	4,226

2001	26,400	22,241	1,517	3,766

2002	28,500	20,501	1,319	3,702

2003	29,600	20,593	1,256	3,671

2004	33,200	18,467	1,191	3,187

2005	34,300	16,315	1,184	2,916

*Source: California Department of Pesticide Regulation (CDPR).

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur00rep/comrpt00.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur00rep/comrpt00.pdf  (2000)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur01rep/comrpt01.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur01rep/comrpt01.pdf  (2001)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur02rep/comrpt02.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur02rep/comrpt02.pdf  (2002)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur03rep/comrpt03.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur03rep/comrpt03.pdf  (2003)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur04rep/comrpt04.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur04rep/comrpt04.pdf  (2004)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur05rep/comrpt05.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur05rep/comrpt05.pdf  (2005)

**Active ingredient.

Table 5.  Chloropicrin use information* for strawberry fruit production.

State	Year	Planted Acres	% Acre Treated	No. Applications	A.I.** per
Application (lb/A)	A.I./Year (lb/A)	Total A.I. (1000 lb/year)

Florida	2000	6,300	95	1.0	68	68	408

Florida	2002	6,900	99	1.0	66	66	449

Florida	2004	7,100	70	1.0	65	65	323

*Source: National Agricultural Statistics Service (NASS).

  HYPERLINK
"http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2001/Agr
iChemUsVeg-07-15-2001.txt" 
http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2001/Agri
ChemUsVeg-07-15-2001.txt  (2000)

  HYPERLINK
"http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2003/Agr
iChemUsVeg-07-15-2003.txt" 
http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2003/Agri
ChemUsVeg-07-15-2003.txt  (2002)

  HYPERLINK
"http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2005/Agr
iChemUsVeg-07-15-2005.txt" 
http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2005/Agri
ChemUsVeg-07-15-2005.txt  (2004)

**Active ingredient.

Table 6.  Reported chloropicrin use in California* strawberry fruit
production.

Year	Planted Acres	No. Acres Treated	Total No. Applications	Total A.I.
**(1000 lb/year)

2000	27,600	22,855	1,620	2,358

2001	26,400	24,314	1,725	3,005

2002	28,500	24,187	1,568	2,910

2003	29,600	27,016	1,617	3,283

2004	33,200	28,241	1,614	3,258

2005	34,300	27,571	1,616	3,182

*Source: California Department of Pesticide Regulation (CDPR).

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur00rep/comrpt00.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur00rep/comrpt00.pdf  (2000)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur01rep/comrpt01.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur01rep/comrpt01.pdf  (2001)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur02rep/comrpt02.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur02rep/comrpt02.pdf  (2002)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur03rep/comrpt03.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur03rep/comrpt03.pdf  (2003)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur04rep/comrpt04.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur04rep/comrpt04.pdf  (2004)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur05rep/comrpt05.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur05rep/comrpt05.pdf  (2005)

**Active ingredient.

Table 7.  Dichloropropene (1,3-D) use information* for strawberry fruit
production.

States*	Year	Planted Acres	% Acre Treated	No. Applications	A.I.** per
Application (lb/A)	A.I./Year (lb/A)	Total A.I. (1000 lb/year)

California + Florida + Oregon	2000	38,000	NR***	NR***	NR***	NR***	NR***

	2002	38,900	6	1.1	165	184	428

	2004	43,600	8	1.2	168	196	715

*Source: National Agricultural Statistics Service (NASS). NASS only
reported usage information for 1,3-D as a combined use for California
(27,600 A planted), Florida (6,300 A planted), and Oregon (4,100 A
planted).

  HYPERLINK
"http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2001/Agr
iChemUsVeg-07-15-2001.txt" 
http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2001/Agri
ChemUsVeg-07-15-2001.txt  (2000)

  HYPERLINK
"http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2003/Agr
iChemUsVeg-07-15-2003.txt" 
http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2003/Agri
ChemUsVeg-07-15-2003.txt  (2002)

  HYPERLINK
"http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2005/Agr
iChemUsVeg-07-15-2005.txt" 
http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsVeg//2000s/2005/Agri
ChemUsVeg-07-15-2005.txt  (2004)

**Active ingredient.

***Not reported 

Table 8.  Reported dichloropropene (1,3-D) use in California* strawberry
fruit production.

Year	Planted Acres	No. Acres Treated	Total No. Applications	Total A.I.**
(1000 lb/year)

2000	27,600	143	30	13

2001	26,400	1,044	112	146

2002	28,500	2,473	202	440

2003	29,600	4,997	279	884

2004	33,200	9,109	392	1,522

2005	34,300	9,523	351	1,596

*Source: California Department of Pesticide Regulation (CDPR).

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur00rep/comrpt00.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur00rep/comrpt00.pdf  (2000)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur01rep/comrpt01.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur01rep/comrpt01.pdf  (2001)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur02rep/comrpt02.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur02rep/comrpt02.pdf  (2002)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur03rep/comrpt03.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur03rep/comrpt03.pdf  (2003)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur04rep/comrpt04.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur04rep/comrpt04.pdf  (2004)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur05rep/comrpt05.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur05rep/comrpt05.pdf  (2005)

**Active ingredient.

Table 9.  Reported metam-sodium use information for California*
strawberry fruit production.

Year	Planted Acres	No. Acres Treated	Total No. Applications	Total A.I.**
(1000 lb/year)

2000	27,600	314	41	63

2001	26,400	605	45	86

2002	28,500	1,370	61	238

2003	29,600	1,127	71	238

2004	33,200	1,741	92	274

2005	34,300	1,631	82	226

*Source: California Department of Pesticide Regulation (CDPR).

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur00rep/comrpt00.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur00rep/comrpt00.pdf  (2000)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur01rep/comrpt01.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur01rep/comrpt01.pdf  (2001)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur02rep/comrpt02.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur02rep/comrpt02.pdf  (2002)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur03rep/comrpt03.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur03rep/comrpt03.pdf  (2003)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur04rep/comrpt04.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur04rep/comrpt04.pdf  (2004)

  HYPERLINK "http://www.cdpr.ca.gov/docs/pur/pur05rep/comrpt05.pdf" 
http://www.cdpr.ca.gov/docs/pur/pur05rep/comrpt05.pdf  (2005)

**Active ingredients

Estimated Benefits of Fumigants

To determine the economic benefits of the fumigants, primarily methyl
bromide (MeBr), BEAD used a partial budget analysis to estimate the
changes in production costs on a typical acre for fresh fruit strawberry
crop grown.  This approach allows the Agency to compare changes to net
operating revenue.  Net revenue is calculated as gross revenue minus
operating costs.  This is a good measure of the direct changes in income
that may be realized by growers currently using fumigants for pest
control.  Net revenue does not represent net income to the users.  Net
income, which indicates profitability of an operation of an enterprise,
is gross revenue minus the sum of operating and fixed costs.  Net income
should be smaller than the net revenue measured in this study.  Fixed
costs were not included because they are often difficult to measure and
verify.

While this is a discussion of the benefits of all fumigants for fresh
strawberry producers, the primary fumigant used by producers in
California and Florida is MeBr.  Therefore the baseline established to
determine the benefits of all potential fumigants is based on using MeBr
and comparing the costs and revenues of growers who use MeBr to the
estimated changes in costs and revenues that may be realized using other
fumigants.

Per Acre Regional Benefits—California

In California, MeBr is the primary fumigant used by strawberry growers
with the 1,3-D plus chloropicrin as a second choice for many.  If
growers use an alternative other than MeBr, yield losses ranging from
14% to 30% are likely depending upon the alternative used.   If growers
choose 1,3-D plus chloropicrin to control pathogens and nematodes,
control costs are expected to increase from $1,549 to $1,979 per acre,
an increase of $430 per acre or 27.7%.  Net operating revenue is
expected to drop from the methyl bromide baseline of $3,632 to $1,311
per acre, a 64% decrease.  This is due to both yield losses and the
increase in control costs.  

For California growers using metam-sodium as a methyl bromide
replacement, control costs are expected to increase by approximately
$351 per acre or an increase of 22.6% and net operating revenue is
expected to decrease from $3,632 to a negative $6,391per acre, a loss of
$10,023 per acre or a -276% due to per acre yield losses and control
cost increases.  The benefits associated with the use of MeBr as the
baseline for California fresh fruit production are illustrated below in
Table 10. 

Total California Production losses are based on California Department of
Pesticide Regulation data for the 16,315 acres treated with methyl
bromide in 2005 (Table 4).  The estimated regional loss is estimated to
range from $37.8 million for 1,3-D plus chloropicrin to $163.5 million
for growers using metam-sodium.

Table 10.  Estimated Per Acre Gross Revenue, Operating Costs, and Net
Operating Revenue Impacts for California Strawberry Fruit Production

	Baseline

Methyl Bromide	Alternative

1,3-D + Pic	% Change	Alternative

Metam Sodium	% Change

Yield (pounds/acre)	36,638	31,509	-14.0	25,647	-30.0

Price  ($/lb)	.88	.88

.88

	Gross Revenue  ($/acre)	32,241	27,728	-14.0	22,569	-30.0

Methyl bromide

1,3-D + Pic ($/acre)

Metam-sodium  ($/acre)	1,549

	

1,979	

27.7	

1,900	

22.6

Other Operating Costs  ($/acre)	9,676	9,676

9,676

	Harvest Costs  ($/acre)	17,384	17,384

17,384

	Total Operating Costs  ($/acre)	28,609	29,039	1.5	28,960	1.2

Net Operating Revenue  ($/acre)	3,632	1,311	-64	-6,391	-276

Source:  USDA NASS (2006), 2006 Methyl Bromide Critical Use Nomination
for Preplant Soil Use on Strawberry, BEAD calculations.  Assumptions: 1:
fumigation costs include tarp and hand weeding costs; 2:Metam-sodium
fumigation costs derived from 2003 Doane, Farm Chemicals Handbook; yield
losses estimates from emergency exemption 03-FL-0024. Figures may not
sum due to rounding.

Per Acre Regional Benefits—Florida  

In Florida, methyl bromide is the primary fumigant used by strawberry
growers with the use of 1,3-D plus chloropicrin as a second choice for
many.  If growers choose an alternative other than MeBr, yield losses
are expected to range from 14% to 30% depending upon the alternative
used.  If growers choose 1,3-D plus chloropicrin to control pathogens
and nematodes, control costs are expected to decrease from $759 per acre
to $640 per acre, an decrease of $110 per acre or -14.6%.  This is due
to more fumigant control material being applied in California compared
to Florida.  Net operating revenue is expected to change from the MeBr
baseline of $9,045 to $5,569 per acre, a 37.4% decrease due to yield
losses.  For Florida growers using  methyl bromide rather than metam
sodium,, control costs are expected to increase by approximately $110
per acre, an decrease of 14.6%, and net operating revenue is expected to
decrease from $9,045 to $3,213 per acre, an decrease of $5,832 per acre,
or a decrease of 64.5% due to per acre yield losses.  

Total Florida production changes are based on USDA NASS 2004 data
estimates for the estimated 6,816 acres treated with methyl bromide
(Table 4).  The regional benefit assuming the value of methyl bromide as
the baseline is estimated to range from $23 million for 1,3-D plus
chloropicrin to $39.7 million for growers using metam-sodium.

The benefits associated with the use of MeBr as the baseline for Florida
fresh fruit production are illustrated below in Table 11.

Table 11.  Estimated Per Acre Gross Revenue, Operating Costs, and Net
Operating Revenue Impacts for Florida Strawberry Fruit Production

	Baseline

Methyl Bromide	Alternative

1,3-D + Pic	% Change	Metam-sodium	% Change

Yield (lb/acre)	2,042	1,748	-14	1,433	-30

Price  ($/12 lb flat)	13.20	13.20

13.20

	Gross Revenue  ($/acre)	26,954	23,073	-14	18,922	-30

Methyl bromide ($/acre)

1,3-D  ($/acre)

Metam-sodium  ($/acre)

	750	

640	

-14.6	

640	

-14.6

Other Operating Costs  ($/acre)	13,279	12,719	-4.2	11,743	-11.5

Harvest Costs  ($/acre)	3,880	4,055	4.5	3,326	-14.2

Total Operating Costs  ($/acre)	17,909	17,414	-2.7	15,709	-12.3

Net Operating Revenue  ($/acre)	9,045	5,659	-37.4	3,213	-64.5

Source: USDA NASS (2006), 2006 Methyl Bromide Critical Use Nomination
for Preplant Soil Use on Strawberry, BEAD calculations.  Assumptions: 1:
fumigation costs include tarp and hand weeding costs; 2:Metam-sodium
fumigation costs derived from 2003 Doane, Farm Chemicals Handbook; yield
losses estimates from emergency exemption 03-FL-0024. Figures may not
sum due to rounding.

 

National Benefits

Total national net revenue benefits associated with the use of fumigants
are estimated to range from $60.8 to 203.5 million for acres treated
with methyl bromide if growers choose MeBr rather than 1,3-D plus
chloropicrin or metam-sodium. 

Conclusion

The use of fumigants plays a very important role in fresh strawberry
production.  MeBr is the fumigant of choice in California and Florida
and the benefits of MeBr use are significant because of the relatively
lower material cost and more efficacious control, which reduces
additional inputs and produces higher yields and higher quality fresh
strawberries.    

REFERENCES

Ajwa, H. A., Fennimore, S., Browne, G., Martin, F., Trout, T., Duniway,
J., Shem-Tov, S., and Daugovish, O. 2005. Strawberry yield with various
rates of chloropicrin and Inline applied under VIF. Annual International
Research Conference on Methyl Bromide Alternatives and Emissions
Reductions, 2005.   HYPERLINK
"http://mbao.org/2005/05Proceedings/053AjwaH%20MBAO-ajwa05-VIF%20mta.pdf
" 
http://mbao.org/2005/05Proceedings/053AjwaH%20MBAO-ajwa05-VIF%20mta.pdf 

Crop Profiles for Strawberries in California. 1999.   HYPERLINK
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Crop Profiles for Strawberry in Florida. 2004.   HYPERLINK
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CUN (Critical Use Nomination for Methyl Bromide in Strawberry Fruit
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CUN (Critical Use Nomination for Methyl Bromide in Strawberry Fruit
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http://www.epa.gov/spdpublc/mbr/CUN2008/CUN2008_StrawberryFruit.pdf.

ERS (Economic Research Service)-USDA. 2005.  Fruit and Tree Nuts
Outlook.  July 28, 2005.   HYPERLINK
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Fennimore, S., Kabir, Z., Ajwa, H., Daugovish, O., and Roth, K. 2005.
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impermeable film. Annual International Research Conference on Methyl
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Johnson, M. S. and Fennimore, S. A. 2005. Weed and crop response to
colored plastic mulches in strawberry production.  HortScience
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Gilreath, J. P., Siham, M. N, Esmel, C. E., and Santos, B. M.2005b.
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Annual International Research Conference on Methyl Bromide Alternatives
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"http://www.mbao.org/2005/05Proceedings/016SihamM%20MBAO05abstract%20Myr
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Trout, T. 2005. Impact of township caps on telone use in California.
Annual International Research Conference on Methyl Bromide Alternatives
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http://www.mbao.org/2005/05Proceedings/127TroutT%20mb-pest-use-telone-rp
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UC-IPM (University of California). 2005. Strawberry drip fumigation.  
HYPERLINK "http://www.ipm.ucdavis.edu/PMG/r734900211.html" 
http://www.ipm.ucdavis.edu/PMG/r734900211.html 

USDA NASS (2002-2006)

USDA-NASS. 2002. The Census of Agriculture, 2002. Volume 1, Geographic
Area Series, Part 51.
http://www.nass.usda.gov/census/census02/volume1/us/USVolume104.pdf 

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