Document ID: EPA-HQ-OPP-2005-0123-0335
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 the Benefits of Soil Fumigation with
Chloropicrin, Methyl Bromide, and Metam-sodium in Tomato Production (DP
# 337490)

FROM:	Nikhil Mallampalli, Ph.D., Entomologist

Biological Analysis Branch

		Elisa Rim, Economist	

Economic Analysis Branch

Biological and Economic Analysis Division (7503P)

THRU:	Arnet Jones, Chief 	

Biological Analysis Branch

Timothy Kiely, Chief, 

Economic Analysis Branch

Biological and Economic Analysis Division (7503P)

TO:		John Leahy, Senior Policy Advisor

		Special Review and Reregistration Division (7508P)

BEAD Product Review Panel date: March 7, 2007

Summary

This document describes fumigant usage in tomato production, as well as
the benefits to tomato yields and grower revenues of the use of a group
of soil fumigants currently under registration review. The fumigants in
this group that are used on U.S. tomatoes include chloropicrin, metam
potassium, metam sodium, and methyl bromide. Of these, methyl bromide
and chloropicrin are the most widely used fumigants in fresh tomato
production, in terms of proportion of the national crop treated. In
processed tomatoes, metam-sodium and chloropicrin are the most widely
used fumigants. In this document, BEAD describes major pests targeted by
fumigants, relevant cultural practices, timing of fumigation and the
benefits of soil fumigation for tomato crops in three regions:
California, Michigan, and the southeastern U.S. Fumigant usage for all
USDA-surveyed states producing tomatoes is also presented. In
California, fumigation targets primarily fungi and nematodes; in
Michigan it targets mainly fungi, while in the southeastern U.S. target
pests include fungi, nematodes, and weeds such as nutsedges.

In total, about 70% of the U.S. fresh tomato crop is treated with one or
more fumigants. Fresh market tomato producers rely on fumigants for
disease, weed, and nematode control. In all regions with moderate to
severe pest pressure, the only technically and economically feasible
alternatives are other fumigants or fumigant combinations. The use of
fumigants improves yields by preventing losses from these pests, which
could potentially reduce fresh tomato production by as much as 66% in
terms of volume or 68% of the total value of production.  There are also
over 300,000 acres of processed market tomatoes grown in the U.S.
annually.  Approximately 20% of national processing tomato producing
acreage uses fumigants.  Losses from pests could potentially reduce
processing tomato production by as much as 19% in terms of volume or 18%
of the total value of production.  The total benefits of fumigation to
tomato acreage in California, Michigan, and the Southeastern U.S. could
be as much as $728 million.

Statement of Purpose

As part of the Registration Eligibility Decision (RED) process, EPA is
assessing the risks and benefits of the use of several soil fumigants as
a group:  chloropicrin, metam-potassium, metam-sodium, and methyl
bromide.  This document presents the assessment of the benefits to
tomato production that are provided by the soil fumigants, particularly
methyl bromide and chloropicrin, the most widely used of these
chemicals. Conceptually, the benefits of a pesticide like a soil
fumigant include improvements in production and/or reductions in cost
resulting from the pesticide use.  The social benefits of a pesticide
are divided between the users of the pesticide, e.g., tomato producers,
and consumers of tomato and tomato-containing products.  Consumers
benefit because higher production and/or lower costs translate into a
cheaper and more abundant supply of tomatoes. The impact of fumigant
regulation on this consumer benefit is not explicitly evaluated in this
document.

In evaluating the benefits of soil fumigants, this document compares the
current situation in which fumigants are available for use, subject to
existing label restrictions, to the situation that is estimated to occur
were the fumigants not available.  This is somewhat different from other
BEAD assessments of the impacts of regulation, in that no specific
regulatory scheme is considered.

General Background

This assessment focuses on fresh market tomatoes grown in Alabama,
Arkansas, California, Florida, Georgia, Indiana, Maryland,
Massachusetts, Michigan, New Jersey, New York, North Carolina, Ohio,
Pennsylvania, South Carolina, Tennessee, Texas, and Virginia.  Tomatoes
in these areas are grown in open fields on plastic tarps, often followed
by various other vegetable crops.  A more detailed discussion of key
fumigant usage, key target pests, and impacts of changes in fumigant
availability is presented for California, Michigan, and the southeastern
US as separate regions. 

These regions were selected for examination because (1) they are
representative of tomato cropping systems, pest occurrence, fumigant
use, etc. for western, north-central, and eastern production regions;
(2) some of  these regions produce large quantities of tomatoes and/or
treat large areas with fumigants; (3) growers from these areas submit to
EPA annual requests for methyl bromide under the critical use exemption
process of the Montreal Protocol, and have thus provided a database that
BEAD could draw upon.

The key fresh market tomato production areas as surveyed by the National
Agricultural Statistics Service (NASS) are described in Table 1 while
the processed market tomatoes are described in Table 2.  

Table 1.  Tomato Acreage Grown by State – Fresh Market,  2001 –
2005.

STATE	2001	2002	2003	2004	2005	Average

Alabama	         1,000 	         1,200 	         1,200 	         1,300 	
        1,200 	        1,180 

Arkansas	         1,400 	         1,300 	         1,300 	         1,400 
         1,200 	        1,320 

California	       38,000 	       36,000 	       34,000 	       42,500 	 
     43,600 	     38,820 

Florida	       44,500 	       43,200 	       43,300 	       42,400 	    
  45,200 	     43,720 

Georgia	         2,700 	         2,600 	         5,300 	         6,000 	
        6,500 	        4,620 

Indiana	         1,800 	         1,700 	         1,700 	         1,800 	
        1,700 	        1,740 

Maryland	         2,000 	         2,200 	         1,100 	         1,400 
 	        1,675 

Massachusetts	            450 	 	 	 	 	           450 

Michigan	         1,900 	         1,800 	         2,300 	         2,200 
         2,300 	        2,100 

New Jersey	         3,500 	         3,400 	         3,200 	        
3,000 	         3,000 	        3,220 

New York	         3,200 	         2,800 	         2,400 	         2,500 
         2,200 	        2,620 

North Carolina	         2,700 	         3,000 	         2,900 	        
2,700 	         2,700 	        2,800 

Ohio	         6,400 	         7,000 	         6,900 	         7,000 	   
     6,700 	        6,800 

Pennsylvania	         4,200 	         4,800 	         4,700 	        
4,200 	         3,900 	        4,360 

South Carolina	         3,300 	         3,300 	         3,400 	        
3,600 	         3,200 	        3,360 

Tennessee	         3,600 	         4,200 	         4,900 	         6,400
	         5,600 	        4,940 

Texas	         1,300 	         1,000 	         1,500 	         1,300 	  
      1,300 	        1,280 

Virginia	         4,000 	         3,900 	         5,500 	         5,700 
         5,700 	        4,960 

Other States 	            900 	 	 	 	 	           900 

US TOTAL	   126,850 	   123,400 	   125,600 	   135,400 	   136,000 	  
129,450 

Source: USDA/NASS Vegetable 2003 and 2005 Summary, January, 2004 and
2006.

Table 2.  Tomato Acreage Grown by State – Processed Market,  2001 –
2005.

STATE	2001	2002	2003	2004	2005	Average

California	     258,000 	     296,000 	     289,000 	     301,000 	    
267,000 	   282,200 

Indiana	         8,600 	         8,200 	         8,400 	         8,400 	
        8,300 	        8,380 

Michigan	         3,300 	         3,300 	         3,400 	         3,600 
 	        3,400 

Ohio	         6,370 	         6,400 	         6,400 	         6,600 	   
     6,200 	        6,394 

Other States 	         3,660 	         3,200 	         2,830 	        
1,630 	         4,440 	        3,152 

US TOTAL	   279,930 	   317,100 	   310,030 	   321,230 	   285,940 	  
302,846 

Source: USDA/NASS Vegetable 2003 and 2005 Summary, January, 2004 and
2006.

Average harvested acreage, annual production and values are provided in
Tables 3 and 4.  Tomatoes average almost $2 billion in total value per
year.  About 17% of production is for the fresh market which contributes
about 68% of the value.  Fresh market tomatoes command an average price
of $0.36 per pound while processed market tomatoes brings in only one
tenth as much.

  

Table 3. U.S. Fresh Market Tomato Production and Value of Production by
Region and State, 2001~2005 Average

Region and State	Harvested Acreage	Utilized Production	% of U.S.
Production	% of Regional Production	Value of Production

	(Acres)	(1,000 Cwt)	(%)	(%)	($1,000 dollars)

Western Region

California	    38,520 	          11,350 	31%	100%	$    357,742 

Regional Total	38,520	11,350	31%	100%	$    357,742

Southeastern Region

Alabama	1,120	305	1%	1%	$         8,680

Arkansas	1,240	314	1%	1%	$       13,020

Florida	42,900	14,747	40%	68%	$    573,458

Georgia	4,340	1,271	3%	6%	$       41,252

Maryland	1,525	196	1%	1%	$         8,556

North Carolina	2,520	808	2%	4%	$       22,923

South Carolina	3,220	878	2%	4%	$       23,678

Tennessee	4,520	1,172	3%	5%	$       39,156

Texas	1,140	159	0%	1%	$         7,202

Virginia	4,720	1,790	5%	8%	$       63,435

Regional Total	67,245	21,639	58%	100%	$       801,359

Midwestern Region

Indiana	1,620	255	1%	10%	$       17,161

Michigan	2,000	476	1%	19%	$       17,915

Ohio	6,500	1,766	5%	71%	$       67,076

Regional Total	10,120	2,497	7%	100%	$    102,152

Other States

Massachusetts 	400	56	0%	3%	$         5,600

New Jersey	3,160	689	2%	37%	$       26,741

New York	2,480	380	1%	20%	$       24,557

Pennsylvania	3,980	549	1%	29%	$       20,465

Other States	850	202	1%	11%	$       11,435

Regional Total	10,870	1,876	5%	100%	$         88,797

US TOTAL	125,450	37,116	100%

$ 1,334,710

Source: USDA/NASS Vegetable 2003 and 2005 Summary, January, 2004 and
2006.

Table 4. U.S. Processed Market Tomato Production and Value of Production
by Region and State, 2001~2005 Average

Region and State	Harvested Acreage	Utilized Production	% of U.S.
Production	% of Regional Production	Value of Production

	(Acres)	(Tons)	(%)	(%)	($1,000 dollars)

Western Region

California	272,800	10,044,028	94%	100%	$     579,227

Regional Total	272,800	10,044,028	94%	100%	$     579,227

Midwestern Region

Indiana	8,100	250,228	2%	47%	$       21,472

Michigan	3,275	112,825	1%	21%	$         9,231

Ohio	6,040	168,024	2%	32%	$       13,393

Regional Total	17,415	531,077	5%	100%	$         44,096

Other States

Other States	3,088	85,816	1%	100%	$         7,323

Regional Total	3,088	85,816	1%	100%	$         7,323

US TOTAL	292,648	10,638,356	100%

$     628,801

Source: USDA/NASS Vegetable 2003 and 2005 Summary, January, 2004 and
2006.

Use of Fumigants 

The following section provides a summary of our understanding of the use
of fumigants in tomato production.  In preparing this summary, we
referred to all available pesticide use data for the period 2001 to
2005.  These included data from the U.S. Department of Agriculture,
National Agricultural Statistics Service (NASS), The California
Department of Pesticide Regulation, Pesticide Use Reports (PUR),
information provided in methyl bromide critical use nomination packages,
and proprietary pesticide use data.  It is worth noting that these
sources are frequently divergent.  For this reason, we have reviewed
each of the sources carefully and have used what we concluded to be the
most appropriate and accurate information.  Thus, the data provided
below reflects an element of professional judgment.  It may therefore be
difficult to independently calculate the same estimates of fumigant use.
 Nonetheless, the information is intended to provide an indication of
the scale of regulatory impacts, not to calculate exact values of these
impacts.

As shown in Table 5, fresh market tomatoes are commonly fumigated with
chloropicrin, 1,3-dichloropropene, methyl bromide, metam sodium, or
metam potassium.  Over 10 million pounds of fumigants are used on
tomatoes per year in the U.S.  Metam potassium, metam sodium, and
1,3-dichloropropene each have less than 2% of the acres treated on
tomato acres. Methyl bromide is applied to approximately 35% of the
tomato acreage. Chloropicrin, which is often used in combination with
methyl bromide, metam-sodium, or dichloropropene, is applied to 30% of
the tomato crop.  In total, about 70% of the U.S. tomato crop is treated
with one or more fumigants. 

Table 5.  Fumigant Use on Fresh Tomatoes, 2001-2005 Average.

State	Active Ingredient	% Acres Treated1	Acres Treated	Pounds Applied

California	Chloropicrin	5%	2,000	154,100

	Dichloropropene	2%	700	58,200

	Metam Potassium	5%	1,600	335,000

	Metam Sodium	4%	2,100	160,200

	Methyl Bromide	3%	1,300	118,000

Florida	Chloropicrin	67%	29,700	1,780,000

	Dichloropropene	1%	500	82,000

	Methyl Bromide	91%	39,800	6,240,000

Georgia	Chloropicrin	44%	2,800	222,000

	Methyl Bromide	40%	2,600	373,000

Michigan	Chloropicrin	63%	1,300	125,000

	Methyl Bromide	65%	1,400	290,000

North Carolina	Chloropicrin	37%	1,000	55,000

	Methyl Bromide	37%	1,000	117,000

United States2	Chloropicrin	30%	39,100	2,585,000

	Dichloropropene	2%	2,400	220,000

	Methyl Bromide	35%	45,700	6,942,000

	Metam Sodium	1%	1,300	116,000

	Metam Potassium	1%	1,600	335,000

	US TOTAL	70%	90,100	10,198,000

Sources:  NASS Pesticide Use Reports (  HYPERLINK
"http://www.pestmanagement.info/nass/" 
http://www.pestmanagement.info/nass/ ), California PUR (  HYPERLINK
"http://www.cdpr.ca.gov/docs/pur/purmain.htm" 
http://www.cdpr.ca.gov/docs/pur/purmain.htm ), and EPA proprietary data.

Note that percent crop treated data and pounds applied were taken from
the above data sources.  Total area treated and pounds applied are
calculated from these.

Percent crop treated is calculated based on acres grown data from Table
1: California, 38,820; Florida, 43,980; Georgia, 6,500; Michigan, 2,100;
and North Carolina, 2,700, US Total: 129,450.

As shown in Table 6, processed market tomatoes are commonly fumigated
with 1,3-dichloropropene or metam sodium.  Almost 3 million pounds of
fumigants are used on processed tomatoes per year in the U.S. 
1,3-dichloropropene has less than 1% of the acres treated on tomato
acres. Metam sodium is applied to approximately 19% of the tomato
acreage.  In total, about 19% of the U.S. tomato crop is treated with
one or more fumigants. 

Table 6.  Fumigant Use on Processed Tomatoes, 2001-2005 Average.

State	Active Ingredient	% Acres Treated1	Acres Treated	Pounds Applied

California	Dichloropropene	0%	423	35,536

	Metam Sodium	20%	56,350	2,742,000

United States2	Dichloropropene  	1%	2,122	120,000

	Metam Sodium	19%	56,350	2,742,000

	US TOTAL	19%	58,472	2,862,000

Sources:  NASS Pesticide Use Reports (  HYPERLINK
"http://www.pestmanagement.info/nass/" 
http://www.pestmanagement.info/nass/ ), California PUR (  HYPERLINK
"http://www.cdpr.ca.gov/docs/pur/purmain.htm" 
http://www.cdpr.ca.gov/docs/pur/purmain.htm ), and EPA proprietary data.

Note that percent crop treated data and pounds applied were taken from
the above data sources.  Total area treated and pounds applied are
calculated from these.

Percent crop treated is calculated based on acres grown data from Table
1: California, 282,200; U.S., 302,846

FUMIGATION CHARACTERISTICS

Target Pests

Table 7 summarizes all major pests targeted by fumigation in the three
representative states, as reported by growers in their annual requests
for critical use exemptions (CUEs) for methyl bromide.

    Table 7. Key diseases, Pests, and weeds

Region 	Key diseases, Pests and weeds 

California	Soil borne diseases - Fusarium wilt, Verticillium wilt,
Pythium spp.

Root Knot nematodes (Meloidogyne spp.)

Michigan	Crown and root rots caused by soil-borne fungus Phytophthora
capsici. 

Southeastern US* 	Weeds: yellow & purple nutsedges (Cyperus rotundus &
C. esculentus), 

Plant diseases: Fusarium wilt, Phytophthora, Pythium spp.

Nematodes: root-knot nematodes (Meloidogyne spp.)

 * Southeastern U.S consists of: Alabama, Arkansas, Florida, Georgia,
Kentucky, Louisiana, Mississippi, North 

    Carolina, South Carolina, Tennessee, and Virginia.

Use Characteristics

Tables 8, 9, and 10 provide information describing typical fumigant use
in fresh tomato production.  This information was derived in part from
information submitted by tomato growers as part of the annual
nominations prepared by BEAD for methyl bromide Critical Use Exemptions
under the Montreal Protocol. 

Table 8.  Fumigant Application Information For Fresh Market Tomatoes
Grown In California.

Application Rate 

(lb ai/acre)1	Chloropicrin	75 to  133 pounds per acre

	1,3 - Dichloropropene	79 to  130 pounds per acre

	Metam Sodium	90 to  252 pounds per acre

	Metam Potassium	247 to  348 pounds per acre

	Methyl Bromide	112 to 316 pounds per acre

Acres Treated per Day	 10 to  40 acres per tractor

Time of Fumigation	 Dec – Apr or Oct - Dec

Application Method	Primarily shank injected under tarp

Strip Application	Primarily strip treated with 100% of area treated?

Tarps or Water Caps	HDPE tarp

1. Typical application rate range, based on California Department of
Pesticide Regulation, Pesticide Use Reporting,   HYPERLINK
"http://www.cdpr.ca.gov/docs/pur/purmain.htm" 
http://www.cdpr.ca.gov/docs/pur/purmain.htm .

Table 9.  Fumigant Application Information For Tomatoes Grown In
Michigan.

Application Rate

(lb ai/acre)	Chloropicrin	105 to 114 pounds per acre

	Methyl Bromide	160 to 230 pounds per acre

Acres Treated per Day 	10 to 40 acres per tractor

Time of Fumigation	April

Application Method	Shank injected under tarp

Strip Application 	Primarily strip with 58 % of area treated

Tarps or Water Caps	LDPE with some metalized film

Table 10.  Fumigant Application Information For Tomatoes Grown In
Southeastern US.

Application Rate

(lb ai/acre)	Chloropicrin	75 to  133 pounds per acre

	1,3 - Dichloropropene	79 to  130 pounds per acre

	Methyl Bromide	90 to  252 pounds per acre

Acres Treated per Day 	10 to 40 acres per tractor

Time of Fumigation	Southeastern US	Jan-Feb, or March-April, or June -
Sept 

	Georgia	July

	Florida	Aug – Sept (if double-cropped) or 

Aug – Jan (if not double cropped).  

Application Method	Shank injected under tarp

Strip Application	Primarily strip with 58 % of area treated

Tarps or Water Caps	LDPE with some HDPE and metalized tarps

Southeastern U.S consists of: Alabama, Arkansas, Florida, Georgia,
Kentucky, Louisiana, Mississippi, North Carolina, South Carolina,
Tennessee, and Virginia. 

Chemical Control Alternatives

In all these regions the chemical alternative to any given fumigant
would probably be another fumigant combination.  

Cultural Control Practices

Currently, cultural control practices have not provided technically or
economically effective control of the key pest problems.  Many of the
pests are long lived and crop rotation out of any host crops for several
years is not an economic alternative. A totally organic production
system would not be feasible for areas with moderate to high pest
pressure.  In 2005 only 4.6% of the U.S. vegetable production was grown
organically (USDA ERS 2006).  

For regions where Phytophthora capsici is a key pest, crop rotations are
virtually ineffective because the pathogen can survive for several years
in the soil, and can infect more than 50 plant species. Reservoirs for
re-infection are thus difficult to eradicate. 

BENEFITS OF FUMIGATION

The subsections below describe studies used by BEAD to explore possible
yield losses due to key pests in specific regions. Table 11 summarizes
the range of yield losses BEAD believes are plausible for tomatoes in
each region. In all regions, a situation where the growers are able to
switch from the most widely used fumigant regime to the next best
available fumigant/herbicide combination constitutes the lower bound of
yield losses estimates. The upper bound of yield loss estimates was
derived from the results from studies where a ‘no fumigation’
treatment was included. The next best fumigant regime varies for each
region and is described in each subsection below.

California

BEAD has been unable to locate research done in tomatoes in this region,
on comparative efficacy of alternatives to methyl bromide + chloropicrin
or metam-sodium (the dominant fumigants of fresh and processed tomatoes,
respectively, in this region). However, the pests targeted are similar
to those listed for southeastern US tomatoes (Table 7), a notable
exception being nutsedges, which are apparently not major pests in
California. Therefore, BEAD used estimates of yield losses derived from
selected studies done in Florida and other southeastern states to
analyze economic impacts of fumigant loss. For a discussion of these
studies and a summary of yield loss estimates, please see the section
for the southeastern US below, as well as Table 11.

In California, growers denied the use of the dominant fumigant regime in
fresh tomatoes, methyl bromide + chloropicrin, are presumed to turn to
metam-sodium + chloropicrin as the next best fumigant regime. Processed
tomato growers are likely to switch from metam-sodium + chloropicrin
(the standard fumigant regime) to 1,3 D + chloropicrin. It is not clear
to what extent this switch is feasible, because California limits the
use of 1,3 D using township-level caps on amounts used. It is unlikely
that processed tomato growers would use methyl bromide in place of
metam-sodium, as the costs of using this material along with the
required plastic tarps is economically infeasible. This infeasibility is
illustrated further in the economic analysis below.

Michigan

Research by Hausbeck in 2006 on Phytophthora root rot tested foliar
applied fungicides on solanaceous and cucurbit crops. Results indicated
that one of the best treatments was mefenoxam, but even with this option
there was a 20 % yield loss. 1,3 D is not a feasible option in this
region because of low soil temperatures typical during the time of
season that fumigation is needed. In the event of a loss of the standard
fumigation strategy (methyl bromide + chloropicrin), most growers would
probably turn to metam-sodium + chloropicrin. If no chemical fumigants
were available, growers would probably try to use the best available
fungicide, mefenoxam, despite the yield losses associated with it.

Southeastern US 

Yield losses of 6 to 64% are estimated when fumigation is converted from
methyl bromide to the best available alternative fumigant combination. 
If a fumigant combination were not available due to regulatory
constraint the losses would be greater (see Table 11).   

In research conducted in Florida (Motis et al 2003) Relative to yields
with no nutsedge, pepper fruit yields in each season were reduced 10%
with fewer than 5 planted tubers/m2. While this research was not
conducted on tomatoes specifically, the results are from a closely
related (Solanaceous) vegetable crop with a similar life history and
pest vulnerability. Yield losses increased more rapidly with an increase
in initial nutsedge density from 0 to 30 than from 30 to 120 tubers/m2.
With 30 nutsedge tubers/m2, large fruit yield was reduced 54 to 74%
compared to that with no nutsedge.  Nutsedge shoots overtopped the
pepper plants as early as 6 wk after treatment when, with 15 planted
tubers/m2, nutsedge interference reduced pepper plant biomass by 10 to
47%. Taken together, these data indicate losses possible if no
fumigation or other effective controls are applied for severe nutsedge
infestations.

In southeastern tomatoes, combinations of fungal pathogens, nematodes,
and nutsedge weeds have also been studied with the goal of quantifying
efficacy of methyl bromide alternatives. Some of these studies also
included untreated controls, which provide some measure of the impact of
these pests in situations where no fumigation occurs. For example,
Santos et al. (2006) used sites with a history of heavy infestations of
Fusarium, nematodes, and nutsedges. In untreated plots, yield losses
(relative to a methyl bromide standard) over 2 years of sampling ranged
from 41.9 % to 91.4 %. In plots treated with 1,3 D + chloropicrin, 0 to
4 % yield losses were observed.

Studies done in southeastern tomatoes using only Fusarium or root knot
nematodes have also been performed. The results of such studies provide
some measure of the impact of these pests without the presence of
nutsedges, and may be used to infer an estimate of the impact of the
pest complex on California tomato production (where nutsedges are not a
major concern). 

McGovern et al. (1998) compared the efficacy of methyl bromide +
chloropicrin and metam-sodium where Fusarium spp. were the pest present.
Trials were performed in small plots in fields in commercial Florida
farms. Compared to methyl bromide, the use of metam sodium gave yield
losses of 2.8 to 20 %. In untreated plots, losses due to Fusarium ranged
from 9.9 to 42.9 %.

In a study that illustrated the impact of root knot nematodes on
tomatoes, Noling and Gilreath (2004) compared the efficacy of methyl
bromide + chloropicrin with that of 1,3 D + chloropicrin. In this
small-plot study, losses due to nematodes in untreated fields ranged
from 30.6 to 57.8 % (relative to yields in the methyl bromide
treatment). Yields in the 1,3 D treatment ranged from a  7.6 % loss to a
7.1 % gain. 

In the southeastern US, tomato growers who lose methyl bromide +
chloropicrin (the dominant fumigation regime) would probably turn to
either a combination of 1,3 D, chloropicrin, and herbicides, or (in
areas where 1,3 D is prohibited due to soil types present) metam-sodium
+ chloropicrin. Losses in either case would be about 6 %, based on the
studies summarized above and in Table 11. If no fumigation were
possible, losses in untreated fields could be as high as 64 % (Table
11).

Table  11.  tomato Yield Loss Data  

Alternative	Type of Pest Tested 	Range of Yield Loss (%)	Best Estimate
of Yield Loss (%)

1,3 dichloropropene + chloropicrin (with or without additional
herbicides and additional chloropicrin)	Nutsedges, fungal pathogens,
nematodes; southeastern US

 (McGovern et al. 1998; Noling and Gilreath 2004; Santos et al. 2006)	0
– 13 	6 

Metam-sodium (with or without chloropicrin)	Nutsedges, fungal pathogens,
nematodes;

southeastern US (McGovern et al. 1998; Noling and Gilreath 2004; Santos
et al. 2006)	0-15 	7

No fumigation	Nutsedge in southeastern US (Motis et al. 2003)	54 to 74
64 

No fumigation but with mefenoxam fungicide	Phytophthora root rot in
Michigan (Hausbeck 2006)	5 to 42 

20% with mefenoxam	5 to 20

No fumigation	Combination of fungal, nematode and weed pests in
southeastern US (Santos et al.2006)	41 – 91	64 

Overall Loss Estimate for All Alternatives to Pests	California 5 to 64 %

Michigan 7 to 20%

Southeast 6 to 64 %

Economic Impacts

In the following section we evaluate the impact of estimated tomato
yield losses on the economic viability of tomato producers.  BEAD uses a
partial budget analysis to estimate the impacts of changes in
production.  That is, we evaluate the consequences on a typical acre of
the crop grown, rather than attempt to assess the impacts in the context
of a whole enterprise, which could include multiple crops under
cultivation.  This approach allows the Agency to compare losses to net
operating revenue, which is defined as the difference between gross
revenue and variable operating costs, on a per-acre basis.  The analysis
ignores fixed costs, which are highly dependent on land ownership and
the size and diversity of the grower’s operation, and therefore
difficult to define on a per-acre basis.  As such, this analysis may
understate the impacts as a percentage of the grower’s income.  

Estimated impacts of fumigant regulation in California, Michigan, and
Southeastern U.S. tomato production are summarized in Tables 12, 13, 14,
and 15.  

California

Table 12.  Economic Analysis California Tomato, Fresh Market.

	Methyl Bromide + chloropicrin	Metam Sodium

+ chloropicrin	No Fumigation

Estimated Yield Loss	0%	7%	64%

Yield (CWT)	295	274	106

Price  per CWT	$31	$31	$31

Gross Revenue  	$9,222	$8,576	$3,320

Non-Fumigant alternatives cost	$0	$0	$50

Land Preparation and Growing Period Costs  ($/acre)	$6,736	$7,226	$7,276

Harvest Costs  	$917	$853	$330

Total Operating Costs  	$8,800	$8,747	$7,606

Net Operating Revenue  	$421	($171)	($4,286)

Percentage Change in Net Operating Revenue	0%	-141%	-1117%

Source:  California Methyl Bromide Critical Use Nomination, 2004. 

Includes the cost of fumigant and labor.

Without the use of metam sodium or chloropicrin, California tomato
producers would not be able to sustain the losses presented in Table 12.
 This would apply to that part of the California tomato acreage that is
treated with one or more fumigants, or about 20% or 7,700 acres (Table
5).  Halted tomato production on these acres would represent a loss of
about $72 million and over 2 million CWT of tomato production annually
(Table 3).  Given that tomato acreage can be put to a different use,
such as producing a different crop, these losses would ultimately be
somewhat less.

Table 13.  Economic Analysis California Tomato, Processed Market.

	Metam Sodium

+ chloropicrin	1,3 dichloropropene + chloropicrin +	No Fumigation

Estimated Yield Loss	0%	6%	64%

Yield (Tons)	37	35	13

Price per Ton	$58	$58	$58

Gross Revenue  	 $2,120 	 $1,993	 $763

Non-Fumigant alternatives cost	$0	$0	$50

Total Operating Costs  	$1,159	$1,159	$1,209

Net Operating Revenue  	$961	$833	($446)

Percentage Change in Net Operating Revenue	0%	-13%	-146%

Source:  Sample Costs to Produce Processing Tomatoes: San-Joaquin
Valley, Double-Row Seeded. University of California Cooperative
Extension. Available at:   HYPERLINK
"http://coststudies.ucdavis.edu/outreach/cost_return_articles/2001toms.p
df" 
http://coststudies.ucdavis.edu/outreach/cost_return_articles/2001toms.pd
f 

Without the use of metam sodium or chloropicrin, California processing
tomato producers would not be able to sustain the losses presented in
Table 13.  This would apply to that part of the California processing
tomato acreage that is treated with one or more fumigants, or about 20%
or 11,270 acres (Table 6).  Halted tomato production on these acres
would represent a loss of about $116 million and over 2 million tons of
processed tomato production annually (Table 4).  Given that tomato
acreage can be put to a different use, such as producing a different
crop, these losses would ultimately be somewhat less.

Michigan

Table 14.  Economic Analysis  Michigan Tomato, Fresh Market.

	Methyl Bromide + chloropicrin	Metam Sodium	No Fumigation

Estimated Yield Loss	0%	7%	20%

Yield (CWT)	236	219	189

Price  per CWT1	$37	$31	$31

Gross Revenue  	$8,708	$6,803	$5,852

Fumigation costs to control soil borne disease 	$369	$438	$0

Non-Fumigant alternatives cost	$0	$0	$50

Land Preparation and Growing Period Costs  ($/acre)	$3,349	$3,563	$3,563

Harvest Costs  ($/acre)	$1,053	$979	$842

Total Operating Costs  ($/acre)	$4,771	$4,980	$4,455

Net Operating Revenue  ($/acre)	$3,938	$1,823	$1,397

Percentage Change in Net Operating Revenue	0%	-54%	-65%

Source:  Michigan Methyl Bromide Critical Use Nomination, 2006.

Alternatives to Methyl Bromide include a 16% Price adjustment due to
missed market windows.

Without the use of methyl bromide and chloropicrin, Michigan tomato
producers would not be able to sustain the losses presented in Table 14.
 Because 63-65% of Michigan tomato acreage is fumigated (over 1,300
acres out of 2,100 acres) this conclusion applies to most Michigan
tomato production (Table 5).  Halted tomato production on these acres
would represent a loss of about $12 million and 309 thousand CWT of
tomato production annually (Table 2).  Given that tomato acreage can be
put to a different use, such as producing a different crop, these losses
would ultimately be somewhat less.

Southeastern U.S.

For this region, the economic analysis presented below used Florida
statistics as representative of tomato production. Florida is arguably
the largest producer within this region, and is typical of the region in
terms of pest spectrum.

Table 15.  Economic Analysis Florida Tomato, Fresh Market.

	Methyl Bromide + chloropicrin	1,3 dichloropropene + chloropicrin +	No
fumigation

Estimated Yield Loss	0%	6%	64%

Yield (CWT)	344	323	124

Price per CWT	$38	$38	$38

Gross Revenue  	$13,210	$12,417	$4,755

Fumigation Costs, Weeds and Soil Borne Disease	$561	$561	$0

Land Preparation and Growing Period Costs  ($/acre)	$3,906	$3,906	$3,906

Harvest Costs  	$4,936	$4,640	$1,777

Total Operating Costs  	$9,403	$9,107	$5,683

Net Operating Revenue  	$3,807	$3,310	 ($927)

Percentage Change in Net Operating Revenue	0%	-13%	-124%

Source:  Southeast U.S. Methyl Bromide Critical Use Nomination, 2006.

Without the use of methyl bromide and chloropicrin, Florida and other
southeastern U.S. tomato producers would not be able to sustain the
losses presented in Table 15.  This would apply to that part of the
southeastern tomato acreage that is treated with one or more fumigants. 
An upper bound of this impact is provided by the 91% of Florida acreage
treated with methyl bromide (Table 5), which equates to about 40,000
acres. Halted tomato production on these acres would represent a loss of
nearly $528 million and 13 million CWT of tomato production annually
(Table 3).  Given that tomato acreage can be put to a different use,
such as producing a different crop, these losses could ultimately be
somewhat lower than this upper bound.

National Impacts

There are over 129,000 acres of fresh market tomatoes grown in the U.S.
annually.  If fumigants are no longer available to fresh market tomato
producers who currently rely on them for disease, weed and nematode
control, given the magnitude of expected yield losses, U.S. tomato
production would be severely impacted.  Approximately 70% of tomato
producing acres would be impacted, potentially reducing tomato
production by 66% by volume or 68% of the total value of production. 
Again, tomato acreage could be put to a different use, such as producing
a different crop; these losses could be somewhat less on a national
scale as well.

There are also over 300,000 acres of processed market tomatoes grown in
the U.S. annually.  If fumigants are no longer available to processed
market tomato producers who currently rely on them for disease, weed and
nematode control, given the magnitude of expected yield losses, U.S.
tomato production would be severely impacted.  Approximately 20% of
tomato producing acres would be impacted, potentially reducing tomato
production by 19% by volume or 18% of the total value of production. 
Again, tomato acreage could be put to a different use, such as producing
a different crop; these losses could be somewhat less on a national
scale as well.

CONCLUSIONs

Of the soil fumigants currently being reviewed by EPA, chloropicrin,
methyl bromide, and metam sodium are all used on tomatoes in the west
(represented by California), Midwest (represented by Michigan), and the
southeast U.S.  Soil pathogens are a driving factor all regions, along
with nematodes in the west and southeast, plus weeds in the southeast. 
In all regions with moderate to severe pest pressure, the only
technically and economically feasible alternatives are other fumigants
or fumigant combinations.  Yield losses can range from 5 to 64% in
California, 7 to 20 % in Michigan, and 6 to 64% in the southeast.  In
total, about 70% of the U.S. fresh tomato crop, and about 20% of the
processed tomato acres, is treated with one or more fumigants. Fresh
market tomato producers rely on fumigants for disease, weed, and
nematode control. In all regions with moderate to severe pest pressure,
the only technically and economically feasible alternatives are other
fumigants or fumigant combinations. The use of fumigants improves yields
by preventing losses from these pests, which could potentially reduce
fresh tomato production by as much as 66% in terms of volume or 68% of
the total value of production.  There are also over 300,000 acres of
processed market tomatoes grown in the U.S. annually.  Losses from pests
could potentially reduce processing tomato production by as much as 19%
in terms of volume or 18% of the total value of production.  The total
benefits of fumigation to tomato acreage in California, Michigan, and
the Southeastern U.S. could be as much as $728 million.

Limitations to this assessment

This document presents the assessment of the benefits provided by the
soil fumigants in the production of tomatoes.  The following are
limitations of this analysis:

Social benefits of pesticide use accrue to several groups, e.g., tomato
producers and consumers of tomatoes.  This document considers the
benefits of fumigant use from the perspective of tomato producers and
does not account for economic impacts on other parties.

The assessment does not account for transition to new agronomic
practices such as a conversion to greenhouse production, introduction of
new growing areas, or the introduction of newer as yet unregistered
fumigants.  

The assessment is based on partial budget analysis and does not account
for price or income distribution effects resulting from changes in
supply. 

REFERENCES

California Pepper Commission.  2005  Yield loss due to Phytophthora
capsici root rot, Red Bell Pepper Yield Loss, Deardorff Jackson Farms,
Ventura CA. 2005.  Letter in support of 2009 California Critical Use
Exemption Request for Peppers. 

Hausbeck, M. and B. Cortright.  2004.  Comparing Fumigants for the 
Control of Control of Phytophthora capsici in Vegetable Crops in
Vegetable Crops.  Methyl Bromide Alternatives Outreach presentation in
2004.  Available at:
http://www.mbao.org/2004/PowP/039Cortright%20%2039.pdf

Hausbeck, M.  2006.  Vegetable Crop Advisory Team Alert newsletter. 
Vol. 21, No. 13, July 19, 2006.  Available at:   HYPERLINK
"http://ipm.msu.edu/cat06veg/v07-19-06.htm#3" 
http://ipm.msu.edu/cat06veg/v07-19-06.htm#3  

McGovern, R.J., C.S. Vavrina, J.W. Noling, L.A. Datnoff, and H.D. Yonce.
1998. Evaluation of application methods of metam sodium for management
of Fusarium crown and root rot in tomato in southwest Florida. Plant
Disease 82: 919-923.

May, D. M., B.L. Weir, J. J. Nunez, K. M. Klonsky, R. L. De Moura. 2001.
Sample Costs to Produce Processing Tomatoes: San-Joaquin Valley,
Double-Row Seeded. University of California Cooperative Extension.
Available at:   HYPERLINK
"http://coststudies.ucdavis.edu/outreach/cost_return_articles/2001toms.p
df" 
http://coststudies.ucdavis.edu/outreach/cost_return_articles/2001toms.pd
f 

Motis, T. N., S. J. Locasio, J. P. Gilreath, and W. M. Stall.  2003. 
Season-Long Interference of Yellow Nutsedge (Cyperus esculentus) with
Polyethylene-Mulched Bell Pepper (Capsicum annuum).  Weed Technology.
Volume 17:543–549

Noling, J.W. and J.P. Gilreath. 2004. Evaluations of chemical
alternatives to methyl bromide for nematode control and tomato yield in
field microplots. Methyl Bromide Alternatives Outreach presentation in
2004.  Available at:   HYPERLINK "http://www.mbao.org" 
http://www.mbao.org .

Santos, B.M., J.P. Gilreath, T.N. Motis, J.W. Noling, J.P. Jones, and
J.A. Norton. 2006. Comparing methyl bromide alternatives for soilborne
disease, nematode and weed management in fresh market tomato. Crop
Protection 25: 690-695.

USDA ERS.  2006.  Organic Production.  USDA, Economic Research Service. 
2006.  Available at :    HYPERLINK
"http://www.ers.usda.gov/data/Organic/" 
http://www.ers.usda.gov/data/Organic/ 

USDA NASS.  2002-2006. Crop Production, Summary.  National Agricultural
Statistics Service, U.S. Department of Agriculture, January, at  
HYPERLINK
"http://usda.mannlib.cornell.edu/MannUsda/viewDocumentInfo.do?documentID
=1047" 
http://usda.mannlib.cornell.edu/MannUsda/viewDocumentInfo.do?documentID=
1047 .

USDA NASS.  2005.  Agricultural Chemical Usage, 2004 Field Crops
Summary.  National Agricultural Statistics Service, U.S. Department of
Agriculture, May, at   HYPERLINK
"http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsFC//2000s/2005/Agri
ChemUsFC-05-18-2005.pdf" 
http://usda.mannlib.cornell.edu/usda/nass/AgriChemUsFC//2000s/2005/AgriC
hemUsFC-05-18-2005.pdf .

 PAGE   

Page  PAGE   16