USA CUN13 SOIL Ornamentals Open Field and Protected Environments

NOMINATING PARTY: The United States of America

FILE NAME: USA CUN13 SOIL ORNAMENTALS Open Field and Protected Environments

BRIEF DESCRIPTIVE TITLE OF NOMINATION:

Methyl Bromide Critical Use Nomination for Preplant Soil Use for Ornamentals in Open Fields

and Protection Environments (Submitted in 2011 for 2013 Use Season)

CROP NAME (OPEN FIELD OR PROTECTED): Ornamentals – Open Fields and Protected

QUANTITY OF METHYL BROMIDE NOMINATED:

TABLE 1: QUANTITY OF METHYL BROMIDE NOMINATED

Year NOMINATION AMOUNT

2013 48,164 kg

NOMINATING PARTY CONTACT DETAILS:

Contact Person: John Thompson

Title: Division Director

Address: Office of Environmental Policy

U.S. Department of State

2201 C Street, N.W. Room 2658

Washington, D.C. 20520

U.S.A.

Telephone: (202) 647-9799

Fax: (202) 647-5947

E-mail: thompsonje2@state.gov

Following the requirements of Decision IX/6 paragraph (a)(1) The United States of America has determined that the 

specific use detailed in this Critical Use Nomination is critical because the lack of availability of methyl bromide for 

this use would result in a significant market disruption. ■ Yes  No

Signature Name Date

Title: 

(Details on this page are requested under Decision Ex. I/4(7), for posting on the Ozone Secretariat website under 

Decision Ex. I/4(8).) 

In assessing nominations submitted in this format, TEAP and MBTOC will also refer to the original nomination on 

which the Party’s first-year exemption was approved, as well as any supplementary information provided by the 

Party in relation to that original nomination. As this earlier information is retained by MBTOC, a Party need not 

re-submit that earlier information. 
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

CONTACT OR EXPERT(S) FOR FURTHER TECHNICAL DETAILS:

Contact/Expert Person: Jack Housenger

Title: Director

Address: Biological and Economic Analysis Division

Office of Pesticide Programs

U.S. Environmental Protection Agency

1200 Pennsylvania Avenue, N.W. Mailcode 7503P

Washington, D.C. 20460

U.S.A.

Telephone: (703) 308-8200

Fax: (703) 308-7042

E-mail: Housenger.Jack@epa.gov

LIST OF DOCUMENTS SENT TO THE OZONE SECRETARIAT IN OFFICIAL NOMINATION PACKAGE:

1. PAPER DOCUMENTS: 

Title of paper documents and appendices

No. of pages Date sent to 

Ozone 

Secretariat

2. ELECTRONIC COPIES OF ALL PAPER DOCUMENTS: 

*Title of each electronic file (for naming convention see notes above)

No. of 

kilobytes 

Date sent to 

Ozone 

Secretariat

USA CUN13 SOIL ORNAMENTALS Open Field and Protected Environments

* Identical to paper documents
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

METHYL BROMIDE CRITICAL USE RENOMINATION FOR 

PREPLANT SOIL USE (OPEN FIELD OR PROTECTED ENVIRONMENT)

ORNAMENTALS

1. SUMMARY OF THE NEED FOR METHYL BROMIDE AS A CRITICAL USE:

This re-nomination is for methyl bromide for the production of ornamentals. The ornamental 

sector consists of cut flowers, cut greens, and bulbs in California and floriculture in Florida. All 

data comes from the applicants’ requests unless otherwise cited.

California

Ornamental growers in California have a demonstrated critical need for methyl bromide in 2013. 

Alternatives are not available due to regulatory constraints. Iodomethane (methyl iodide) was 

registered in December of 2010 in California, but its future registration status is uncertain

because of lawsuit that was filed to stop its registration. Many alternative fumigants contain 1,3-

dichloropropene and/or chloropicrin; these active ingredients are severely restricted by California 

state and local laws which effectively prevent their use as methyl bromide alternatives for 

ornamental cultivation. Restrictions on chloropicrin also means the lowest formulation of 

methyl bromide used in California is 67:33 (methyl bromide: chloropicrin), as rates of 

chloropicrin higher than 225 kg/ha are prevented by law and lower rates are ineffective for pest 

control. A single grower may grow dozens of types of species and cultivars, each of which may

experience different pest pressures and may result in varying cultivar and species reactions to 

pest control measures, impacting an alternative’s ability to control the entire pest spectrum.

Florida

Iodomethane has been a registered pesticide in Florida since early 2009. Thus far, research 

results indicate that it is as efficacious as methyl bromide, facilitating a transition away from 

methyl bromide. However, few long-term trials have been conducted and concerns have been 

raised about application techniques and species-specific interactions. For instance, there have 

been no iodomethane trials to treat permanent post-rows using the “hot gas” method, which is a 

common management practice for Florida ornamental growers. Until more studies have been 

done to address these concerns and growers have more time to adapt their production practices, 

there is a critical need for methyl bromide in 2013 as part of a multi-year transition to 

alternatives. Some alternatives that appear effective in research trials are not currently registered, 

including acrolein and dimethyl disulfide (DMDS). 
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

2. REASONS WHY ALTERNATIVES TO METHYL BROMIDE ARE NOT FEASIBLE

The adoption of alternatives to methyl bromide by the ornamentals sector is constrained by 

regulatory prohibitions, yield losses, and higher costs which vary greatly by state. Additionally, 

some constraints apply to the entire ornamentals industry. A single grower may grow dozens of 

types of species and cultivars, each of which may experience different pest pressures. For 

example, a 2008 study in Florida found a significant difference between the pests of two 

cultivars of Delphinium and their pest loads (Rosskopf et al 2008). These differences may result 

in varying cultivar and species reactions to pest control measures, impacting an alternative’s 

ability to control the entire pest spectrum. Methyl bromide is requested for ornamentals to allow 

time to test the alternatives for all the different crops and growing conditions. 

California

In addition to federal regulations, the California Department of Pesticide Regulation (DPR) has 

implemented severe restrictions for soil fumigants, including larger buffer zone requirements and 

township caps, which limit the amount of each fumigant can be applied within a 36-mile area

(Segawa et al 2005). If these restrictions were not in place, the best methyl bromide alternative 

for ornamental growers in California would be 1,3-D plus chloropicrin followed by metam 

sodium (James Gerik, personal communication). A recent study found that this fumigant 

combination was at least as efficacious as methyl bromide (Klose et al 2008). The state buffer 

and township cap regulations currently prevent the use of this alternative. Moreover, another 

recent study found that the most effective alternative treatments contain chloropicrin (Gerik et al 

2002). However, any pesticide combinations including either 1,3-D or chloropicrin are subject to 

prohibitory regulations and can only be considered as alternatives in areas where regulatory

constraints do not restrict their use. Iodomethane received a registration in California in 

December of 2010. The rates registered in California are lower than those registered in the rest 

of the U.S. and the buffer distances to habited structures are up to 10X larger than in the rest of 

the U.S. Research will need to be conducted on the efficacy of these lower use rates.

Some alternatives that appear effective in research trials are not currently registered, including 

acrolein, and DMDS. The future registration status of these products and other alternatives is 

unknown.

Florida

Iodomethane is now fully registered in Florida and recent research results showed it is at least as 

effective as methyl bromide for pest control in Florida ornamentals (Rosskopf et al 2006, 

Rosskopf et al 2007a, Rosskopf et al 2007b, Kokalis-Burelle et al 2006). However, no studies 

have been conducted on the same fields for more than two years, so long-term efficacy and 

application issues have yet to be fully identified and understood. Moreover, efficacy has varied 

between the species and cultivars tested in research trials; it is impossible to predict how each of 

the many species and cultivars of ornamentals would respond to iodomethane. Additionally, 

research is needed on the compatibility of iodomethane with ‘hot gas’ fumigant application 

currently used for methyl bromide; it is a common management method for ornamental growers. 
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

More studies are needed in order to understand the climate-specific constraints faced by Florida 

ornamental growers. The applicants continue to apply for grants and conduct research to this end 

in collaboration with California ornamental growers. DMDS was registered in 2010 for 

ornamentals but not in Florida (registered states currently include: Georgia, Ohio, North and 

South Carolina, Michigan, New Mexico, Tennessee, Texas, and Virginia). If DMDS is 

registered in Florida additional time will be needed because there are very few long term DMDS 

efficacy studies on ornamentals. 

3. IS THE USE COVERED BY A CERTIFICATION STANDARD?

Methyl bromide is not used to meet a certification standard for ornamental production.

4. IF PART OF THE CROP AREA IS TREATED WITH METHYL BROMIDE, 

INDICATE THE REASON WHY METHYL BROMIDE IS NOT USED IN THE OTHER 

AREA, AND IDENTIFY WHAT ALTERNATIVE STRATEGIES ARE USED TO 

CONTROL THE TARGET PATHOGENS AND WEEDS WITHOUT METHYL 

BROMIDE THERE.

Methyl bromide is only being requested for ornamental crop acreage with demonstrated critical 

need and is not being requested for acreage that has had success with alternatives, such as 

caladiums in Florida.

Enclosures

Some ornamental growers using greenhouses have had success controlling pests with substrates. 

Crops successfully grown in soilless media include roses, gerbera, lilies, and tulips. However, 

even substrates are fumigated after multiple cropping seasons to control diseases such as 

Pythium and continue using the substrate, which must be reused in order for the cropping system 

to be cost effective. Certain crops actually experience yield or quality gains when grown in 

substrates, such as roses; however, for most crops there is not such a gain to offset the increased 

costs associated with substrate production. Soilless media systems also require altered watering 

and fertilization management practices, which may incur additional costs. Ultimately, the use of 

substrates requires greenhouses with benches, as opposed to growing crops in enclosures with 

open bottoms to the soil. 

Steam sterilization has been adopted by some shade house and greenhouse growers to produce 

lilies. While steam is considered effective in controlling pests, there are many costs required to 

set up a steaming system within an existing enclosure structure. The cost of fuel required to heat 

soil beds uniformly also impacts the feasibility of steam sterilization. Some growers who 

attempted transitioning to steam sterilization switched back to fumigation due to application 

issues and additional costs. Researchers in California and Florida have looked a steam 

sterilization for ornamental production systems (Rosskopf 2010, and Hanson 2010). This work 

suggests with some additional testing that field applied steam could become a technically and 

economically feasible alternative. 
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

Open Field

The U.S. does not have information about the proportion of ornamental or floriculture crops 

using alternatives to methyl bromide. It can be presumed that acreage not requesting methyl 

bromide has either transitioned to an alternative pesticide or does not have the same cropping 

practices or pest pressure as the applicants with critical use requests. For example, Easter lily 

growers in California now use 1,3-D and metam sodium applied sequentially instead of methyl 

bromide. However, these crops allow fallow periods between crops of more than 10 years, 

which is not feasible for other specialty growers due to limited land resources. Additionally, 

some growers have reduced their planted acreage due to economic hardship in recent years but 

intend to expand plantings and thereby fumigated acres when the economy improves.

5. WOULD IT BE FEASIBLE TO EXPAND THE USE OF THESE METHODS TO 

COVER AT LEAST PART OF THE CROP THAT HAS REQUESTED USE OF 

METHYL BROMIDE? WHAT CHANGES WOULD BE NECESSARY TO ENABLE 

THIS?

No, it is not currently feasible to expand the use of alternative pest control measures to address 

the demonstrated critical needs of the ornamentals sector requesting methyl bromide for the 2013

growing season. Regulatory, technical, and economic barriers prevent their adoption and 

generally vary by state. Research to find efficacious, safe, and cost effective alternatives is 

ongoing, and applicants have a long history of successfully applying for grants and carrying out 

research on alternatives.

California

State and local regulations would have to change in order for fumigants such as 1,3-D and 

chloropicrin to be adopted as methyl bromide alternatives. Other fumigants currently being 

tested may prove effective in research trials but lack registration in the state of California, such 

as DMDS ). Furthermore, some fumigants considered effective in research trials for use in 

California lack both federal and state registration, including dimethyl disulfide and acrolein

(Gerik and Wong 2008). 

Florida

Research is needed in order to determine the long-term efficacy and cost issues associated with 

iodomethane adoption as a methyl bromide alternative. More research is also needed on 

nonfumigant alternatives such as steam. Critical use of methyl bromide could be further reduced 

by changing the label to allow concentrations lower than 98:2 (methyl bromide: chloropicrin) to 

be applied using the ‘hot gas’ method, which is a common management practice. Concentrations 

as low as 50:50 (methyl bromide: chloropicrin) have been found to achieved comparable control 

of nematodes and nutsedge as with the 98:2 formula (Noling et al 2001).

6. SUMMARY OF RECENT RESEARCH

CALIFORNIA
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

Hanson, B. 2010. Steam Disinfestation as a Methyl Bromide Alternative in California Cut Flower 

Nurseries. Proceedings of the Annual International Research Conference on Methyl Bromide 

Alternatives and Emissions Reductions. 

http://mbao.org/2010/085HansonBSteamflowernursery.pdf

Steam treatments were compared to methyl bromide for the production of snapdragon, and 

Asiatic lily in California. There were no difference between MeBr and steam for weed or 

Fusarium control at the snapdragon site. At the Asiatic lily site there were no difference in 

Fusarium or Pythium control, weed control or lily plant emergence. 

FLORIDA

Rosskopf, E.N., N. Kokalis-Burelle, E. Nissen, O. Nissen, R. Hartman, R. McSorley, E. Skvarch, 

T.J. Swaford, C. Owens, S. Brooks, and K. Register. 2010. Evaluation of currently available 

alternatives to methyl bromide for ornamental crop production in Florida. Proceedings of 

the Annual International Research Conference on Methyl Bromide Alternatives and 

Emissions Reductions. http://mbao.org/2010/082RosskopfAreawideOrnamental..pdf

The 2010 results were different than the 2008 results above. No significant difference between 

methyl bromide, DMDS, or iodomethane in terms of soil borne fungi., However, none of the 

alternatives were as consistent as methyl bromide for weed control and there was a fungal plant 

pathogen with nematode interaction for the different fumigants that will need to be resolved.. 

Rosskopf, E.N., N. Kokalis-Burelle, D.M. Butler, J. Holzinger, S. Fennimore. 2010. Evalution 

of steam for nematode and weed control in cut flower production inFlorida. Proceedings of 

the Annual International Research Conference on Methyl Bromide Alternatives and 

Emissions Reductions. http://mbao.org/2010/083RosskopfSteam.pdf

The results of the 2010 study suggests that steam sterilization can control weeds, reduce root gall 

ratings compared to MeBr on snapdragon, larkspur, and delphinium. The production of 

snapdragon, larkspur, and delphinium appeared similar between MeBr and steam treatments. 

7. ECONOMIC FEASIBILITY OF ALTERNATIVES 

Please note that in this study net revenue is calculated as gross revenue minus operating costs. 

This is a good measure as to the direct losses of income that may be suffered by the users. It 

should be noted that net revenue does not represent net income to the users. Net income, which 

indicates profitability of an operation for an enterprise, is gross revenue minus the sum of 

operating and fixed costs. Net income is smaller than the net revenue measured in this study, 

often substantially so. We did not include fixed costs because they are difficult to measure and 

verify.
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

TABLE 2: CALIFORNIA CUT FLOWERS - CALLA LILY & RANUNCULUS - ECONOMIC IMPACTS OF 

METHYL BROMIDE ALTERNATIVES

California Cut Flowers – Calla Lily & Bulbs METHYL 

BROMIDE

1,3-D + Pic Dazomet Metam

Sodium

YIELD LOSS (%) 0 25 25 20

 YIELD PER HECTARE 55,937 41,952 41,952 44,749

* PRICE PER UNIT (U.S.$) 2.59 2.59 2.59 2.59

= GROSS REVENUE PER HECTARE (U.S.$) 145,107 108,830 108,830 116,086

- OPERATING COSTS PER HECTARE (U.S.$) 160,030 160,030 160,030 160,030

= NET OPERATING REVENUE PER HECTARE (U.S.$) -14,923 -51,200 -51,200 -43,945

1. LOSS PER HECTARE (U.S.$) 0 36,277 36,277 29,021

2. LOSS PER KILOGRAM OF METHYL BROMIDE 

(U.S.$) 0 137 137 110

3. LOSS AS A PERCENTAGE OF GROSS REVENUE (%) 0 25 25 20

4. LOSS AS A PERCENTAGE OF NET OPERATING 

REVENUE (%) 0 -243 -243 -194

TABLE 3: FLORIDA CUT FLOWERS - LILIES - ECONOMIC IMPACTS OF METHYL BROMIDE 

ALTERNATIVES

Florida Cut Flowers – Lilies METHYL BROMIDE

IODOMETHANE +

PIC (98:2)

YIELD LOSS (%) 0 0 

 YIELD PER HECTARE 31,135 31,135

* PRICE PER UNIT (U.S.$) 10 10

= GROSS REVENUE PER HECTARE (U.S.$) 311,353 311,353

- OPERATING COSTS PER HECTARE (U.S.$) 262,715 262,715

= NET OPERATING REVENUE PER HECTARE (U.S.$) 48,638 46,908

1. LOSS PER HECTARE (U.S.$) 0 1,730

2. LOSS PER KILOGRAM OF METHYL BROMIDE (U.S.$) 0 4

3. LOSS AS A PERCENTAGE OF GROSS REVENUE (%) 0 1

4. LOSS AS A PERCENTAGE OF NET OPERATING REVENUE (%) 0 4

Summary of Economic Feasibility

The economic analysis evaluated methyl bromide alternative control scenarios for cut flower 

production for California and Florida by comparing the economic outcomes of methyl bromide 

oriented production systems to those using alternatives. However, due to the fact that there are 

over 100 species of ornamentals grown in all regions of the country, the data from these 

examples are used to derive a proxy estimate for the entire industry. A major factor that affected 

this economic analysis as compared to the past economic analyses was the availability of 

iodomethane (registered in 2008) in Florida, but not in California for use in ornamentals. 

The economic factors that most influence the feasibility of methyl bromide alternatives for fresh 

cut flower production are: (1) yield losses, referring to reductions in the quantity and quality 

produced, (2) increased production costs, which may be due to the higher-cost of using an 

alternative, additional pest control requirements, and/or resulting shifts in other production or 

harvesting practices, and (3) missed market windows due to plant back time restrictions, which 

also affect the quantity and price received for the goods.
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

The economic reviewers analyzed crop budgets for pre-plant sectors to determine the likely

economic impact if methyl bromide were unavailable. Various measures were used to quantify

the impacts, including the following: 

(1) Loss per Hectare. For crops, this measure is closely tied to income. It is relatively easy to 

measure, but may be difficult to interpret in isolation.

(2) Loss per Kilogram of Methyl Bromide. This measure indicates the nominal marginal value 

of methyl bromide to crop production.

(3) Loss as a Percentage of Gross Revenue. This measure has the advantage that gross revenues 

are usually easy to measure, at least over some unit, e.g., a hectare of land or a storage operation. 

However, high value commodities or crops may provide high revenues but may also entail high 

costs. Losses of even a small percentage of gross revenues could have important impacts on the 

profitability of the activity.

(4) Loss as a Percentage of Net Operating Revenue. We define net cash revenues as gross 

revenues minus operating costs. This is a very good indicator as to the direct losses of income 

that may be suffered by the owners or operators of an enterprise. However, operating costs can 

often be difficult to measure and verify.

These measures represent different ways to assess the economic feasibility of methyl bromide 

alternatives for methyl bromide users, who are producers in this case. Because producers 

(suppliers) represent an integral part of any definition of a market, we interpret the threshold of 

significant market disruption to be met if there is a significant impact on commodity suppliers 

using methyl bromide. The economic measures provide the basis for making that determination.

Several methodological approaches will help interpret the findings. Economic estimates were 

first calculated in pounds and acres and then converted to kilograms and hectares. Costs for 

alternatives are based on market prices for the control products multiplied by the number of 

pounds of active ingredient that would be applied. Baseline costs were based on the average 

number of annual applications necessary to treat cut flowers with methyl bromide.

Net revenue is calculated as gross revenue minus operating costs. This is a good measure as to 

the direct losses of income that may be suffered by the users. It should be noted that 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 difficult to measure and verify. 

Loss per hectare measures the value of methyl bromide based on changes in operating costs 

and/or changes in yield. Loss expressed as a percentage of the gross revenue is based on the 

ratio of the revenue loss to the gross revenue, likewise for the loss as a percentage of net revenue. 

Yield loss estimates were based on data from the CUE applications and U.S. EPA data, as well 

as expert opinion.
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

Regulatory constraints

California restricts total use of 1,3-D at the local level (township cap). Nematodes and weeds 

and pathogens are key pests in Florida and California bulb grower and are controlled with methyl 

bromide. Chloropicrin is not as effective in controlling weeds as methyl bromide. Using 

chloropicrin adds to production costs through increased chemical, weeding and labor costs.

Tables 2 though 4 provide a summary of the estimated economic losses. A measure of net 

revenue loss may not be completely accurate partly because some nurseries are publicly owned 

and seedling prices or production costs are subsidized. Indirect losses arising from shifts in the 

production cycle were not quantified. Changes in production costs arise due to differences 

between the costs of methyl bromide and the alternatives, shifts in the production cycle 

(increasing the frequency of fumigation or lengthening the fallow period) and additional 

expenses such as supplementary irrigation. These costs vary across regions. 

As shown in Table 2, the alternatives to methyl bromide for California cut flower production 

impose significant economic impacts on the growers. However, in Florida where iodomethane is 

available for use in ornamentals, economic impacts of using iodomethane as an alternative to 

methyl bromide are small. 

8. RESULTANT CHANGES TO REQUESTED EXEMPTION QUANTITIES

Table 4. Nomination Amount.

 California Cut

Flower

Commission 

 Florida Cut

Flowers 

 Sector Total / 

Average

Quantity Requested for 2012: Amount (kgs) 46,950 1,214 48,164

Quantity Recommended by 

MBTOC/TEAP for 2012 :

Amount (kgs) 46,950 1,214 48,164

Amount (kgs) 46,950 1,214 48,164

Area (ha) 261 61 322

Rate 180 20 150

Transition from 2012 Baseline 

Adjusted Value

Percentage 

(%)

0% 0% 0%

Amount (kgs)

 46,950 1,214 48,164

Area (ha) 235 6 241

Rate 200 200 200

Quantity Approved by Parties 

for 2012:

Quantity Required for 

2013 Nomination:

ORNAMENTALS

SECTOR
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

CITATIONS

Rosskopf, E.N., N. Kokalis-Burelle, E. Nissen, O. Nissen, R. Hartman, R. McSorley, E. Skvarch, 

T.J. Swaford, C. Owens, S. Brooks, and K. Register. 2010. Evaluation of currently available 

alternatives to methyl bromide for ornamental crop production in Florida. Proceedings of 

the Annual International Research Conference on Methyl Bromide Alternatives and 

Emissions Reductions. http://mbao.org/2010/082RosskopfAreawideOrnamenta.pdf

Rosskopf, E.N., N. Kokalis-Burelle, D.M. Butler, J. Holzinger, S. Fennimore. 2010. Evalution 

of steam for nematode and weed control in cut flower production inFlorida. Proceedings of 

the Annual International Research Conference on Methyl Bromide Alternatives and 

Emissions Reductions. http://mbao.org/2010/083RosskopfSteam.pdf

Gerik, JS; CL Elmore, ID Greene. 2002. Alternative soil treatments for field grown ornamentals. 

Proceedings of the Annual International Research Conference on Methyl Bromide 

Alternatives and Emissions Reductions. 

http://mbao.org/2002proc/093gerikj%20mbao_2002.pdf

Gerik, James and Dong Wang. 2008. Control of Agrobacterium tumafaciens with soil fumigants. 

Proceedings of the Annual International Research Conference on Methyl Bromide 

Alternatives and Emissions Reductions. http://mbao.org/2008/110Gerik.pdf

Gerik, James. Personal communication via telephone. October 28, 2008.

Hanson, B. 2010. Steam Disinfestation as a Methyl Bromide Alternative in California Cut Flower 

Nurseries. Proceedings of the Annual International Research Conference on Methyl Bromide 

Alternatives and Emissions Reductions. 

http://mbao.org/2010/085HansonBSteamflowernursery.pdf

Klose, Susanne; Jim Gerik, Hussein Ajwa, Cheryl Wilen, Mike Mellano. 2008. Proceedings of 

the Annual International Research Conference on Methyl Bromide Alternatives and 

Emissions Reductions. http://mbao.org/2008/029Klose.pdf

Kokalis-Burelle, Nancy; Erin Rosskopf, Randy Driggers. 2006. Efficacy of Midas for control of 

Meloidognye incognita on Celosia in Florida. Proceedings of the Annual International 

Research Conference on Methyl Bromide Alternatives and Emissions Reductions. 

http://mbao.org/2006/06Proceedings/112BurelleNMBAOAbstractBurelleetal2006.pdf

McSorley, R., Wang, K.H., Church, G. 2004. Fumigant alternatives to methyl bromide for 

managing nematodes and weeds in snapdragon. Proceedings of Florida State Horticulture 

Society. 117:334-337.

National Agricultural Statistics Service (NASS). 2008. Floriculture Crops 2007 Summary. 

USDA Sp Cr 6-1 (08)

http://usda.mannlib.cornell.edu/usda/current/FlorCrop/FlorCrop-04-24-2008.pdf
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

Noling, J.W; J.P. Gilreath, E.R. Rosskopf. 2001. Alternatives to methyl bromide field research 

efforts for nematode control in Florida. Proceedings of the Annual International Research 

Conference on Methyl Bromide Alternatives and Emissions Reductions. 

http://mbao.org/2001proc/014%20Noling%20JW%20MBAO2-2001.pdf

Rosskopf, Erin; D.O. Chellemi, N. Kokalis-Burelle, G.T. Church. 2005. Alternatives to methyl 

bromide: a Florida perspective. APSnet Feature June 2005: 

http://www.apsnet.org/online/feature/methylbromide/

Rosskopf, Erin; Nancy Kokalis-Burelle, Randy Driggers. 2006. Evaluation of Midas for 

production of ornamental cockscomb in Florida. Proceedings of the Annual International 

Research Conference on Methyl Bromide Alternatives and Emissions Reductions. 

http://mbao.org/2006/06Proceedings/037Rosskopfetalcelosia2006.pdf

Rosskopf, Erin; Nancy Kokalis-Burelle, and Randy Driggers. 2007a. Reduced rates and 

alternatives to methyl bromide for snapdragon production in Florida. Proceedings of the 

Annual International Research Conference on Methyl Bromide Alternatives and Emissions 

Reductions. http://mbao.org/2007/Proceedings/106RosskopfEMBAOsnapdragon2007.pdf

Rosskopf, EN; JS Gerik, NK Burelle, G Church, R McSorley. 2007b. Status of methyl bromide 

alternatives for ornamental crop production in Florida and California. American 

Phytopathological Society Annual Meeting.

Rosskopf, Erin and Nancy Kokalis-Burelle. 2008. Area-wide demonstration of chemical 

alternatives to methyl bromide for Florida ornamentals. Proceedings of the Annual 

International Research Conference on Methyl Bromide Alternatives and Emissions 

Reductions. http://mbao.org/2008/028Rosskopf.pdf

Segawa, Randy. 2005. Methods for developing fumigant regulatory requirements in California. 

Proceedings of the Annual International Research Conference on Methyl Bromide 

Alternatives and Emissions Reductions. 

http://mbao.org/2005/05Proceedings/001%20SegawaR%20mbao_2005_conf_segawa_sum

mary.pdf

Zinati, Gladis; Herbert Bryan and Merlyn Codallo. 2002. Solarization as a potential approach for 

recycling wastes for potting media and as an alternative to methyl bromide for field-grown 

bedding plants. Proceedings of Florida State Horticulture Society. 115: 123 – 127.
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

APPENDIX A: ORNAMENTAL SPECIES GROWN 

The very large and constantly changing number of species and cultivars grown in the 

ornamentals sector means that compiling a complete list of species and acreage grown is not 

possible. There are hundreds of types of cut flower, foliage, and bulb crops grown each year and 

often several species are grown in the same field simultaneously. However, the U.S. has tried to 

describe the major crops below. Additional information is not available from public or private 

sources.

California

APPENDIX B -TABLE 1: CALIFORNIA ORNAMENTALS - PRODUCTION OF MAJOR SPECIES

SPECIES # FLOWER BUNCHES IN 2003

Alstroemeria 892,789

Carnations 1,694,870

Delphinium 3,617,186

Gladiolus Data not released

Gerbera 62,638,650

Iris 5,823,242

Lilium 6,247,027

Chrysanthemums 1,273,742

Pompons 6,350,127

Roses 7,360,729

Snapdragons 2,976,219

APPENDIX B - TABLE 2: CALIFORNIA ORNAMENTALS - PARTIAL LISTING AND ESTIMATE OF CUT FLOWER AND 

FOLIAGE AREA PRODUCED IN CALIFORNIA IN 2002

CROP AREA (USUALLY FIELD) - HA AREA (USUALLY GREENHOUSE) - HA

Alstroemeria 8 5

Antirrhinum (snapdragon) 126 17

Aster 6

Calla lily 16

Carnation 30 2

Chrysanthemum 88 28

Delphinium 22

Eucalyptus 54

Gerbera 21

Gypsophila 55

Iris (Dutch) 18

Larkspur 6

Lilium 32 21

Limonium spp. 13

Lisianthus 13

Protea 190

Rose 41 12

Stock (Matthiola) 26

Wax flower 317

Other 791 6

Greenhouse misc. 70 28

Field misc. 303

Cut greens misc. 389

Total 2609 145 ha

1

 Total does not add due to rounding. 
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

Florida 

The only three cut flower species identified by the Florida Agricultural Statistics Service are 

gladioli, lilies and snapdragon. These are assumed to have the highest acreage and they have 

been identified by the applicant as using methyl bromide. 

APPENDIX B TABLE 3. FLORIDA ORNAMENTALS - CROP PRODUCTION FOR CERTAIN CUT FLOWER SPECIES2

2001 2002 2003

CROP

# OF 

PRODUCERS

QUANTITY 

SOLD (1000

SPIKES)

1

# OF 

PRODUCERS

QUANTITY 

SOLD (1000

SPIKES)

1

# OF 

PRODUCERS

QUANTITY 

SOLD (1000

SPIKES)

Gladioli 4 40,331 4 49,581 4 39,444

Snapdragons 5 6,806 4 4,415 4 4,757

Lilies 4 3,031 3 2,257 - -

1 Quantity of lilies sold 1000 stems.

2 This table only includes data for growers with sales over $100,000.
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

APPENDIX B: KEY TARGET PESTS

The ornamentals industry is complex; therefore, the following list is not comprehensive but is 

intended to demonstrate the large number of pests affecting ornamental production and creating a 

critical need for methyl bromide in the U.S. for the 2013 growing season.

TABLE C 1. KEY PESTS

Region where 

methyl 

bromide use 

is requested

Key disease(s) and weed(s) to 

species and, if known, to level of 

race

Specific reasons why methyl bromide needed (e.g. 

Effective herbicide available, but not registered for this 

crop; mandatory requirement to meet certification for 

disease tolerance; no host resistance for a specific race)

A: California 

Cut Flowers, 

Cut Greens 

and 

Perennials

Verticillium spp., Fusarium spp., 

Pythium spp., Meloidogyne spp., 

Nutsedge (Cyperus spp.), Malva spp., 

Poa spp., and previous crop

propagules. Specific pest problems 

vary by individual crop and variety. 

The diversity and complexity of the industry, makes it

difficult to control all root pathogens and weeds with 

currently available pest control methods. Some methyl 

bromide alternatives used for other sectors are not

feasible for floriculture due to high costs, difficulty 

timing applications to allow intercropping, and regulatory 

restrictions including township caps and buffer zone 

requirements.

B: Florida 

Floriculture

Soilborne diseases, weeds, and 

nematodes including Fusarium spp., 

Rhizoctonia spp., Phytoplithora, 

Stromatinia, Pythium spp., Erwinia, 

and most soil nematodes e.g. 

Meliodogyne spp., and previous crop 

propagules. Specific pest problems 

vary by individual crop and variety. 

These diseases are common, abundant, and spread via

water, exacerbated by Florida’s regions of tropical and 

sub-tropical climates. Due to the complexity of the 

ornamentals sector, alternative pest control measures

have not been found for all species but research efforts 

are ongoing. Iodomethane is now registered; however, 

other methyl bromide alternatives preliminarily 

considered effective, such as dimethyl disulfide, are not 

currently registered for use. 
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

APPENDIX C: STATUS OF METHYL BROMIDE ALTERNATIVES

TABLE C 1. REASON FOR ALTERNATIVES N OT BEING FEASIBLE

NAME OF 

ALTERNATIVE

TECHNICAL AND REGULATORY* REASONS FOR THE ALTERNATIVE NOT BEING FEASIBLE OR 

AVAILABLE

1,3-

Dichloropropene 

(1,3-D) 

Technical

Controls nematodes but will not provide adequate control of diseases and weeds at label rates. 

Regulatory

Buffer zones limit its use and township caps in Florida and California further restrict its use in 

those states. Mandated plant-back times can be 1 to 2 weeks longer with 1,3-D than with other 

fumigants. 1,3-D is not registered for use in greenhouses.

Chloropicrin

Technical 

Weed control is poorer than with methyl bromide Control of the entire pest spectrum cannot be 

achieved with lower use rates, but there are concerns about phytotoxicity to nearby plantings if 

greater than 2% chloropicrin is used in a fumigant combination 

Regulatory 

There is concern over the real or perceived public exposure to higher rates of chloropicrin, 

especially in highly populated urban areas, due to increased worker exposure, offsite 

movement, and smells.

Metam sodium

Technical

Efficacy data is inconsistent, depending on soil type, moisture content, and temperature.

Regulatory

Metam sodium is not registered for use in greenhouses.

Iodomethane

Technical

More research needs to be done to understand application and long-term efficacy issues.

Regulatory

Iodomethane is not registered for use in California. Large buffer zones and lower use rates may 

also prevent widespread adoption.

1,3-D + 

chloropicrin

Technical 

This alternative does not control the entire pest spectrum.

Regulatory

In California, 1,3-D + chloropicrin is considered one of tthe best currently available 

alternatives, if label application rates were increased Township caps and buffer zones that exist 

for the individual chemicals also apply for the combination. 

Metam sodium + 

chloropicrin

Technical

This combination does not adequately control nematodes and weeds, and performance is 

inconsistent. 

Regulatory

Restrictions and concerns existing for the individual chemicals also apply for the combination.

1,3-D + metam 

sodium

Technical

Efficacy data is inconsistent. 

Regulatory

Restrictions for the individual chemicals also apply for the combinations.
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

NAME OF 

ALTERNATIVE

TECHNICAL AND REGULATORY* REASONS FOR THE ALTERNATIVE NOT BEING FEASIBLE OR 

AVAILABLE

1,3-D + 

chloropicrin + 

metam sodium

Technical

Weed control is incomplete.

Regulatory

In California, 1,3-D + chloropicrin is considered the best currently available alternative, if use 

restrictions, such as township caps, were removed. Restrictions existing for the individual 

chemicals also apply for the combinations.

1,3-D + 

chloropicrin + 

herbicides

Technical

None.

Regulatory

Restrictions existing for the individual chemicals also apply for combinations.

Dazomet

Technical:

Dazomet does not control the entire pest spectrum unless in combination with 1,3-D, 

chloropicrin, and/or herbicides.

Regulatory:

Restrictions on 1,3-D and chloropicrin prevent the use of Dazomet as a methyl bromide 

alternative.

Metam sodium + 

crop rotation

Technical

Treatment does not control the entire pest spectrum.

Regulatory 

Restrictions existing for metam sodium also apply to its use in combination with other pest 

control measures. 

Steam

Technical

Steam sterilization is not feasible in open field production due to the need to remove the steam 

piping after application in order to accommodate cultural management practices. In 

greenhouses, steam has been successfully used in previous decades as a pest control method.

Regulatory

None. 

Biological control 

agents

Technical

No biological controls have been developed to cover all of the pests. 

Regulatory

None.

Crop rotation

Technical:

Previous crops’ bulbs and corms often contaminate the following crop as volunteer weeds or 

reservoirs for pathogens. 

Regulatory

None.

Herbicides

Technical:

Crop damage may occur from contact with certain herbicides or in the following crop if soil 

residues remain. 

Regulatory

Restrictions for registered pesticides vary depending on the active ingredient(s) and individual 

product labels.
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

NAME OF 

ALTERNATIVE

TECHNICAL AND REGULATORY* REASONS FOR THE ALTERNATIVE NOT BEING FEASIBLE OR 

AVAILABLE

Biofumigation

Technica:l

Biofumigation is still largely in the experimental stages. Specific brassicas as well as specific 

years yield variable amounts of activity. While this alternative may provide some control, the 

control of all target pests is not sufficient. 

Regulatory:

None. 

Substrates

Technical:

The use of substrates is only technically feasible in greenhouses using benches,

Regulatory

None. 

Dimethyl 

disulfide 

(DMDS)

Technical:

Studies are currently being conducted to test the efficacy of DMDS in ornamentals under an 

Experimental Use Permit.

Regulatory:

DMDS is not currently registered in Florida or California, and its future registration status is 

not known.

Acrolein

Technical:

Studies are currently being conducted to determine the efficacy of acrolein for ornamentals.

Regulatory:

Acrolein is currently only registered as an aquatic herbicide and cannot be used on soil for this 

use. Its future registration status is unknown.

Propargyl 

bromide

Technical:

More research is needed to understand its efficacy as a methyl bromide alternative.

Regulatory:

This alternative is not currently registered and its future regulatory status is unknown. 

Sodium azide

Technical:

More research is needed to understand its efficacy.

Regulatory:

This alternative is not currently registered and its future regulatory status is unknown.

Muscador albus 

Strain QST 

20779

Technical:

No commercially available formulation.

Regulatory:

None.

Ethane dinitrile 

(Cyanogen)

Technical:

Considered a viable alternative in Australia, no studies have been conducted in the U.S.

comparing efficacy with methyl bromide and other alternatives.

Regulatory:

This product is not currently registered in the U.S. and its future registration status is unknown.

Acidic 

electrolyzed 

oxidizing (EO) 

water

Technical:

EO water only controls foliar fungal diseases in greenhouse ornamentals. No research has been 

conducted on this product as a pre-plant pesticide in at least 6 years.

Regulatory:

There is no commercial development or planned registration of this product currently.
USA CUN13 SOIL Ornamentals Open Field and Protected Environments

NAME OF 

ALTERNATIVE

TECHNICAL AND REGULATORY* REASONS FOR THE ALTERNATIVE NOT BEING FEASIBLE OR 

AVAILABLE

Solarization

Technical:

Efficacy data is inconsistent between research trials. Regional subclimates with significant 

cloud cover or cooler annual temperatures will not receive enough degrees for solarization to be 

a feasible pest control option. 

Regulatory:

None.

Furfural

Technical:

It does not control the entire pest spectrum.

Regulatory:

Furfural has a federal registration for ornamentals and non-food commodities for greenhouse

soil use only. However, it does not have state registrations currently, and its future registration 

status is unknown..

Regulatory reasons include local restrictions (e.g. occupational health and safety, local environmental regulations) 

and lack of registration.