EMERGENCY EXEMPTION REQUEST 

(Specific Exemption} 

FOR THE USE OF 

FireWall SOWP Fungicide/Bactericide (streptomycin sulfate} 

TO MANAGE 

Citrus Canker (Xanthomonas axonopodis pv. citn) 

ON 

Grapefruit 

IN FLORIDA 

December 18, 2014 

1 
TABLE OF CONTENTS 

CONTACT PERSONCS) AND QUALIFIED EXPERTS (166.20(al<1ll .................... 3 

DESCRIPTION OF PESTICIDE REQUESTED (166.20(a)(2)) ........................ ...... 3 

DESCRIPTION OF PROPOSED USE (166.20(a)(3ll ........................................... 4 

ALTERNATIVE METHODS OF CONTROL (166.20(alC4)) .................................... 6 

EFFICACY OF USE PROPOSED UNDER SECTION 18 (166.20Cal<5)) ................. 9 

DISCUSSION OF RESIDUES IN FOOD (166.20(a)(6)) .................................... 10 

DISCUSSION OF RISK INFORMATION (166.20(a)(7)) ................................... 10 

FQPA INFORMATION (OCTOBER 24, 1996 EPA LETTER) ................................. 11 

COORDINATION WITH OTHER AFFECTED FEDERAL, STATE, AND LOCAL 

AGENCIES (166.20Ca)(8) ................................................................................. 12 

NOTIFICATION OF REGISTRANT {166.20(a)(9)) ............................................ 12 

DESCRIPTION OF ENFORCEMENT PROGRAM (166.20(a)(10l) ...................... 12 

REPEAT USES C166.20(al(11)) ........................................................................ 12 

PROGRESS TOWARD REGISTRATION (166.20(b)l2)(iil) ............................... 12 

NAME OF PEST (166.20(b)(1)) ........................................................................ 13 

DISSUCION OF ECONOMIC LOSS (166.20{b)(4)) ........................................... 16 

ESTIMATED REVENUES FOR THE SITE TO BE TREATED 

(166.20(8)(4) ii 8t iii) ····················································································-··· 23 

2 
CONTACT PERSONCSl AND QUALIFIED EXPERTS(Sl C166.20(al(l)) 

(i) The Contact Person for matters relating to the administration of this 

exemption: 

Michael J. Aerts 

Florida Fruit & Vegetable Association 

800 Trafalgar Ct.; Suite 200 

Post Office Box 948153 

Maitland, FL 32794-8153 

Phone: (321) 214-5200 

Fax: (321) 214-0210 

mike.aerts@ffva.com 

Charlie Clark, Environmental Admin. 

FL Dept. of Ag and Consumer Services 

Pesticide Registration Section 

3125 Conner Blvd. (Bldg. 6) 

Tallahassee, FL 32399-1650 

Phone: (850) 617-7940 

Fax: (850) 617-7949 

charlie.clark@freshfromflorida.com 

(ii) The contact people for matters relating to the technical aspects of this 

exemption: 

For Florida, it has been agreed that questions relating to technical aspects in the 

field for this emergency exemption petition will work through the Florida 

Department of Agriculture and Consumer Services and the Emergency Response 

Team within EPA's OPP. 

DESCRIPTION OF PESTICIDE REQUESTED (166.20(al(2)) 

a. Common Chemical Name (Active Ingredient): 

Streptomycin Sulfate 

Trade Name and EPA Registration Number: 

FireWaiiSOWP Fungicide/Bactericide 

EPA Registration Number: 80990-4 

Formulation: 

Wettable Powder 

Percent Active Ingredient: 

65.8°/o (equivalent to 50% streptomycin) 

Manufacturer: 

AgroSource, Inc. 

3 
b. Additional labeling: see Appendix A for a proposed Section 18 label. 

DESCRIPTION OF PROPOSED USE C166.20(a)(3)) 

(i) Sites to be Treated: 

Grapefruit (statewide). According to the latest figures available from the 

USDA National Agricultural Statistics Service, for the 2012-13 season there 

were a total of approximately 47,656 acres of grapefruit growing in Florida 

(44,900 bearing acres and 2,756 non-bearing acres). Putting this figure 

into perspective, prior to the discovery of citrus canker in Florida and the 

subsequent eradication program that followed, a total of nearly 140,000 

acres of grapefruit were grown in Florida. Grapefruit acreage statewide 

would be eligible for this fungicide/bactericide treatment, although much of 

the usage would occur in the commercial grapefruit producing counties 

such as Polk, Hendry, Highlands, De Soto, Hardee, St. Lucie, Indian River, 

Collier, Manatee and Martin Counties. See Appendix C for Florida counties 

and acreages in grapefruit. 

(ii) Method of APplication: 

Ground application only. 

(iii) Rates of Application (in terms of a.i. and product): 

0.344 pounds of active ingredient per acre per application 

0.6875 pounds of formulated FireWall 50WP Fungicide/Bactericide per acre 

per application 

Maximum Number of Applications: 

A maximum of 2 applications per crop can be made, totaling no more than 

1.375 pounds of formulated product (0.6&f lbs. ~(.) per ~ ..... 

. ·, 

(iv) Total Acreage (or other units) to be Treated: 

During 2012-13, approximately 47,656 acres of grapefruit were grown in 

Florida. 

4 
(v) Total Amount of Pesticide to be Used Cin terms of a.i. and product): 

In an absolute worst-case scenario, 192,764 pounds of FireWall 50WP 

Fungicide/Bactericide, or 43,179 pounds of streptomycin sulfate, would be 

needed. (47,656 acres X 1.375 pounds= 65,527 pounds FireWall 50WP 

Fungicide/Bactericide; 47,656 acres X 0.6875 lbs. a.i. = 32,763 lbs. a.i. 

streptomycin). 

While these amounts of product may be needed under a worst case 

scenario, it is highly probable that considerably less than all of the eligible 

acreage will be treated, and a portion of that acreage will not receive the 

full 1.375 pounds of FireWall per acre per season rate. 

(vi) Use Season (period of time for which use of chemical is 

requested): 

Access would be needed by April 1, 2015 at the very latest. Availability 

subsequent to the date of approval is again requested and crucial over the 

ensuing 12 months, especially when considering the continued grapefruit 

tree losses due to citrus canker and also to citrus greening disease. 

(vii) Additional Restrictions, User Precautions and Requirements, 

Qualifications of Applicators, etc.: 

Products will be applied in accordance with the proposed Section 18 label 

and all applicable provisions of the Section 3 registered label. Examples of 

various restrictions, requirements and qualifications include but are not 

limited to: 

• A total of two (2) applications of FireWall SuWP Fungieid~/Bactericide 

may be made at approximately 21 day interv ~,. . Use will be during the 

summer when the risk of phytoxicity from alternate products is highest 

and/or when· risk of wind-blown rains and associated inoculum 

redistribution is greater. 

• Do not apply within 60 days of harvest. 

• Worker re-entry into treated areas during the restricted entry int~n13! of 

12 hours is not allowed. Personal protective equipment for applh:ntn•s 

and handlers includes: 

• Long-sleeved shirt; 

• Long pants; 

• Chemical-resistant gloves made of any waterproof materia:; 

• Shoes plus socks; and, 

• MSHA/NIOSH approved dust/mist respirator with any R, P 0 r ~E 

filter. 

5 
• Personal Protective Equipment required for early entry to treated areas 

that is permitted under the Worker Protection Standard and that 

involves contact with anything that has been treated, such as plants, 

soil, or water is: 

• Coveralls over long-sleeved shirt and long pants; 

• Chemical-resistant gloves, made of any waterproof material; and, 

• Shoes plus socks. 

• For this proposed Emergency Exemption, applications through any type 

of irrigation system (i.e., chemigation) are prohibited. 

• Do not apply more than 1.375 pounds of formulated FireWall SOWP 

Fungicide/Bactericide (0.6875 lbs. a.i.) per acre per season. 

• Do not apply directly to water, or to areas where surface water is 

present, or to intertidal areas below the mean watermark. 

• Do not contaminate water when disposing of equipment wash water or 

rinsate or disposal of waste. 

• The FireWall label contains a CAUTION statement of hazard and this 

product is considered to be a "General Use" pesticide. As a nonrestricted pesticide, farmers without private applicator certification, 

farmers with private applicator certification, and, licensed commercial 

applicators, are allowed to apply FireWall. 

Other specific use directions to be followed are found on the proposed 

Section 18 label and the Section 3 label found in Appendix A. 

ALTERNATIVE METHODS OF CONTROL C166.20(a){4) ): 

(i) Detailed Explanation of Why Currently Registered Pesticides Are 

Not Available in Adequate Supply and/or Are Not Effective to Control the 

Emergency: 

No EPA-registered bactericides exist for citrus canker management other 

than copper. Multiple disadvantages of season-long, long-term use of 

copper bactericides for citrus canker control have been documented 

including fruit phytotoxicity when applying copper in hot weather, ind•-•ction 

of copper-resistance in Xanthomonas axonopodis pv. citri (Xac) popvlr.ltit •ns, 

and accumulation of copper in citrus soils with potential phytotoxic and 

adverse environmental effects. 

A risk of season-long application of copper fungicides to grapefruit, 

especially during/after hot, dry periods, is phytotoxicity to the fruit rind, 

which is what has now created this non-routine emergency situation. 

Copper phytotoxicity results when a "burn" causes rind tissues to dev~l0r 

corky lesions, resulting in a blemish called "star melanose." On grape~r uit, 

these blemishes make the fruit completely unacceptable for the fresh 

6 
market, which is the market to which Florida grapefruit are initially grown. 

The production strategy for Florida grapefruit follows stringent requirements 

in order to make the crop available for the fresh market. A production 

strategy for a fresh market crop from the beginning of the season through 

to completion is significantly more intense, expensive and time consuming 

than for a crop destined for a processing market. 

In Florida on grapefruit, copper hydroxide and copper sulfate applied at 14-

or 21-day intervals does in fact manage citrus canker on the fruit, but 

simultaneously the copper component causes considerable burning on the 

fruit rind when it's hot. Field studies have shown that alternation of 

streptomycin (FireWall) with a reduced rate of copper sulfate during warm 

periods of the summer provide similar reductions in diseased fruit with 

minimal copper burn compared to that of the full rate of copper alone. 

Burn reduction with a reduced rate of copper was similar to that seen by 

alternating copper with a strobilurin fungicide (Headline/pyraclostrobin; 

strobilurins do not have bactericidal properties, although they also are not 

phytotoxic to fruit), wherein copper was applied at a 42-day interval. Thus, 

reducing the frequency or copper application rate during the high-risk 

period lowered risk of copper burn. In a 2006 trial, copper burn in July was 

preceded by below average rainfall from January to June leading to drought 

conditions by mid-summer. In subsequent trials in Ft. Pierce from 2007-

2009, copper burn occurred after recurring drought conditions that ended in 

June/early July of each season. The average of the peak incidence of 

copper burn rendering fruit unacceptable to the fresh market for the three 

seasons of experimentation was a full 24 percent. Based on the severity of 

copper burn, the percentage of fruit that would be "out of grade" for 

packing is estimated at 75 percent, hence, the average reduction in packout strictly due to copper burn is estimated at 18 percent (24 X 0. 75 = 

18%}. This figure is used to calculate reduced copper burn with the use of 

FireWall in the economic analysis. 

Alternative contact bactericides such as oxytetracycline are not as effective 

as copper for canker control because they lack sufficient activity to protect 

the fruit surface. In contrast, trials conducted in Parana State, Brazii fr0r11 

2005-2007 substantiated that streptomycin in combination with red~,;cerl 

rates of copper for canker control in young groves provides comparable 

disease control to the intermediate to full rates of copper, without th~ 

phytotoxicity problem. A specific trial to establish the efficacy of anc,tht!l. 

registered "alternative", Regalia (extract of Reynoutria sachalinensis), ·..ve~s 

conducted to determine its potential for citrus canker control in a FloridJ 

east coast grove. This same trial included three formulations of cop~·P.r 

widely used for citrus canker control, for comparative purposes. Result~ 

showed that Regalia, applied at the label rate, was half as effective as tn€ 

copper treatments for reducing incidence of canker on citrus fruit (24.2% 

7 
incidence) when compared to the untreated check treatment. See 

Appendix B for this Regalia trial summary. This same study also shows that 

11 applications of Regalia (at the 1 gallon application rate), with an 

estimated $60/galjapplication, costs $660 per acre or approximately 8.5 

times the cost of a copper formulation ($?/lb./application or $77 per acre). 

The estimated on-tree revenue for fresh market Red grapefruit with citrus 

canker was $1,156 in the 2010-11 crop season when this trial was 

conducted (Ron Muraro, UF-CREC Citrus Economist, unpublished analysis). 

Therefore, the cost of Regalia alone for canker control represents 57 

percent of the on-tree profit, effectively/completely eliminating this product 

as a possible alternative whatsoever under this emergency exemption 

request. 

(ii) Alternative Control Practices: 

Local or regional eradication may be practiced to establish and maintain 

areas free of citrus canker for the planting of new orchards with cultivars of 

low to moderate susceptibility (which grapefruit is not). In an attempt to 

prohibit the introduction of the disease, many citrus-growing areas restrict 

the importation of citrus from areas or countries known to have canker. 

New groves are established only in areas without history of citrus canker for 

at least one year after effective eradication is achieved. The choice of 

planting site takes into account not only horticultural and climatic factors for 

cultivation of citrus, but minimizes environmental conditions favorable for 

the introduction of Xac and development of citrus canker. It is advised that 

sites exposed to strong winds be avoided because of the higher 

susceptibility created for the citrus trees, particularly in the early stages of 

development. 

Compliance of orchard workers with measures for thorough disinfection of 

clothes, shoes, orchard machinery and harvesting equipment including 

boxes is also essential to maintain exclusion of the pathogen. Agreements 

have been issued statewide to citrus producers in Florida requiring 

decontamination of personnel and equipment to reduce the risk of spread 

of mechanical and inadvertent human distribution of Xac. This focuse~ 

attention on the situations of greatest risk for Xacsurvival and trans.ni~!--i0n . 

To determine the possibility of survival and transmission of Xac on and from 

various surfaces, bacterial survival has been evaluated on various mat.:er:als 

including wood (representing crates, ladders, etc.), cotton cloth (clothir,y), 

cotton gloves, plastic (fruit crates), metal (vehicles, tractors, mower ~lact~s, 

etc.), leather (gloves and shoes), bird feathers and animal fur. 

Cultural practices including windbreaks and pruning or defoliation of 

diseased summer and autumn shoots are recognized throughout the ""oriJ 

as important measures for the management of citrus canker. Windbreaks 

8 
are the most effective measure for the control of the disease on susceptible 

citrus cultivars. Pruning of the citrus trees is performed during the dry 

season, when the environmental conditions are less favorable for spread of 

the bacterium from pruned to adjacent non-infected trees. However, 

pruning is very labor intensive and therefore expensive. 

In summary, alternative control practices are ineffective or insufficient for 

management of this disease. Most cultural control methods will have little 

effect on a pathogen that has already been identified across all of the 

grapefruit/citrus producing acreage of Florida. 

EFFECTIVENESS OF USE PROPOSED UNDER SECTION 18 (166.20(a)(S)) 

(166.20CalCS)) 

According to University of Florida Citrus Disease Management Specialists at the Citrus 

Research and Education Center, FireWall SOWP Fungicide/Bactericide (streptomycin) 

presents itself as the most effective chemical management tactic available to do away 

with the non-routine situation that has now arisen with respect to unacceptable levels of 

fruit phytotoxicity. In consideration of the risk of copper burn, FireWall applications made 

in 2008 and 2009 trials were timed during the July-August period when the risk of copper 

burn is the highest. In the 2008 trial, with highly favorable conditions for canker 

development before and after Tropical Storm Fay, the best treatment for reduction in 

total fruit disease incidence was two sprays of FireWall combined with a half rate of 

Kocide 3000. The reduction in total fruit disease incidence was 11.2 percent compared to 

the Kocide 3000 at the 2.0 lb/acre rate. Researchers attribute this 'best treatment" 

control to post-infection activity of FireWall against bacteria that overcame the surface 

film of copper by windblown rain mediated penetration of stomatal openings on the fruit 

surface at speed greater 18 mph (which prevailed for several hours during TS Fay). This 

control effect demonstrates that streptomycin is locally systemic in the fruit rind but that 

copper is not penetrating into the fruit rind. Local systemic activity of FireWall was 

confirmed in separate assays by measuring post-infection reduction in Xac lesions of 

populations in leaves and fruit. The additional control effect of FireWall combined with a 

half-rate of Kocide 3000 compared to Kocide was 0.8 percent in 2009, a season without a 

substantial occurrence of windblown rain events. The average additional control t!fff'rt. of 

the FireWall combined with half-rate of Kocide 3000 for the 2008 and 2009 is 6.0 

percent, the figure that is used to calculate increase in canker free fruit for pack-out 

resulting from FireWall use in the economic analysis presented later in this narrati"~. 

This added improvement to citrus canker control by FireWall was accomplished wi~hout 

the reoccurring problem of excessive, unacceptable phytotoxicity to the fruit as well. 

Additional data and information describing the effectiveness of FireWall 

Fungicide/Bactericide is included in Appendix B. 

9 
Concerns may arise pertaining to susceptibility of Xacto streptomycin. Prior to this 

Emergency Exemption request, streptomycin had not been used whatsoever in 

commercial citrus groves and the development of Xac strains resistant to this antibiotic in 

the field has not been reported. Further experimentation on this very topic has been 

conducted by University of Florida scientists, and this study has shown that even after 

three full seasons of 21-day interval streptomycin sprays (approximately 10 sprays per 

season), establishment of streptomycin resistant Xac in endemic areas is not as prone to 

occur as may have originally been presumed. Thus, since the intent is to use 

streptomycin. only twice in the season to aid with management of citrus canker, it is 

unlikely that streptomycin resistant strains will develop in Xac populations under disease 

management programs with only a few streptomycin intercalated or mixed with copper 

applications for management of citrus canker. Integrating streptomycin into the copperbased program would also possibly reduce the bacteria's selection pressure for copper as 

well. The use of streptomycin mixed with copper may aid in management of copper and 

streptomycin resistance to assure sustainability of both products for canker management 

in Florida grapefruit. Refer to the resistance analysis study included in Appendix B for 

further information and accreditation on this matter. 

DISCUSSION OF RESIDUES IN FOOD (166.20CalC6ll (166.20CalC6ll 

AgroSource, Inc. and the IR-4 Project have performing Magnitude of Residue studies for 

streptomycin sulfate in/on grapefruit. Field residue studies have been conducted and this 

information is being prepared for submission to the Agency. Based on available 

information, a temporary streptomycin tolerance of 0.2 ppm on grapefruit is proposed. 

For the dried pulp fraction, the proposed tolerance will be 1.0 ppm and for the oil and 

juice fractions the proposed tolerance is 0.005 ppm (50% of the LOQ). See the IR-4 

letter of support and the summary of the residue data, and the corresponding risk 

assessment for streptomycin on grapefruit included in Appendix B. 

DISCUSSION OF RISK INFORMATION (166.20{a){7)l 

Descriotion of application sites, including proximity to residential areas, 

aquatic systems, endangered or threatened species habitats, soil types, 

etc.: 

FireWall SOWP Fungicide/Bactericide will only be applied to commercial grapefruit 

groves. These groves are typical of those found in Florida. Commercial groves 

are intensive and no unreasonable risks to human health, endangered or 

threatened species, beneficial organisms, or the environment are expected from 

the proposed use of this product. 

10 
Possible risks posed by use: 

FireWall SOW Fungicide/Bactericide is an approved fungicide/bactericide registered 

by the U.S. Environmental Protection Agency that has been used in the field for 

more than 40 years. Possible risks were evaluated during Section 3 registration 

and reregistration processes. It is currently registered for use on crops such as 

bean seed treatments, ·celery, peppers, potatoes, tomatoes, apples and pears. No 

unreasonable adverse effects to man or the environment are anticipated with this 

proposed use of two applications of FireWall SOWP Fungicide/Bactericide to Florida 

grapefruit. Additional information on these subjects can be obtained from Taw 

Richardson from AgroSource. His phone number is (908) 215-3500. Facts 

pertaining to risk associated with the potential for increasing the risk of human 

resistance to streptomycin have been addressed in the R.E.D. Facts publication for 

streptomycin and streptomycin sulfate. That EPA report says that "regarding the 

problem of drug resistance, EPA has no data indicating that streptomycin residues 

remaining in the food supply have a significant or even a measurable potential for 

increasing human resistance to that drug." The Regulatory Conclusion of that 

same publication says that "all currently registered pesticide products containing 

streptomycin or streptomycin sulfate as the active ingredient are not likely to 

cause unreasonable adverse effects in people or the environment." EPA's 

Streptomycin R.E.D. Facts bulletin is included in Appendix B. 

Proposals to mitigate risks: 

Existing use restrictions already listed on the label will further reduce risk. These 

label restrictions include: do not apply directly to water, or to areas where surface 

water is present, or to intertidal areas below the mean high watermark; do not 

contaminate water when disposing of equipment wash water; only two 

applications of FireWall SOWP Fungicide/Bactericide are allowed per season; and, a 

prohibition for chemigation exists. Current labeling directives are sufficient to 

mitigate any potential risks. Full reports of tests and investigations made with 

respect to the safety of streptomycin, including all information pertaining to the 

methods and controls used in conducting these tests and investigations have been 

submitted and reviewed by the Agency. 

FOPA INFORMATION {OCTOBER 24, 1996 EPA LEITER) 

EPA requested that additional information be submitted with Emergency Exemption 

requests to address new risk considerations associated with requirements of the Food 

Quality Protection Act. This information has been provided to the Agency. Since this 

product is approved for other Section 3 registrations (i.e., bean seed treatment, celery, 

peppers, potatoes, tomatoes, apples and pears) an initial FQPA review has already 

occurred. 

11 
COORDINATION WITH OTHER AFFECTED FEDERAL, STATE, AND LOCAL 

AGENCIES C166.20CalC8)) 

As EPA's state lead agency, the Florida Department of Agriculture and Consumer Services 

should provide this information. 

NOTIFICATION OF REGISTRANT C166.20CalC9ll 

AgroSource, Inc. has been notified of this request. The company is supportive of this 

emergency exemption petition (see Appendix B for registrant support letter). 

DESCRIPTION OF ENFORCEMENT PROGRAM C166.20CalC10U 

As EPA's state lead agency, the Florida Department of Agriculture and Consumer Services 

should provide this information. 

REPEAT USES (166.20Ca)C11U 

The specific emergency exemption for Firewall 50WP Fungicide/Bactericide has been 

approved previously. Streptomycin applications that occurred effectively prevented 

further, unacceptable progression of the citrus canker organism and inhibited rind 

phytotoxicity. During the last year in which this registration was in place, approximately 

23,172 pounds of Firewall 50WP Fungicide/Bactericide (11,586 lbs. a.i.) was applied to 

just over 32,300 acres of Florida grapefruit for management of citrus canker. Where the 

disease was problematic, application rates and numbers of applications varied somewhat 

between growers, with most producers making an average of 1 application of Firewall 

50WP Fungicide/Bactericide at a rate of 0.6875 pounds of formulated product per acre 

per application. Where environmental conditions were conducive to citrus canker 

development, growers and university disease management specialists agree that Firewall 

50WP Fungicide/Bactericide applications were very effective in preventing disease 

development while averting damage related to heat-induced phytotoxicity on the fruit. 

No other adverse effects were reported either. 

PROGRESS TOWARD REGISTRATION C166.25(blC2lCiill 

AgroSource, in conjunction with the IR-4 Project, continues to make progress toward new 

registrations for the use of streptomycin on grapefruit and a variety of other crops. The 

company has prepared and submitted all the necessary documentation for a Section 3 

registration for grapefruit. The application to amend the Section 3 label for FireWall has 

been submitted to EPA (Decision Number: 486863) and a Pesticide Registration 

Improvement Extension Act (PRIA) due date of 05/04/2015 has been assigned. Further 

12 
information regarding progress toward registration on grapefruit can be found within 

Appendix B. 

NAME OF PEST (166.20Cb)(1)) 

Scientific Name: 

Xanthomonas axonopodis pv. Citri 

Common Name: 

Citrus Canker 

DISCUSSION OF THE EMERGENCY CONDITION (166.20(b)(2)) 

Background 

Citrus canker, caused by the bacterium Xanthomonas axonopodis pv. citri (Xac) is a leaf, 

fruit, and stem blemishing disease that affects citrus. Grapefruit, Mexican lime and some 

early oranges are highly susceptible to canker; Navel, Pineapple and Hamlin oranges, as 

well as lemons and limes are moderately susceptible; mid-season oranges, Valencias, 

tangors, tangelos and other mandarin hybrids are less susceptible; and tangerines are 

basically tolerant. Increasing international travel and trade have rendered U.S. borders 

more porous and dramatically increased the risk of introductions of invasive plant pests 

into agricultural crops. The current USDA system for protecting agricultural industries 

has been overwhelmed and has sometimes failed to intercept a number of introductions 

of exotic/invasive pests, including plant pathogens such as citrus canker. Such 

introductions threaten crops and hinder national and international agricultural markets 

and trade. Currently in Florida, one such invasive species is Xac. Citrus canker is an 

introduced plant disease, the eradication of which has received considerable press 

attention and legal challenges that has produced far-reaching political and socioeconomic 

impacts in Florida. Xacs leaf, stem and fruit-blemishing directly reduce fruit quality and 

quantity. 

Citrus canker has a long history in Florida. The disease was first found around 1912, 

spread throughout the southeastern U.S. on imported seedlings from Japan, and was 

declared eradicated from Florida and the adjacent states in 1933. Citrus canker was 

discovered again in Manatee County in 1986 and was declared eradicated in 1994. Then 

three years later the disease re-emerged in the same general area on the west coast of 

Florida where the 1980s outbreak had occurred. In the meantime, a new and separate 

infestation of citrus canker was discovered in urban Miami in 1995, with an estimated 

introduction some time in 1992 or 1993. 

13 
When detected in Miami in 1995, the infected area was contained in approximately 14 

square miles of largely residential properties southwest of the Miami International Airport. 

In response to this detection of citrus canker, a cooperative state/federal citrus canker 

eradication program (CCEP) was established between the Florida Department of 

Agriculture and Consumer Services (FDACS), the Division of Plant Industry (DPI) and the 

USDA Animal and Plant Health Inspection Service (APHIS). Concurrently, citrus canker 

was rediscovered in commercial citrus in Manatee County on the west coast of Florida in 

June 1997, where a similar eradication effort was initiated. Subsequent outbreaks of 

citrus canker have also occurred in both residential and commercial citrus in Collier, 

Hendry, Hillsborough, Palm Beach, Martin, De Soto, Monroe and Brevard counties of 

Florida whose origins are believed to be related predominantly to the inoculum reservoir 

in residential Dade and Broward counties. Despite extensive eradication efforts, which 

resulted in the removal of over 1.56 million commercial trees and nearly 600,000 infected 

and exposed dooryard citrus trees statewide, the infected area grew to 657 square miles 

as of March 2002, and now encompasses the entire state. 

In January 2000, the Florida Department of Agriculture adopted a policy of removing all 

infected trees and all citrus trees within a 1,900 foot radius of an infected tree in both 

residential areas and commercial groves. Each circle of 1,900 foot radius represents 0.41 

square miles. Previous to this eradication policy, the Department eradicated all citrus 

trees within 125 feet of an infected tree. The 1,900 foot tree removal program ended 

then in January 2006 following a statement from the USDA that eradication was 

infeasible. 

Wind-driven rain is the primary short- to medium-distance dispersal mechanism for citrus 

canker, similar to other bacterial diseases. A single drop of rainwater can carry a load of 

Xac bacteria of about 107 to 108 cells. 

Canker is a serious disease of most all commercial citrus cultivars, but grapefruit is by far 

the most susceptible variety. Severe infections can cause defoliation, blemished fruit, 

premature fruit drop, twig dieback and general tree decline. As mentioned, in 2006 

USDA researchers and officials announced that they no longer believed it was possible to 

eradicate citrus canker. Officials said that based on USDA's scientific analysis of the 

potential spread of the disease from the unprecedented 2004 and 2005 hurricane 

seasons, a new management plan must be devised. USDA said that the program needed 

to undertake a new approach that focused on maintaining bacteria at low enough levels 

to sustain citrus production and protect citrus groves that have not been infested with 

canker. This announcement came after a review of scientific research that indicated 

Hurricane Wilma may have spread the disease to the point where an estimated 168,000 

to 220,000 acres of commercial citrus was infected and exposed to canker. This was in 

addition to the more than 80,000 acres of commercial citrus that was affected by the 

2004 hurricanes. 

14 
Specific to the decrease in commercial acres of citrus present in Florida resulting from 

canker, citrus acreage reached a 20-year peak in 1996 with 857,687 acres. After that, 

acreage has declined steadily through the last census last year down to 524,640 acres, 

representing a decline of 333,047 acres or 39 percent. How much of this decline is 

directly attributable to citrus canker is unclear, but what is clear is that approximately 

87,000 acres were destroyed in the citrus canker eradication effort alone. 

On a county-by-county basis, St. Lucie County has suffered the largest decrease in the 

total acres of citrus production, with a loss of 59,151 acres between 1996 and 2008, 

representing a 55 percent decline in acreage in that County. In terms of citrus variety 

impact, the lime industry in Miami-Dade County, even though small to begin with at 

2,800 acres, was completely destroyed in the canker eradication effort. Grapefruit has 

been hit hard with a total decline from a 1996 peak of 139,200 bearing acres to 44,900 

bearing acres in 2013, a 71 percent reduction in acreage. This is due in large part to 

grapefruit's relatively high susceptibility of citrus canker compared to other varieties. 

Non-Routine Emergency Situation 

Citrus canker is an established disease that is here to stay and must now be dealt with 

continually by Florida grapefruit/citrus growers. Copper is the only bactericide registered 

for management of citrus canker. No other EPA-registered bactericides exist. 

Prophylactic/preventative bactericide applications must be made continuously, seasonlong (March through October) at approximately 21-day intervals to protect the fruit from 

canker blemish. As many as 14 applications of copper are required to protect fruit during 

this period. 

Numerous disadvantages of long-term use of copper for canker management have been 

documented, including induction of copper resistance in Xac populations and 

accumulation of copper in citrus soils with potential adverse environmental effects. As 

such, EPA has set targets for the amount of the copper .element entering citrus agroecosystems. 

The most significant disadvantage of using copper for management of citrus canker on 

grapefruit, and the reason for the development of this non-routine emergency situation, 

is the fact that now necessary application of copper before, during or after the hot 

periods of spring/summer is causing excessive/unacceptable yield reducing phytotoxicity 

to the grapefruit rinds. This phytotoxicity results when the chemical "burn" causes rind 

tissues to develop corky lesions. These lesions/blemishes make the grapefruit 

unacceptable for the fresh market. Fruit are rejected and relegated to the juice sector, 

which pays only a fraction of what would be returned had the fruit gone to fresh market 

as intended, purely because of the summer spray, copper-induced phytotoxicity. 

15 
With the development/appearance of this phytotoxicity problem on grapefruit, 

researchers immediately initiated studies attempting to seek a solution. Subsequent 

studies demonstrated that copper hydroxide and copper sulfate applied at 14- or 21-day 

intervals season long would manage canker on fruit, but in fact did cause considerable 

copper burn to the fruit rind. This research however also proved that alternation of 

streptomycin with a reduced rate of copper provided a similar reduction in diseased fruit, 

with less copper burn than the full rate of copper alone. So ultimately, this research 

determined that reducing the frequency or rate of copper application during the high risk 

summertime periods lowered the risk of copper burn to acceptable levels. Use of 

streptomycin in this manner during hot/dry periods not only reduces the rate and 

frequency of copper applications but as mentioned previously also contributes to 

management of the risk for development of bacterial resistance to either copper or 

streptomycin. 

Trials from Brazil and Florida now prove the efficacy of streptomycin and the reduction of 

risk from phytotoxicity to fruit. The University of Florida has proposed that two 

applications of streptomycin be targeted to the window of risk for copper burn during the 

season. Use of streptomycin will be limited to minimize the risk of resistance of Xac to 

streptomycin and to maintain a sufficient preharvest interval for prevention of residues in 

harvested fruit. 

A specific economic overview analyzing the impacts of citrus canker with and without the 

availability of FireWall SOWP Fungicide/Bactericide follows in the Discussion of Economic 

Loss section. 

Resistance Monitoring 

As a condition of approval for this emergency exemption request, EPA mandated that 

Florida conduct testing and field monitoring to investigate whether microbial resistance to 

streptomycin sulfate is occurring because of this use on grapefruit. A resistance 

monitoring testing and field monitoring regimen/protocol proposal was submitted to EPA 

to allow this monitoring work to commence in correlation with the anticipated use season 

for Firewall. The protocol for this resistance monitoring as well as the requested progress 

report as a part of the approval process for this year are included in Appendix B. 

DISCUSSION OF ECONOMIC LOSS C166.20CblC4ll 

In Florida, grapefruit accounted for 47,656 planted acres and a $111 million value of 

production during 2012-13. While it may be unlikely that the state will suffer 100 percent 

losses from this citrus canker,·losses from canker blemish and copper burn have been 

documented to be between 24 - 26 percent over the entire grapefruit acreage, and this 

trend can be expected to continue. No other efficacious fungicides/bactericides are 

currently registered for this pest on grapefruit or any other variety of citrus. With no 

alternative fungicides/bactericides being available and no grapefruit varieties naturally 

resistant to this disease being available for many years to come, the Florida grapefruit 

16 
industry will continue to experience a non-manageable, non-acceptable escalation of fruit 

surface burning from applications of copper. 

Grapefruit in Florida is produced with the goal of selling to the fresh market, as fresh 

market Florida grapefruit provides average returns of $11.00 dollars per box, whereas 

grapefruit that had to be turned away and sent to the juice market because of copper 

phytotoxicity on the fruit rind only provided a $2.43 per box. This represents an 

approximately 78 percent reduction in potential income, which often was the result 

primarily because of the copper-induced phytotoxicity. 

Because of these realities, losses resulting from copper burn of grapefruit are and will 

continue to be significant. With the elimination of the eradication program and the lack 

of any additional federal assistance dollars, the canker/copper burn problems associated 

with production currently are unlike any experienced to date, before the availability of 

FireWall. If growers have to deal with this situation without continued access to FireWall, 

packout losses of the magnitude possible from this situation will affect the long-term 

economic viability and sustainability of Florida's grapefruit industry. 

The foundation for this non-routine Emergency Exemption request for FireWall 

(streptomycin) on grapefruit continues to be management of citrus canker during the 

high-risk for phytotoxicity summer period, by applying a limited number of FireWall 

applications in combination with a lower rate of copper to increase disease control during 

windblown rain events while simultaneously reducing the level of copper contacting the 

susceptible fruit rind during times of hot weather. A concerted use of FireWall combined 

with copper will also minimize concern for Xac developing resistance to streptomycin or 

copper. Using the information discussed previously in this narrative, the economic 

analysis presented below for FireWall shows a substantial net revenue return of $195.42 

per acre and potential net revenue to grapefruit growers of $8,774,506 industry wide. 

17 
Summary 1. On-Tree Revenue per Acre for Florida Grapefruit and Loss Due to Endemic 

Citrus canker- 2009-2010 to 2012-2013 Production Seasons 

White Grapefruit - On-Tree Revenue 

Season Without Canker With Canker Revenue (Loss) 

($/A) ($/A) ($/A) 

2009-2010 $2,757 $1 564 ($1,192) 

2010-2011 $2,761 $1 689 ($1,072) 

2011-2012 $2,819 $2,051 ($ 786) 

2012-2013 $2,668 $1_L738 ($ 930) 

Red Grapefruit- On-Tree Revenue 

Season Without Canker With Canker Revenue (Loss) 

($/A) ($/A) ($/A) 

2009-2010 $3,398 $2 308 ($1,090) 

2010-2011 $3,129 $2,355 ($ 774) 

2011-2012 $3,246 $2 612 ($ 634) 

2012-2013 $2,630 $1,635 ($ 995) 

Summary 2. Estimated Total On-Tree Revenue Loss for Florida's Grapefruit Industry 

with Endemic Citrus Canker- 2009-2010 to 2012-2013 Production Seasons 

White Grapefruit 

Total Bearing Red Grapefruit Total 

Acreage Bearing Acreage 

Season ( 1000 Acres) (1 000 Acres) 

2009-2010 14.6 33.5 

2010-2011 14.2 32.5 

2011-2012 13.6 31.9 

2012-2013 13.0 31.9 

White Grapefruit 

Total On-Tree Red Grapefruit OnRevenue (Loss) with Tree Revenue (Loss) Total On-Tree 

Season Canker with Canker Revenue (Loss) 

($1,000 x) ($1,000 X) ($1,000 x) 

2009-2010 ($17,410) ($36 932) ($54,342) 

2010-2011 ($15,229) ($25 738) ($40,967) 

2011-2012 ($10,442) ($21,559) ($32,001) 

2012-2013 ($12,091) ($31,740) ($43,830) 

18 
Table 1. Before Citrus Canker Became Endemic in Florida -

Estimated Average Marketable Packout 

Florida Fresh Grapefruit- 2009-2010 to 2012-2013 Production Seasons 

Percent Packout* 

White Grapefruit 34.1% 

Red Grapefruit 52.0% 

*= From discussions with Florida fresh citrus packers and the Florida Citrus 

Administration Committee, 2012-13 Season Summary 

Table 2. After Citrus Canker Became Endemic in Florida -

Decrease in Average Marketable Packout 

Florida Fresh Grapefruit - Using Only Copper Chemical Control Treatment 

Percent Packout** 

Incidence of Citrus Canker Lesioned Fruit I 26.4% 

**= J.H. Graham eta. "Streptomycin and Copper Formulations for Control of Citrus 

Canker on Grapefruit." Proc. Fla. State Hort. Soc. 123:2010 

Table 3. Adjusted Average Marketable Packout 

Florida Fresh Grapefruit After Citrus Canker Became Endemic in Florida 

Percent Packout 

White Grapefruit (34.1 minus 26.4) 7.7% 

Red Grapefruit (52.0 minus 26.4) 25.6% 

Table 4. Average On-Tree Price for Fresh and Processed Market Florida Grapefruit2009-2010 to 2012-2013 Production Seasons 

White Grapefruit Fresh Market Processed Market 

Season ($/box) ($/box) 

2009-2010 $13.95 $2.96 

2010-2011 $13.20 $3.34 

2011-2012 $12.05 $4.65 

2012-2013 $12.35 j3.63 

Red Grapefruit Fresh Market Processed Market 

Season ($/box) ($/box) 

2009-2010 $12.60 $2.93 

2010-2011 $10.55 $3.73 

2011-2012 $10.40 $4.72 

2012-2013 $10.80 $1.63 

From: Florida Agricultural Statistics Service 2012-2013 Citrus Summary 

19 
Table 5. Estimated On-Tree Revenues for Florida White Grapefruit With and Without 

Endemic Citrus canker- 2009-2010 to 2012-2013 Production Seasons 

Processed Juice Total 

White Grapefruit Fresh Market Market Revenue 

On-Tree Revenue Without Boxes/Acre $/Acre Boxes/A $/Acre $/Acre 

Endemic Citrus Canker 

2009-2010 140 $1955 271 $ 802 $2 757 

2010-2011 140 $1854 272 $ 907 $2J61 

2011-2012 134 $1 615 259 $1204 $2,819 

2012-2013 138 $1,701 266 $ 966 $2,668 

Processed Juice Total 

White Grapefruit Fresh Market Market Revenue 

On-Tree Revenue With Endemic Boxes/Acre $/Acre Boxes/A $/Acre $/Acre 

Citrus Canker 

2009-2010 32 $441 379 $1,123 $1564 

2010-2011 32 $419 380 $1,270 $1689 

2011-2012 30 $365 363 $1,687 $2,051 

2012-2013 31 $384 373 $1,354 $1 738 

Table 6. Estimated On-Tree Revenue for Florida Red Grapefruit With and Without 

Endemic Citrus Canker - 2009-2010 to 2012-2013 Production Seasons 

Processed Juice Total 

Red Grapefruit Fresh Market Market Revenue 

On-Tree Revenue Without Boxes/Acre $/Acre Boxes/A $/Acre $/Acre 

Endemic Citrus Canker 

2009-2010 222 $2,798 205 $601 $3,398 

2010-2011 224 $2 359 206 $770 $3,129 

2011-2012 220 $2 288 203 $958 $3,246 

2012-2013 214 $2 308 197 $322 $2,630 

Processed Juice Total 

Red Grapefruit Fresh Market Market Revenue 

On-Tree Revenue With Endemic Boxes/Acre $/Acre Boxes/A $/Acre $/Acre 

Citrus canker 

2009-2010 109 $1,377 318 $ 931 $_2,308 

2010-2011 110 $1/161 320 $1193 $2 355 

2011-2012 108 $1126 315 $1,485 $2 612 

2012-2013 105 $1136 -306 $ 498 $1635 

20 
Table 7. Spray Costs Used in the INDIAN RIVER Citrus Production Budgets for Fresh 

Market Grapefruit- 2012-2013 

Total Pest Management Costs 

With Copper and Firewall 

With Only Copper 

Additional Cost to Add Firewall 

Table 8. Fresh Grapefruit Exports from Florida- 2012-2013 

Total Grapefruit Fresh Exports 

$/Acre 

787.33 

748.27 

39.06 

Cartons 

10.073.000 

Table 9. Estimated Percentage Increase in Packout- Marketable Florida Fresh 

Grapefruit if FIREWALL Had Been Used- 2009-2010 

Reduced Canker Blemish 

Reduced Copper Burn 

Estimated Total Increase Pack-out 

6.00% 

18.00% 

24.00% 

Table 10. Estimated Additional Cartons of Florida Fresh Grapefruit That Would Have 

Been Exported if FIREWALL Had Been Used - 2012-2013 

Cartons 

Total Grapefruit Fresh Exports (10,073,000 x 

24o/o) · 2.417.520 

Total Florida Field Box Equivalent 1.208,760 

21 
Table 11. Estimated Additional Net Revenue that Florida Growers Would Have Received 

from Fresh Grapefruit Exports IF FIREWALL Had Been Used- 2012-2013 

Grapefruit 

Total Additional F.O.B. Revenue 

Less: Processed Juice Revenue Would Have 

Received from Eliminations 

[1,208,760 boxes x (5.0 pound 

solids/box x $0.75/p.s.)] less 

$1.23/box (elimination costs) 

Additional Packing Costs 

(2,417,520 cartons x $4.77/carton) 

Additional Spray Costs 

[44,900 bearing acres x $39.06] 

Total Additional Costs 

Total Net Revenue to Growers 

Estimated Net Revenue Per 

Acre 

F.O.B. Price F.O.B. 

$/carton Revenue 

$11.00 

$ 4,532,850 

$11,531,570 

$1,753,794 

$26,592,720 

$17,818,214 

$ 8,774,506 

$195.42 

Grapefruit is the Florida citrus industry's most important fresh fruit variety with a value of 

more than $111 million in the 2012-2013 crop year. Compared with $172 million in 

2004-2005, there has been an unsustainable decrease in crop value mainly/largely 

attributable to loss of eligibility of fruit for movement to the packinghouse because of 

canker blemish and diversion of fruit to juice eliminations, loss or restriction of shipping 

to export markets, and abandonment of groves due to loss of profitability. Increasing 

declines in pack-out of grapefruit is also attributable to epidemic conditions in grapefruit 

that continue to evolve with each season. The impact of citrus canker on the citrus 

industry in Florida has been dramatic. The Federal and State Governments have spent 

over $1.4 billion on the eradication effort and to support the regulatory framework 

established after the eradication program. Management of the disease following the 

elimination of the eradication effort has been challenging. While the management 

practices recommended to the grapefruit production industry come with higher 

production costs, on a statewide basis, citrus canker has continued to spread. Finally, 

while not totally attributable to citrus canker, as previously mentioned, grapefruit 

production acreage overall in Florida have declined 71 percent, to a 20-year low during 

Florida's battle with citrus canker. 

22 
ESTIMATED REVENUES FOR THE SITES TO BE TREATED {166.2Q{b)(4)Ciil & 

Ciiil) C166.20Cb)C 4Uiil & Ciiil) 

Florida Grapefruit Production Information* 

Total Total 

Total Bearing Boxes Yield per Acre Price per On-Tree 

Season Acres (1,000 boxes**) (total boxes) Box Value 

(Millions) 

2012-13 44,900 18 350 409 $6.06 $111.1 

2011-12 44,500 18 850 414 $7.18 $135.4 

2010-11 46,500 19 750 425 $6.72 $132.7 

2009-10 48,100 20,300 422 $7.50 $152.2 

2008-09 51,900 21,700 418 $3.81 $82.7 

5-Year 

Average 47,180 19,790 418 $6.25 $122.8 

*Source: Latest Available Florida Agricultural Statistics Service Citrus Summary, March 2014. 

** Box = 85 pounds. 

Grapefruit Pricing Differential Information* 

Prices per Box (dollars) 

Season Fresh Processed Total 

2012-13 $11.00 $2.43 $6.06 

2011-12 $10.64 $4.67 $7.17 

2010-11 $10.99 $3.58 $6.72 

2009-10 $12.82 $2.94 $7.50 

2008-09 $ 8.17 $0.52 $3.81 

*Source: Latest Available Florida Agricultural Statistics Service Citrus Summary, March 2014. 

23 
Estimated net and gross revenues without the use of the proposed 

pesticide Cbut with next best alternative): 

Estimated yield, net and gross revenues for citrus without the availability of 

Firewall are computed using only conservative potential yield/packout loss values 

calculated by University of Florida field trial data. According to University of 

Florida field data, packout reductions resulting from citrus canker and copperinduced phytotoxicity are calculated to be between 24 - 26 percent (Table 2 

above) when incorporating the next best registered alternative (copper alone, 

season long) under standard summertime growing parameters. Overall, University 

data show that the net return experienced by Florida grapefruit growers when 

incorporating Firewall into the summertime citrus canker management strategy 

would be substantial at $930 per acre for white grapefruit ($2,668- $1,738 = 

$930) and $995 per acre for red grapefruit ($2,630 - $1,635 = $995) (Support 

Tables 5 and 6 above), equating to nearly $8.8 million industry-wide. 

24