BIOPESTICIDES REGISTRATION ACTION DOCUMENT

MON 89034 x TC1507 x MON 88017 x DAS-59122-7 (SmartStax®) 

B.t. Corn Seed Blend 

U.S. Environmental Protection Agency (EPA) 

 Office of Pesticide Programs 

Biopesticides and Pollution Prevention Division (BPPD) 

April 8, 2011
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Biopesticides Registration Action Document

TABLE OF CONTENTS 

I. BACKGROUND ............................................................................ 3 

II. SCIENCE ASSESSMENT ................................................................ 4 

III.REGULATORY RATIONALE......................................................... 25 

IV.TERMS AND CONDITIONS............................................................ 27 
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 I. BACKGROUND 

Active Ingredients: 

Bacillus thuringiensis Cry 1A.l05 protein and the genetic material necessary (vector 

PV-ZMIR245) for its production in corn event MON 89034 

Bacillus thuringiensis Cry2Ab2 protein and the genetic material necessary (vector 

 PV-ZMIR245) for its production in corn event MON 89034 

Bacillus thuringiensis Cry1F protein and the genetic material necessary (vector PHP8999) for its 

production in corn event TCI507 

Bacillus thuringiensis Cry3Bbl protein and the genetic material necessary (vector PV-ZMIR39) 

for its production in com event MON 88017 

Bacillus thuringiensis Cry34Ab1 protein and the genetic material necessary (vector PHP17662) 

for its production in corn event DAS-59122-7 

Bacillus thuringiensis Cry35Ab1 protein and the genetic material necessary (vector PHP I7662) 

for its production in corn event DAS-59122-7 

Trade & Other Names: 

MON 89034 x TC1507 x MON 88017 x DAS-59122-7 RIB Complete Insect Protected, 

Herbicide-Tolerant Corn 

MON 89034 x TC1507 x MON 88017 x DAS-59122-7 Insect Protected, Herbicide-Tolerant 

Corn with Interspersed Refuge 

Genuity® SmartStax® RIB Complete 

Refuge AdvancedTM Powered by SmartStax®

OPP Chemical Codes: 006490, 006481, 006502, 006515, 006514 

Type of Pesticide: Plant-Incorporated Protectants (PIPs) 

Basic Manufacturers: Monsanto Company 

800 North Lindbergh Blvd 

St. Louis, MO 63167 

Mycogen Seeds c/o Dow AgroSciences LLC 

9330 Zionsville Road 

Indianapolis, Indiana 46268-1054 
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Target Pest(s): European corn borer (ECB) 

Southwestern corn borer (SWCB) 

Southern cornstalk borer (SCSB) 

Corn earworm (CEW) 

Fall armyworm (FAW) 

Stalk borer 

Lesser corn stalk borer 

Sugarcane borer (SCB) 

Western bean cutworm (WBC) 

Black cutworm 

Western com rootworm (WCRW) 

Northern corn rootworm (NCRW) 

 Mexican corn rootworm (MCRW) 

Product Profile: 

EPA conditionally registered MON 89034 x TC1507 x MON 88017 x DAS-59122-7 in July 

2009. MON 89034 x TC1507 x MON 88017 x DAS-59122-7 is a bioengineered corn PIP 

product containing two (2) Bt PIPs active against corn rootworm (CRW) and three (3) Bt PIPs 

active against various corn borer pests. MON 89034 x TC1507 x MON 88017 x DAS-59122-7 

currently requires a combined 5% refuge for corn rootworm and lepidopteran pests where the 

corn earworm is not a significant pest and a 20% combined refuge in cotton growing regions 

where the corn earworm is a significant pest. 

MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blend products combine 95% MON 

89034 x TC1507 x MON 88017 x DAS-59122-7 corn with 5% refuge non-Bt corn. No external 

block refuge is required where the corn earworm is not a significant pest. A 20% refuge is 

required in cotton growing regions where the corn earworm is a significant pest. 

II. SCIENCE ASSESSMENT 

A. INSECT RESISTANCE MANAGEMENT 

Summary

1) Corn Rootworm 

BPPD has reviewed Monsanto’s and Dow AgroSciences’ submissions for a 5% SmartStax seed 

mixture including biological and efficacy data as well as simulation modeling. In addition, BPPD 

conducted independent modeling analyses of the applicants’ proposal using a model 

(deterministic and probabilistic) developed by EPA/ORD. After careful review of the applicants’ 

modeling and the analyses conducted by ORD, BPPD concluded that for corn rootworm (CRW), 

a 5% seed mixture and 5% structured refuge have comparable durabilities. Despite identifying a 

number of uncertainties with the CRW assessment, the FIFRA SAP (2011) verified BPPD’s 

conclusion that a 5% MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blend should 

have comparable durability to a 5% block refuge. 

2) Lepidoptera (European Corn Borer and Southwestern Corn Borer) 

Based on a review of the Science Advisory Panel (SAP) report (SAP 2011) and revised 

modeling submitted by Monsanto/Dow, BPPD concludes that a 5% seed blend for MON 89034 x 
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TC1507 x MON 88017 x DAS-59122-7 corn will likely be less durable (perhaps significantly so) 

than a comparable (5%) block refuge for the product. BPPD notes, however, that a MON 89034 

x TC1507 x MON 88017 x DAS-59122-7 5% seed blend should be more durable than a 20% 

block refuge for a single toxin Bt corn product or a comparable (5%) seed blend for a two toxin 

pyramid. Larval movement, potential survival (and selection) of heterozygote genotypes, and 

loss of refuge effectiveness during the growing season are the primary factors that are likely to 

reduce durability in seed blends. 

To improve BPPD's ability to assess the risks of resistance for a MON 89034 x TC1507 x 

MON 88017 x DAS-59122-7 seed blend, the following topics and uncertainties must be 

addressed: 

 Revised modeling incorporating the structural elements recommended by the SAP (i.e., 

explicit larval movement, switch from a frequency-based model to one including densitydependent larval mortality, epistatic mechanisms for resistance in target pests) with 

separate analyses for SWCB and ECB. Non-uniform oviposition should be modeled for 

both ECB and SWCB, especially (but not only) for the second generation of adults which 

will more likely lay eggs on Bt rather than on damaged (or crowded out) non-Bt refuge 

plants in seed blends. 

 Biological research on adult movement (related to mating and movement from refuges), 

larval movement, larval feeding (i.e., selective feeding within corn ears or on pollen), 

survival of heterozygote genotypes on MON 89034 x TC1507 x MON 88017 x DAS59122-7 (markers may need to be determined for heterozygotes), and the potential for 

epistatic mechanisms of resistance (particularly with older instars). 

Problem Formulation 

BPPD’s risk assessment focused on assessing the risk of resistance developing to a 5% MON 

89034 x TC1507 x MON 88017 x DAS-59122-7 seed mixture in three main target pests: 

European corn borer, Southwestern corn borer, and corn rootworm. The registrants proposed the 

continued use of the existing 5% structured refuge requirement for MON 89034 x TC1507 x 

MON 88017 x DAS-59122-7 in most parts of the Cotton Belt so as to not further contribute to 

the risk of resistance evolution in corn earworm (CEW). Although it is known that CEW migrate 

northward during the growing season to corn-growing regions (i.e., the U.S. Corn Belt and 

Canada), CEW typically are not capable of overwintering in these regions. Rather, CEW are 

known to overwinter in the South, often in cotton fields. Some reverse migration from the Corn 

Belt to the Cotton Belt was observed by Gould et al. 2002, which sparked interest and the need 

to quantify the impact of south-north and north-south migration on the adaptation rates in CEW. 

Computer simulations by the Agricultural Biotechnology Stewardship Technical Committee 

(ABSTC) showed no significant interaction between the percent of the late summer adult CEW 

population in the south that is made up of immigrants and the date at which migrants return and 

no effect of return migration on the resistance gene frequency. 

In the case of fall armyworm (FAW), a secondary target pest of MON 89034 x TC1507 x MON 

88017 x DAS-59122-7 in the continental US, the species distribution is currently limited to 

areas of southern Florida and southern Texas; hence FAW are not currently a corn pest in the 

regions proposed for the adoption of a 5% MON 89034 x TC1507 x MON 88017 x DAS-59122-

7 seed mixture. Should future climate change elicit a range expansion for FAW and expand its 
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overwintering capacity into the Corn Belt, then a revised risk assessment will be needed for this 

target pest and the proposed 5% MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed 

mixture. 

A. Seed Mixture vs. Structured Refuge 

Seed mixtures incorporating Bt and non Bt crop seeds have been a topic of discussion for almost 

two decades. While such an Insect Resistance Management (IRM) strategy has obvious benefits 

(i.e., no grower compliance component, facilitating the planting of Bt and refuge fields), it has 

been proposed that under some circumstances this approach could lead to more rapid evolution 

of resistance in some target pests. 

Scientific Advisory Panels (1998 and 2000) discouraged the Agency from the use of Bt seed 

mixtures to control lepidoptera target pests because substantial larval movement could be 

expected between Bt and non-Bt plants leading to more rapid selection of resistance. Conversely, 

the 2009 SAP concluded that a 20% seed blend strategy for Bt corn with low- or medium-dose 

effects on corn rootworm (Coleoptera: Chrysomelidae) was supported by the insect’s limited 

larval movement. But the SAP specifically noted that this recommendation should not set a 

precedent for other Bt crops targeting other pests (SAP 2009). 

Theoretical work by Mallet and Porter (1992) showed that insect resistance was accelerated in 

seed mixtures compared to Bt stands where 10% of the population was not exposed to selection, 

when the probability of larval movement ranged from intermediate to high (≥ 0.2), intensity of 

selection was great, and dominance of the resistance gene was low. They also reported that when 

insects selectively chose their food source (avoidance of toxic substances), then effective 

dominance was increased, and seed mixtures could delay resistance evolution but that predicted 

outcomes depended also on other circumstances. 

Using Mallet and Porter’s model, Tabashnik (1994) reported that 10% Bt seed mixtures were 

more durable than pure Bt stands and that block refuges of 10% were at least as durable (and 

more) as 10% seed mixtures when inheritance of resistance was recessive, partly recessive, or 

additive. As the percentage of refuge increased from 0-50%, Tabashnik further reported that a 

block refuge strategy performed equally well or better than seed mixtures. Seed mixtures in 

conjunction with refuges were the most durable of all deployment strategies evaluated. 

Onstad and Gould (1998) recommended 20% block refuges adjacent to the Bt fields over seed 

blend strategies because of uncertainties surrounding expression of high-dose against the target 

pest. Their modeling results predicted that block refuges would be more durable than seed 

mixtures aimed at controlling lepidopteran pests. 

 

In a 2-yr field study with a seed mixture expressing Cry1Ab and non-Bt corn, Davis and Onstad 

(2000) obtained larval dispersal data, which were used to parameterize their simulation model 

and assess the effect on the durability of seed mixtures. Davis and Onstad observed that survival 

(after recovery) was lower for larvae that successfully dispersed from Bt to non-Bt plants 

compared to larvae that dispersed from non-Bt to non-Bt plants; this should favor heterozygote 

genotypes and make inheritance of resistance less recessive (Mallet and Porter 1992). In 

addition, increased mortality of susceptible larvae moving off refuge plants onto Bt plants would 

result in a reduced effective refuge. They reported that neonate dispersal away from Bt plants 

was greater than dispersal observed from non-Bt plants and noted that extensive use of seed 
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mixtures could select for populations with improved dispersal capabilities. The empirical data 

was used to parameterize the simulation model (Onstad and Gould, 1998), and it was determined 

that while seed mixtures delay evolution of resistance in ECB they are less effective at doing so 

than IRM strategies using a 20% block refuge. 

Carierre et al. (2004) concluded that the differences in Bt trait durability predicted by block 

refuges and seed mixtures in Mallet and Porter (1992) and Tabashnik (1994) were caused by a 

reduction in refuge insects in seed mixtures that had moved from non-Bt plants to Bt plants and 

could be overcome if the percent of non-Bt plants in seed mixtures was increased (compared to 

blocks). 

B. Uncertainties 

BPPD’s assessment (BPPD 2010) of Monsanto and DowAgroScience’s proposal identified a 

number of uncertainties regarding the biology of the target pests and potential impacts on a seed 

blend strategy. 

1. BPPD recognizes that to determine whether a 5% seed mixture (both lepidoptera and 

coleopteran controlling agents) is a superior, equivalent, or inferior strategy to the 

currently approved 5% block refuge for MON 89034 x TC1507 x MON 88017 x DAS59122-7, a number of uncertainties and questions need to be considered. 

2. There is evidence that some fraction of the adult ECB population may take part in longdistance dispersal (references described above) and that this behavior is a normal part 

of ECB life-history. Evidence suggests that these insects are able to cover more than 12 

km in one flight attempt. Results by Dorhout et al (2008) suggest that a fraction of 1-d 

old females appear to engage in obligate migratory flights. Mark-recapture studies in 

aggregation sites have failed to collect more than 1% of the released individuals. To 

determine whether a structured refuge some distance away from the Bt field or an 

integrated refuge via seed blend is the better IRM option for ECB, information with 

respect to the proportion of the population engaging in obligate migratory behavior and 

timing of mating with respect to dispersal is crucial. 

3. The proportion of the female ECB population that would have to engage in preovipositional long distance dispersal before durability of a 5% MON 89034 x TC1507 x 

MON 88017 x DAS-59122-7 seed mixture became compromised and whether that 

proportion would be a reasonable assumption is uncertain. 

4. When susceptible ECB larvae move from Bt plants to non-Bt plants and their survival 

is lowered compared to susceptible larvae that have not previously been exposed to Bt 

(Onstad & Gould 1998), then a seed mixture can be expected to decrease the effective 

refuge. Likewise, if susceptible larvae leave non-Bt plants, arrive on Bt plants, and are 

subsequently killed, then seed mixtures can be expected to reduce the refuge population 

to less than what can be expected to emerge from a block refuge. In either case, 

literature supports that such conditions would increase the risk of resistance evolution 

in the target pests. An assessment is needed of whether the reduction in effective refuge 

is substantial and could reduce the overall durability of the Bt product. 
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5. Based on the timing of mating for SWCB (within 24-48h) and the pre-copulatory flight 

behavior over natal fields by males, it has been suggested that random mating occurs in 

the field for this target pest. Results by Qureshi et al. (2006), however, suggest that 

SWCB are also capable of dispersing greater distances. Based on the limited studies 

available in the public literature, it appears that mating could primarily take place in 

natal fields but that greater dispersal may also occur after the mating phase. Whether 

mating occurs before or after dispersal or whether only a fraction of females disperse 

during the pre-mating phase is important information and can impact the recommended 

IRM approach. 

6. There may be regions in the continental U.S. where the Cotton Belt and Corn Belt 

overlap and where corn earworm is known to overwinter. Such potential areas must be 

identified because they could contribute to increased selection in corn earworm (CEW - 

aka cotton bollworm, CBW), which is a main target pest of both cotton and corn. 

7. A reduction in male CRW in Bt mixtures was discussed by the SAP (2009) with respect 

to 5% Cry34/35 Bt corn mixtures. The SAP (2009) concluded that a reduction in the 

number of males could negatively affect refuge effectiveness. This concern also applies 

for the pyramided Bt corn mixture targeting CRW and should be addressed. 

8. Different types of events and behaviors have been documented to affect WCRW adults’ 

dispersal spatially and temporally in the US Corn Belt. Despite this additional evidence 

for long distance dispersal, some data gaps still exist and should be addressed so that 

dispersal can be best incorporated into simulation models. For example, Spencer (2009) 

reported that individuals of the variant WCRW type dispersed more than 200 m/day; 

however, the proportion of individuals in a population undertaking this sort of long 

distance movement is unknown. Likewise, uncertainties associated with proportion of 

populations dispersing during cold front events (wind speeds of > 1.5 m/s) and 

frequencies of such events make it challenging to include this mode of dispersal. 

9. It is unclear what proportion of female CRW populations would have to engage in preovipositional long distance dispersal before durability of a 5% SS seed mixture could 

potentially be compromised. 

10. It is unclear how non-compliance will affect the durability of a 5% block refuge relative 

to a 5% seed blend and whether such non-compliance assumptions are reasonable for 

the US. 

Corn Rootworm Assessment 

BPPD reviewed Monsanto’s and Dow AgroSciences’ submissions for a 5% MON 89034 x 

TC1507 x MON 88017 x DAS-59122-7 seed mixture including biological and efficacy data as 

well as simulation modeling (BPPD 2010). In addition, BPPD conducted independent modeling 

analyses of the applicants’ proposal using a model (deterministic and probabilistic) developed by 

EPA/ORD. After careful review of the applicants’ modeling and the analyses conducted by 

ORD, BPPD concludes that or corn rootworm (CRW), a 5% seed mixture and 5% structured 

refuge have comparable durabilities; 

Monsanto Company and Dow AgroSciences separately submitted efficacy, adult emergence, and 
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larval movement data, which served to support some of their assumptions made in their 

simulation models. The modeling analyses focused on the time to resistance or ‘rate of 

adaptation’ for European corn borer, Southwestern corn borer, and corn rootworm from the use 

of a 5% MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed mixture (95% Bt and 5% 

non-Bt seed). Dow’s model predicted similar increases in corn rootworm resistance allele 

frequencies for both refuge strategies, while 

EPA/ORD’s simulation analyses were conducted separately for CRW and ECB/SWCB using a 

two-locus deterministic and probabilistic model, which is an extension of the model used in 

Caprio and Glaser (2010a). The analysis was conducted by running 1000 simulations, each time 

re-sampling a group of uncertain parameters using a PERT- Beta distribution (setting a 

minimum, most likely, and maximum value for each parameter of concern). For each pest, the 

model output generated a probability distribution for durability (time to resistance) based on the 

1000 simulations that were conducted. To analyze these distributions, BPPD established 

durability estimates for various levels of risk (i.e., the likelihood that a resistance event would 

occur within a particular timeframe). For example, a 5% level of risk would mean that in 95% of 

the simulations, resistance evolved in greater time than the durability estimate predicted. 

Conversely, in the other 5% of the simulations resistance developed within the predicted time 

frame. 

In the CRW model simulations (see Table 1), the mean time to resistance was 82 years for a 5% 

seed blend and 53 years for a 5% structured refuge. As described above, a probability 

distribution was also created from the simulations for the estimated time to resistance with a seed 

blend and structured refuge. With a 5% level of risk, the durability of MON 89034 x TC1507 x 

MON 88017 x DAS-59122-7 seed for CRW was 33 years, while the block refuge was 22 years. 

 This means that in only 5% of the 1000 simulations conducted, resistance evolved within 33 

years (seed blend) and 22 years (structured refuge). 

Table 1. Durability estimates by EPA/ORD and Dow for 5% SmartStax seed mixture and 5% structured 

refuge targeting Corn rootworm 

1

 For benchmark and worst-case assumptions 

2

 Dow’s model predicted similar durability for SmartStax under both refuge scenarios but no actual values were provided. 

FIFRA Scientific Advisory Panel

The Agency held a Scientific Advisory Panel meeting on December 8-9, 2010 to address 

BPPD’s risk assessment of 5% MON 89034 x TC1507 x MON 88017 x DAS-59122-7, a multitoxin double pyramid targeting above ground (Lepidoptera) and below ground (Coleoptera) pests 

of maize. In the Agency’s risk assessment, BPPD evaluated Monsanto’s modeling for 

Lepidoptera pests and Dow’s modeling for corn rootworm; additionally, BPPD collaborated with 

EPA/ORD in an independent modeling effort to evaluate the applicants’ proposal (BPPD 2010). 

The SAP provided its written report to the Agency on March 3, 2011.

Refuge Scenario 

Dow CRW Model ORD CRW model 

Increase in Resistance Allele 

Frequency1 5% Level of Risk Average Years 

5% Seed Blend Similar rates of increase2

 for the 

20 years modeled 

33 years 81.9 years 

5% Structured Refuge 22 years 52.9 years 
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Lepidopteran Assessment (ECB, SWCB, CEW)

The SAP expressed concern about the risk of resistance by the European corn borer (ECB) and 

southwestern corn borer (SWCB) in a 5% MON 89034 x TC1507 x MON 88017 x DAS-59122-

7 seed blend compared to a 5% structured refuge (approved by the Agency in 2009). Their 

overall conclusion was that a 5% MON 89034 x TC1507 x MON 88017 x DAS-59122-7 

strategy would be substantially less durable than a 5% MON 89034 x TC1507 x MON 88017 x 

DAS-59122-7 (SSX) structured refuge and that there was “insufficient scientific basis for 

supporting the SSX RIB as an effective IRM strategy” for ECB and SWCB. The following is a 

summary of the SAP’s main concerns about Monsanto’s assumptions and parameter values 

chosen in their model for European corn borer and southwestern corn borer: 

A. Structural equations to model larval movement were not included in the model, and the 

approximations used by the applicant were structured to minimize the effect of larval 

movement on the rate of resistance evolution. The durability of 5% SSX RIB was 

overestimated by modeling larval movement implicitly and by not considering different 

larval-movement hypotheses (NBI, NBP, BNI, and BNP). Larval movement in Bt/non-Bt 

seed mixtures may lead to greater heterozygote survival, which in turn would speed up 

resistance evolution. 

B. No cross-resistance was incorporated into the model between Cry1F and Cry1A.105 and 

Cry2Ab when the applicants’ data (Schlenz et al. 2008) indicated some level of epistasis 

and cross-resistance between Cry1F and the other two toxins. 

C. Other forms of epistasis (expression of a gene is suppressed by a gene at another locus) 

were not considered; rather the applicant assumed that survival of genotypes was 

multiplicative for all three loci (least conservative assumption because heterozygote 

survival was, therefore, low). Other forms of epistasis should have been explored for 

ECB and SWCB such as, for example (but not only), “developmentally restricted 

expression of low levels of Cry-protease where older larvae survive Bt exposure when 

moving from non-Bt onto Bt”. Additionally, resistance at all loci could be determined by 

the most rapidly evolving locus, which could drag other resistant loci along and, thereby, 

increase the rate of resistance evolution. 

 

D. Non-uniform oviposition of 2nd generation ECB and SWCB in seed blends should favor 

Bt plants because adult females could distinguish between damaged (non-Bt) and 

protected (Bt) plants. This selective oviposition behavior based on unsuitable non-Bt host 

plants will reduce the effective refuge in a seed blend compared to a structured refuge. 

For 1st generation ECB and SWCB, non-uniform oviposition is also a probability, 

especially when the refuge plants incurred root damage from corn rootworm (CRW) and 

subsequently experience crowding out by faster growing (CRW protected) Bt plants. 

E. Strong density-dependence occurs in SWCB, and this aspect was not incorporated into 

the applicant’s model to estimate resistance evolution. “Soft selection” might be 

operating in this species in contrast to viability selection; “larvae that win out in 

cannibalistic encounters in the presence of Bt are likely to be those that have a slight 

fitness advantage from being more resistant to Bt”. 
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F. The Panel recommended that emphasis in modeling assessments of stacked cultivars 

should be placed on durability for the pest that shows the greatest potential rate of 

resistance evolution. The Panel suspected that this may be SWCB for MON 89034 x 

TC1507 x MON 88017 x DAS-59122-7 

G. For corn earworm and SSX RIB, the panel concluded that there were serious risks to both 

cotton and corn due to pollination concerns of corn ears in a seed blend environment. The 

panel was unable to quantify the role of selection on the rate of resistance evolution in 

CEW associated with a SSX RIB in the Corn Belt and migration between the northern 

corn growing and southern cotton growing regions at the time. 

The panel suggested that the current industry and EPA models be revised (or new models 

created) to address the factors that led to overestimates of durability. In particular, the panel 

recommended that new modeling focus on improving the parameters for survival of genotypes 

(especially heterozygotes) in a pyramided toxin environment. Further, the panel indicated that 

modeling on a regional scale may be suitable to investigate the effects of region-wide pest 

population suppression from a seed blend deployment. 

The panel recommended additional research regarding dispersal/movement of adults, effects of 

plant-to-plant movement on larvae, survival of different genotypes on Bt toxins (particularly 

heterozygotes), and effects of kernel pollination effects on corn earworm (CEW) refuge. 

The panel suggested that seed blends could be implemented with a phase-in approach in which 

the seed blend percentage was lowered as data were developed (i.e., resistance monitoring and 

population density). No specific blend percentage numbers were recommended by the panel for 

this approach. It was also suggested that the resistance management plan have a well-defined 

trigger for remedial action (in the event that resistance develops). 

Corn Rootworm Assessment

For corn rootworm, the SAP concluded that seed blend and block durability for SSX would be 

comparable. 

BPPD Review of Monsanto/Dow’s Submission Responding to the SAP Report 

Monsanto and Dow AgroSciences addressed the SAP’s concerns and submitted a written 

response to BPPD. As part of this response, Monsanto and Dow AgroSciences conducted revised 

modeling to evaluate the proposed seed blend (MRID No. 484234-01). 

The applicants agreed with the SAP’s conclusion that a 5% SSX RIB would be less durable than 

a 5% SSX with a structured refuge, they noted however that when realistic levels of noncompliance were incorporated, this difference in durability was reduced. BPPD concurs with 

this statement and notes that the SAP did not appear to address compliance in their model. 

After reviewing the Monsanto/Dow submission, (BPPD 2011) BPPD concludes that a seed blend 

expressing (such as MON 89034 x TC1507 x MON 88017 x DAS-59122-7 ) three high-efficacy 

toxins (against mobile lepidoptera pests) with low potential for cross-resistance and low risk for 

other epistatic effects should generally be more durable than a seed blend expressing two highefficacy toxins with low or no epistatic effects. For MON 89034 x TC1507 x MON 88017 x 
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DAS-59122-7, however, the relative difference in durability between a seed blend and a block 

refuge of equivalent size cannot be quantified until Monsanto and Dow address the SAP’s 

modeling recommendations (i.e., explicit larval movement, epistasis, non-uniform oviposition in 

seed blends, and density-dependent effects) and other concerns described in this review. 

BPPD noted that Dow compared the pyramided seed blend strategy solely to the single PIP with 

a 20% block refuge and showed that (under their modeling construct) the pyramided product was 

more durable than the single PIP. As stated by the SAP, a comparison between a pyramid and a 

20% single trait structured refuge should always show that the pyramid is more durable. The 

relative comparison, however, is important between single PIP, pyramided PIP (SSX RIB), and 

the pyramided PIP with a structured refuge. Monsanto included a comparison between the three 

IRM strategies and reported that a 5% SSX seed blend would be more durable than a single gene 

product with a 20% refuge and SSX with a 5% structured refuge with 50% grower noncompliance but somewhat less durable than SSX with a 5% structured refuge and 100% 

compliance. BPPD concludes that a comparison between the seed blend and a structured refuge 

with realistic numbers of non-compliance (i.e. 20%-30%, based on surveys conducted by the 

Agricultural Biotechnology Stewardship Technical Committee) would have improved their 

analysis. In addition, Monsanto could have used a probability approach to modeling noncompliance with the mean as 20% and worst-case and best-case choice for min and max values. 

The durability of block refuges should be higher with less non-compliance. 

BPPD agrees with the applicants that some of the dose profiles chosen in the SAP’s modeling 

analysis of SSX RIB were lower than what the applicants’ empirical data and published literature 

supported. It is likely that higher dose values would improve overall durability for both blocks 

and blends. 

BPPD’s review of the specific concerns raised by the SAP (and Monsanto/Dow’s response) is 

detailed below: 

A. LARVAL MOVEMENT: 

Explicit larval movement: 

BPPD concludes that Monsanto and Dow did not directly address the SAP’s recommendation to 

include explicit larval movement into their model. Instead, Dow and Monsanto provided the 

Agency with supplemental modeling in their response to the SAP report that (as in the previous 

modeling) used a spatially implicit model to estimate SSX RIB durability. Hence, both 

applicants have likely overestimated the durability of a MON 89034 x TC1507 x MON 88017 x 

DAS-59122-7 seed blend as was done in the initial modeling (see BPPD 2010 and SAP 2011). 

Larval movement hypotheses: 

The SAP also recommended that the applicants incorporate different larval movement 

hypotheses into their model. BPPD found that the applicants did not address this 

recommendation either, presumably because their field data did not support high larval 

movement and survival or maybe because of limitations with their current model structure. 

BPPD notes, however, that in their preliminary efficacy study (one season, two locations; MRID 

479437-01 (Appendix 3)) Monsanto and Dow reported that there was some degree of damage in 
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pure stand MON 89034 x TC1507 x MON 88017 x DAS-59122-7 and MON89034 x TC1507 

plots and some SWCB larvae were found (unclear how many), although significantly less than 

what was observed in 90% and 95% seed blend plots with MON89034 x TC1507. Hence, to add 

additional conservatism to their analysis, BPPD recommends that Monsanto follow the SAPs 

advice and incorporate different larval movement hypotheses into their model for SSX RIB. 

B. EPISTASIS 

Cross-resistance: The applicants addressed epistasis by incorporating various degrees of crossresistance into their new modeling submission using Dow’s deterministic, spatially implicit 

model. The applicants were able to demonstrate that durability of SSX RIB declined greatly 

initially and then somewhat slower as the degree of cross-resistance increased. With an 

assumption of 5% cross-resistance the estimated durability decreased from >> 1000 generations 

(RAF was 0.008 at 1000 gen) to 387. BPPD notes that this is a drastic drop in durability. 

Although the applicants appear to argue that the potential for cross-resistance is non-existent or 

minimal, BPPD concludes that based on the SAP’s recommendations, a small degree of crossresistance should be included in the simulations to create a more conservative model. 

Other forms of epistasis: The applicants argued that epistasis via a Cry-protease mechanism and 

altered expression of receptor genes were unlikely to be of relevance because such mechanisms 

would provide little or no selective advantage to ECB feeding on the three high-dose Bt proteins 

in MON 89034 x TC1507 x MON 88017 x DAS-59122-7 . BPPD is not convinced of the 

applicants’ argument for not including other forms of epistasis such as, for example, a Cryprotease mechanism. The SAP stated that a Cry-protease could potentially “degrade multiple Cry 

toxins, reducing or eliminating their toxicity to the insects”. The SAP also stated that it is more 

likely that Cry-protease expression occurs in later instars of ECB and SWCB, which would 

affect their fitness in a seed mixture when plant-to-plant movement occurred. If such a 

mechanism confers the ability to tolerate multiple Bt toxins and has genetic heritability, then it 

should be a “selectable” trait in an environment with significant amounts of Bt corn (SSX). 

Hence, BPPD recommends that the applicants consider including such a mechanism for older 

instars of ECB and SWCB in their model. 

 

C. NON-UNIFORM OVIPOSITION 

The applicants did not address the SAP’s recommendation regarding non-uniform oviposition in 

seed blends. The Panel stated that: 1) in seed blends of SSX, refuge plants might incur root 

damage from CRW (and other tissue damage from ECB), which could stunt their growth and 

allow protected SSX plant to effectively crowd out refuge plants. First generation females would 

then be more likely to oviposit onto SSX plants in seed blends than non-Bt plants; and 2) in a 

seed blend environment, second generation females could discriminate between damaged (nonBt) and non-damaged (Bt protected) plants and could, therefore, be more likely to oviposit onto 

Bt plants than they would otherwise. Hence, BPPD recommends that the applicants incorporate a 

degree of non-uniform ovipositing behavior by both first and second generation females favoring 

Bt plants. This would reduce the seed blend durability due to a reduction in effective refuge 

compared to a structured refuge of comparable non-Bt proportion. 

D. DENSITY-DEPENDENCE FOR SWCB 

BPPD disagrees with Monsanto and Dow’s justification (lack of movement onto and SWCB 

larval presence on SSX) for not addressing density-dependence in their model. As stated in 
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section 2.1 above, some SWCB larvae were found in pure stand SSX and MON 89034 x TC1507 

plots and seed blend plots. Hence there is evidence for larval establishment on and movement 

onto SSX plants. BPPD recommends that the applicants incorporate density-dependence into 

their simulation models as was recommended by the SAP (2011) 

E. IRM EMPHASIS ON SPECIES AT GREATEST RISK OF EVOLVING RESISTANCE 

The SAP concluded that IRM strategies should be designed around the pest that shows the 

greatest potential rate of resistance evolution. The Panel suspected that this might be SWCB for 

MON 89034 x TC1507 x MON 88017 x DAS-59122-7 . Should the applicants conduct new 

modeling incorporating BPPD’s recommendations as outlined in this review, a separate analysis 

should be provided for ECB and SWCB (as was done in the original submission -- discussed in 

BPPD 2010).

Overall Lepidopteran Pest Conclusions 

 Based on a review of the Science Advisory Panel (SAP) report (SAP 2011) and revised 

modeling submitted by Monsanto/Dow, BPPD concludes that a 5% seed blend for MON 

89034 x TC1507 x MON 88017 x DAS-59122-7 corn will likely be less durable 

(perhaps significantly so) than a comparable (5%) block refuge for the product. BPPD 

notes, however, that a MON 89034 x TC1507 x MON 88017 x DAS-59122-7 5% seed 

blend should be more durable than a 20% block refuge for a single toxin Bt corn product 

or a comparable (5%) seed blend for a two toxin pyramid. Larval movement, potential 

survival (and selection) of heterozygote genotypes, and loss of refuge effectiveness 

during the growing season are the primary factors that are likely to reduce durability in 

seed blends. 

 BPPD has major reservations regarding the modeling approaches taken by Monsanto and 

Dow (in separate models) to evaluate the MON 89034 x TC1507 x MON 88017 x DAS59122-7 seed blend. Monsanto and Dow addressed larval movement implicitly (as 

opposed to explicitly as recommended by the SAP) and did not incorporate other 

important recommendations made by the SAP (i.e., epistatic resistance mechanisms, 

density-dependent effects). As detailed in the SAP report, this approach is likely to result 

in overestimates of durability. For this reason, BPPD is unable to quantify the relative 

differences in durability estimates between refuge options (i.e., 5% MON 89034 x 

TC1507 x MON 88017 x DAS-59122-7 seed blend, 5% MON 89034 x TC1507 x MON 

88017 x DAS-59122-7 block refuge, and 20% single toxin block refuge). 

 Despite the modeling uncertainties described above, BPPD believes that, in general, a 

three toxin product such as MON 89034 x TC1507 x MON 88017 x DAS-59122-7 

should have greater durability than Bt corn products with two or fewer toxins and 

comparable refuge deployment. In other words, a three toxin seed blend can be expected 

to be more durable than a two toxin product with the same blend percentage. Similarly, a 

block refuge for a three toxin product should be more durable than the same block refuge 

for a two toxin product. This conclusion assumes that the three toxins have high efficacy 

and low cross-resistance potential. BPPD cautions, however, that the relative gain and 

loss in durability with multi-toxin pyramids should be evaluated on a case-by-case basis 

with product-specific data. 

 BPPD agrees with Monsanto/Dow that the SAP's modeling analysis 1) did not include 

three toxins for lepidoptera (two toxins were modeled for simplicity), 2) incorporated low 

dose scenarios for the toxins in MON 89034 x TC1507 x MON 88017 x DAS-59122-7 , 
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and 3) neglected to consider effects of non-compliance on block refuge. The first two 

factors likely resulted in lower durability estimates for both block and blended refuge; the 

third probably led to an overestimate of durability for block refuges. Monsanto and 

Dow's revised modeling addressed these three components. 

 Block refuges and seed mixes present different potential risks and benefits for resistance 

management. A summary of these factors is described below: 

Block Refuges 

o Pros: 

 Greater durability than other refuge approaches (including seed mixes, strip 

refuges, and natural refuge) in simulation models; 

 Allows for high production of susceptible insects; 

 Refuges can be managed to preserve yield. 

o Cons: 

 Random mating may be less likely than with seed mixes or strip refuges if adult 

movement is limited (though not the case for mobile lepidoptera); 

 Compliance must be monitored (i.e., with a compliance assurance plan); 

 Non-compliance can result in no refuge deployment or inadequate refuge 

distance from Bt field to assure random mating (more important for high-dose 

PIPs such as in MON 89034 x TC1507 x MON 88017 x DAS-59122-7 ), which 

can increase the risk of resistance; 

 Refuge may need to be treated with insecticides (potential economic and 

environmental costs); 

 There have been reports of a lack of available refuge seed in some areas; 

 Planting refuges can incur inconveniences and expenses for growers. 

Seed Blends 

o Pros: 

 Non-compliance is not an issue -- all seed bags are assumed to have the same 

amount of refuge seed (± standard error); 

 A compliance monitoring program should not be necessary (cost/resource 

savings); 

 No separate refuge management and insecticide use are needed; 

 Ease of use for growers. 

o Cons: 

 Lower durability (perhaps substantially) than block refuges in simulation 

modeling; 

 Potentially lower “effective” refuge due to damage to non-Bt plants and/or Bt 

pollination within the growing season, reduced larval movement from Bt onto 

non-Bt plants, and within-plant density-dependent mortality; 

 Possible yield loss due to lodging of refuge plants within the Bt field, particularly 

with higher (>10%) blend percentages; 

 Difficulty detecting “unexpected pest damage” (a key component of resistance 

monitoring); 

 Increased risk of resistance for pests with greater adult dispersal and larval plantto-plant movement (driven by heterozygous genotypes). 

Necessary Additional Information: 
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To improve BPPD's ability to assess the risks of resistance for a MON 89034 x TC1507 x MON 

88017 x DAS-59122-7 seed blend, Monsanto and Dow need to address the following topics and 

uncertainties: 

 Revised modeling incorporating the structural elements recommended by the SAP (i.e., 

explicit larval movement, switch from a frequency-based model to one including densitydependent larval mortality, epistatic mechanisms for resistance in target pests) with 

separate analyses for SWCB and ECB. Non-uniform oviposition should be modeled for 

both ECB and SWCB, especially (but not only) for the second generation of adults which 

will more likely lay eggs on Bt rather than on damaged (or crowded out) non-Bt refuge 

plants in seed blends. 

 Biological research on adult movement (related to mating and movement from refuges), 

larval movement, larval feeding (i.e., selective feeding within corn ears or on pollen), 

survival of heterozygote genotypes on MON 89034 x TC1507 x MON 88017 x DAS59122-7 (markers may need to be determined for heterozygotes), and the potential for 

epistatic mechanisms of resistance (particularly with older instars). 

Seed Blending –Manufacturing Considerations

1) Distribution of MON 89034 x TC1507 x MON 88017 x DAS-59122-7 and Refuge 

Seeds in the Blend

Monsanto and Dow AgroSciences Position

Monsanto and Dow AgroSciences claim that a uniform in-field distribution of refuge (non-Bt) 

plants represents the worst case scenario for IRM and that any degree of clumping of refuge 

plants will tend to reduce the potential negative impacts of seed blends. 

With a uniform distribution of refuge plants in a 5% MON 89034 x TC1507 x MON 88017 x 

DAS-59122-7 seed blend, all non-Bt plants will be surrounded by Bt plants. Hence, larvae 

moving from refuge plants onto neighboring plants will survive on a Bt plant (causing a 

reduction in effective refuge in seed blends compared to structured refuges of equivalent size). 

Conversely, larvae moving off Bt plants will have a 5% probability of arriving on a refuge plant 

(which may introduce the potential for sublethal effects from prior Bt exposure). 

A clumped distribution of refuge plants have the effect that some larvae moving off refuge plants 

will arrive on other refuge plants and, therefore, be more likely to survive than those moving 

from refuge plants onto surrounding Bt plants in a uniform distribution. In addition, larvae 

moving off Bt plants in seed blend with a clumped distribution would have less than a 5% 

probability of arriving on a refuge plant; this smaller proportion may receive sublethal exposure 

and thus there would be less differential selection of heterozygotes with a clumped versus 

uniform in-field refuge. 

The in-field block refuge scenarios (with 100% compliance) modeled by Monsanto, Dow, and 

EPA ORO represent the extreme end of the clumped scenario (i.e. minimal larval movement 

between refuge and Bt plants, highest effective refuge size, lowest relative fitness of 

heterozygotes). These modeling efforts support that clumped (or block) refuges delay resistance 

more compared to uniform distributed refuge plants in seed blends. 
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BPPD Conclusion

BPPD has reviewed Dow's and Monsanto's argument that a seed blend with a uniform 

distribution represents a worst-case scenario for IRM. BPPD concurs that clumping of refuge 

plants should be better for IRM than a uniform distribution because of an increase in effective 

refuge and decreased differential selection on heterozygotes (as stated by the applicants), which 

makes inheritance of resistance more recessive (Maliet and Porter 1992; Davis and Onstad 

2000). In cases, however, where greater asymmetrical dispersal (from Bt to non-Bt) is observed 

or expected, seed mixtures may prove to be more durable than structured refuges. 

European com borer (ECB) and southwestern com borer (SWCB) are the two main target pests 

of MON 89034 x TC1507 x MON 88017 x DAS-59122-7 in the Com Belt. With respect to 

asymmetrical movement, Onstad and Gould (199l) modeled dispersal of neonate ECB (55-

genotypes) off Bt plants with a 98% probability and off non-Bt plants with a 90% probability. 

Their data indicate that there is little asymmetrical dispersal between the two plant types. For 

SWCB, no data on differential dispersal are available in the public literature. Because SWCB is 

cannibalistic, such behavior should increase the probability of dispersal compared to ECB 

(FIFRA SAP 2011). BPPD notes that it may, therefore, be assumed that there is no great 

dispersal differential between neonates leaving Bt or non-Bt plants in response to some 

asymmetrical dispersal. BPPD concludes that for ECB and SWCB it may be safe to assume that 

a 5% MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blend with a uniform 

distribution represents a worse case than a blend with a clumped distribution. 

2) Blended Refuge Percentage Assurance 

Both Monsanto and Dow submitted data adequately demonstrating a minimum 5% refuge of 

non-Bt seed in the MON 89034 x TC1507 x MON 88017 x DAS-59122-7 blends produced at 

seed processors within their company. 

BPPD has reviewed the information provided regarding the manufacturing process in Monsanto 

and Dow AgroSciences owned facilities and concludes that: 

• The seed weighing technology should guarantee high accuracy around the determined 

target (mean weight or mean percentage) with very low expected variance provided that 

all of Monsanto's Dow’s manufacturing plants maintain and follow the same procedures respectively; 

• The seed mixing technology will be set to satisfy growers expectation of uniformity but 

some degree of clumping of refuge seed may be possible. BPPD does not expect clumping of refuge 

plants in the field to impact lRM for ECB and SWCB (see BPPD 2011) because of very little 

expected asymmetrical movement between the two plant types (Bt and non-Bt) for both species as 

supported by Onstad and Gould (1998); 

• Bt and refuge seed will be colored differently when seed blends are mixed in Monsanto or Dow 

AgroSciences owned manufacturing plants. Monsanto is also encouraging its seed company licensees 

to color the Bt and refuge seed differently. Coloring the two types of seed differently will provide an 

additional affirmation that the product is in fact a seed blend. It will also allow the applicant to more 

easily test for germination of refuge seed (to assure the 5% refuge is still guaranteed). 

Monsanto has submitted additional information and a generic standard operating procedure to 

guarantee the same accuracy and quality assurance from independent seed dealers who are in charge 
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of their own seed mixing process Unfortunately, this information was very general and not specific 

enough for BPPD to ascertain that the target blend percentage will be assured in non-Monsanto 

facilities. 

It was not clear from reading Dow's document what the actual target weight and 

percentage will be should a 5% MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed 

blend be commercialized. This information is needed. 

 3. Seed Blend Monitoring under the Federal Seed Act

The United States Agricultural Marketing Service and State Seed Control Officials are involved 

with ensuring compliance to the Federal Seed Act by seed producers. Testing of seed blend 

products for refuge component percentage has and will be taking place. If either USDA or State 

Seed Control Officials obtain official samples of seed blend products, do color separations on the 

composite samples collected and find the percentage of the refuge component is lower in those 

samples than is represented on the label, action may be initiated under the Federal Seed Act. 

IRM Refuge Compliance

Critical to an assessment of the likely efficacy of an IRM mitigation program is the level of 

compliance with that program. Data received by EPA from the Agricultural Biotechnology 

Stewardship Technical Committee (ABSTC) indicate that compliance with the paradigmatic 

20% block refuge requirement for most B.t. corn crops has been steadily decreasing. This 

decreased compliance increases the risk of resistance development (see, e.g., Complacency on 

the Farm, CSPI 2009, and Impact of Genetically Engineered Crops on Farm Sustainability in the 

United States, NAS 2010). 

Grower survey results (see Figure 1) show that average compliance with refuge distance 

requirements for ECB protected corn expressing single PIPs was significantly higher in 2010 

than in the previous year (margin of error +6.0%); compliance with refuge size remained 

approximately equal compared to 2009. Growers reported to be out of compliance deviated from 

the 20% requirement in one way or another. Further analysis of non-compliance numbers 

revealed that most farmers (87%) planted a refuge that was at least 15%, and that 5% of farmers 

neglected to plant a refuge at all. A regional analysis revealed that growers planting single ECB 

PIP expressing corn in eastern regions of the Corn Belt were less compliant on average (71% for 

refuge size, 83% for refuge requirement) than growers in the western regions (81% for refuge 

size and 90% for distance requirement). Growers in the southern U.S. had significantly lower 

adherence percentages than the Corn Belt again; the 2010 analysis reveals, however, that 

compliance in the south has had a small, yet statistically, significant increase in compliance 

compared to 2009 (from 40% in 2009 to 49% in 2010 for refuge size; from 63% in 2009 to 70% 

in 2010 for refuge distance). It is unclear whether the observed difference is due to the smaller 

sample size in the south, which was reduced by 60% compared to the sample size in the eastern 

and western regions of the US. However, compliance is still below an acceptable level in the 

south; possible explanations for such lower compliance in the south could include confusion with 

different requirements between various PIP products or simply blatant disregard of refuge 

requirements by growers who plant both Bt corn and Bt cotton. ABSTC stated in their 2009 CAP 

report that these regional results provided them with the opportunity to intensify future 

educational efforts in the southern corn growing regions. BPPD notes that if higher noncompliance among southern corn growers reflects a willingness to violate refuge requirements 
MON 89034 x TC1507 x MON 88017 x DAS-59122-7 (SmartStax®) B.t. Corn Seed Blend Page 19 of 39 

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rather than a lack of knowledge, then increased efforts to educate them may not be fruitful. Other 

methods to bring these growers back into compliance may need to be considered. 

Grower awareness with IRM requirements was high (94%), yet the number of growers who 

could recall the correct refuge size (65%) was significantly lower compared to the number of 

growers who recalled the correct refuge distance requirements (82%). These percentages are 

reflective of the compliance numbers from the online survey. 

0

20

40

60

80

100

120

'02 '03 '04 '05 '06 '07 '08 '09 '10

% Compliance

Planting season

Compliance with refuge requirementsfor ECB protected

corn PIPs

refuge size

refuge distance

 Figure 1 Compliance trend from 2002-2010 for growers planting single ECB PIPs 

Overall compliance (per grower) with refuge requirements for single PIPs targeting CRW is 

displayed in Figure 2. Average compliance in 2010 has again decreased compared to 2009 and is 

now at the level of compliance (73% for refuge size, 67% for refuge distance) similar to that 

reported in 2008. The margin of error reported for CRW PIP compliance data is ±13.3%, hence 

the difference measured between 2010 and 2009 compliance is not statistically significant. The 

percentage of growers blatantly disregarding refuge requirements in 2010 was again 9%, as in 

2009. Eighteen percent (18%) of all corn rootworm protected fields had no refuge associated 

with them; this is an increase from the 14% reported in 2009. 

 

Grower awareness with IRM requirements in 2010 was higher than in 2009, yet, the percentage 

of growers who could recall the refuge size and distance requirements was extremely low (33% 

and 22%, respectively). That is a drastic decline from an already low awareness in 2009 of 58% 

and 31% for correct refuge size and refuge distance. These percentages are now at an all time 

low. BPPD believes that this decline in grower knowledge is reason for concern and somewhat 

reflective of the compliance numbers from the online survey. ABSTC’s educational efforts have 

been unsuccessful at increasing grower education with respect to CRW IRM requirements. 
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0

20

40

60

80

100

'05 '06 '07 '08 '09 '10

% Compliance

Planting season

Compliance with refuge requirementsfor CRW

protected corn PIPs

refuge size

refuge distance

 Figure 2 Compliance trend from 2005-2010 for growers planting single CRW PIPs 

Overall compliance (per grower) with refuge requirements for stacked corn PIPs is displayed in 

Figure 3. In 2010, the reported margin of error for adherence with requirements was again 

±4.2%; therefore, BPPD concludes that the latest national average compliance results were 

similar to those reported in prior years. A regional analysis of survey results revealed that 

growers’ compliance in eastern regions of the US significantly declined: adherence to refuge size 

requirements was 74% in 2009 and declined to 69% in 2010; adherence to refuge distance was 

67% in 2009 and declined to 63%. Compliance in the western regions of the Corn Belt remained 

similar or slightly higher to those reported in 2009. Corn growers in the cotton growing regions 

had similar compliance in 2010 as in 2009 – 32% and 37% for adherence to refuge size and 

distance requirements. BPPD notes that the compliance percentages in the south are extremely 

low. 

BPPD notes that the number of growers who were able to correctly recall IRM requirements on 

an unaided basis reached an all time low since 2007. Only 27% of growers were able to correctly 

recall the correct distance requirement for the CRW portion of the PIP in 2010. This represents a 

further decline from the reported 32% in 2009. Only 56% of the growers surveyed recalled that 

refuge size for the CRW PIP was 20%. The increased educational outreach by ABSTC is not 

producing the expected results among corn growers planting stacked PIPs. 
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0

20

40

60

80

100

'06 '07 '08 '09 '10

% Compliance

Planting season

Compliance with refuge requirementsfor stacked corn

PIPs

refuge size

refuge distance

 Figure 3 Compliance trend from 2006-2010 for growers planting stacked corn PIPs 

Table 2 shows the percent of growers who have blatantly disregarded refuge requirements for the 

individual PIP products planted in 2009 and 2010. Unfortunately, this information was not 

provided to the Agency prior to 2009 and no historical comparison can, therefore, be made yet. 

Table 2. Percent growers planting a zero % refuge for stacked Corn PIPs (data from 2009-2010) 

Product Type 20091 20101

Single ECB PIPs 7% 5% 

Single CRW PIPs 9% 9% 

Stacked ECB/CRW 

PIPs 

11% 12% 

1

Results are listed on a per grower (not per field) basis 

B. Product Characterization and Human Health Assessment

Current tolerance exemptions in 40 CFR Part 174 applicable to MON 89034 × TC1507 × MON 

88017 × DAS-59122-7. 

§ 174.502 Bacillus thuringiensisCry1A.105 protein; exemption from the requirement of a 

tolerance. 

(a) Residues of Bacillus thuringiensis Cry1A.105 protein in or on the food and feed 

commodities of corn; corn, field, flour; corn, field, forage; corn, field, grain; corn, field, 

grits; corn, field, meal; corn, field, refined oil; corn, field, stover; corn, sweet, forage; corn, 

sweet, kernel plus cob with husk removed; corn, sweet, stover; corn, pop, grain and corn, 

pop, stover are exempt from the requirement of a tolerance when the Bacillus thuringiensis 
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Cry1A.105 protein is used as a plant-incorporated protectant in these food and feed corn 

commodities. 

§ 174.506 Bacillus thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn; exemption 

from the requirement of a tolerance. 

Residues of Bacillus thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn are exempted from 

the requirement of a tolerance when used as plant-incorporated protectants in the food and feed 

commodities of corn; corn, field; corn, sweet; and corn, pop. 

§ 174.507 Nucleic acids that are part of a plant-incorporated protectant; exemption from 

the requirement of a tolerance. 

Residues of nucleic acids that are part of a plant-incorporated protectant are exempt from the 

requirement of a tolerance. 

§ 174.518 Bacillus thuringiensis Cry3Bb1 protein in corn; exemption from the 

requirement of a tolerance. 

Residues of Bacillus thuringiensis Cry3Bb1 protein in corn are exempt from the requirement of a 

tolerance when used as plant-incorporated protectants in the food and feed commodities of corn; 

corn, field; corn, sweet; and corn, pop. 

§ 174.519 Bacillus thuringiensis Cry2Ab2 protein in corn and cotton; exemption from the 

requirement of a tolerance. 

Residues of Bacillus thuringiensis Cry2Ab2 protein in or on corn or cotton are exempt from the 

requirement of a tolerance when used as a plant–incorporated protectant in the food and feed 

commodities of corn; corn, field; corn, sweet; corn, pop; and cotton seed, cotton oil, cotton meal, 

cotton hay, cotton hulls, cotton forage, and cotton gin byproducts. 

§ 174.520 Bacillus thuringiensis Cry1F protein in corn; exemption from the requirement 

of a tolerance. 

Residues of Bacillus thuringiensis Cry1F protein in corn are exempt from the requirement of a 

tolerance when used as plant-incorporated protectants in the food and feed commodities of corn; 

corn, field; corn, sweet; and corn, pop. 

§ 174.523 CP4 Enolpyruvylshikimate-3-phosphate (CP4 EPSPS) synthase in all plants; 

exemption from the requirement of a tolerance. 

Residues of the CP4 Enolpyruvylshikimate-3-phosphate (CP4 EPSPS) synthase enzyme in all 

plants are exempt from the requirement of a tolerance when used as plant-incorporated protectant 

inert ingredients in all food commodities.

§ 174.522 Phosphinothricin Acetyltransferase (PAT); exemption from the requirement of 

a tolerance. 

Residues of the Phosphinothricin Acetyltransferase (PAT) enzyme are exempt from the 
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requirement of a tolerance when used as plant-incorporated protectant inert ingredients in all 

food commodities. 

Southern Blot Analysis

Southern blot analysis confirmed in the combined trait corn product MON 89034 × TC1507 × MON 

88017 × DAS-59122-7 the presence of sequences identical to sequences derived from MON 89034 

and MON 88017.Hybridization patterns for the combined trait product were identical to those of the 

parental lines with cry1F, cry34Ab1, cry35Ab1, and the pat gene probes indicating that the TC1507 

and DAS-59122-7 insertions were unaffected by combining with MON 89034 and MON 88017 

through conventional breeding. 

Expression Levels

MON 89034 x TC1507 x MON 88017 x DAS-59122-7 is a combined trait corn that produces 

lepidopteran-active and coleopteran-active Bacillus thuringiensis (Bt) proteins, as well as the 5-

enolpyruvylshikimate-3-phosphate synthase protein from Agrobacterium sp. strain CP4 (CP4 

EPSPS) to confer tolerance to glyphosate herbicides and PAT to confer tolerance to glufosinate 

herbicides. The levels of the lepidopteran-active Cry1A.105, Cry2Ab2, Cry3Bb1 proteins and the 

CP4 EPSPS protein were determined in tissues from MON 89034 x TC1507 x MON 88017 x DAS59122-7 plants grown at five US field sites in 2006. The test also included a conventional corn as a 

negative control and MON 89034 and MON 88017 corns as positive controls. Leaf, root, and whole 

plant samples were collected over the growing season, as well as pollen and grain samples at the 

appropriate times. The samples were extracted and analyzed using enzyme-linked immunosorbent 

assays. The levels of the Cry1A.105, Cry2Ab2, Cry3Bb1, and CP4 EPSPS proteins in MON 89034 x 

TC1507 x MON 88017 x DAS-59122-7 corn were comparable to those in the appropriate MON 

88017 or MON 89034 positive control. 

The levels of the coleopteran-active Bacillus thuringiensis (Bt) proteins Cry34Ab1, Cry35Ab1, and 

Cry1F, and the PAT protein were determined in tissues from MON 89034 x TC1507 x MON 88017 

x DAS-59122-7 plants grown at five US field sites in 2006. The test also included a conventional 

corn as a negative control and TC1507 and DAS-59122-7 parental event corn as positive controls. 

Leaf, root, and whole plant samples were collected over the growing season, as well as pollen and 

grain samples at the appropriate times. The samples were extracted and analyzed using enzymelinked immunosorbent assays (ELISA). The results indicate that the levels of Cry34Ab1, Cry35Ab1, 

and Cry1F in MON 89034 x TC1507 x MON 88017 x DAS-59122-7 were comparable to the levels 

produced in the appropriate TC1507 or DAS-59122-7 control corn. The level of PAT in MON 89034 

x TC1507 x MON 88017 x DAS-59122-7 was higher in the combined trait products compared to 

TC1507 and DAS-59122-7, likely due to the presence of multiple copies of the pat gene in the stacks 

(one from each of the DAS parent lines). 

C. Environmental Assessment

At present, the Agency has not identified any significant adverse effects of the Cry1A.105, 

Cry2Ab2, Cry1F, Cry3Bb1, or Cry34Ab1/35Ab1 proteins on the abundance of non-target 

organisms in any field population, whether expressed individually or as MON 89034 x TC1507 x 

MON 88017 x DAS-59122-7 combined PIP corn product. The potential for synergistic effects 

has been evaluated and the data that were reviewed for the individual parental events can be 

bridged to support the Sec. 3 registration of MON 89034 x TC1507 x MON 88017 x DAS-
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59122-7 combined PIP corn product. 

It is unlikely that direct or indirect harmful effects to non-target organisms, including federallylisted threatened or endangered species, would result from the insecticidal proteins Cry1A.105, 

Cry2Ab2, Cry1F, Cry3Bb1, or Cry34/35Ab as a result of the proposed Sec. 3 registration. The 

Agency anticipates that for full commercial cultivation, no hazard will result to the environment. 

Event MON 89034 produces the Cry1A.105 and Cry2Ab2 Bt proteins, and Event TC1507 

produces Cry1F. These proteins are intended to control or suppress several lepidopteran pests of 

corn, including European corn borer (ECB, Ostrinia nubilalis), corn earworm (CEW, 

Helicoverpa zea), fall army worm (FAW, Spodoptera frugiperda), and black cutworm (BCW, 

Agrotis ipsilon). MON 88017 produces the Cry3Bb1 protein, and Event DAS-59122-7 produces 

the Cry34Ab1 and Cry35Ab1 proteins. These two events provide additional control for 

coleopteran pests, particularly corn rootworm pests (Diabrotica spp.). 

It has been determined that each individual event has protein expression levels that are 

comparable to the MON 89034 x TC1507 x MON 88017 x DAS-59122-7 corn hybrid (Kough, 

2009). Therefore, the margins of exposure that were previously determined for the insecticidal 

proteins in the individual events are applicable for the risk assessment of these proteins in the 

stacked hybrid. Additionally, no synergistic or antagonistic effects were observed in several 

combinations of the individual events in MON 89034 x TC1507 x MON 88017 x DAS-59122-7, 

as well as the MON 89034 x TC1507 x MON 88017 x DAS-59122-7 hybrid itself. As a result, 

the Agency concludes that there is no indication of synergistic effects or increased levels of 

protein expressed in the combined PIP product, so the environmental risk assessment for the 

single PIP lines are applicable to the assessment of MON 89034 x TC1507 x MON 88017 x 

DAS-59122-7. 

As a result, the environmental risk assessment of the individual events, as well as an additional 

study submitted on the toxicity of MON 89034 x TC1507 x MON 88017 x DAS-59122-7 to a 

non-target insect, the Agency concluded that there will be no unreasonable adverse effects to the 

environment, including endangered species, by MON 89034 x TC1507 x MON 88017 x DAS59122-7 combined trait corn. 

D. Benefits

We expect MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blend products to have 

the following benefits: (1) Reduced pesticide use in the refuge. Currently, the block refuge may 

be sprayed with pesticide to mitigate pest damage. The blended in-field refuge will not be 

sprayable. (2) Significantly less complicated refuge deployment for the corn rootworm and 

lepidopteran active ingredients. Currently, to be fully compliant with the refuge requirements, 

growers must accurately calculate percentage of the field, accurately determine the proper 

distance for the refuge field, and properly plant the required acreage in the correct location. 

Moreover, there are temporal concerns, as the refuge field must be planted at, essentially, the 

same time as the yield field so that emergence of refuge rootworms is contemporaneous with 

emergence of field rootworms. Anecdotal reports from growers make clear that meeting each of 

these requirements can be challenging in the actual on-farm environment. A product with the 

refuge blended with the field seed will ease deployment of the refuges. (3) Grower compliance 

with IRM requirements for the corn rootworm and lepidopteran active ingredients. A seed blend 

product incorporating an effective refuge in the seed bag would lead to 100% grower compliance 
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for planting a refuge. This is a significant benefit, although perhaps not as great as the raw data 

on refuge compliance might suggest. 

In addition, indirect benefits of introducing MON 89034 x TC1507 x MON 88017 x DAS59122-7 seed blends may include reduced energy consumption for manufacture, transport, and 

application of chemical insecticides; reduced waste streams arising from pesticide manufacture; 

reduced disposal of pesticide waste containers; and reduced residues from pesticide applications. 

 

III. REGULATORY RATIONALE 

Section 3(c)(7)(A) of FIFRA provides for the registration or amendment of a pesticide when the 

pesticide and proposed use “...are identical or substantially similar to any currently registered 

pesticide and use thereof, or differ only in ways that would not significantly increase the risk of 

unreasonable adverse effects on the environment, and (ii) approving the registration or 

amendment in the manner proposed by the applicant would not significantly increase the risk of 

any unreasonable adverse effect on the environment.” Unreasonable adverse effects on the 

environment are defined under Section 2(bb) of FIFRA as “... any unreasonable risk to man or 

the environment, taking into account the economic, social, and environmental costs and benefits 

of the use of any pesticide...” Thus, pursuant to Section 3(c)(7)(A), EPA may conditionally 

register a pesticide if (1) the pesticide and its proposed use are identical or substantially similar 

to a currently registered pesticide; or (2) the pesticide and its proposed use differ only in ways 

that would not significantly increase the risk of unreasonable adverse effects; and (3) approving 

the registration would not significantly increase the risk of any unreasonable adverse effect. 

We find that the MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blends meet 

criteria (2) and (3) of Section 3(c)(7)(A) for a time-limited registration to expire October 31, 

2011. MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blends consist of a currently 

registered products, 95% MON 89034 x TC1507 x MON 88017 x DAS-59122-7 (MON 89034 x 

TC1507 x MON 88017 x DAS-59122-7 ) and 5% non-B.t. corn. Thus, both products are 

substantially similar to already registered PIPs in composition and use site (field corn). These 

products do not meet criteria (1), however, because the proposed use of the MON 89034 x 

TC1507 x MON 88017 x DAS-59122-7 seed blends achieves the lepidopteran insect resistance 

management refuge via a seed mix rather than a block refuge is not substantially similar to any 

currently registered pesticide. 

We determine, however, that the MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed 

blends meet criteria (2) as, when used in accordance with the terms and conditions of a timelimited registration set to expire October 31, 2011, and would not significantly increase the risk 

of unreasonable adverse effects on the environment. Since the MON 89034 x TC1507 x MON 

88017 x DAS-59122-7 seed blends are substantially similar to already registered PIPs in 

composition and use site, EPA’s consideration of whether these new products would 

significantly increase the risk of any unreasonable adverse effect on the environment is limited to 

the change in lepiidopteran insect resistance management refuge deployment, i.e., a seed blend 

in the bag versus a block refuge. The unreasonable adverse effect of concern is the development 

of resistance to Cry1F, Cry2Ab2, and Cry1A.105 in corn. Thus, we consider: (1) how does the 

registration of the MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blends contribute 

to the development of corn rootworm resistance to Cry1F, Cry2Ab2, and Cry1A.105 in corn; (2) 

should this resistance develop, what risk does it pose to man or the environment; and (3) taking 
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into account the economic, social, and environmental costs and benefits, does this risk constitute 

an unreasonable adverse effect? 

The Risk of the MON 89034 x TC1507 x MON 88017 x DAS-59122-7 Seed Blend

Registrations Causing Lepidopteran Resistance to Cry1F, Cry2Ab2, and Cry1A.105

Based on a review of the Science Advisory Panel (SAP) report (SAP 2011) and revised modeling 

submitted by Monsanto/Dow, BPPD concludes that a 5% seed blend for MON 89034 x TC1507 

x MON 88017 x DAS-59122-7 corn will likely be less durable (perhaps significantly so) than a 

comparable (5%) block refuge for the product, as is currently required for the non –seed blend 

MON 89034 x TC1507 x MON 88017 x DAS-59122-7 products under EPA registration 

numbers 524-581 and 69467-7. BPPD notes, however, that a MON 89034 x TC1507 x MON 

88017 x DAS-59122-7 5% seed blend should be more durable than a 20% block refuge for a 

single toxin Bt corn product (of which many are currently registered) or a comparable (5%) seed 

blend for a two toxin pyramid. 

Should Resistance Develop, What Risk Does it Pose to Man or the Environment, and What 

Economic and Social Costs?

Should Cry1F, Cry2Ab2, or Cry1A.105 resistance develop, there may be an increase in 

conventional chemical insecticide use for U.S. corn production. Although there are other 

lepidopteran controlling PIPs in the marketplace and under development, Cry1F, Cry2Ab2, or 

Cry1A.105 resistance would not only impact MON 89034 x TC1507 x MON 88017 x DAS59122-7 seed blends and non- seed blend products, but also HERCULEX®, and MON89034 . 

Increased use of conventional insecticides would increase impacts on the environment and man. 

There would also be indirect impacts in increased consumption for manufacture, transport, and 

application of chemical insecticides; increased waste streams arising from pesticide manufacture; 

and increased disposal of pesticide waste containers and residues from pesticide applications. 

What are the Economic, Social, and Environmental Benefits of MON 89034 x TC1507 x 

MON 88017 x DAS-59122-7 Seed Blend Registrations?

MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blends have been determined by 

EPA to be efficacious in their control of 

European corn borer, southwester corn borer, corn earworm (and corn rootworm). 

MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blends should increase grower 

compliance with lepidopteran refuge requirements by providing an effective way of simplifying 

the refuge deployment process for growers as the lepidopteran refuge is deployed as a seed 

blend rather than a separate block in the field. 

MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blends should also reduce the 

insecticide use in the lepidopteran refuge. Indirect benefits of decreased insecticide use include 

reduced energy consumption for manufacture, transport, and application of chemical 

insecticides; reduced waste streams arising from pesticide manufacture; reduced disposal of 

pesticide waste containers and residues from pesticide applications. 

MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blends should benefit growers by 

simplifying the planting process. 
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Registration Decision 

We conclude that the MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blends meet 

the criteria for registration under FIFRA Section 3(c)(7)(A). Our assessment supports the 

determination that these products are not likely to contribute towards the development of 

resistance to Cry1F, Cry2Ab2, or Cry1A.105 during period of the time-limited registration in 

effect for the 2011 growing season. Our assessment of the likely impacts concerning ease of use, 

increased grower compliance, efficacy, and reduced insecticide use coupled with our 

determination that the MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blends are 

not likely to increase the risk of resistance to Cry1F, Cry2Ab2, or Cry1A.105 developing during 

the 2011growing season support the conclusion that the criteria under FIFRA Section 3(c)(7)(A) 

are met such that registration of the MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed 

blends will not pose a risk of unreasonable adverse effects on the environment during this period. 

On October 1, 2009, EPA announced a new policy to provide a more meaningful opportunity for 

the public to participate on major registration decisions before they occur. According to this new 

policy, EPA intends to provide a public comment period prior to making a registration decision 

for, at minimum, the following types of applications: new active ingredients; first food use; first 

outdoor use; first residential use; and other actions for which the Agency anticipates that there 

will be significant public interest. 

Notwithstanding that the current actions on the MON 89034 x TC1507 x MON 88017 x DAS59122-7 seed blends qualify as "actions for which the Agency anticipates that there will be 

significant public interest," EPA believes that it is in the best interests of the public and the 

environment to issue the registrations for the MON 89034 x TC1507 x MON 88017 x DAS59122-7 seed blends without delay. The PRIA (Pesticide Registration Improvement Act) 

deadline date of April 12, 2011, is sufficiently late in the growing season that a 30-day delay 

would lessen the likelihood that significant acreage of these products could be planted in 2011. 

Given the potential benefits attendant to the blended refuge concept for both lepidopteran and 

corn rootworm pests, EPA concludes that it is in the best interests of the public and the 

environment to issue the registrations for the MON 89034 x TC1507 x MON 88017 x DAS59122-7 seed blends without delay for 2011 growing season. The registration is only effective 

for the current growing season. Therefore, consistent with the Agency’s policy for making 

certain registration actions more transparent, EPA is issuing these time-limited registrations with 

an initial period to expire October 31, 2011, and, concurrent with their issuance, providing a 30-

day public comment period on the time-limited registrations. EPA is registering this product as a 

time-limited registration, with the understanding that public comments could bring to light new 

information or concerns that could inform EPA’s initial decision. Any subsequent action taken 

on these registrations will be informed by any information received during the public comment 

period. At present, the Agency anticipates renewing the expiration date to October 31, 2013. 

IV. TERMS AND CONDITIONS OF THE REGISTRATION(S) 

 

1) The subject registration will automatically expire at midnight October 31, 2011. 

2) The subject registration will be limited to MON 89034 x TC1507 x MON 88017 x DAS59122-7 seed blend in field corn. 

3) Submit or cite all data required to support MON 89034 x TC1507 x MON 88017 x DAS-
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59122-7 plant-incorporated protectant products within the timeframes required by the terms and 

conditions of EPA Registration Numbers 68467-7 (Dow AgroSciences) and 524-581 

(Monsanto). 

4) Provided the registration expiration date is extended, submit an interim report on the 

following data within one year and a final report within two years. 

 Revised modeling incorporating the structural elements recommended by the SAP (i.e., 

explicit larval movement, switch from a frequency-based model to one including densitydependent larval mortality, epistatic mechanisms for resistance in target pests) with 

separate analyses for SWCB and ECB. Non-uniform oviposition should be modeled for 

both ECB and SWCB, especially (but not only) for the second generation of adults which 

will more likely lay eggs on Bt rather than on damaged (or crowded out) non-Bt refuge 

plants in seed blends. 

 Biological research on adult movement (related to mating and movement from refuges), 

larval movement, larval feeding (i.e., selective feeding within corn ears or on pollen), 

survival of heterozygote genotypes on MON 89034 x TC1507 x MON 88017 x DAS59122-7 (markers may need to be determined for heterozygotes), and the potential for 

epistatic mechanisms of resistance (particularly with older instars). 

5) Do the following Insect Resistance Management Program for MON 89034 x TC1507 x MON 

88017 x DAS-59122-7 seed blend corn. 

a) Refuge Requirements for MON 89034 x TC1507 x MON 88017 x DAS-59122-7 

The following information must be included on the product bag or bag-tag as sold per respective 

region: 

Bag or Bag-Tag for the Corn-Growing Region

There are no requirements for a separate structured refuge for MON 89034 x TC1507 x MON 88017 

x DAS-59122-7 seed blend corn when planted in the U.S. corn-growing region. The refuge seed of 

MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blend corn is contained in the bag 

resulting in a refuge configuration that is interspersed within the field. SEE THE IRM/GROWER 

GUIDE FOR DETAILED IRM REQUIREMENTS, including the areas making up the corn-growing 

region. 

Bag or Bag-Tag for the Cotton-Growing Region 

Growers in the cotton-growing region of the U.S. who plant MON 89034 x TC1507 x MON 88017 x 

DAS-59122-7 seed blend corn are required to plant an additional 20% structured refuge (i.e. 20 acres 

of non-B.t. corn for every 80 acres of MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed 

blend corn planted). The 20% refuge must be planted with corn hybrids that do not contain B.t. 

technologies for the control of corn rootworms or corn borers. The refuge and the MON 89034 x 

TC1507 x MON 88017 x DAS-59122-7 seed blend corn should be sown on the same day, or with 

the shortest window possible between planting dates to ensure that corn root development is similar 

among varieties. The structured refuge may be planted as an in-field or adjacent (e.g., across the 

road) refuge, or as a separate block that is within 1⁄2 mile of the MON 89034 x TC1507 x MON 

88017 x DAS-59122-7 seed blend corn field. SEE THE IRM/GROWER GUIDE FOR DETAILED 
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IRM REQUIREMENTS, including the areas making up the cotton-growing region. 

The cotton-growing region requiring the additional 20% refuge consists of the following states: 

Alabama, Arkansas, Georgia, Florida, Louisiana, North Carolina, Mississippi, South Carolina, 

Oklahoma (only the counties of Beckham, Caddo, Comanche, Custer, Greer, Harmon, Jackson, Kay, 

Kiowa, Tillman, and Washita), Tennessee (only the counties of Carroll, Chester, Crockett, Dyer, 

Fayette, Franklin, Gibson, Hardeman, Hardin, Haywood, Lake, Lauderdale, Lincoln, Madison, 

Obion, Rutherford, Shelby, and Tipton), Texas (except the counties of Carson, Dallam, Hansford, 

Hartley, Hutchinson, Lipscomb, Moore, Ochiltree, Roberts, and Sherman), Virginia (only the 

counties of Dinwiddie, Franklin City, Greensville, Isle of Wight, Northampton, Southampton, 

Suffolk City, Surrey, and Sussex) and Missouri (only the counties of Dunklin, New Madrid, 

Pemiscot, Scott, and Stoddard). 

The following information regarding refuge placement for commercial production must be included 

in the IRM/Grower Guide: 

This product includes refuge that is interspersed within the field by planting a licensed seed-mixture 

containing MON 89034 × TC1507 × MON 88017 × DAS-59122-7 and a minimum of 5% non-PIP 

seed. The seed mix refuge option for MON 89034 × TC1507 × MON 88017 × DAS-59122-7 seed 

blend corn satisfies the refuge requirements in all regions other than in cotton growing regions where 

corn earworm is a significant pest as defined below. 

The seed producer must ensure a minimum of 5% non-PIP refuge seed is included with the 

MON 89034 × TC1507 × MON 88017 × DAS-59122-7 in each lot of seed corn. 

The interspersed refuge can only be used by planting seed corn specifically generated by qualified 

seed producers/conditioners licensed by the registrant. The refuge seed in the seed mixture may not 

be treated with seed-applied insecticides for corn rootworm (CRW) control unless the MON 89034 × 

TC1507 × MON 88017 × DAS-59122-7 seed in the seed mixture receives the same treatment. 

Insecticidal treatments labeled for adult CRW control are discouraged during the time of adult CRW 

emergence. 

Additional refuge requirements in cotton-growing regions where corn earworm is a significant 

pest

In cotton-growing regions where corn earworm is a significant pest, as defined below, MON 89034 

× TC1507 × MON 88017 × DAS-59122-7 seed blend corn requires the planting of an additional 

20% structured refuge (i.e. 20 acres of non-Bt corn for every 80 acres of MON 89034 × TC1507 × 

MON 88017 × DAS-59122-7 seed blend corn planted). 

The 20% refuge must be planted with corn hybrids that do not contain Bt technologies for the control 

of corn rootworms or corn borers. The refuge and the MON 89034 × TC1507 × MON 88017 × 

DAS-59122-7 seed blend corn should be sown on the same day, or with the shortest window 

possible between planting dates to ensure that corn root development is similar among varieties. The 

structured refuge may be planted as an in-field or adjacent (e.g., across the road) refuge, or as a 

separate block that is within 1⁄2 mile of the MON 89034 × TC1507 × MON 88017 × DAS-59122-7 

seed blend corn field. In-field refuge options include blocks, perimeter strips (i.e., strips around the 

field), or in-field strips. If perimeter or in-field strips are implemented, the strips must be at least 4 

consecutive rows wide. The refuge can be protected from lepidopteran damage by use of non-Bt 
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insecticides if the population of one or more target lepidopteran pests of MON 89034 × TC1507 × 

MON 88017 × DAS-59122-7 seed blend corn in the refuge exceeds economic thresholds. In 

addition, the refuge can be protected from CRW damage by an appropriate seed treatment or soil 

insecticide; however, insecticides labeled for adult CRW control must be avoided in the refuge 

during the period of CRW adult emergence. Economic thresholds will be determined using methods 

recommended by local or regional professionals (e.g., Extension Service agents, crop consultants). 

The cotton-growing region requiring the additional 20% refuge consists of the following states: 

Alabama, Arkansas, Georgia, Florida, Louisiana, North Carolina, Mississippi, South Carolina, 

Oklahoma (only the counties of Beckham, Caddo, Comanche, Custer, Greer, Harmon, Jackson, Kay, 

Kiowa, Tillman, and Washita), Tennessee (only the counties of Carroll, Chester, Crockett, Dyer, 

Fayette, Franklin, Gibson, Hardeman, Hardin, Haywood, Lake, Lauderdale, Lincoln, Madison, 

Obion, Rutherford, Shelby, and Tipton), Texas (except the counties of Carson, Dallam, Hansford, 

Hartley, Hutchinson, Lipscomb, Moore, Ochiltree, Roberts, and Sherman), Virginia (only the 

counties of Dinwiddie, Franklin City, Greensville, Isle of Wight, Northampton, Southampton, 

Suffolk City, Surrey, and Sussex) and Missouri (only the counties of Dunklin, New Madrid, 

Pemiscot, Scott, and Stoddard). 

b) Grower Agreement for MON 89034 x TC1507 x MON 88017 x DAS-59122-7 Seed Blend 

Corn

1) Persons purchasing MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blend corn 

must sign a grower agreement. The term “grower agreement” refers to any grower purchase 

contract, license agreement, or similar legal document. 

2) The grower agreement and/or specific stewardship documents referenced in the grower 

agreement must clearly set forth the terms of the current IRM program. By signing the grower 

agreement, a grower must be contractually bound to comply with the requirements of the IRM 

program. 

3) Monsanto and Dow must implement a system (equivalent to what is already approved for 

previously registered Monsanto and Dow Bt corn products), which is reasonably likely to assure 

that persons purchasing MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blend corn 

will affirm annually that they are contractually bound to comply with the requirements of the 

IRM program. A description of the system must be submitted to EPA within 90 days from the 

date of registration. 

4) Monsanto and Dow must use a grower agreement and must submit to EPA, within 90 days 

from the date of registration, a copy of that agreement and any specific stewardship documents 

referenced in the grower agreement. If Monsanto and Dow wish to change any part of the 

grower agreement or any specific stewardship documents referenced in the grower agreement 

that would affect either the content of the IRM program or the legal enforceability of the 

provisions of the agreement relating to the IRM program, 30 days prior to implementing a 

proposed change, Monsanto and Dow must submit to EPA the text of such changes to ensure that 

it is consistent with the terms and conditions of this registration. 

5) Monsanto and Dow must implement a system (equivalent to what is already approved for 

previously registered Monsanto and Dow Bt corn products), which is reasonably likely to assure 

that persons purchasing MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blend corn 
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sign grower agreement(s). A description of the system must be submitted to EPA within 90 days 

from the date of registration. 

6) Monsanto and Dow shall maintain records of all MON 89034 x TC1507x MON 88017 x 

DAS-59122-7 seed blend corn grower agreements for a period of three years from December 

31st of the year in which the agreement was signed. 

7) Beginning on January 31, 2012 and annually thereafter, Monsanto and Dow shall provide 

EPA with a report on the number of units of MON 89034 x TC1507 x MON 88017 x DAS59122-7 seed blend corn seed shipped and not returned, and the number of such units that were 

sold to persons who have signed grower agreements. The report shall cover the time frame of a 

twelve-month period. Note: The first report shall contain the specified information from the time 

frame starting with the date of registration and extending through the 2010 growing season. 

8) Monsanto and Dow must allow a review of the grower agreements and grower agreement 

records by EPA or by a State pesticide regulatory agency if the State agency can demonstrate 

that confidential business information, including names, personal information, and grower 

license number, will be protected. 

c) IRM Education and IRM Compliance Monitoring Program for MON 89034 x TC1507 x 

MON 88017 x DAS-59122-7 Seed Blend Corn

1) Monsanto and Dow must design and implement a comprehensive, ongoing IRM education 

program designed to convey to MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed 

blend corn users the importance of complying with the IRM program. The education program 

shall involve the use of multiple media, e.g. face-to-face meetings, mailing written materials, 

EPA-reviewed language on IRM requirements on the bag or bag tag, and electronic 

communications such as by internet, radio, or television commercials. Copies of the materials 

will be provided to EPA for their records. The program shall involve at least one written 

communication annually to each MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed 

blend corn user separate from the grower technical guide. The communication shall inform the 

user of the current IRM requirements. Monsanto and Dow shall coordinate its education 

program with the educational efforts of other registrants and other organizations, such as the 

National Corn Growers Association and state extension programs. 

2) Annually, Monsanto/Dow shall revise, and expand as necessary, its education program to 

take into account the information collected through the compliance survey and from other 

sources. The changes shall address aspects of grower compliance that are not sufficiently high. 

3) Beginning January 31, 2012, Monsanto and Dow must provide a report to EPA summarizing 

the activities it carried out under its education program for the prior year. Annually thereafter, 

Monsanto and Dow must provide EPA any substantive changes to its grower education activities 

as part of the overall IRM compliance assurance program report. Monsanto/Dow must either 

submit a separate report or contribute to the report from the industry working group, Agricultural 

Biotechnology Stewardship Technical Committee (ABSTC). 

4) Given that MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blend will likely 

have different refuge strategies for lepidoptera and CRW than other registered Bt corn products, 

Monsanto/Dow must submit a revised compliance assurance program (CAP) within 90 days of 
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the date of registration. This revised CAP must be found acceptable by BPPD by April 1, 2012. 

This strategy should be specific for MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed 

blend corn and the new refuge requirements. Availability of non-Bt corn refuge seeds in 

desirable varieties must be addressed. Compliance is an area of ongoing concern -- recent data 

have shown that refuge compliance for Bt corn has fallen in recent years. 

d) Insect Resistance Monitoring and Remedial Action Plans for MON 89034 x TC1507 x 

MON 88017 x DAS-59122-7 Corn 

Existing programs for resistance monitoring and remedial action for MON 89034 x TC1507 x 

MON 88017 x DAS-59122-7 are applicable and required for MON 89034 x TC1507 x MON 

88017 x DAS-59122-7 seed blend corn. Monsanto/Dow must submit a revised definition of 

unexpected damage in MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blend corn 

for resistance monitoring must also submit a remedial action plan within 90 days of the date of 

registration that must be found acceptable to BPPD by April 1, 2012. 

A report on results of resistance monitoring and investigations of damage reports must be 

submitted to the Agency annually by August 31st each year, beginning in 2012, for the duration 

of the conditional registration. 

e) Annual Reporting Requirements for MON 89034 x TC1507 x MON 88017 x DAS-59122-

7 Seed Blend Corn

1) Annual Sales: reported and summed by state (county level data available by request) 

January 31st each year, beginning in 2012; 

2) Grower Agreements: number of units of MON 89034 x TC1507 x MON 88017 x DAS59122-7 seed blend corn seed shipped or sold and not returned, and the number of such units that 

were soldto persons who have signed grower agreements, January 31st each year, beginning in 

2011; 

3) Grower Education: substantive changes to education program completed previous 

 year, January 31st each year, beginning in 2012; 

4) Compliance Assurance Program: compliance assurance program activities and results for the 

prior year and plans for the compliance assurance program for the current year, 

 January 31st each year, beginning in 2012; 

5) Compliance Survey Results: results of annual surveys for the prior year and survey 

plans for the current year; full report January 31st each year, beginning in 2012; 

6) Insect Resistance Monitoring Results: results of monitoring and investigations of 

damage reports, August 31st each year, beginning in 2012. 

f) Refuge Assurance Program for MON 89034 x TC1507 x MON 88017 x DAS-59122-7 

Seed Blend Corn

Monsanto, Monsanto’s seed company licensees, and Dow must continue to implement a blended 

seed refuge assurance program designed to ensure MON 89034 x TC1507 x MON 88017 x 
MON 89034 x TC1507 x MON 88017 x DAS-59122-7 (SmartStax®) B.t. Corn Seed Blend Page 33 of 39 

Biopesticides Registration Action Document

DAS-59122-7 seed blend corn products are formulated with the appropriate rate of refuge seeds. 

 

The program must include the following four elements: 

1. Trait purity check on seed lots prior to blending (Monsanto and Monsanto Licensees) 

Trait purity check on component seed lots prior to release of the blend for sale (Dow) 

2. Standard Operating Procedures for the blending process; 

3. Calibration of blending equipment; and 

4. Records and data retention records for seed blend products. 

 Calibration records – Monsanto, Monsanto’s Licensees, and Dow will retain 

documentation for three (3) years on the equipment calibration including the 

procedure, when it was conducted and the results. 

 Blend proportion records (weight and kernel based) – Monsanto, Monsanto 

Licensees, and Dow will retain documentation for three (3) years on the kernel 

per pound data of the components, the calculations to determine the proportions 

based on weight and the actual weights that are blended together to make up an 

MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blend corn product 

by seed lot. 

All records must be maintained at the Monsanto, Monsanto Licensees, and Dow blending facility 

and must be available for the EPA review upon request. 

Within one year of the date of registration Monsanto will collect documentation from 

qualification test runs that validate blend percentages from their licensees/conditioners that 

produce MON 89034 x TC1507 x MON 88017 x DAS-59122-7 seed blend corn and submit this 

data to the Agency. Any licensee/conditioner that is unable to verify their blend accuracy will 

provide evidence demonstrating application and participation in the USDA USA Accredited 

Seed Conditioning Program (ASCP) as outlined in ARC 1005D Appendix, 

http://www.ams.usda.gov/AMSv1.0/ams.fetchTemplateData.do?template=TemplateN&navID=

AccreditedSeedPrograms&rightNav1=AccreditedSeedPrograms&topNav=&leftNav=&page=AS

LProgram&resultType=&acct=audrevcom. 

Should Monsanto, Monsanto’s Licencees, or Dow be notified by the USDA/AMS or State Seed 

Control Officials that your seed blend products have been found to have a lower percentage of 

the refuge component than is represented on the label, they must notify EPA within 30 days. This 

would constitute information reportable under FIFRA section 6(a)(2). 

Dow must document what the actual target weight and percentage will be for a 5% MON 89034 

x TC1507 x MON 88017 x DAS-59122-7 seed blend within 1 year. 

6) Monsanto must submit revised product labeling that indicates one seed tag for use in both 

cotton and non-cotton growing areas within six months. 

7) Monsanto must report on how many of their licensees (by number and percentage) color seed 

January 31st each year, beginning in 2012.
MON 89034 x TC1507 x MON 88017 x DAS-59122-7 (SmartStax®) B.t. Corn Seed Blend Page 34 of 39 

Biopesticides Registration Action Document

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