CONCLUSIONS AND RECOMMENDATIONS 

BPPD concurs with ABSTC that the majority of growers who planted single trait and stacked 

ECB/CRW PIP products were compliant with the refuge requirements in 2009 when national 

average results from the on-line survey were considered. Although the degree of non-compliance in 

2009 was in some instances lower than in 2008, these differences were not statistically significant. 

When on-line compliance results were evaluated on a regional basis, however, it was evident that 

southern corn growers were up to 2.4 times less compliant than their northern counterparts. BPPD 

is concerned with these findings and recommends that ABSTC propose alternative approaches to 

increase refuge compliance in the southern corn growing regions of the U.S. 

ABSTC concluded that compliance with CRW protected PIPs has seen some improvements. It is 

correct that compliance with refuge size and distance was somewhat higher in 2009 compared to 

2008. However, the margin of error for adherence with requirements was ±12%, and the increase in 

compliance seen in 2009 was below that reported margin of error. Hence, the difference in 

adherence to refuge requirements for single CRW corn PIP was not statistically significant between 

2008 and2009. 

In contrast to the online survey program, ABSTC states that “the on farm assessment program is 

not a statistical tool for measuring the level of adherence to the IRM requirements”, and that rather, 

“this program helps identify obstacles that hinder grower implementation of IRM requirements”. 

BPPD notes that a comparison between year-to-year on-farm survey results then should be made 

with caution because, among other things, the growers were not randomly selected from 

companies’ customer lists. Nonetheless, it is difficult to ignore that that on-farm compliance for 

CRW protected traits was 85.8% in 2008 and 69% in 2009, and that the percentage of significant 

violations was 9% in 2008 and 26.4% in 2009. BPPD is aware that companies do not share their 

clientele list with each other and that names and locations of non-compliant growers are 

confidential and anonymous for the Agency. Yet, BPPD proposes that ABSTC compile and 

maintain, through a neutral third party, maps showing the distribution of on-farm non-compliance 

pooled across registrants so that it is clear to the BPPD IRM team where these non-compliant 

regions are in the Corn Belt. It may then be possible for ABSTC to increase compliance in these 

regions with increased educational outreach by the registrants or other appropriate new measures. 

It is recommended that ABSTC continue to work with BPPD to develop future steps that could be 

implemented to address low compliance for southern corn growers (on-line survey) and adherence 

to refuge requirements for, especially, single CRW PIPs as seen in last year’s on-farm survey. 

It is recommended that ABSTC address the newly approved refuge requirements in the 2010 CAP: 

5% and 20% structured refuge in the Corn Belt and cotton growing regions, respectively, for 

pyramided lepidopteran traits. Future survey results for 5% and 20% structured refuge in the Corn 

Belt should be separately collected, analyzed, and provided to BPPD (as for 20% and 50% 

structured refuge requirements in the cotton growing regions). 

- 2 - 
I. BACKGROUND

As a condition of registration for the corn borer-protected Bt (Bacillus thuringiensis) corn 

products (EPA Reg. Nos. 524-489, 68467-2, 67979-1 and 29964-3), corn rootworm-protected 

Bt corn products (EPA Reg. Nos. 524-528, 524-551, 68467-5, 67979-5, and 29964-4), and 

stacked (corn-borer/corn rootworm-protected) Bt corn products (EPA Reg. Nos. 524-545, 524-

552, 524-576, 68467-6, 67979-8, and 29964-5), the registrants must work together through their 

self-appointed Agricultural Biotechnology Stewardship Technical Committee (ABSTC) to 

implement an Insect Resistance Management (IRM) Compliance Assurance Program (CAP). 

The IRM CAP is designed to promote compliance with refuge requirements among all Bt corn 

growers irrespective of farm size. The program is composed of several parts: grower 

agreements, annual grower affirmation of IRM requirements, grower education, tips and 

complaints to identify non-compliant growers, third-party grower survey (telephone and, since 

2007, also on-line), on-farm assessments and follow-up actions (phased compliance program) 

should non-compliant growers be identified through the on-farm assessments. Individual 

registrants, however, are responsible for implementing the requirements agreed upon by the 

ABSTC-Insect Resistance Management Stewardship Subcommittee’s Compliance Assurance 

Program and EPA. Yearly results of the program are to be reported to EPA in an annual 

compliance assurance report (January 31st each year). This review addresses the 2009 Insect 

Resistance Management Compliance Assurance Program Report for Corn Borer-Protected Bt

Corn submitted by the ABSTC - Insect Resistance Management Stewardship Subcommittee. 

II. SUMMARY OF 2009 CAP 

The 2009 ABSTC CAP contained a summary of the following activities: 1) 2009 third party 

grower surveys for single and stacked PIPs targeting ECB and CRW, 2) 2009 on-farm 

assessments, 3) tips and complaints, 4) CAP activities for 2009, and 5) plans for the CAP 

during 2011. Grower agreements and annual grower affirmation systems are reviewed as part of 

each registrant’s annual IRM report. 

1. THIRD-PARTY GROWER PHONE AND ON-LINE SURVEY 

The grower survey functions to measure compliance adherence to refuge size and distance 

requirements in the Corn Belt and Cotton Belt and to identify educational opportunities to 

increase grower compliance with IRM requirements. As a condition of each individual Bt corn 

registration, the registrant must perform an annual third-party survey of a statistically 

representative sample of Bt corn growers. Beginning with the 2002 growing season, >500 

growers from four separate regions were anonymously surveyed. The methodology for 

conducting the grower survey has remained largely unchanged since it was first conducted by 

Marketing Horizons, Inc in 2000. Past results (including data from 2006) were weighted to 

reflect the actual distribution of corn acres in each region. However, starting in 2007 due to an 

increasing complexity of growers’ Bt corn planting practices and a need to standardize the 

grower survey across insect-protected traits, Marketing Horizons utilized an internet-based 

survey approach. BPPD notes that it is unclear at this point what kind of bias, if any, entered the 

data due to this change in methodology. In other words, a reported increase in non-compliance 

may or may not be partly due to the change in the survey methodology. 

- 3 -
There are several sampling regions that differ by pest and level of adoption: a) regions with 

high rates of Bt corn adoption; b) areas where insecticides have historically been sprayed for 

control of corn boring insect pests; and c) areas where Bt corn and Bt cotton may be grown 

simultaneously. To participate in the survey, respondents had to be identified as decisionmakers, not employed by the agrichemical or seed industries, who farmed a minimum of 200 

acres of corn (100 acres in the corn-cotton growing region of the South), and at least 50 acres of 

their total corn acreage had to be planted with Bt corn (the registered products identified in the 

subject heading). Due to the random nature of the survey, the sample size from cotton growing 

regions was too small in 2007 and 2008 to analyze whether there was a difference in 

compliance between the Cotton Belt and Corn Belt. ABSTC reported in its 2008 CAP that it 

will work with Marketing Horizons to improve the response rate in the cotton-growing regions 

for the 2009 surveys. 

On May 21, 2009 BPPD requested from ABSTC that survey data be collected on a regional 

basis and results subsequently reported as such. The regions and target number of growers from 

each region are outlined below: 

• Eastern Corn Belt (250 growers): primarily Indiana, Illinois, Wisconsin, Ohio, and 

Michigan 

• Western Corn Belt (250 growers): primarily Iowa, Nebraska, Minnesota, South 

Dakota, Missouri, and Kansas 

• Cotton-growing region (100 growers): as defined by EPA in Bt corn registrations 

To obtain statistically valid national results, survey results from the three regions were 

weighted according to the proportion of total US corn acres in each region. The number of 

growers needed to participate in the survey to ensure a statistically significant representation 

for overall sample size and product type were a minimum of 600 growers for the internet 

survey, and a minimum of 200 growers for both corn borer protected Bt corn and stacked Bt 

corn, as well as a minimum of 50 growers for rootworm protected Bt corn. 

Growers were recruited for the survey between August 24 and October 11, 2009; the internet 

based portion of the survey remained open for completion until October 18, 2009. A total of 

920 growers completed the internet survey in 2009, some of whom had multiple Bt corn 

varieties on their farms. The internet survey, therefore, resulted in 296 survey entries for single 

corn borer (ECB) protected PIPs, 61 entries for single corn rootworm (CRW) protected PIPs, 

and 563 entries for stacked corn PIPs protected against ECB and CRW. A total of 2981 on-farm 

assessments were conducted in 2009 with growers representing a range of farm sizes and states. 

The ABSTC compliance surveys were conducted for corn borer-protected, corn rootwormprotected, and stacked (corn borer- and rootworm-protected) Bt corn. The objectives of the 

surveys were to (i) determine the level of grower adherence to IRM requirements; (ii) measure 

changes in grower awareness of IRM requirements; (iii) obtain grower feedback for 

improvement of educational and compliance programs; and (iv) evaluate the potential 

biological significance of non-adherence to the requirements. 

- 4 -
a. CORN BORER-PROTECTED Bt CORN REGISTRATIONS 

2009 Data:

Of the 920 growers who completed the online survey, a total of 296 growers planted a corn 

borer protected Bt product in 2009 (single PIP but possibly also stacked PIP products). The 

compliance results listed here (Table 1) had a margin of error of ±5.7%. The survey results 

showed that adherence to the refuge size and distance requirements were 74% and 79%, 

respectively. An additional 10% of growers planted more than a 15% refuge but less than 20%, 

and 7% of growers surveyed failed to plant a refuge at all. Responses to survey questions about 

each field on a grower’s farm revealed that 92% of all fields planted to corn borer protected Bt 

corn had a refuge planted within the required 1⁄2 mile distance. Two percent of all fields had a 

refuge beyond 1⁄2 mile, and 5% of all fields had no refuge associated with them. 

On a regional basis, 77% and 76% of growers planted the correct refuge size and 84% and 79% 

adhered to the distance requirements in the eastern and western regions of the Corn Belt, 

respectively. In the cotton growing regions, 40% of growers met the refuge size requirements 

and 63% adhered to the distance requirements. 

When growers were asked on an unaided basis what they recalled about IRM requirements, 

64% and 82% correctly identified the refuge size and distance requirements, respectively. 

Table 1. Summary of telephone survey results for corn borer-protected Bt corn growers (Data from 2002-

2006) and online survey results (Data from 2007 and 2009)

Survey Question

Survey Year

Telephone Online 

2002 2003 2004 2005 2006 2007 2008 2009 

-----------% respondents----------- 

Adherence to Refuge Size

Weighted average across all four 

regions surveyed 

86 92 91 92 89 80 78 74% 

NC/SC/SE MO/TN/MS 

( 50% refuge in cotton-growing 

areas) 

77 82 78 82 80 

N/A N/A 

40% 

E IA/N IL (20% refuge) 88 96 95 94 

89-99 77% 

and 

76%* 

SD/MN/NE/W IA (20% refuge) 85 93 90 91 

KS/OK/TX (20% refuge) [High 

Plains] 

81 82 93 95 82 

Adherence to Distance Requirements 

Weighted average across all four 

Regions surveyed 

89 93 96 96 96 884 884 79%5

NC/SC/SE MO/TN/MS [Cotton 78 83 84 80 80 N/A N/A 63% 

- 5 -
 Region] 

E IA/N IL 95 96 96 97 

89-99 

84% 

and 

79%* 

SD/MN/NE/W IA 89 94 98 97 

KS/OK/TX [High Plains] 79 92 94 94 

Awareness of IRM Requirements

All growers 88 93 92 92 92 96 98 95% 

Unaided Recall of IRM Requirements

Refuge size (weighted average 

across all four regions surveyed) 

42 52 53 59 N/A 633 793 64% 

Refuge distance (weighted average 

 across all four regions surveyed) 

37 49 55 53 49 793 893 82% 

Refuge size (Corn Belt and High 

Plains) 1 61 N/A N/A N/A 

Refuge size (Cotton Belt)2 31 N/A N/A N/A 

1

Corn belt and high plains = Iowa, Illinois, South Dakota, Minnesota, Nebraska, Kansas, Oklahoma, Texas, i.e., three of four 

regions surveyed 

2

Cotton belt = North Carolina, South Carolina, south-eastern Missouri, Tennessee, and Mississippi 3 Cotton Belt numbers are not separated from Corn Belt survey results 

4

 Percent reflects only those growers that could remember the layout of all their Bt fields; 447 out of 467 (95.7%) in 2007; 298

out of 317 (94%) in 2008. 

5

 on a per field basis, adherence was 92% in 2009; 5% of the fields had no refuge. 

*States in the eastern region were primarily Indiana, Illinois, Wisconsin, Ohio, Michigan; states in the western region were 

primarily Iowa, Nebraska, Minnesota, South Dakota, Missouri, and Kansas.. 

b. CORN ROOTWORM-PROTECTED Bt CORN REGISTRATIONS 

2009 Data:

Of the 920 growers who completed the online survey, 61 growers planted coleopteran-protected Bt

corn (single PIP but possibly also stacked PIP products) and were randomly selected from the corn 

growing regions. All respondents planted a minimum of 200 acres of corn in 2008 (100 acres in the 

corn-cotton growing region of the South), with a minimum of 50 acres of rootworm-protected corn. 

The compliance results listed here (Table 2) had a margin of error of ±12.6 %. 

Reported results showed that grower adherence with planting the correct refuge size and observing 

the correct distance requirement was 79% and 71%, respectively. An additional 7% of growers 

planted more than a 15% refuge but less than 20%, and 9% of growers surveyed failed to plant a 

refuge at all. 

Responses to survey questions about each field on a grower’s farm revealed that 76% of all fields 

planted to corn borer protected Bt corn had a refuge planted within the Bt field or adjacent. Ten 

- 6 -
percent of all fields had a refuge not near the Bt field, and 14% of all fields had no refuge 

associated with them. 

A regional breakdown of rootworm protected Bt corn responses was not available because of an 

insufficient sample size of respondents. 

When growers were asked on an unaided basis what they recalled about IRM requirements, 58% 

and 31% correctly identified the refuge size and distance requirements, respectively. 

Table 2. Percent Respondents for Different Questions of Telephone (2005-2006) and Online Survey (2007-2009) 

for Rootworm-Protected Bt Corn Growers 

Survey Question3 20051 20062 2007 2008 2009 

Adherence to Refuge 93% 89% 80% 74% 79% 

Adherence to Distance 

 Requirements

87% 82% 79% 63% 71%4

Awareness of IRM 

Requirements

97% 93% 97% 96% 92% 

Unaided recall of 

refuge size

51% 57% 63% 72% 58% 

Unaided recall of 

refuge distance

58% 55% 33% 34% 31% 

 1YieldGard RW and YieldGard Plus corn growers 2YieldGard RW, YieldGard Plus, Herculex RW, and Herculex XTRA corn growers. 3Weighted average across all four regions surveyed 4 on a per field basis, adherence was 76% in 2009; 14% of the fields had no refuge.

c. STACKED Bt CORN REGISTRATIONS 

2009 Data: 

Of the 920 growers who completed the online survey, 563 planted stacked Bt corn (for ECB and/or 

CRW control). The compliance results reported in Table 3 had a margin of error of ±4.2 %. 

Reported results showed that adherence to the refuge size and distance requirements were 71% and 

67%, respectively. ABSTC reported that this was a significant improvement compared to the 

survey results obtained in 2008. An additional 8% of growers planted more than a 15% refuge but 

less than 20%, but 11% of growers surveyed failed to plant a refuge at all. 

Responses to survey questions about each field on a grower’s farm revealed that 78% of all fields 

planted to corn borer protected Bt corn had a refuge planted within the required 1⁄2 mile distance. 

Ten percent of all fields had a refuge beyond 1⁄2 mile, and 12% of all fields had no refuge 

- 7 -
associated with them. 

On a regional basis, 74% and 73% of growers planted the correct refuge size and 66% and 70% 

adhered to the distance requirements in the eastern and western regions of the Corn Belt, 

respectively. In the cotton growing region, 31% of growers met the refuge size requirements and 

63% adhered to the distance requirements. 

When growers were asked on an unaided basis what they recalled about IRM requirements, 66% 

and 59% correctly identified the refuge size for ECB and CRW, respectively. On an unaided basis, 

83% and 32% of growers correctly identified the ECB and CRW distance requirements, 

respectively. 

Table 3. Percent Respondents from Different Question of Telephone and On-Line Survey for Stacked Bt Corn 

Growers (Data from 2006-2009)

Survey Question 

2006 2007 2008 2009 

Adherence to Refuge Size1 78% 70% 72%4 71%

Adherence to Distance 

Requirements

92% 66% 66%3 67%3

Awareness of IRM Requirements 95% 96% 97% 95%

Unaided recall of refuge size 59% 62% and 55%2

81% 66% and 59%2

Unaided recall of refuge distance 

CRW 

48% 39% 36% 32%

Unaided recall of refuge distance 

ECB 

32% 77% 86% 83%

1 Weighted average across all four regions surveyed 

2 First number listed is for ECB and the second number for CRW refuge compliance. 3

 on a per field basis, adherence was76% in 2008 and 78% in 2009 

4

 on a per field basis, adherence was 73% 

d. BPPD REVIEW OF ON-LINE GROWER SURVEY RESULTS (2009) 

The survey results (see Figure 1) show that average compliance across all corn growing regions 

with refuge size requirements for ECB protected corn expressing single PIPs is lower than in the 

previous two years (74% in 2009, 78% in 2008, and 80% in 2007). Growers reported to be out of 

compliance deviated from the 20% requirement in one way or another. Further analysis of noncompliance numbers revealed that most farmers (84%) planted a refuge that was at least 15%, and 

that only 7% of farmers neglected to plant a refuge at all. Growers’ adherence to the 1⁄2 mile refuge 

distance requirement decreased from 88% in 2007 and 2008 to 79% in 2009. The margin of error 

for 2009 single ECB PIP results is ±5.7%, and therefore, 2009 compliance results do not differ 

significantly from the 2007 and 2008 results. A regional analysis revealed that growers planting 

single ECB PIP expressing corn in eastern and western regions of the Corn Belt adhered about 

- 8 -
equally to refuge size (77% and 76%) and distance requirements (84% and 79%), while the corn 

growers in the southern U.S. had significantly lower adherence percentages (40% with refuge size 

and 63% with refuge distance). Some of this observed difference could be due to differences in 

sample sizes. The sample size for southern corn growers was 60% reduced compared to growers in 

the eastern and western regions of the US who took the online survey. Other explanations for such 

lower compliance in the south could be attributed to some possible 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 non-compliance among southern corn 

growers reflects a willingness to violate refuge requirements 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. 

Figure 1. Compliance Trend from 2002 - 2009 for ECB protected Corn PIPs 

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

displayed in Figure 2. Average compliance in 2009 with refuge size (79%) and refuge distance 

(71%) , respectively and was unchanged from prior years (margin of error = ±12.6%). On a per 

field basis, 100% compliance with refuge size was similar to per-grower results. When the number 

of Bt fields that had at least 15% refuge associated with them were considered, then compliance 

increased to 86%. 

Grower awareness with IRM requirements in 2009 was unchanged from 2008, but only 58% of 

growers surveyed were able to recall the correct refuge size requirement in 2009, a decline of 14% 

compared to 2008. BPPD believes that this decline is reason for concern. Educational efforts may 

need to target growers planting single CRW PIPs. 

- 9 -
Figure 2. Compliance Trend from 2005-2009 for CRW protected PIPs 

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

Figure 3. In 2009, the margin of error for adherence with requirements was ±4.2%; therefore, 

BPPD concludes that the latest average compliance results for refuge size and refuge distance were 

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

planting stacked corn PIPs in eastern and western regions of the U.S. adhered about equally to 

refuge size (74% and 73%) and distance requirements (66% and 70%), while the corn growers in 

the southern U.S. had significantly lower adherence percentages (31% with refuge size and 63% 

with refuge distance). Adherence percentages with refuge size in eastern and western US corn 

growing regions were similar for stacked and single ECB PIPs, while percentages for refuge 

distance with stacked PIPs were lower. Greater educational efforts may have to focus more on the 

refuge distance requirement for stacked PIP products due to the increased requirement complexity 

for stacked products; the lower compliance with stacked IRM requirements could also include other 

factors such as challenges with planting a refuge due to weather. On the other hand, growers’ 

adherence with refuge size and distance requirements was again much lower in the south compared 

to the northern growers’ compliance. As stated earlier in this review, ABSTC may need to consider 

other methods, aside from increased education, to bring southern growers into compliance with 

IRM requirements. Higher non-compliance among southern corn growers could reflect willful noncompliance rather than a lack of knowledge. 

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

unaided basis was relatively low for stacked products. This provides further opportunity for 

ABSTC to increase grower education. 

 

- 10 -
Figure 3. Compliance Trend from 2006-2009 for Stacked Corn PIPs 

2. On-Farm Assessment Program 

The on-farm assessment portion of the Compliance Assurance Program identifies individual noncompliant growers (large and small farms) and brings them back into compliance through the 

Phased Compliance Approach. This part of the CAP is believed to enhance registrant and seed 

dealer understandings of the obstacles that hinder grower implementation of IRM requirements. 

Unlike the online grower survey, the on-farm assessment program is not a statistical tool for 

measuring the level of adherence to the IRM requirements. 

Registrants and their seed company partners independently coordinate the on-farm assessment 

activities each year. Growers receiving “first-time” on farm assessments (i.e. not assessed the 

previous year) were selected from individual company customer lists and included a range of farm 

sizes across a number of key states. Growers found to be out of compliance in 2008 received a 

follow-up on-farm assessment in 2009. 

Company representatives were trained to conduct on-farm assessments. Topics covered in these 

trainings included IRM requirements, messages that should be communicated to growers, followup actions if growers are found to be out of compliance and how to use the IRM assessment form. 

All assessment forms contained the same questions, but the introductory paragraphs and company 

representative sections were customized to suit the needs of each registrant. Registrants responded 

to all compliance deviations identified in the 2007 and 2008 on-farm assessments according to the 

common set of standards outlined in the PCA (see Appendix). 

The number of growers of each type of Bt corn who were assessed varied due to the market size of 

each product type. In 2009, 2981 growers received a first time assessment. 

In 2008, 452 growers were found to be out of compliance, of which 331 had significant deviations. 

All compliance deviations were responded to in accordance with the Phased Compliance Approach, 

- 11 -
including reassessment in 2009. Three growers met the criterion for revocation of access to stacked 

Bt corn according to EPA requirements. Growers planting single and stacked ECB and CRW Bt 

corn and who were out of compliance in 2008 were either successfully brought back into 

compliance in 2009, or no longer farmed or planted Bt corn in 2009. 

a. On-farm assessment results for growers planting ECB protected Bt corn products 

2009 Data:

Of the 1082 growers planting corn borer protected Bt corn and having received a first-time on-farm 

assessment in 2009, 83.6% were fully compliant with refuge requirements (see Table 4). Of the 

16.4% non-compliant growers, 10.8% had significant deviations. On-farm assessments were 

conducted across a range of farm sizes with approximately 33% of growers categorized as “small 

growers” with less than 250 acres of corn. As with previous years, the data suggest that farm size 

should not be a selection criterion when trying to identify non-compliant growers. 

Table 4. Cumulative Results for the First-Time On-Farm Lepidopteran-Protected Bt Corn Assessments (Data 

for 2003-2009) 

Issue addressed Number of growers 

2003 2004 2005 2006 2007 2008 2009 

Growers assessed 1961 2130 2215 2020 2083 1312 1082 

Compliant 

growers 

1,789 

(91%) 

2032 

(95.4%) 

2089 

(94.3%) 

1930 

(95.5%) 

1895 

(91.0%) 

1132 

(86.3%) 

905 

(83.7%) 

Noncompliant 

growers

172 

(9%) 

98 

(4.6%) 

126 

(5.7%) 

90 

(4.5%) 

188 

(9.0%) 

180 

(13.7%) 

177 

(16.4%) 

Refuge size 

deviations* 64 (3%) 27 (1.3%) 33 (1.5%) 33 (1.6%) N/A N/A N/A

Refuge distance 

deviations 127 (7%) 69 (3.2%) 68 (3.1%) 64 (3.2%) N/A N/A N/A

Insignificant 

deviations 68 (4%) 59 (2.8%) 51 (2.3%) 45 (2.2%) 59 (2.8%) 46 (3.5%) 60 (5.6%) 

Significant 

deviations2 104 (5%) 39 (1.8%) 75 (3.4%) 45 (2.2%) 129 (6.2%) 134 (10.2%) 117 (10.8%) 

1 Some growers had compliance deviations other than refuge size or distance or some growers may have had both a refuge size and a

refuge distance deviation; thus, the total of refuge distance and size deviations does not equal the number of non-compliant growers. 2 Significant deviations are defined as: A Bt corn grower who planted less than 15% non- Bt corn refuge (except in certain cotton 

growing areas in which case it would be less than 40% non- Bt corn refuge); or planted fewer than 2/3 of the Bt corn fields are 

planted within 2 mile of a non- Bt corn refuge. 

- 12 -
b. ON-FARM ASSESSMENT RESULTS FOR GROWERS PLANTING CRW 

PROTECTED Bt CORN PRODUCTS 

2009 Data: 

Of the 110 growers planting corn borer protected Bt corn and having received a first-time on-farm 

assessment in 2009, 69.1% were fully compliant with refuge requirements. Of the 30.9% noncompliant growers, 26.4% had significant deviations. On-farm assessments were randomly 

conducted across a range of farm sizes with approximately 33% of growers categorized as “small 

growers” with less than 250 acres of corn. As with previous years, the data suggest that farm size 

should not be a selection criterion when trying to identify non-compliant growers. 

Table 5. Cumulative Results for the On-Farm Coleopteran-Protected Bt Corn Assessment1 (2006-2009 data) 

Issue addressed 2006 2007 2008 2009 

Growers assessed 395 247 134 110 

Refuge distance 

deviations 132 N/A N/A N/A

Refuge size deviations 7 N/A N/A N/A

Significant deviations 113

 (2.8%) 16 (6.5%) 12 (9.0) 29 (26.4%) 

Insignificant 

deviations 

10 (4.0%) 8 (3.2%) 7 (5.2%) 5 (4.5%) 

Compliant growers 374 (94.7%) 223 (90.3%) 115 (85.8%) 76 (69.1%) 

Non-compliant 

growers 

21 (5.3%) 24 (9.7%) 19 (14.2%) 34 (30.9%) 

1

Table adapted from page 12 of MRID 470444-01 

2

 Some growers had compliance deviations other than refuge size or distance; thus, the total of refuge distance and size 

deviations does not equal the number of non-compliant growers. 

3 Significant deviations are defined as: A Bt corn grower who planted less than 15% non- Bt corn refuge (except in certain 

cotton growing areas in which case it would be less than 40% non- Bt corn refuge); or planted fewer than 2/3 of the Bt corn 

fields are planted within 2 mile of a non- Bt corn refuge. 

c. ON-FARM ASSESSMENT RESULTS FOR GROWERS PLANTING STACKED Bt 

CORN PRODUCTS 

2009 Data: 

Of the 1789 growers planting corn borer protected Bt corn and having received a first-time on-farm 

assessment in 2009, 83.3% were fully compliant with refuge requirements. Of the 16.7% noncompliant growers, 11.4% had significant deviations. On-farm assessments were randomly 

conducted across a range of farm sizes with approximately 33% of growers categorized as “small 

growers” with less than 250 acres of corn. As with previous years, the data suggest that farm size 

should not be a selection criterion when trying to identify non-compliant growers. 

- 13 -
Table 6. Cumulative Results of the First Time On-Farm Stacked Bt Corn Assessment1

 (Data for 2006-2009) 

Issue addressed 2006 2007 2008 2009 

Growers assessed 600 1069 1799 1789 

Refuge distance 

deviations 512 N/A N/A N/A

Refuge size deviations 8 N/A N/A N/A

Significant deviations 453

 (7.5%) 77 (7.2%) 86 * 193 (10.8) 

Insignificant 

deviations 

16 33 (3.1%) 36* 106 (5.9%) 

Compliant growers 539 (89.8%) 959 (89.7%) 1546 (85.9%) 1490 (83.3%) 

Non-compliant 

growers 

61 (10.2%) 110 (10.3%) 253 (14.1%) 299 (16.7%) 

1

Table adapted from page 12 of MRID 470444-01 

2

 Some growers had compliance deviations other than refuge size or distance; thus, the total of refuge distance and size deviations 

does not equal the number of non-compliant growers. 3 Significant deviations are defined as: A Bt corn grower who planted less than 15% non- Bt corn refuge (except in certain cotton 

growing areas in which case it would be less than 40% non- Bt corn refuge); or planted fewer than 2/3 of the Bt corn fields are 

planted within 2 mile of a non- Bt corn refuge. 

* The numbers of deviations to not add up to the 253 non-compliant cases reported. 

d. BPPD REVIEW OF ON-FARM ASSESSMENT RESULTS (2009)

ABSTC states that “the on farm assessment program is not a statistical tool for measuring the level 

of adherence to the IRM requirements”, and that rather, “this program helps identify obstacles that 

hinder grower implementation of IRM requirements”. BPPD notes that a comparison between 

year-to-year on-farm survey results then should be made with caution because, among other things, 

the growers were not randomly selected from companies’ customer lists. Nonetheless, it is difficult 

to ignore that that on-farm compliance for CRW protected traits in 2008 was 85.8% and 69% in 

2009, and that the percentage of significant violations in 2008 were 9% and 26.4% in 2009. BPPD 

is aware that companies do not share their clientele list with each other and that names and 

locations of non-compliant growers are confidential and anonymous for the Agency. Yet, BPPD 

proposes that ABSTC compile and maintain, through a neutral third party, maps showing the 

distribution of on-farm non-compliance pooled across registrants so that it is clear to the BPPD 

IRM team where these non-compliant regions are in the Corn Belt. It may then be possible for 

ABSTC to increase compliance in these regions with increased educational outreach by the 

registrants or other appropriate new measures. 

On-farm compliance results for stacked lepidopteran and coleopteran protected PIP as well as 

single ECB PIP products continue to be lower each year as is evident from the results listed in 

Tables 4 and 6. The percentage of non-compliant growers and growers having significant 

deviations is increasing each year as well. BPPD notes that this slight downward trend in on-farm 

compliance should be taken seriously. The decreasing compliance since 2006 is relatively small yet 

steady. As is visible in Table 6, on farm assessments for stacked products showed that 89.8% of 

growers (sample size 600) were compliant in 2006, while by 2009 the percentage reached 83.3% 

(non-random sample size of 1789). Likewise, Table 4 shows that there has been a steady and 

decreasing trend in on-farm non-compliance with single PIP products targeting ECB: in 2006 

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compliance was 91% (sample size 1961) and reached 83% in 2009 (non-random sample size of 

1082). 

On-farm compliance results for single PIP products targeting CRW are cause for increased 

concern: grower compliance has dwindled from 85.8% in 2008 (sample size 134) to 69.1% in 2009 

(non-random sample size of 110). That is more than a 15% decrease in compliance in just one year 

(although the numbers likely do not represent an average of the same population). Percentage of 

significant deviations was 9% in 2008 and 26% in 2009. Since on-farm assessments have been 

implemented in 2006, compliance has decreased each year and is now 20% less in 2009 than it was 

in 2006. BPPD recommends that ABSTC meet with the BPPD IRM team to address future steps to 

improve compliance. 

Additional compliance requirements (i.e. bag tags) were implemented with the 2010 Bt corn 

extensions. These measurements could improve future compliance beginning in the 2011 growing 

season. 

3. TIPS AND COMPLAINTS

2009 Data: 

In 2009, the registrants received four “tips and complaints.” Legitimate tips and complaints were 

managed in accordance with the Compliance Assessment Program. Any grower found to be out of 

compliance based on a legitimate tips and complaint received an on-farm IRM visit. If there were 

any growers found to be out of compliance during the visit then these growers were responded to in 

a manner consistent with the Phased Compliance Approach. 

Table 7. Anonymous Tips and Complaints about Non-Compliance with IRM requirements 

Year Number of Tips and 

Complaints 

2009 4 

2008 5 

2007 14 

2006 3 

2005 5 

2004 0 

2003 0 

4. PUBLICIZING THE COMPLIANCE ASSURANCE PROGRAM

The registrants publicize the CAP, including the Phased Compliance Approach as part of each of 

their grower education programs, company literature, internal training sessions, and meetings with 

growers and dealers. ABSTC members also work with the National Corn Growers Association. 

The registrants work to provide the growers a consistence message about compliance with IRM 

requirements. 

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5. ABSTC OVERAL CONCLUSIONS

The registrants who are part of the ABSTC conclude that based on the 2009 third party internet 

survey and registrant conducted on-farm assessments, the different programs of the CAP continue 

to be effective. In 2009 between 70 and 80% of all growers surveyed planted the required size 

refuge and between 67 and 78% of growers planted a refuge within the required distance of their Bt 

fields. The survey indicates that the vast majority of all Bt corn fields (86% to 95%) have an 

associated refuge. These findings are similar to those obtained in 2007 and 2008; there appears, 

however, to be a small improvement with adherence to refuge requirements for CRW protected Bt 

corn. Overall compliance percentages continue to be lower for ECB protected Bt corn in recent 

years than historically observed in 2002 through 2006. 

The data suggest that the occurrence of significant areas of Bt corn planted without a refuge was 

rare. When the refuge requirements were established, the EPA recognized that 30% (or higher) of 

non-compliance could be a reasonable expectation (USEPA 2001). Resistance monitoring 

programs based on field observations and population sampling continue to show that the key target 

pests of the Bt corn products remain susceptible to the insecticidal proteins. 

A regional analysis of the grower survey results presented no clear differences in adherence to the 

refuge requirements between growers of the eastern and western Corn Belt. However, the growers 

in the southern cotton-growing region showed lower levels of adherence. Several reasons for lower 

adherence to refuge requirements in the South have previously been proposed including practical 

limitations resulting from the larger refuge size required for ECB protected Bt corn, smaller farm 

sizes, greater diversity and complexity in farm operations, a different pest spectrum, and the 

smaller role that corn plays in overall agricultural production of the South. The 2009 survey results 

also indicated that a greater proportion of growers were unaware of refuge requirements compared 

to their northern counter-parts, and fewer were able to recall the specific refuge requirements on an 

unaided basis. These findings present an opportunity for ABSTC and member companies to 

strengthen grower IRM education efforts of that region. 

6. BPPD REVIEW OF OVERALL CAP 

BPPD concurs with ABSTC that the majority of growers who planted single trait and stacked 

ECB/CRW PIP products were compliant with the refuge requirements in 2009 when national 

average results from the on-line survey were considered. Although the degree of non-compliance in 

2009 is in some instances lower than in 2008, it is not clear that these differences are statistically 

significant. When on-line compliance results were evaluated on a regional basis, however, it was 

evident that southern corn growers were up to 2.4 times less compliant than their northern 

counterparts. BPPD is concerned with these findings and recommends that ABSTC propose 

alternative approaches to increase refuge compliance in the southern corn growing regions of the 

U.S. 

ABSTC concluded that compliance with CRW protected PIPs has seen some improvements. It is 

correct that compliance with refuge size and distance was somewhat higher in 2009 compared to 

2008. However, the margin of error for adherence with requirements was ±12%, and the increase in 

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compliance seen in 2009 was below that reported margin of error. Hence it is not possible to 

conclude that there was an actual improvement with adherence to refuge requirements for single 

CRW corn PIPs. 

In contrast to the online survey program, ABSTC states that “the on farm assessment program is 

not a statistical tool for measuring the level of adherence to the IRM requirements”, and that rather, 

“this program helps identify obstacles that hinder grower implementation of IRM requirements”. 

BPPD notes that a comparison between year-to-year on-farm survey results then should be made 

with caution because, among other things, the growers were not randomly selected from 

companies’ customer lists. Nonetheless, it is difficult to ignore that that on-farm compliance for 

CRW protected traits in 2008 was 85.8% and 69% in 2009, and that the percentage of significant 

violations in 2008 were 9% and 26.4% in 2009. BPPD is aware that companies do not share their 

clientele list with each other and that names and locations of non-compliant growers are 

confidential and anonymous for the Agency. Yet, BPPD proposes that ABSTC compile and 

maintain, through a neutral third party, maps showing the distribution of on-farm non-compliance 

pooled across registrants so that it is clear to the BPPD IRM team where these non-compliant 

regions are in the Corn Belt. It may then be possible for ABSTC to increase compliance in these 

regions with increased educational outreach by the registrants or other appropriate new measures. 

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REFERENCES

Bogdanova N, D Guyer, MJ Smith, and N Storer. 2009. Insect Resistance Management Compliance 

Assurance Report for Corn Borer-Protected Bt Corn, Corn Rootworm-Protected Bt corn, and Corn 

Borer/Corn Rootworm-Protected Stacked Bt Corn. Unpublished report submitted by ABSTC to the 

Agency. MRID 479710-01 

U. S. Environmental Protection Agency (EPA) 2001. Biopesticides Registration Action 

Document: Bacillus thuringiensis Plant-Incorporated Protectants (10/16/01), posted at 

http://www.epa.gov/pesticides/biopesticides/pips/bt_brad.htm. 

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APPENDIX: Phase Compliance Approach (PCA) 

The ABSTC - IRM Subcommittee has developed a standard set of procedures (Table 8) 

known as the Phased Compliance Approach (PCA). The PCA requires that registrants take specific 

actions (primarily, remedial grower education and then loss of access to the technology if an 

individual grower is found to have significant deviations in two consecutive years) for noncompliant growers identified through the on-farm assessment program. The PCA proposes to 

suspend sales to individual growers for one year after two years of significant deviations. 

Following the one-year suspension, growers may be re-qualified to purchase seeds. 

Table 2. Phased Compliance Approach (PCA)

Mandatory Responses Additional Responses 

Significant Deviations • IRM education 

• Warning letter 

• Compliance assistance contact prior to 

planting 

• Compliance assessment contact for the 

following growing season 

• Deny access to the Bt corn product for 

any significant deviation two years in a 

row 

• Invoice monitoring 

• Technical assistance 

• Grower IRM training 

• Reaffirmation of IRM 

obligations 

• Deny access to the Bt corn 

product for other deviations 

that are repeated over a 

period of years 

Other Deviations • IRM education 

• Letter and/or compliance assistance 

contact prior to planting 

• Compliance assessment contact in the 

following growing season