FOR PUBLICATION

UNITED STATES COURT OF APPEALS

 FOR THE NINTH CIRCUIT

NATIONAL FAMILY FARM

COALITION; CENTER FOR FOOD

SAFETY; CENTER FOR BIOLOGICAL

DIVERSITY; PESTICIDE ACTION

NETWORK NORTH AMERICA, 

Petitioners,

 v.

U.S. ENVIRONMENTAL PROTECTION

AGENCY; ANDREW WHEELER, in his

official capacity as Administrator, 

Respondents,

MONSANTO COMPANY, 

Respondent-Intervenor.

No. 19-70115

Environmental Protection Agency

OPINION

On Petition for Review of an Order of the

U.S. Environmental Protection Agency

Argued and Submitted April 21, 2020

San Francisco, California

Before: Michael Daly Hawkins, M. Margaret McKeown, and William A. Fletcher,

Circuit Judges.

Opinion by Judge W. Fletcher

FILED

JUN 3 2020

MOLLY C. DWYER, CLERK

U.S. COURT OF APPEALS

1
American farmers have been using dicamba, a chemical herbicide, to combat

weeds for more than fifty years. Dicamba is an effective weed killer, but its

toxicity is not limited to weeds. It can kill many desirable broadleaf plants, bushes,

and trees. It also has a well-known drawback. Dicamba is volatile, moving easily

off a field onto which it has been sprayed. It can drift if the wind blows during

application; it can drift if applied during temperature inversions; it can drift after

application when it volatilizes, or turns to a vapor, during hot weather. As a result

of its toxicity and its tendency to drift, dicamba had historically been used to clear

fields, either before crops were planted or before newly planted crops emerged

from the soil. This changed in 2017. 

By the early 2000s, many weeds had developed a resistance to the widely

used herbicide glyphosate, the main ingredient in Roundup brand-name products

sold by the Monsanto Company (“Monsanto”). In response, Monsanto developed

and patented genes that allowed soybean and cotton crops to tolerate dicamba. 

Concurrently, Monsanto and two other herbicide manufacturers reformulated

dicamba herbicides in an attempt to make dicamba less volatile and therefore

usable during the growing season. Their efforts culminated in 2016, when,

pursuant to the Federal Insecticide, Fungicide, and Rodenticide Act (“FIFRA”), 7

U.S.C. §§ 136 et seq., the U.S. Environmental Protection Agency (“EPA”) granted

conditional, two-year amended registrations to Monsanto and later the two other

2
agrochemical companies, approving their reformulated dicamba-based herbicides

for over-the-top (“OTT”), or “post-emergent” use on dicamba-tolerant (“DT”)

soybeans and cotton ahead of the 2017 growing season. The conditional

registrations were to expire in late 2018.1 

On October 31, 2018, the EPA approved conditional registrations for the

three dicamba-based herbicides for an additional two years. The EPA’s decision

document announced that the EPA “will be granting requests by Bayer

CropScience (formerly Monsanto Company), Corteva (formerly DuPont), and

BASF to amend their existing conditional registrations that contain expiration

dates of November 9, 2018, and December 20, 2018, respectively.” In the

following week, the EPA issued conditional two-year amended registrations to

Bayer for its “M1768 Herbicide,” also known as “XtendiMax With VaporGrip

Technology” (“XtendiMax”); to Corteva for its “DuPont FeXapan Herbicide”

(“FeXapan”); and to BASF for its “Engenia Herbicide” (“Engenia”).

The National Family Farm Coalition, Center for Food Safety, Center for

Biological Diversity, and Pesticide Action Network North America (“petitioners”)

sought review of the October 31, 2018, decision upon which the registrations were

1 For the convenience of the reader, we list here the key abbreviations used in this

opinion. “Over-the-top” (dicamba use) is abbreviated “OTT.” “Dicamba-tolerant”

(soybean and cotton) is abbreviated “DT.” The Office of Pesticide Programs

(housed within the EPA) is abbreviated “OPP.”

3
based. Petitioners argue that the EPA’s decision violates both FIFRA and the

Endangered Species Act, 16 U.S.C. § 1536(a)(2). 

We hold that the EPA’s October 31, 2018, decision, and the conditional

new-use registrations of XtendiMax, Engenia, and FeXapan for use on DT soybean

and cotton that are premised on that decision, violate FIFRA. As we will explain

in more detail below, FIFRA provides two requirements for conditional

amendment of an existing registration. The EPA must determine that (i) the

applicant has submitted “satisfactory data,” and (ii) the amendment will not

“significantly increase the risk of any unreasonable adverse effect on the

environment.” 7 U.S.C. § 136a(c)(7)(B). We need not decide whether substantial

evidence supports a finding that the applicants submitted satisfactory

data—although, as we discuss below, the data have several flaws—because we

hold that the EPA substantially understated risks that it acknowledged and failed

entirely to acknowledge other risks. 

The EPA substantially understated three risks that it acknowledged. The

EPA substantially understated the amount of DT seed acreage that had been

planted in 2018, and, correspondingly, the amount of dicamba herbicide that had

been sprayed on post-emergent crops. Further, the EPA purported to be agnostic

as to whether formal complaints of dicamba damage under-reported or overreported the actual damage, when record evidence clearly showed that dicamba

4
damage was substantially under-reported. Finally, the EPA refused to estimate the

amount of dicamba damage, characterizing such damage as “potential” and

“alleged,” when record evidence showed that dicamba had caused substantial and

undisputed damage. 

The EPA also entirely failed to acknowledge three other risks. The EPA

entirely failed to acknowledge record evidence showing the high likelihood that

restrictions on OTT dicamba application imposed by the 2018 label would not be

followed. The EPA based its registration decision on the premise that the label’s

mitigation measures would limit off-field movement of OTT dicamba. These

measures became increasingly restrictive with each iteration of OTT dicamba

labels. Record evidence shows that the restrictions on the 2016 and 2017 labels

had already been difficult if not impossible to follow for even conscientious users;

the restrictions on the 2018 label are even more onerous. Further, the EPA entirely

failed to acknowledge the substantial risk that the registrations would have anticompetitive economic effects in the soybean and cotton industries. Finally, the

EPA entirely failed to acknowledge the risk that OTT dicamba use would tear the

social fabric of farming communities. 

We therefore vacate the EPA’s October 31, 2018, registration decision and

the three registrations premised on that decision. Because our vacatur is based on

5
our holding under FIFRA, we do not reach the question whether the registration

decision also violates the Endangered Species Act. 

I. Background

A. Evolution of Glyphosate-Resistant Weeds 

Before its purchase by Bayer in 2018, Monsanto had become a household

name largely due to its flagship herbicide Roundup. In the 1990s, Monsanto

developed a “Roundup Ready” crop system, selling this glyphosate-based

herbicide along with seeds genetically modified to tolerate glyphosate. 

Monsanto’s Roundup Ready system allowed farmers to apply glyphosate over

genetically modified crops during the growing season, killing weeds but leaving

their crops unharmed. By 2008, 92 percent of soybeans and 68 percent of cotton

plantings in the United States came from glyphosate-resistant seeds. Glyphosate

was so popular that many farmers sold their weed-tilling equipment and stopped

buying other herbicides, instead applying glyphosate on their fields year after year.

After years of heavy glyphosate use by farmers, many weeds developed

glyphosate resistance. Such “superweeds” include Palmer amaranth, a large and

fast-growing weed that, left unchecked, can take over a field. In search of a new

weed-killer, Monsanto and other agrochemical companies turned to dicamba,

which had been registered for limited use since 1967. Dicamba works by

mimicking auxin, a plant hormone, to cause abnormal and ultimately fatal cell

6
growth. Dicamba is extremely toxic to broadleaf plants, bushes, and trees. It can

damage or kill fruiting vegetables, fruit trees, grapes, beans, peas, potatoes,

tobacco, flowers, and ornamental plants. It can also damage or kill many species

of large trees, including oaks, elms, and maples. Dicamba damage is easily

identified by its signature marker, “leaf cupping.”

Dicamba’s toxic effect is magnified by its tendency, shared with other

synthetic auxins, to move off a field where it is sprayed. Dicamba droplets can

drift during or shortly after spraying if the wind is blowing too hard or the spraying

equipment is moving too fast. Dicamba vapor can drift if dicamba is applied

during a temperature inversion—an atmospheric condition in which cool air at the

earth’s surface traps warmer air above it, allowing the vapor to remain in a

concentrated cloud and move off-field during a light wind. And dicamba vapor

can drift if dicamba volatilizes after it has come to rest on plants or the ground. 

Dicamba can volatilize hours or even days after it has been applied, and it does so

more easily and in greater volumes as the temperature rises. During temperature

inversions, or after volatilizing on hot days, dicamba can drift long distances,

sometimes a mile or more.

Because of its tendency to drift, dicamba had been largely used in late winter

or early spring before crops were planted. Post-emergent use of dicamba was

7
limited to crops that are naturally tolerant of dicamba, such as corn and wheat, and

was typically limited to use early in the growing season. 

B. Development of Lower-Volatility Dicamba Herbicides

 and EPA’s 2016 Two-Year Conditional Registration Decision

Monsanto and two other agrochemical companies—DuPont and

BASF—developed new dicamba products with reduced (though not eliminated)

volatility. The companies claimed to the EPA that their new dicamba herbicides

had such low volatility that they were unlikely to move in significant amounts off

the field to which they were applied and could therefore be used safely during the

growing season. In 2010 and 2012, Monsanto submitted applications to the EPA

to register two different formulations of dicamba-based herbicide for postemergent use on genetically modified, dicamba-tolerant (“DT”) soybeans and

cotton. 

In 2015, the U.S. Department of Agriculture deregulated DT soybean and

cotton seeds under authority granted by the Plant Protection Act, 7 U.S.C. §§ 7701

et seq. Monsanto, which had developed and patented the dicamba-tolerance seed

trait, began to sell these DT seeds ahead of the 2016 growing season, before the

companion dicamba herbicides had been approved by the EPA for over-the-top

(“OTT”) use. Farmers planted about 1.7 million acres of DT soybeans and close to

50,000 acres of DT cotton in 2016. Record evidence contains reports that some

8
growers illegally sprayed the old dicamba herbicides during the post-emergent

phase of the 2016 growing season.

Under FIFRA, the EPA can conditionally amend the registration of a

pesticide (including an herbicide) to permit an additional use only if it finds that

the new use will not significantly increase the risk of any unreasonable adverse

effect on humans or the environment, taking into account the pesticide’s economic,

social, and environmental costs and benefits. See 7 U.S.C. § 136a(c)(7)(B)

(allowing the EPA to conditionally amend the registration of a pesticide to allow

for a new use); § 136(bb) (defining “unreasonable adverse effects on the

environment” to include “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”).

Beginning in the fall of 2016, the EPA announced that it would grant twoyear conditional registrations for three lower-volatility, OTT dicamba

herbicides—Monsanto’s XtendiMax; DuPont’s FeXapan; and BASF’s Engenia. In

support of its decision, the EPA identified two “important” benefits from OTT

application of dicamba on DT soybeans and cotton. First, dicamba “provides an

effective tool to treat especially noxious weeds . . . including glyphosate-resistant

biotypes that threaten soybean and cotton production today.” Second, “effective

treatment of glyphosate-resistant weeds can help control the spread of resistance.”

9
The EPA stated that the lower-volatility dicamba formulations, if used in

compliance with restrictions on an approved label, posed little or no risk of adverse

effects on the environment and therefore imposed minimal costs. In its registration

decision, the EPA wrote that the label restrictions “are known to profoundly impact

any drift potential from pesticide application.” “In aggregate, these formulations

and labeling requirements are expected to eliminate any offsite exposures and

effectively prevent risk potential to people and non-target species.” The EPA

concluded, “After weighing all the risks of concern against the benefits of the new

uses, the EPA finds that when the mitigation measures for these uses are applied,

the benefits of the use of the pesticide outweigh[] any remaining minimal risks, if

they exist at all.”

The conditional registrations allowed OTT dicamba use in thirty-four states.2

The conditional registrations for XtendiMax and FeXapan were set to expire on

November 9, 2018; the conditional registration for Engenia was set to expire on

December 20, 2018. The EPA wrote that the conditional registrations would

2

 The states are Alabama, Arizona, Arkansas, Colorado, Delaware, Florida,

Georgia, Illinois, Iowa, Indiana, Kansas, Kentucky, Louisiana, Maryland,

Michigan, Minnesota, Mississippi, Missouri, Nebraska, New Jersey, New Mexico,

New York, North Carolina, North Dakota, Ohio, Oklahoma, Pennsylvania, South

Carolina, South Dakota, Tennessee, Texas, Virginia, West Virginia, and

Wisconsin.

10
automatically expire unless the agency determined that off-site incidents of

dicamba damage were not occurring at “unacceptable frequencies or levels.”

The EPA’s 2016 registration decision required a detailed label restricting the

manner in which the dicamba-based herbicides could be used. The most important

restrictions were: (1) application was prohibited during wind speeds above fifteen

miles per hour; (2) application was prohibited during temperature inversions; (3)

application was prohibited if rain was expected in the next twenty-four hours; (4)

application was prohibited when spraying equipment was traveling at a ground

speed above fifteen miles per hour; (5) a buffer of at least 110 feet between the last

treated crop row and the nearest downwind edge of the field was required; and (6)

a maximum sprayer boom height of twenty-four inches above the weeds or crop

canopy was required.

C. Experience During the 2017 Growing Season, and

 Label Amendment for the 2018 Growing Season

XtendiMax, Engenia, and FeXapan were on the market in time for the 2017

growing season. Many farmers adopted the new crop system, planting seeds with

Monsanto’s dicamba-tolerance trait on 27 million acres and using dicamba

herbicides on the post-emergent crops. From 2012 to 2016, before use of OTT

dicamba was allowed on DT soybeans and cotton, an average of 231,000 pounds

acid equivalent of dicamba had been applied each year to cotton, while an average

11
of 537,000 pounds of dicamba had been applied to soybeans. In 2017, almost 8

million pounds of dicamba were applied to post-emergent soybeans, and almost 2

million pounds were applied to post-emergent cotton.

In its 2016 registration decision, the EPA had written that the label

restrictions were “expected to eliminate any offsite exposures” to dicamba. 

(Emphasis added.) But as the 2017 growing season progressed, complaints of

dicamba-caused damage to commercial crops and other plants soared. By the end

of the season, according to a report by Professor Kevin Bradley of the University

of Missouri, 2,708 formal complaints of dicamba-caused damage were being

investigated by state departments of agriculture. Bradley reported that university

weed scientists estimated that approximately 3.6 million acres of soybeans in

twenty-four states, or about 4 percent of all U.S. soybean acreage, were damaged

by off-field movement of dicamba. 

Reuben Baris, Acting Chief of the herbicide branch of the EPA’s Office of

Pesticide Programs, told state regulatory officials at a meeting in Washington,

D.C., in the fall of 2017 that the agency was “very concerned with what has

occurred” with the OTT use of dicamba. During a presentation in September 2018,

Baris confirmed that “[m]ore than 3.6 million acres” of soybeans had been

damaged by dicamba during the 2017 season. Baris noted, further, that the

reported damage was likely an underestimate of the actual damage because, in his

12
words, “[n]ot all reports of crop damage were reported to State Departments of

Agriculture.” Speaking on the topic of dicamba at an annual meeting of the

Pesticide Stewardship Alliance in February 2018, Rick Keigwin, the Director of

the EPA’s Office of Pesticide Programs, remarked, “I don’t say this in jest, but

2018 cannot look like 2017.”

Monsanto proposed changes to the XtendiMax label for the 2018 growing

season to address what the EPA characterized as a “high number of crop damage

incidents.” The EPA also consulted state agencies and the U.S. Department of

Agriculture on the changes, but it did not undertake a formal registration

amendment process before approving additional label restrictions for the OTT

dicamba products for the 2018 season. The most important additional restrictions

were: (1) application was prohibited if the wind speed during application was less

than three miles per hour or more than ten miles per hour (rather than more than

fifteen miles per hour); (2) application was permitted only between sunrise and

sunset (rather than at any time other than during a temperature inversion); (3) the

herbicides had to be labeled as “restricted use pesticides,” which could be applied

only by certified applicators or people working under their direct supervision; and

(4) applicators had to receive dicamba-specific training. 

In a letter to Monsanto adopting the changes, the EPA wrote, “The

amendment approved through this letter includes additional restrictions further

13
minimizing off-field movement of the active ingredient dicamba and do not affect

the conclusions in the supporting assessment of risk. EPA accordingly continues

to rely on all the assessments that supported the new uses, and therefore does not

require . . . [any] new risk assessment.” In other words, the EPA continued to rely

on its risk assessment from a year earlier, when it had concluded that the 2016

labeling requirements “are expected to eliminate any offsite exposures and

effectively prevent risk potential to people and non-target species.”

D. Experience During the 2018 Growing Season

In 2018, more than 103 million acres of soybeans and cotton were planted in

the United States. Of that total, 56 million acres were planted with seeds with

Monsanto’s dicamba-tolerance trait, up from 27 million acres the year before. 

Bradley reported that by July 15, 2018, university weed scientists estimated that in

eighteen states there were about 1.1 million acres of soybeans with dicamba

damage. The other sixteen states where OTT dicamba was approved were not

included in the report. By the same date the previous year, Bradley reported,

university weed scientists had estimated 2.5 million acres of damaged soybeans. It

is unclear how many states were included in the July 2017 estimate.

The 2018 growing season was again marked by many complaints of off-site

dicamba damage. In the country’s major soybean-producing states, the sharp

increase in 2017 of complaints to state agriculture departments about dicamba

14
damage to crops was followed by only a slight decrease in complaints in 2018. In

2017 and 2018, Illinois, Indiana, Iowa, Minnesota, Missouri, Nebraska, North

Dakota, and South Dakota planted the most acres of soybeans. See Quick Stats,

NAT’L AGRIC. STATISTICS SERV.,

https://quickstats.nass.usda.gov/results/96B2EF56-2AC3-329E-803E6D6D3CC5444C. In those states in 2017, there were 1,287 complaints to state

departments of agriculture of dicamba damage; in 2018, there were 1,064

complaints. In total, according to the Association of American Pesticide Control

Officials, approximately 1,400 complaints of crop damage resulting from OTT

dicamba herbicides were reported to state regulatory authorities in 2018. 

There were substantial differences from state to state in reported dicamba

damage in 2018. Some states imposed restrictions for the 2018 growing season

over and above the label requirements imposed by the EPA and experienced

substantial decreases in the number of dicamba complaints. For example, in 2018

Minnesota imposed two additional restrictions on OTT application of dicamba

herbicides: (1) after June 20, OTT application of dicamba was forbidden; and (2)

before June 20, OTT application of dicamba was forbidden on days when field

temperatures exceeded 85 degrees. In 2017, there were 250 complaints of

dicamba-related crop damage in Minnesota; in 2018, there were 29. Similarly, in

2018 Arkansas prohibited OTT applications of dicamba between April 16 and

15
October 31, effectively banning its use during the growing season. In 2017, there

were 986 complaints of dicamba-related crop damage in Arkansas; in 2018, there

were 200. By contrast, in 2018 Illinois imposed no additional requirements

beyond those on the EPA label. In 2017, there were 245 complaints of dicambarelated crop damage in Illinois; in 2018, the number of complaints increased to

330.

E. 2018 Registration Decision

With the 2016 conditional registrations due to expire in late 2018, Bayer

(Monsanto’s new owner), Corteva, and BASF sought amendments that would

extend the registrations for another two years. On October 31, 2018, the EPA

announced it would “be granting requests by Bayer CropScience (formerly

Monsanto Company), Corteva (formerly DuPont), and BASF to amend their

existing conditional registrations that contain expiration dates of November 9,

2018, and December 20, 2018, respectively.” On November 1, 2018, pursuant to

its October 31 “registration decision,” the EPA issued a conditional registration to

Bayer for its “M1768 Herbicide,” also known as XtendiMax. On November 2,

2018, the EPA issued a conditional registration to BASF for its “Engenia

Herbicide.” On November 5, 2018, the EPA issued a conditional registration to

Corteva for its “DuPont FeXapan Herbicide.”

16
In its October 31, 2018, decision to grant the conditional registrations, the

EPA assessed the benefits and costs of OTT application of dicamba on DT

soybeans and cotton. In making this assessment, the EPA had before it comments

from state agencies, farm bureaus, trade associations, farmers, seed companies,

crop consultants, non-governmental organizations, academic and commercial weed

scientists, and various other individuals. 

The EPA found two benefits resulting from OTT application of dicamba. 

First, dicamba “provides growers with an additional postemergence active

ingredient to manage difficult to control broadleaf weeds during the crop growing

season, particularly for those situations where herbicide-resistant biotypes, such as

Palmer amaranth, may occur (and few alternatives are available).” Second,

dicamba “provides a long-term benefit as a tool to delay resistance [to] other

herbicides when used as part of a season-long weed management program that

includes preemergence (residual) and postemergence (foliar) herbicides (along

with rotations between different MOA [modes of action]).” 

In a separate document prepared by the EPA Office of Pesticide Programs

(“OPP document”) and dated the same day as the registration decision document,

the EPA rejected two additional benefits that had been proposed by the registrants. 

First, the EPA refused to find that OTT application of dicamba to DT soybean and

cotton provided a comparative advantage in increasing crop yields: “The Agency

17
finds that dicamba can control weeds that might lead to yield loss but did not find

sufficient information to show it was more effective than other weed control

programs in reducing yield loss due to weeds.” Second, the EPA refused to find

that OTT dicamba was “a crucial part of maintaining a conservation tillage

program.”

In its October 31 decision document, the EPA also listed the costs, or risks,

of dicamba use, which it characterized as “impacts.” It first discussed in a single

paragraph “[i]mpacts to non-dicamba tolerant soybean growers.” Citing a

slideshow from Monsanto’s second quarter 2018 financial results, the EPA wrote

that Monsanto had predicted that 40 million acres of DT soybeans would be

planted in 2018. The EPA then inferred that 55 percent of the 2018 soybean crop

would be non-DT and “may potentially be damaged by very low levels of offtarget dicamba.” In the OPP document, the EPA elaborated that “[i]n general,

exposure during the reproductive growth stages could result in reductions in

yield . . . , but the Agency does not have information to quantify this claim.”

The EPA next mentioned in a single paragraph “[i]mpacts to growers of

other dicamba sensitive crops.” It wrote, “Many other plants are sensitive to low

levels of dicamba and are listed on the dicamba labels.” The EPA named a number

of the dicamba-sensitive crops listed on the labels. It also noted that the labels list

“about 250 weeds—annual and perennial broadleaf plants and trees— . . . some of

18
which are desirable in non-crop settings.” In its separate OPP document, the EPA

wrote that “[t]he Agency does not know the extent of the damage to sensitive

crops.” 

Finally, the EPA noted in a single paragraph “[i]mpacts to the landscape.” 

It wrote, “In 2017 and 2018, state agencies received reports from growers about

incidents alleging damage to trees and other non-crop plants . . . . Potential impacts

could result in damage to shelterbelts and windbreaks, as well as desirable plants in

public parks and spaces.”

In its decision authorizing additional two-year conditional registrations, the

EPA imposed more restrictions on OTT application of dicamba herbicides to DT

soybeans and cotton. The most important additional restrictions were: (1)

application was permitted only between one hour after sunrise and two hours

before sunset (rather than any time between sunrise and sunset); (2) only two OTT

applications were permitted per crop for soybeans, with the last application made

no later than forty-five days after planting; (3) only two OTT applications were

permitted per crop for cotton, with the last application made no later than sixty

days after planting; (4) an omnidirectional, in-field fifty-seven-foot buffer was

required in certain counties to protect listed plant species; and (5) applications

could be made only by certified applicators.

II. Procedural History

19
Petitioners previously filed a petition for review of the EPA’s 2016

registration decision for XtendiMax. Monsanto filed a motion to intervene, which

we granted. Following the October 2017 label amendments, petitioners filed a

motion to amend their petition for review, which we also granted. We held oral

argument on August 29, 2018. 

The EPA’s October 31, 2018, decision to grant additional, conditional twoyear registrations for XtendiMax, Engenia, and FeXapan was published before we

issued an opinion. We therefore held petitioners’ challenge moot, as the 2016

registration decision no longer had any legal effect. We held that petitioners’

challenge was not “capable of repetition but evading review” because there was no

reasonable expectation that petitioners would be subject to the same action—the

2016 registration decision—again. See Pub. Utils. Comm’n v. FERC, 100 F.3d

1451, 1459–60 (9th Cir. 1996). We therefore dismissed the petition.

Petitioners filed a new petition for review on January 11, 2019, challenging

the EPA’s October 31, 2018, decision. Monsanto again filed a motion to

intervene, which we granted. We directed the Clerk of the Court to set an

expedited briefing schedule. We held oral argument on April 21, 2020.

III. Jurisdiction

20
FIFRA provides for review in the courts of appeals “as to the validity of any

order issued by the Administrator following a public hearing” by “any person who

will be adversely affected by such order and who had been a party to the

proceedings.” 7 U.S.C. § 136n(b). A petition for review must be filed within sixty

days of the entry of a challenged order. Id. “Unless the Administrator otherwise

explicitly provides in a particular order, . . . the . . . date of entry of an order issued

by the Administrator following a public hearing . . . shall be . . . on the date that is

two weeks after it is signed.” 40 C.F.R. § 23.6.

The Administrator signed the EPA’s decision document on October 31,

2018. Petitioners filed their petition for review within two weeks and sixty days of

that date, on January 11, 2019. Intervenor Monsanto argues that we lack

jurisdiction, contending that the petition was filed too late. The EPA does not join

Monsanto’s argument. 

Monsanto contends that because the XtendiMax registration was “issued”

and its Master Label marked “accepted” on November 1, 2018, that date

constitutes the “date of entry,” making the EPA’s decision immediately reviewable

and the petition therefore untimely. We disagree. Neither the November 1

registration nor the November 1 Master Label acceptance “explicitly provides” that

the “date of entry” of the EPA’s order has been altered. We therefore conclude

that the petition for review was timely filed and that we have jurisdiction. 

21
IV. Scope of Petitioners’ Challenge

Petitioners challenge the EPA’s October 31, 2018, decision to conditionally

amend the registrations of XtendiMax, Engenia, and FeXapan, permitting the OTT

use of dicamba on DT soybeans and cotton for another two years. The scope of

petitioners’ challenge is stated in the first sentence of their brief: “This petition

seeks review of the October 31, 2018 decision by the United States Environmental

Protection Agency (EPA) to continue the new uses registrations of the pesticide

dicamba on dicamba-resistant cotton and soybean[.]”

The EPA, however, asserts that petitioners have challenged only the

registration of XtendiMax. It writes in its brief in a footnote: “Although not at

issue here, EPA has issued registrations for two other dicamba products for the

same uses, Engenia and FeXapan. . . . EPA’s 2018 registration action also

amended the Engenia and FeXapan registrations.” The EPA made no argument in

its brief in support of its contention that only the registration of XtendiMax is at

issue. We could have held that the EPA’s failure to make an argument in support

of its assertion waived the argument. See Aramark Facility Servs. v. Serv. Emps.

Int’l Union, 530 F.3d 817, 824 n.2 (9th Cir. 2008) (holding that arguments made in

passing and inadequately briefed are waived). However, out of an abundance of

caution and in recognition of the significant practical importance of the question,

we asked for supplemental briefing from the parties and intervenor Monsanto.

22
In their petition for review, filed January 11, 2019, petitioners challenged an

“order . . . announced in a document signed on October 31, 2018.” They attached

as their sole exhibit the EPA’s October 31 decision, which they argued was

“intertwined with and extended two earlier registration decisions by EPA over this

same pesticide product,” referring to the EPA’s 2016 registration decision and the

2017 label amendment decision. Their opening brief before this court is consistent

with their petition.

The EPA’s October 31, 2018, decision to register the three dicamba

herbicides for OTT application qualifies as an “order” issued by the EPA. See 7

U.S.C. § 136n(b); Pollinator Stewardship Council v. EPA, 806 F.3d 520, 528 (9th

Cir. 2015) (reviewing “the EPA’s decision to . . . register” a new insecticide)

(emphasis added); cf. 7 U.S.C. § 136n(a) (conferring jurisdiction in the district

court for “final actions of the Administrator not committed to the discretion of the

Administrator by law”). For our court to have jurisdiction, the EPA’s decision

must also follow a “public hearing.” 7 U.S.C. § 136n(b). We conclude that the

2018 registration decision was issued by the EPA “following a public hearing,” as

the decision arises from a notice-and-comment period held prior to the related 2016

registration decision. We have construed the term “public hearing” broadly,

holding that it merely “identifies elements essential in any fair

proceeding—notice . . . given of a decision to be made and presentation to the

23
decisionmaker of the positions of those to be affected by the decision. By itself,

the term does not connote more.” United Farm Workers of Am. v. EPA, 592 F.3d

1080, 1082 (9th Cir. 2010). Accordingly, we have held that “a ‘hearing’ includes

proceedings in which there is no presentation of public argument.” Id. The EPA’s

previous 2016 registration decision followed a “public hearing,” as conceded by

the EPA and Monsanto.

The EPA and Monsanto make two unconvincing arguments for a restricted

scope of review. First, they both argue that the other two registrants—Corteva and

BASF—were not given fair notice of the petition, citing Federal Rule of Appellate

Procedure 15(a)(2)(C). They cite as support for their argument the fact that only

Monsanto has intervened. It is true that the Corteva and BASF have not

intervened. But that does not change the nature of petitioners’ challenge to the

EPA’s October 31, 2018, registration decision. As even Monsanto admitted in its

supplemental brief to us, while the “petition for review did not mention the

Engenia or FeXapan registration orders[,] [s]trictly speaking, it did not mention the

XtendiMax registration order either.”

Second, the EPA argues that petitioners’ challenge cannot include FeXapan

and Engenia because “[t]hese other registrations have administrative records that

may overlap with, but are distinct from the administrative record for XtendiMax.” 

However, the administrative record produced by the EPA includes materials

24
concerning all three products. Comments in the record pertain to all three

herbicides, with the EPA listing “general comments” in favor of and in opposition

to “OTT registrations of dicamba.” Most important, the registration decision,

including its risk assessments and cost-benefit analysis, concerned OTT dicamba

products generally and was not registrant-specific. Indeed, the EPA’s decision

document specifies that “[t]hree registrations . . . are impacted by this decision.”

Petitioners directly challenged the EPA’s entire October 31, 2018,

registration decision. The EPA’s subsequent registrations of the three herbicides

followed within days of its October 31 decision and were premised on that

decision. We conclude that all three registrations are at issue in the petition before

us. 

V. Standard of Review

We will sustain the EPA’s 2018 registration decision under FIFRA “if it is

supported by substantial evidence when considered on the record as a whole.” 7

U.S.C. § 136n(b). The substantial evidence standard requires that we “affirm the

EPA’s finding where there is such relevant evidence as a reasonable mind might

accept as adequate to support a conclusion even if it is possible to draw two

inconsistent conclusions from the evidence.” Nat. Res. Def. Council v. EPA, 857

F.3d 1030, 1036 (9th Cir. 2017) (internal quotation marks omitted). We “give due

deference to EPA’s findings,” but may uphold its decision only “on the basis

25
articulated by the agency itself.” Nat. Res. Def. Council v. EPA, 735 F.3d 873, 877

(9th Cir. 2013). 

VI. Discussion 

FIFRA regulates pesticide (including herbicide) use, sales, and labeling. 7

U.S.C. §§ 136–136y. The statute is administered by the EPA, with states given

primary enforcement responsibility for pesticide use violations. Id. §§ 136a(a),

136w–1; see Taylor AG Indus. v. Pure-Gro, 54 F.3d 555, 559 (9th Cir. 1995). 

“FIFRA uses a cost-benefit analysis to ensure that there is no unreasonable risk

created for people or the environment from a pesticide.” Pollinator Stewardship

Council, 806 F.3d at 522–23 (internal quotation marks omitted).

The EPA wrote in its October 31, 2018, decision that it was taking action

under Section 3(c)(7)(B) of FIFRA when it approved the registrations for

XtendiMax, Engenia, and FeXapan. See 7 U.S.C. § 136a(c)(7)(B). That section

authorizes the Administrator of the EPA to “conditionally amend” the registration

of a pesticide to allow for new uses. Id. Section 136a(c)(7)(B) provides in

relevant part:

The Administrator may conditionally amend the registration of a

pesticide to permit additional uses of such pesticide notwithstanding

that data concerning the pesticide may be insufficient to support an

unconditional amendment, if the Administrator determines that (i) the

applicant has submitted satisfactory data pertaining to the proposed

additional use, and (ii) amending the registration in the manner

26
proposed by the applicant would not significantly increase the risk of

any unreasonable adverse effect on the environment.

An “unreasonable adverse effect on the environment” includes “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.” Id. § 136(bb).

We consider in turn the two requirements for conditional amendments under

§ 136a(c)(7)(B): determinations that (i) the applicant has submitted “satisfactory

data,” and (ii) the amendment will not “significantly increase the risk of any

unreasonable adverse effect on the environment.” We conclude that substantial

evidence does not support the EPA’s conclusion that both statutory prerequisites

were satisfied. 

A. “Satisfactory Data” Submitted by the Applicant 

We begin by considering whether substantial evidence supported the EPA’s

conclusion that the “applicant has submitted satisfactory data pertaining to the

proposed” conditional registrations. The EPA suggests that these “data” include

registrant-submitted studies, the broader universe of academic studies and datasets,

and incident reports. We accept for present purposes the EPA’s interpretation of

the term “data.”

1. Monsanto’s Studies

27
In support of its 2018 application, Monsanto submitted the results of several

of its own field studies evaluating XtendiMax. Some of the studies had been

submitted in support of Monsanto’s application for conditional registration in

2016. Some of the studies were new. All of the studies were described in a “white

paper” Monsanto submitted to the EPA in support of its 2018 application.

a. Field Studies in Support of the 2016 Registration

Monsanto conducted its own studies of its reformulated dicamba herbicide

prior to its application for conditional registration in 2016. Monsanto did not at

that time make its herbicide available for independent studies. On a 3.4-acre field

in Georgia and a 9.6-acre field in Texas, Monsanto tested XtendiMax (with

“VaporGrip Technology”) as well as M-1691, a dicamba-based formulation less

volatile than older dicamba herbicides but lacking “VaporGrip Technology.” In its

2018 white paper, Monsanto described these studies as having “tested real-world

volatility potential” of XtendiMax. Based in part on results of these tests, as

reported by Monsanto, the EPA granted the first two-year conditional registration

for OTT dicamba, concluding that the benefits of its application to DT soybeans

and cotton outweighed any risks because the label restrictions were “expected to

eliminate any offsite exposures and effectively prevent risk potential to people and

non-target species.” As described above, and as the EPA later acknowledged, the

EPA’s conclusion was incorrect.

28
b. Field Studies in Support of the 2018 Registration

In support of its 2018 application, Monsanto conducted five additional

studies measuring the volatility of XtendiMax. In its white paper, Monsanto

described these studies as “confirm[ing] information provided prior to 2016.” The

“information provided prior to 2016” included, of course, the studies submitted by

Monsanto in support of its 2016 application. Relying in part on those studies, the

EPA had mistakenly concluded that OTT application of XtendiMax created

“minimal risks, if they exist at all.” Monsanto further described the new studies as

“mimic[king] many ‘real world’ commercial applications and captur[ing] the full

range of potential conditions that might cause volatility.”

The first additional study was conducted in October 2016 in Texas on a bare

4.6-acre field, and a post-emergent 9.1-acre DT cotton field. The second study was

conducted in December 2017 on a post-emergent thirty-seven-acre soybean field in

Australia. The third study was conducted in May 2018 on a post-emergent twentysix-acre soybean field in Arizona. The fourth study was conducted in May and

June 2018 on a post-emergent, nine-acre DT soybean field in Missouri. The fifth

study was conducted in June and July 2018 on a post-emergent one-hundred-acre

soybean field in Nebraska. All five studies measured air samples to determine the

flux rate of volatilized dicamba. (Flux rate is a measurement of volatilized

dicamba during a specific time period.) In its white paper, Monsanto described

29
each of the five studies as concluding that “[t]he highest peak flux rate [was] . . .

consistent with peak flux values from the Texas and Georgia studies submitted

prior to the 2016 XtendiMax registration.”

Monsanto also conducted a spray drift study in conjunction with its volatility

study on the Arizona soybean field. It reported the result of its study as “consistent

with and confirmatory of . . . EPA’s 2016 determination that no spray drift would

occur outside of the 110-ft. buffer area in amounts that could have an effect on

plant height.”

2. Telephone Reports to Monsanto

Monsanto reported in its white paper that it had received “hundreds of

telephone calls regarding alleged off target movement” of dicamba during the 2017

and 2018 growing seasons. Monsanto reported that by July 19, 2017, it had

received 1,002 calls. Monsanto reported that as of the same date on 2018 it had

received 468 calls. Of the 468 calls in 2018, herbicide applicators had made 172

calls, and “non-applicators” had made 296. Monsanto reported that it had

evaluated 450 of the calls. Monsanto concluded that XtendiMax was never, or

almost never, at fault. It wrote, “XtendiMax volatility caused few if any incidents

of off-target movement. Indeed, Monsanto has identified only eight incidents (less

than 1%) where volatility even possibly could have been the cause—and none of

30
those were confirmed to be caused by volatility as all eight incidents had other

potential causes as well.” (Emphasis in original.)

Monsanto absolved XtendiMax based primarily on the fact that many of the

fields with alleged dicamba damage were located fifty to one hundred feet away

from corn fields. Monsanto speculated that other herbicides, such as older

formulations of dicamba, had been used on the corn fields and had drifted onto

adjacent non-DT soybean fields. This explanation, however, is not supported by

the data.

Older, non-XtendiMax dicamba has been used on post-emergent corn fields

for decades, and complaints of dicamba damage to adjacent crops had been

consistently low. Monsanto needed to explain why, if herbicide use on corn fields

was at fault, the number of herbicide drift complaints had skyrocketed in 2017 and

2018, after XtendiMax, Engenia, and FeXapan were registered for post-emergent

use. Monsanto theorized, without supporting evidence, that because of the

increased publicity surrounding the new dicamba formulations, the applicators and

farmers who complained of dicamba damage were “noticing—and reporting for the

first time—effects that likely have been present for years.” There is no indication

in the white paper that Monsanto ever sought to confirm its theory by asking

growers on the adjacent corn fields whether, when, and in what manner, they might

have used dicamba. Moreover, a 2014 U.S. Department of Agriculture report

31
indicates that use of the older formulations of dicamba on corn had been falling in

recent years, as corn growers turned to newer herbicides. Between 1993 and 1997,

dicamba had been used on between 21 and 29 percent of corn acreage; in 2012, it

was used on only about 12 percent of corn acreage. 

3. Other Field Studies

In making its 2018 registration decision, the EPA also considered data from

research conducted by the University of Arkansas, the University of WisconsinMadison, Purdue University, Michigan State University, and the University of

Nebraska. These studies were designed to evaluate spray drift and volatility of

dicamba when applied to fields of ten to forty acres. The EPA also looked at a

series of small-scale field studies (0.17 to 3.5 acres) conducted in Arkansas,

Indiana, Missouri, Nebraska, and Tennessee. Studies in both the larger-scale and

small-scale settings assessed both Engenia and XtendiMax. (XtendiMax and

FeXapan involve the same form of dicamba and both have “VaporGrip

Technology.”) From the field data, the EPA concluded that even the newer

dicamba formulations could volatilize and drift, resulting in visual injury to plants.

4. Summary

The applicant data before the EPA ahead of the 2018 conditional

registrations consisted in part of studies that Monsanto characterizes as merely

confirming data used to support the 2016 registrations. The 2016 registrations, of

32
course, resulted in millions of acres of reported dicamba damage. But we need not

decide whether substantial evidence supports the EPA’s conclusion that

“satisfactory data” had been submitted. See 7 U.S.C. § 136a(c)(7)(B)(i) (requiring

that the “applicant . . . submit[] satisfactory data pertaining to the proposed

additional use”). FIFRA requires both “satisfactory data” and a finding that

amendment of the registration will not “significantly increase the risk of any

unreasonable adverse effect on the environment.” Id. § 136a(c)(7)(B)(i)–(ii). We

turn now to this second requirement and conclude that the EPA’s determination

that the requirement was satisfied is not supported by substantial evidence.

B. Whether Amendment “Significantly Increase[s] the Risk of Any

Unreasonable Adverse Effect on the Environment”

To approve a conditional amendment of a registration for an already

registered pesticide, the Administrator of the EPA must find under FIFRA that the

amendment “would not significantly increase the risk of any unreasonable adverse

effect on the environment.” Id. Such effects include “any unreasonable risk to

man or the environment, taking into account the economic, social, and

environmental costs and benefits of the use any pesticide.” Id. § 136(bb). In its

October 31, 2018, decision document, the EPA concluded “that extending the OTT

use of dicamba for two years on dicamba-tolerant cotton and dicamba-tolerant

33
soybeans in the manner authorized under this decision will not cause unreasonable

adverse effects on the environment.”

As described above, the EPA found two benefits resulting from the 2018

registrations—providing soybean and cotton growers an additional tool for

managing difficult-to-control weeds, and delaying weed resistance to other

herbicides. Ample evidence supports these two findings. Notably, however, the

EPA in 2018 refused to find as a benefit that OTT application of dicamba

herbicides increased crop yields by comparison to application of other herbicides.

Against those two benefits, the EPA balanced the risks, which it

characterized as “impacts.” It divided those impacts into three categories—impacts

to non-DT soybean growers; impacts to growers of other dicamba-sensitive crops;

and impacts to the “landscape.”

A review of the record shows that the EPA substantially understated the

risks that it acknowledged. The review also shows that the EPA entirely failed to

acknowledge other risks. 

1. Understatement of Acknowledged Risks

In both the registration decision document signed on October 31 and the

OPP document dated the same day, the EPA substantially understated the risks to

non-DT plants by OTT application of dicamba herbicides.

a. DT Seed Acreage

34
First, the EPA understated the DT seed acreage that had been planted in

2018, and therefore the amount of dicamba herbicide that had been applied to postemergent crops that year. The EPA relied on a Monsanto prediction that 40

million acres of its DT soybeans would be planted in 2018. This reliance was

improper. The EPA’s decision document was signed on October 31, at the end of

the growing season. By then, the EPA was in a position to know the actual acreage

of DT seeds that had been planted. In its white paper, Monsanto had written that

56 million acres of its DT seeds had been planted in 2018. It did not specify what

share came from DT soybeans and what share came from DT cotton. But the

record elsewhere indicated that DT soybeans comprised as many as 50 million of

those acres. In other words, the EPA underestimated by as much as 25 percent the

amount of DT soybeans planted and, commensurately, the amount of dicamba

herbicides applied in 2018. 

b. Under-Reporting or Over-Reporting of Dicamba Damage

Second, the EPA’s conclusion that complaints to state departments of

agriculture of dicamba damage could have either under-reported or over-reported

the actual amount of damage is not supported by substantial evidence. The record

clearly shows that complaints understated the amount of dicamba damage.

35
A graph included in the EPA’s decision document shows complaints made

to state agriculture departments in sixteen of the thirty-four states in which OTT

application of dicamba was authorized. The graph covers the period from 2013

through 2018 and includes all complaints of herbicide drift, not limited to dicamba. 

According to the graph, herbicide drift complaints consistently averaged slightly

fewer than 1,000 per year from 2013 through 2015. The number of complaints

rose to a little under 1,250 during 2016—the year DT soybeans and cotton became

available for planting and were reportedly sprayed with dicamba herbicides not

approved for OTT use. In 2017, the first year that OTT application of dicamba

was allowed, there were more than 3,000 drift complaints. In 2018, there were

more than 2,250 such complaints. 

The EPA has no explanation for the spike in complaints in 2017 and 2018

other than the new conditional registration of dicamba for OTT application. The

EPA minimized the significance of the increase in complaints by crediting a view

that the number of complaints could reflect an over-reporting of damage. It wrote

in its registration decision that many industry stakeholders believed that the

number of complaints under-reported the amount of dicamba-caused damage, but

that “others” believed instead that the complaints over-reported the amount of

damage: 

36
According to the AAPCO [the Association of American Pesticide

Control Officials], university researchers, and some growers, the

number of cases reported to state agencies may be substantially lower

than the actual incidents . . . observed in the field . . . . Others believe

that there may be issues of overreporting.

(Emphasis added.) The EPA wrote to the same effect in its OPP document, “The

number of incidents may not accurately represent the extent of dicamba-related

damage; incidents may be under- or over-reported.”

The EPA did not specify in the text of its registration decision who the

“others” (plural) were. However, it appended to the text a footnote citing only the

Monsanto white paper. That is, Monsanto, and only Monsanto, was the “others.”

As noted above, Monsanto wrote in its white paper that it had concluded that none,

or almost none, of the damage reported in the 450 telephone calls it had evaluated

in 2018 had been caused by the newly registered dicamba herbicides. Monsanto

speculated that the damage was largely caused by other herbicides, including the

older formulations of dicamba, applied on nearby corn fields; speculated that the

professional applicators and farmers who called complaining of dicamba damage

had had such damage in prior years; and speculated that the callers either had not

noticed the damage previously or had not attributed it to dicamba. (Recall that

dicamba use on corn had been decreasing in recent years, and that dicamba damage

is easily detected by its signature “leaf cupping” on affected plants.)

37
The EPA’s purported agnosticism as to whether dicamba damage was underor over-reported is contradicted by overwhelming record evidence that dicamba

damage was substantially under-reported. For example, during the summer of

2018, Professor Robert Hartzler at Iowa State University (“ISU”) conducted a

survey of university field agronomists that was forwarded to Baris of the EPA. 

Hartzler recounted: “We know the reported incidences represent a very small

fraction of total drift cases as farmers are reluctant to involve regulatory agencies. 

The majority of ISU Extension and Outreach agronomists reported that Iowa

Department of Agriculture and Land Stewardship (IDALS) was contacted in less

than 25% of the dicamba cases, and nobody reported IDALS was contacted in the

majority of cases.” In a September 2017 article in the record from the Progressive

Farmer, Carrie Leach, Quality Assurance Director for the Office of Indiana State

Chemist, estimated that only one out of ten farmers affected by dicamba injury

actually filed formal complaints with her office. In September 2018, before the

EPA issued its decision document, Baris himself gave a PowerPoint presentation in

which he admitted, “Not all reports of crop damage were reported to State

Departments of Agriculture.” If complaints to state departments of agriculture

under-reported dicamba damage, the amount of actual dicamba damage was, of

course, even greater than what the graph in the EPA’s 2018 decision document

captured.

38
c. Failure to Quantify or Estimate Dicamba Damage

Third, the EPA refused to quantify or estimate the amount of damage caused

by OTT application of dicamba herbicides, or even to admit that there was any

damage at all. When referring to dicamba damage to non-DT soybeans, the EPA

wrote in its 2018 decision document only that such soybeans “may potentially be

damaged.” (Emphasis added.) In the accompanying OPP document, it wrote with

respect to such soybeans, “In general, exposure during the reproductive growth

stages could result in reductions in yield . . . , but the Agency does not have

information to quantify this claim.” (Emphasis added.) When referring to other

non-DT crops, the EPA identified a number of such crops by name, but did not

write that any had been damaged by dicamba. When referring to dicamba-caused

damage to the “landscape,” it wrote only of “incidents alleging damage” and of

“[p]otential impacts [that] could result in damage.” (Emphasis added.)

The EPA had information from which it could have quantified dicamba

damage, even if it could not have calculated with precision the reduction in yield

caused by the damage. For example, Baris had conceded in his September 2018

PowerPoint presentation that in 2017 “more than 3.6 million” acres of non-DT

soybeans had been damaged by dicamba. Indeed, in its 2018 registration decision,

the EPA itself referred to the 3.6 million figure. Bradley of the University of

Missouri, the source of the 3.6 million figure, had reported that by mid-July 2018,

39
approximately 1.1 million acres of non-DT soybeans had already been damaged in

eighteen states. 

The EPA also had a great deal of qualitative information about extensive

dicamba damage during both 2017 and 2018. We focus here only on the damage

reported in 2018. In comments forwarded by email to Baris, Bradley wrote that as

of June 1, “university weed scientists and state Department of Agriculture

representatives” had reported dicamba injury to “specialty crops, vegetable, and

ornamental, fruit, and shade trees.” Dr. Ford Baldwin of Practical Weed

Consultants, LLC in Arkansas wrote in a letter forwarded to Baris on June 25,

“Once again in 2018, large acreages of non-dicamba-tolerant soybeans in eastern

Arkansas are affected by this herbicide as well as many vegetables. In addition,

most trees in the countryside and towns are cupping and even dying following

multiple years of exposure.” In a Farm Progress news article on June 26, Bradley

is quoted as saying, with respect to dicamba damage in the “bootheel” of Missouri,

“From what I can tell, . . . if you don’t have Xtend soybean, your crop is going to

be cupped from one end to the other. That’s not a surprise because we’ve seen that

for the past two seasons.”

In a July 2 email forwarded to Baris, Duane Simon, a Supervisor at the

Kansas Department of Agriculture, wrote, “So you know, for the last two weeks

we have been over run with dicamba complaints in Kansas. Most of them have

40
been on the Eastern side of the state.” Andrew Thostenson, a pesticide program

specialist at North Dakota State University, wrote in a July 23 email to Baris,

“What we now know, in 2018, is that minimizing off target movement of dicamba

to a reasonable level is NOT possible. If you take 2017[] off the board, and only

look at what has happened in 2018, I think this level of movement is completely

unacceptable.” A July 20 article in DTN’s Progressive Farmer, forwarded to an

EPA official on July 25, reported extensive dicamba damage. Damage suffered by

Mike Hayes, a Tennessee resort owner, was one of many examples: “Last year,

Hayes experienced wave after wave of dicamba exposure. It wiped out the resort’s

garden—which supplies the on-site restaurant—three times before Hayes gave up. 

He estimates it killed 20% of the young trees he planted . . . . This year, he

estimates he has been hit eight separate times by dicamba. He expects five cypress

trees to die this year . . . .”

In an August 8 article in Delta Farm Press, Professor Larry Steckel of the

University of Tennessee wrote, “[T]he drift we . . . saw this June and July in

Tennessee with dicamba in the new use pattern in Xtend crops is like nothing I

have ever seen before. I have never seen a herbicide that has so easily and

frequently slipped the leash. Nor have I seen a herbicide that, once off the leash,

would roam so far. Dicamba drift for the past three years has often travelled a half

mile to three-quarters of a mile and, all too frequently, well beyond that. . . . My

41
best estimate is that Tennessee has roughly 100,000 acres of non-dicamba tolerant

soybeans planted and about 40 percent of them are currently showing dicamba

injury.” Hartzler of ISU wrote in August 15 of his survey of ISU field

agronomists: “Half of the agronomists stated the number of soybean acres

damaged by dicamba was similar to 2017, whereas the remainder were split

between fewer acres and more acres damaged in 2018 than 2017. When I’ve asked

commercial agronomists the same question, the range of responses was similar to

those of my extension colleagues.” 

2. Failure to Acknowledge Risks

The EPA not only substantially understated the risks it acknowledged, as

just described. It also entirely failed to acknowledge other risks, including those it

was statutorily required to consider, as we describe below.

a. Substantial Non-Compliance with Label Restrictions

Extensive evidence in the record indicates that there is a risk of substantial

non-compliance with the EPA-mandated label for the 2019 and 2020 growing

seasons. Non-compliance with the restrictions, of course, will result in dicamba

damage. The EPA entirely failed to acknowledge this risk.

 As detailed above, there have been three sets of EPA-mandated label

restrictions for OTT use of XtendiMax, Engenia, and FeXapan. The initial set was

for the 2017 growing season, after the herbicides were first conditionally

42
registered; the second was for the 2018 growing season, after the herbicide

manufacturers “volunteered” to amend the label; and the third was for the 2019 and

2020 growing seasons, after the conditional registrations were extended for two

years. The labels became increasingly restrictive and, correspondingly, more

difficult to follow.

The 2018 label, for use during the 2019 and 2020 growing seasons, is hardly

a “label” as that term is usually understood. It is forty pages long, with myriad

instructions and restrictions. The 2018 label provides, inter alia, (1) application is

permitted only between one hour after sunrise and two hours before sunset; (2)

application is prohibited if the wind speed is below three miles per hour or above

ten miles per hour; (3) application is prohibited during temperature inversions; (4)

application is prohibited if rain resulting in soil runoff is expected in the following

twenty-four hours; (5) application is prohibited when the wind is blowing toward

“adjacent” non-DT soybean and cotton, as well as other dicamba-sensitive crops;

(6) there must be an in-field, downwind buffer of at least 110 feet; (7) in certain

counties, there must be an omnidirectional fifty-seven-foot in-field buffer; (8)

spraying equipment may not exceed a ground speed of fifteen miles per hour; (9)

the spray boom can be no more than twenty-four inches above the target weed or

the crop canopy; (10) for DT soybeans, only two applications per crop are

permitted, with the last application no later than forty-five days after planting; (11)

43
for DT cotton, only two applications per crop are permitted, with the last

application no later than sixty days after planting; and (12) all applicators must be

certified and have dicamba-specific training.

Even before the additional restrictions were added to the 2018 label, many

industry professionals had been dismayed by the difficulty in complying with the

complex and onerous label requirements. By October 2018, there was substantial

evidence that even conscientious applicators had not been able consistently to

adhere to the label requirements. 

Dave Coppess, an executive vice president at HeartLand Co-op in Iowa, was

interviewed for an April 17, 2018, article in Agribusiness Global. The article

appeared in Baris’ Google Alert for “dicamba,” and otherwise would have been

accessible to him. Coppess said of the label that had been in place for the 2017

growing season, “This was probably the most complex label I had ever seen in my

40-year career . . . .” “Last year, our sales manager calculated that based on the

[2017] label, we only had 44 hours of application time that our rigs would have

been on label. That’s the old label. Now, the new label is going to be even more

restrictive . . . .”

A question submitted to Keigwin of the EPA in April 2018 by an attendee of

a dicamba webinar for the Agricultural Retailers Association asked, “There doesn’t

appear to be any way for an applicator to be 100% legal in their application. What

44
is an applicator to do in this no-win situation?” Brian Major, a grain producer in

Fulton County, Kentucky, wrote in an August 15, 2018, email to Keigwin,

describing a DT soybean field surrounded by non-DT crops: “[T]here is no legal

way to spray this field. You can’t apply dicamba with a wind speed of 0 MPH

(must be 3-10 MPH) and you can’t apply it when the wind is blowing towards a

sensitive crop. So there is really no way to use the products.” He continued: “We

here in west Kentucky are also seeing a lackadaisical approach from the Ky Dept

of Agriculture on enforcement of the label, the fines for label violation are viewed

among the violators ‘as the cost of doing business’ or ‘it’s cheaper to pay the fine

than lose yield by not spraying.’” An August 21, 2018, National Public Radio

interview with a vineyard owner, circulated as an attachment to an internal EPA

email, reported: “Longtime winemaker Bobby Cox says a 10-mph day in blustery

West Texas is basically a fairy tale. ‘You can’t do it,’ he says, laughing

uproariously. ‘Your fairy godmother has to pull out a wand, tap the pumpkin and

turn it into a carriage.’”

In a July 20, 2018, article in a Purdue University newsletter forwarded by

Baris to his EPA colleagues, Purdue Professor Bill Johnson and Weed Science

Program Specialist Joe Ikley calculated the difficulty in complying with the 2017

label during the 2018 growing season. They ignored the label’s prohibition on

application when rain is forecast in the next twenty-four hours, instead relying on

45
actual rainfall events. Taking into account the restrictions based on wind speed

and temperature inversions, they calculated for a location near Purdue’s Indiana

agriculture station that there were only forty-seven hours in the entire month of

June 2018 during which OTT application of dicamba would have been legal. 

There were only two days of the month in which application during an eight-hour

day would have been possible—eleven hours during one day, and eight hours

during another. The remaining hours were scattered throughout the rest of the

month: one hour (one day); two hours (one day); three hours (three days), five

hours (two days); six hours (one day). Johnson and Ikley concluded that the data

“reinforces the fact that we do not have very many hours in the real world where

we can be completely compliant with the restrictions on the new dicamba product

labels.” Based in part on this data, the Office of Indiana State Chemist observed

that “the 2017 and 2018 dicamba label directions have been extremely challenging

for a trained applicator to comply with completely.”

The Illinois Fertilizer and Chemical Association conducted a survey of its

members in July and August 2018. One question was: “As a commercial

applicator, do you feel that your operators were able to follow the dicamba product

label effectively this year?” Approximately 66 percent of the respondents

answered “yes”; approximately 28 percent answered “most of the time”; and

approximately 6 percent answered “no.” Comments appended to the survey results

46
included: “Conditions that allow for a technically legal application is very small”;

“Weather is never right. Too windy, too hot, to[o] humid—we can’t win”; “Very

light, shifting winds made it impossible to ‘always be right’ during the time when

we needed to spray”; and “I believe it is impossible to make an on-label application

as the label is written . . . .”

The comments, emails, and news articles received by the EPA were directed

to the labels in place for the 2017 and 2018 growing years—the period leading up

to the EPA’s 2018 registration decision challenged here. As described above, the

EPA added even more restrictions in October 2018. Two changes are particularly

noteworthy. First, during 2018, OTT application of dicamba to DT soybeans and

cotton was legal from sunrise to sundown. During 2019 and 2020, the application

period will be reduced by three hours every day, now running from one hour after

sunrise to two hours before sunset. Second, in 2018, there was no days-afterplanting prohibition. In 2019 and 2020, farmers will have to apply OTT dicamba

within sixty days of planting DT cotton, and within forty-five days of planting DT

soybeans. Many applicators found it difficult or impossible to comply with the

2017 label during the 2018 growing season. Compliance with the 2018 label

during the 2019 and 2020 growing seasons will be even more difficult. 

In its October 31, 2018, decision approving OTT use of dicamba on DT

soybeans and cotton, the EPA nowhere acknowledged the evidence in the record

47
showing there had been substantial difficulty in complying with the mitigation

requirements of earlier labels. Nor did it acknowledge the likelihood that the

additional mitigation requirements imposed by the 2018 label would increase the

degree of non-compliance. 

b. “Economic, Social, and Environmental Costs”

FIFRA requires the EPA to consider, as part of a cost-benefit analysis, “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.” 7 U.S.C.

§ 136(bb) (emphasis added). The EPA entirely failed to acknowledge risks of

economic and social costs. 

1. Economic Cost

The EPA entirely failed to acknowledge an economic cost that is virtually

certain to result from the conditional registrations of the dicamba herbicides for

OTT application. The EPA knew that Monsanto’s glyphosate-resistance trait, and

accompanying glyphosate herbicide, had achieved a near-monopoly. More than 90

percent of soybeans planted in 2008 were grown from patented glyphosate-tolerant

seeds. Patented dicamba-tolerant seeds and the three new dicamba herbicides

appear to be well on their way to the same degree of market dominance. By 2017,

soybeans with Monsanto’s dicamba-tolerance trait comprised a quarter of U.S.

soybeans, and more than 6 percent of all U.S. cropland. By 2018, Monsanto’s

48
dicamba-tolerance trait was in approximately 50 percent of U.S. soybeans. Use of

the three dicamba herbicides has increased commensurately. 

Many farmers have felt, and will continue to feel, compelled by the

increased planting of DT soybeans, and the accompanying increased use of OTT

dicamba, to change from non-DT to DT soybeans. Rob Robinson, CEO and owner

of Rob-See-Co in Waterloo, Nebraska, wrote in a September 14, 2017, letter to the

Administrator of the EPA, “[T]he amount of damage I am hearing about from my

soybean seed customers and sales force is alarming. Even more alarming is the

number of my customers who have told me they will plant all Xtend varieties,

instead of my [non-DT] seed, as a defensive measure against damage from

neighbors who will use Xtend varieties and spray the approved dicamba

product. . . . I find this issue incredibly anticompetitive . . . .” Joe Merschman,

president and CEO of Merschman Seeds, Inc. in West Point, Iowa, wrote in a

September 25, 2018, email to Keigwin of the EPA, “This year we are hearing this

statement over and over again from our farmer customers when it comes to

planning their soybean seed purchases for 2019[:] ‘I guess I will have to plant

dicamba resistant soybeans next year to avoid the off target injury. I cannot afford

to keep getting my soybeans damaged from dicamba.’” Merschman wrote that

market research from the Iowa-Illinois-Missouri area indicated that 59 percent of

soybean acres were expected to be dicamba-tolerant in 2019. Sonny Beck, CEO of

49
the seed company Beck’s Superior Hybrids, wrote to Keigwin on July 27, 2018,

advocating that the new dicamba formulations be restricted to pre-plant use only

even though he himself had sold more than one million bags of Xtend soybean

seeds in 2018. Among his reasons, Beck cited concern that other seed technologies

wouldn’t get a chance to “make an impact on weed resistance,” as farmers

increasingly adopted DT seeds out of fear over dicamba drift.

Professor David Ripplinger of North Dakota State University recounted in a

February 2018 article in Agweek, “The farmers I talk to are almost all going to

grow dicamba soybeans this year because they don’t want to be exposed to the

risk.” Steckel of the University of Tennessee recounted in his August 2018 article,

“Many growers have told me they simply gave up trying to grow non-Xtend

soybeans because they had repeatedly seen dicamba injury in past years—often

multiple times in the same year.” In his letter forwarded to the EPA in June 2018,

Dr. Baldwin wrote, “Dicamba has a chemistry problem that likely cannot be fixed,

or at least no evidence has been provided that it can be successfully applied. If it

can, it will only be through advances in chemistry. As the technology currently

exists, renewing the cotton and soybean registrations will leave the industry no

choice but to plant 100% of the soybean acreage [with] this technology.”

Extending the conditional registrations for OTT use of XtendiMax, Engenia,

and FeXapan creates a substantial the risk that DT soybeans, and possibly DT

50
cotton, will achieve a monopoly or near-monopoly. The likely anti-competitive

effect of the registrations would impose a clear economic cost, but the EPA at no

point identified or took into account this cost.

2. Social Cost

The EPA also entirely failed to acknowledge a social cost that had already

been experienced and was likely to increase. The record contains extensive

evidence that OTT application of dicamba herbicides has torn apart the social

fabric of many farming communities. Major, the Kentucky grain producer, wrote

in his August 2018 email to Keigwin: “This used to be a pretty close area, with

neighbors helping neighbors. This chemical has changed this for quite a few

growers. The applicators of dicamba are damaging their neighbor’s crops and

when they are asked about it the normal answer is, ‘You can’t prove it,’ or ‘I didn’t

do it[.]’” The July 20, 2018, article in Progressive Farmer recounted, “The rise in

off-target dicamba injury has strained the social fabric of rural communities, said

University of Illinois weed scientist Aaron Hager. ‘It’s pitting neighbor against

neighbor,’ he said. ‘Farmers threatening other farmers. I’ve never seen this before

over the use of technology.’” The article recounted further, “[An] Illinois

homeowner, who spoke on the condition of anonymity to protect her from reprisals

in her community, has suffered severe damage to a wide variety of trees . . . as well

as ornamental plants, shrubs and a vegetable garden.” Samples sent to a private

51
laboratory tested positive for dicamba. “‘These are 100-year old oaks,’ she said. 

‘We’re senior citizens and we don’t have the time left in our lives to plant new

trees and watch them get even halfway to maturity. . . . We are farmers,

too . . . . We live in a rural area with generations of families that have been here for

years and years. We’ve known them all our lives. But when we talk to the

farmers, they don’t seem to care that much. There’s no apologies, no offers to

help, nothing.’” In a comment to the Illinois Fertilizer and Chemical Association’s

August 2018 survey, one respondent noted of dicamba use, “In 43 years of

business I have never seen a more divisive product among neighbors both farm and

non-farm.” Another respondent wrote, “This technology cannot continue as is if

we ever wish to raise a susceptible crop or maintain healthy relationships with our

residential and environmental neighbors.” A farmer in Arkansas was shot and

killed in an argument over dicamba damage in 2016.

The severe strain on social relations in farming communities where the new

dicamba herbicides are being applied is a clear social cost, but the EPA did not

identify and take into account this cost. 

C. Substantial Evidence Does Not Support the EPA’s Decision

Considering the record as a whole, we conclude that substantial evidence

does not support the EPA’s October 31, 2018, decision to grant conditional

registrations to XtendiMax, Engenia, and FeXapan for OTT application on DT

52
soybeans and cotton. The EPA found two benefits from the uses, which were

amply supported by evidence in the record. But the EPA failed to perform a proper

analysis of the risks and resulting costs of the uses.

The EPA substantially understated the costs it acknowledged. The EPA

substantially understated the acreage planted with DT soybeans in 2018 and the

resulting use of dicamba in that year. It recounted in its decision document that

Monsanto had “predicted” that 40 million acres of DT soybeans would be planted

in 2018, even though record evidence then before the EPA indicated the actual DT

soybean acreage was much higher and that the combined DT soybean and cotton

acreage was higher still. Further, the EPA recognized that there had been an

enormous increase in dicamba complaints in 2017 and 2018, but it purported to be

agnostic as to whether those complaints under-reported or over-reported the

amount of dicamba damage. In fact, record evidence shows that the complaints

substantially under-reported the actual amount of damage. Finally, the EPA

substantially understated the amount of dicamba damage during the 2017 and 2018

growing years, characterizing the damage as “potential” and “alleged,” and

claiming there was insufficient data from which to estimate the amount of damage. 

In fact, record evidence shows that OTT application of dicamba herbicides in 2017

and 2018 had caused enormous and unprecedented damage. 

53
The EPA also entirely failed to acknowledge other costs. The EPA entirely

failed to acknowledge the substantial degree of non-compliance with the 2017

label, and the likelihood of an even greater degree of non-compliance with the

2018 label. Further, the EPA entirely failed to recognize the economic cost

imposed by the coercion of non-DT farmers to convert to DT crops, and the

resulting anti-competitive effect of that coercion. Finally, the EPA entirely failed

to recognize the enormous social cost to farming communities where use of

dicamba herbicides had turned farmer against farmer, and neighbor against

neighbor.

VII. Post-Argument Request by Petitioners

On May 13, 2020, in the supplemental brief we had ordered pertaining to the

scope of their challenge, petitioners requested (though without making a formal

motion) that we issue a summary decision, to be followed by an opinion. The EPA

moved for permission to file a supplemental brief opposing petitioners’ request, as

well as for judicial notice of an extra-record document. In light of our issuance of

the opinion today, we deny the EPA’s motions. 

VIII. Remedy

The EPA and Monsanto urge us, if we conclude that substantial evidence

does not support the 2018 conditional registrations, to remand without vacatur,

leaving the conditional registrations in effect. We decline to do so.

54
We order remand without vacatur “only in limited circumstances.”

Pollinator Stewardship Council, 806 F.3d at 532 (internal quotation marks

omitted). To determine whether vacatur is appropriate, “we weigh the seriousness

of the agency’s errors against the disruptive consequences of an interim change

that may itself be changed.” Id. (internal quotation marks omitted). We also

consider the extent to which either vacating or leaving the decision in place would

risk environmental harm. Id. We have also “looked at whether the agency would

likely be able to offer better reasoning or whether by complying with procedural

rules, it could adopt the same rule on remand, or whether such fundamental flaws

in the agency’s decision make it unlikely that the same rule would be adopted on

remand.” Id.

Applying these criteria, we vacate the registrations. The EPA made multiple

errors in granting the conditional registrations. As described above, the EPA

substantially understated the risks it acknowledged, and it entirely failed to

acknowledge other risks. We conclude that the “fundamental flaws” in the EPA’s

analysis are so substantial that it is exceedingly “unlikely that the same rule would

be adopted on remand.” Id.

We are aware of the practical effects of our decision. Among other things,

we are aware of the adverse impact on growers who have already purchased DT

soybean and cotton seeds and dicamba products for this year’s growing season,

55
relying on the availability of the herbicides for post-emergent use. As the EPA

explained to us in its brief, arguing against vacatur: “Growers already have

invested in both Xtendimax and accompanying resistant seeds for the 2020

growing season. Vacatur could leave those growers with an unusable pesticide

technology system and force them to expend additional money on alternative seeds

and pesticides.” The EPA had also cautioned in its 2018 decision to grant

conditional registrations, “It is important to note that using registered dicamba

products on dicamba-tolerant cotton or dicamba-tolerant soybean crops that are not

registered specifically for post-emergence use on dicamba-tolerant cotton or

dicamba-tolerant soybean crops is inconsistent with the pesticide’s labeling and a

violation of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).”

We acknowledge the difficulties these growers may have in finding effective and

legal herbicides to protect their DT crops if we grant vacatur. They have been

placed in this situation through no fault of their own. However, the absence of

substantial evidence to support the EPA’s decision compels us to vacate the

registrations.

Petition for review GRANTED. Registrations VACATED. The mandate

shall issue forthwith. 

56