UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

MAR 4 2016 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

MEMORANDUM 

SUBJECT: 

FROM: 

THRU: 

TO: 

BEAD Chemical Profile (BCP) for Registration Review: Fluometuron (PC 

035503) 

Biological 

Sunil Ratnayake

Analysis 

, Ph.D.

Branch 

, Biologist 

\ 

~ ''"'-JI~ ' ~ . ~ ~ 

Jihad Alsadek, Ph.D., Economist ../ ~ ~ jf~ Science Information and Analysis Branch 

Stephen Smearman, Economist L .. __ /. • 7

Economic Analysis Branch ' 

,. 

1 

~ 

Biological and Economic Analysis Division (7503P) 

Mark Suarez, Acting Chief ~ A ---- Biological Analysis Branch 'V\J ~ . 

Diann 

Science 

Sims

Information 

, Chief ~ and Analysis Branch 

Economic 

Timothy Kiely

Analysis , Chief Branch 

sn \ 

\JV

I\. J\ 

\ 

~ 

Biological and Economic Analysis ivision (750 · 

Linsey Walsh, Chemical Review Manager 

Risk Management and Implementation Branch 3 

Pesticide Re-evaluation Division (7508P) 

Peer Review Panel date: September 23, 2015 
SUMMARY 

Fluometuron is a selective herbicide that is used to control broadleaf and grass weeds; cotton is 

the only registered use site. It was first registered in the United States in 1974 and re-registered 

in 2004 (USEPA, 2005). According to the Weed Science Society of America (WSSA), 

fluometuron belongs to the phenyl urea family of herbicides (Group 7). The mechanism of action 

of Group 7 herbicides is the inhibition of photosynthesis photosystem II. Fluometuron usage on 

cotton has decreased almost 90 percent over the years 1998 to 2013. During the time period 

2003-2013, fluometuron annual usage averaged approximately 500,000 pounds active ingredient 

(a.i.) on approximately 686,000 acres of cotton, for an average application rate of 0.80 lbs. a.i. 

per acre. 

Fluometuron is used by growers to help manage weed species such as Palmer amaranth that are 

resistant to glyphosate and to ALS ( acetolactate synthase) inhibiting herbicides, especially in the 

·Southeast and Mid-south regions in the United States. 

INTRODUCTION 

The Biological and Economic Analysis Division (BEAD) Chemical Profile (BCP) provides an 

overview of the pest management roles and quantitative usage information for fluometuron. The 

BCP includes summaries of previous BEAD products and available public and/or private use and 

usage data for fluometuron to describe its role in pest management. Additional information on 

use is available in the fluometuron Label Data Report. Information provided in this BCP may be 

used by stakeholders (e.g., users and registrants), OPP risk assessors, OPP benefit assessors, OPP 

risk managers, and the general public during the Registration Review process of this herbicide. 

USE SITES 

Fluometuron is registered for weed control in cotton production. In 2013, North Carolina was 

issued a 24( c) label for fluometuron use on wild flower fields to control annual broadleaf weeds. 

FORMULATIONS AND APPLICATION METHODS 

Current formulations for fluometuron include a flowable liquid concentrate and an emulsifiable 

concentrate. Application methods include banded, broadcast, directed spray, and soil 

incorporated treatment. 

HISTORY OF FLUOMETURON AND BEAD PRODUCTS 

A search of the BEAD database for previous products for fluometuron indicates that there are no 

records of prior benefits assessments or Section 18 Emergency Exemption Requests. Recent 

Section 18 Emergency Exemption Requests might suggest that a chemical is important for the 

uses granted in the request; however a lack of Section 18 Emergency Exemption Requests is not 

an indication of the relative importance of the chemical. 

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USAGE 

Fluometuron is an herbicide that was registered in the U.S. in 1974. A re-registration eligibility 

decision (RED) document was published in 2005. A Screening Level Usage Analysis (SLUA) 

was prepared by BEAD for fluometuron in 2015 that provides national level poundage applied 

by active ingredient (a.i.) and percent crop treated (PCT) data. The SLUA shows that an annual 

average of 500,000 lbs. active ingredient (a.i.) is applied on cotton. This annual average is based 

on proprietary data and public data that covers the time span from 2004 to 2013 . 

Based on private market data, fluometuron usage on cotton was about 5 million pounds in 1998. 

By 2003 usage had declined to about 600 thousand pounds, apparently due to the rapid adoption 

of glyphosate-tolerant cotton. This is a drastic decrease in the use of fluometuron on cotton, 

almost 90 percent decrease. From 2003-2013, fluometuron annual usage averaged 

approximately 551 ,000 pounds active ingredient (a.i.) on approximately 686,000 acres of cotton, 

for an average application rate of 0.80 lbs. a.i. per acre. 

The overall use of fluometuron decreased significantly after 1998 and this is most likely due to 

the rapid adoption of glyphosate-tolerant cotton (Figures 1 and 2). Slight increase of 

fluometuron use observed around 2011 may be due to the inclusion of fluometuron in herbicide 

resistance management programs (Fig. 2). 

Figure 1. Fluometuron Usage in Pounds A.I. Ap lied (19,28-201_3) 

6,000,000 

0 

N M 'llt Ll"I \I) " co 0\ 0 

8 8 8 8 8 8 8 8 s 

N N N N N N N N N 

Years 

Source: Market Research Data, 1998-2013 

Page 3 

~ N M 

s s s 

N N N 
Figure _2. Fluometuron Total Area Treate~ ~I! :\. cr j_ ~8-~01~2 

6,000,000 

0 00 en 0 .... N rt) "It U"\ ID ,.... 00 en 0 .... N t'I') 

~ ~ 8 8 8 8 8 8 8 8 8 8 s s s .... 

0 

I 

.... .... N N N N N N N N N N N N N N 

Years 

l - --- - --

Source: Market Research Data, 1998-2013 

Geographic Distribution of Fluometuron Use 

As the following map (Figure 3) shows, Texas, Arkansas and Tennessee are the states with the 

highest usage of fluometuron in terms total area treated which reflects the use on cotton. 

Page4 
Total Acres Treated 

~ NoData 

CJ < 1,000 

1, 001 - 10,000 

.. 10.001 - 45,000 

.. 45.001 -100,000 

.. >100,001 

Figure 3. Average annual total acres treated of fluometuron (2009-2013). 

(Source: Market Research Data) 

The map included herein is for general use in the registration review process. The map provides 

a very broad geographical view of the average annual total acres treated (TAT) with fluometuron 

over the period from 2009 to 2013. The map units are average annual total acres treated, which 

accounts for all agricultural acreage treated with this chemical and includes multiple treatments 

to the same area. The map shows the use offluometuron is mostly in Texas, Arkansas, 

Tennessee, and to a lesser degree in Missouri, Mississippi and Georgia. Although cotton is 

produced in Arizona and California, the differences in climate, cotton varieties grown, and the 

differences in the weed spectrum found in that region may be the factors contributed to the less 

usage of, fluometuron in that region. 

The data used to make these maps have many limitations. Any interpretation of the maps should 

consider the underlying data and the associated limitations carefully. For example, there may be 

significant differences in the crop acres grown between states and there may be variation in the 

percent of each of the various crops treated by the pesticide. 

TAT is based on private market surveys of pesticide use in agriculture averaged over the last five 

years (Market Research Data). These surveys cover about 60 crops and are targeted in states that 

produce the majority of the crop. Although the surveys capture most of the use of a particular 

Page 5 
active ingredient in agriculture, there are several limitations to these surveys. 

• States with minor production of a surveyed crop are not sampled 

• Not all types of pesticides are surveyed in every crop in every year 

• Many specialty crops with very small acreages are not included in the survey 

The result of these limitations is that states that show no acres treated may actually have a small 

amount of the active ingredient being used. In some cases, the displayed TAT may be distorted 

because the surveyed crops and the reported pesticide usage (or TAT) does not accurately 

represent the actual pesticide usage on the crops produced in the state. 

The reader should pay particular attention to the figure legends and realize that a map prepared 

for a particular chemical is not directly comparable to a map prepared for a different chemical as 

the total acre treatment intervals used in the legend will likely be different. 

BIOLOGICAL ASPECTS RELEVANT TO FLUOMETURON 

Fluometuron is a selective and systemic phenyl urea herbicide which belongs WSSA Group 7 

(WSSA, 2015). The mechanism of action of this herbicide group is inhibition of photosynthesis 

at photo system II (Herbicide Handbook, 2014 ). Fluometuron is readily absorbed by roots and 

translocated·to the shoots predominantly by xylem. Foliar applied fluometuron is not rapidly 

absorbed; it has little or no translocation from the leaf to the other parts of the plants through 

phloem tissue. (Herbicide Handbook, 2014 ). 

ROLE OF FLUOMETURON IN PEST MANAGEMENT 

Fluometuron is used to control many annual grasses and broadleaf weed species found in cotton 

production. As described under the usage section, Texas, Tennessee, and Georgia are the states 

with the highest usage of fluometuron during the 2009 to 2013 time frame. 

Fluometuron provides a wide application window and can be applied as pre-plant, at-plant, preemergence and post-emergence treatments. Application of fluometuron is recommended for the 

control of annual grass weed species such as barnyardgrass (Echinochloa crus-galli), crabgrass 

(Digitaria sanguinalis), fall panicum (Panicum dichotomiflorum), foxtail spp. (Setaria spp.), 

goosegrass (Eleusine indica), and broadleaf signalgrass (Brachiaria platyphylla). In addition, 

fluometuron controls major broadleaf weed species, including annual morning-glory (lpomoea 

spp.), cocklebur (Xanthium strumarium), sicklepod (Senna obtusifolia) and Palmer amaranth 

(Amaranthus palmeri). Other broadleaf weeds controlled by fluometuron include Florida pusley 

(Richardia scabra), lambsquarters (Chenopodium album), prickly sida (Sida spinosa), common 

ragweed (Ambrosia artemisiifolia), sesbania (Sesbania exaltata), Pennsylvania smartweed 

(Polygonum pensylvanicum), and spurge (Euphorbia) species. (Herbicide Handbook, 2014). 

Glyphosate resistant weeds, especially glyphosate-resistant Palmer amaranth (Amaranthus 

palmeri) are highly problematic for cotton growers in the Southeast and Mid-south regions in the 

United States (Barnett et al., 2013). Fluometuron can be tank mixed with other compatible 

herbicides to increase the efficacy and the range of weeds controlled. For example, tank-mixing 

Page 6 
fluometuron with glufosinate increased the control of large Palmer amaranth plants by 28% 

compared to the glufosinate alone treatment (Barnett et al., 2013). Also, tank-mixing of 

fluometuron with treflan is recommended as a pre-plant Incorporated (PPI) treatment to delay the 

emergence of glyphosate resistant Palmer amaranth in Roundup ready cotton production 

(Clemson Co-operative Extension, 2012). Fluometuron is also used to control ALS- resistant 

Palmer amaranth in cotton production (Clemson Co-operative Extension, 2012). Fluometuron 

use in herbicide resistance management programs may be responsible for the slight increase in 

usage in recent years. (Fig. 2). Eleven weed species have developed resistance to the mechanism 

of action of group 7 herbicides in the United States (Heap, 2015). 

The observed decline in the use of fluometuron over the 1998-2013 time period may be due to 

the rapid adoption of glyphosate-tolerant cotton. However, usage of fluometuron remained 

relatively constant after 2003. This relatively consistent usage may be due to the use of 

fluometuron on non-GMO cotton as well as other niche uses such as use on wild flower fields to 

control annual broadleaf weeds. 

DATA NEEDS 

There are no current BEAD data needs for fluometuron. As the registration review process 

progresses, certain data needs may arise. -

REFERENCES: 

Barnett, K. A., Culpepper, A. S., York, A. C., and L. E. Stecker. 2013. Palmer Amaranth 

(Amaranthus Palmeri) Control by Glufosinate plus Fluometuron Applied Postemergence 

to WideStrike® Cotton. Weed Science Vol 27, No. 2, pp. 291-297. 

Biological and Economic Analysis Division (BEAD). 2015. Fluometuron (SLUA) Screening 

Level Usage Analysis. Office of Pesticide Programs, US Envirorimental Protection 

Agency. 

Clemson Cooperative Extension. 2012. Herbicide Programs for Weed Control in Cotton. Online 

Publication. Available at: 

https ://www .clemson.edu/ extension/ county/hampton/programs/row crops/Cotton/mikem 

arshall.pdf. Accessed on September 30, 2015. 

GMO Compass. 2013. USA: Cultivation of GM plants. Online Publication. Available at: 

http://www.gmocompass.org/eng/agri biotechnology/gmo planting/506.usa cultivation gm plants 2013 

.html. Accessed on Sep. 17, 2015. 

Heap, I. 2015. The International Survey of Herbicide Resistant Weeds. Online Publication. 

Available at: http://www.weedscience.org/summarv/ResistbyActive.aspx. Accessed on 

Sep. 17, 2015. 

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Herbicide Handbook. 2014. 1 oth edition. Weed Science Society of America. Fluometuron. 810 

E. 10th Street, Lawrence, KS 66044-8897. Pp. 214-215. 

Market Research Data (MRD). Various years. Data collected and sold by a private market 

research firm. Data collected on pesticide use for about 60 crops by annual surveys of 

agricultural users in the continental United States. Survey methodology provides 

statistically valid results, typically at the state level. 

USEPA (United States Environment Protection Agency). 2005. Registration Eligibility Decision 

for Fluometuron. Available at: 

http://www.epa.gov/pesticides/reregistration/REDs/fluometuron red. pdf. 

Accessed on July 08, 2015 

WSSA, (Weed Science Society of America). (Undated). Summary of Herbicide Mechanism of 

Action. Online Publication. Available at: http://wssa.net/wp-content/uploads/WSSAMechanism-of-Action.pdf . Accessed on Sep. 16, 2015. 

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