UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

SEP 2 5 2014 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

MEMORANDUM 

SUBJECT: 

FROM: 

THRU: 

TO: 

BEAD Response to Dow AgroSciences Comments on Chemical Profile and Label 

Use Reports for the Clopyralid Case (117401, 117403, 117404, and 117423) 

Biological 

Sunil Ratnayake, 

Analysis 

Biologist 

Branch ~ 

/1. _ 

c T 

t_ 

\ ~ . . 

Sepehr 

Science 

Haddad, 

Information 

Envirorunental 

and Analysis 

Protection 

Branch 

Specialist~-ju 1~ 

Economic 

Stephen Smearman, 

Analysis Branch 

Economist ~ 

Biological and Economic Analysis Division (7503P) 

Amet Jones, Chief d__ ~ .for IJ'f~ -;T"" ~ Biological Analysis B~~ / /~ J , 

Diann 

Science 

Sims, 

Information 

Chief Jil~ and Analysis Branch 

Economic 

Timothy Kiely, 

Analysis 

Chief 

Branch ~ r"' V v 

1\ 

'--~ Biological and Economic Analysi Division (750 

Steve Snyderman, Chemical Review Manager 

Pesticide Re-evaluation Division (7508P) 

Peer Review Panel date: September 23, 2014 

BEAD has reviewed the comments provided by Dow AgroSciences, (Submission to Docket No. 

EPA-HQ-OPP-2014-0167, dated May 26th, 2014). We appreciated the comments from the 

registrant. Our responses are as follows: 
Registrant Comment: Clopyralid is not labeled for use in alfalfa, almonds, beans, chestnuts, 

filberts, lentils, macadamia nuts, peas, pecans, pistachio nuts, potatoes, safflower, sorghum, 

soybeans, sunflowers, and walnuts. All references to non-labeled crops should be removed from 

the documents. 

EPA Response: Thank you for your response. All appropriate changes have been 

made to the BCP to reflect only registered use sites, and a revised version of the 

BCP will be placed in the docket. 

Registrant Comment: The statement on p.8 of the BCP that it has been reported that biotypes of 

9 weed species have developed resistance to clopyralid is incorrect. 

EPA Response: BEAD agrees with the registrant statement that the number of 

weeds with resistance to clopyralid on page no. 8 of the BCP is incorrect. The 

statement on page 8 under the Biological Aspects Relevant to Clopyralid will be 

revised to reflect that clopyralid belongs to the Group 0 herbicides (HRAC 

classification) and according to the International Survey of Herbicide Resistant 

Weeds, biotypes of 8 weed species have developed resistance to the mode of 

action of Group 0 herbicides in the United States. However, no reports could be 

found on the development of weed resistance, specifically to clopyralid in the 

United States. 

Registrant Comment: EPA registration number 62719-570 Surestart Max labeled rate is 3.5 

pt not 3 pt as per HED document. The normal rate at 3pt/acre should equal 0. 1425 lb ai /a (not 

0.149lb ai/a). The max rate at 3.5 pt/acre should equal 0.166lb ai/a (0.126lb ae/a) 

EPA Response: The HED Label Report and the EFED Label Report reflect 

different purposes and focus on different aspects of a chemical's use pattern. The 

HED Label Report Document only lists the maximum single application rate, 

which is 3 pt/acre, for the purpose of occupational risk assessments. The 

registrant is correct that the maximum seasonal labeled rate, which is an important 

parameter in ecological risk assessments, is 3.5 pt and that is reflected in the 

EFED Label Report Document. 

Registrant Comment: EPA registration number 62719-315 Hornet WDG 

The max rate for use in corn is 0.187lb ai/a when using Hornet WDG. Note: there is a further 

restriction for the use of clopyralid on field corn when other products containing clopyralid are 

used in the same season on field corn. The max use rate is 0.25 lb ae/a. 

EPA Response: The registrant is correct that the max rate for corn is 0.187 lb 

a.i./a. The other lower rate shown (2 ounces/acre) is for field corn grown for 

silage only in New York State per the label. 

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Registrant Comment: EPA registration number 62719-262 TURF FERTILIZER CONTAINS 

CONFRONT 

Note that 0.75 lb/ a.i listed as the heavy rate ofuse is actually a combined rate for both active 

ingredients triclopyr and clopyralid. It is not the use rate of clopyralid alone. 

EPA Response: EPA appreciates the clarification. The rates for this registration 

are captured per the label directions. No changes to the report are needed. 

Registrant Comment: EPA registration number 62719-86 Curtail M 

Max use rate in flax is 0.85 pt. per acre (not 1.75 pt. acre) 

EPA Response: The max use rate for this product appears on the report as 0.85 pt. 

per acre, as noted. The 1.75 pt. per acre rate is associated with the SLN 

ND090003, whose parent label is 62719-86. Thus, both products have the same 

name, Curtail M, but different registration numbers. No changes to report are 

required. · 

Registrant Comment: EPA registration number 62719-259 Transline 

REI specified on label is 12 hours (sheet indicates NS). 

EPA Response: BEAD agrees that 12 hour REI should appear in the report rather 

than NS and will .make the necessary changes to the affected reports. 

Registrant Comment: EPA registration number 62719-259 Transline 

Cottonwood and Poplar can receive a rate up to 1.3 3 pt/acre per season; ''Apply at a rate of 1/3 

to 1 113 pints/acre in eucalyptus tree plantations and 1/3 to 2/3 pints/ acre in cottonwood/poplar 

plantations. Sequential applications may be made as long as the total rate per annual use season 

does not exceed 1 113 pints per acre'' 

EPA Response: The clarification is appreciated. However, the label for 

registration number 62719-259 is not explicit in its language on the number of 

applications per year, hence the NS in the reports. The same label statement was 

used to capture the total rate per annual use season of 1.33 pt /a. "Sequential 

applications may be made as long as the total rate per annual use season does not 

exceed 1 1/3 pints per acre". No changes to report are required. 

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Registrant Comment: EPA registration number 62719-645 Sendaro (GF-2791) 

The Aquatic food use site ''SWAMPS/MARSHES/WETLANDS/STAGNANT WATER'' is not 

labeled for Sendaro and is not appropriate for a product containing clopyralid. The max rate at 

1. 75 pt/acre should equal 0.66 lb ail a (0.5 lb ae/a). This equates to the highest use rate of 

clopyralid for food uses. 

EPA Response: According to the label language, it is permissible to treat nonirrigation ditch banks, seasonally dry wetlands (such as flood plains, deltas, 

marshes, swamps, or bogs) and transitional areas between upland and lowland 

sites. Sendero can be used to the water's edge. We are aware of that directions 

that the a.i. is not to be applied directly to water and to take precautions to 

minimize spray drift onto water. These precautions are captured in the issues 

statements that accompany the report. No changes to report are required. 

REFERENCES 

EPA 2013, BEAD Chemical Profile (BCP) for Registration Review: Clopyralid Case (117401, 

117403, 117404, and 117423) 

Dow AgroSciences, 2014 (Submission to Docket No. EPA-HQ-OPP-2014-0167), dated May 

26th,2014 

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