1.107,01/Pii3 Jason Fearneyhough, Director 

Matthew H. Mead, Governor N 2219 Carey Ave. • Cheyenne, WY 82002 

 DEPARTMEN -1 ffliatverit/I.e, Phone: (307) 777-7321 • Fax: (307) 777-6593 

Web: agriculture.wy.gov • Email: wdal®state.wy.0 

The Wyoming Department ofAgriculture is dedicated to the promotion and enhancement of Wyoming's agriculture, natural resources and quality oflift. 

January 14, 2013 

Attention: Team Leader —Debra Rate (Team 9) 

Risk Integration, Minor Use & Emergency Response 

U.S. EPA Office of Pesticide Programs (7505P) 

One Potomac Yard, Room 54900, 

2777 Crystal Drive 

Arlington, VA 22202 

(703) 305-6784 

RE: Re-certification for an emergency exemption for the use of Dimilin 2L (diflubenzuron, EPA 

Reg. #400-461) on alfalfa/hay crops to control Mormon cricket and various grasshopper species 

Section 18 of the amended FIFRA provides the Administrator may exempt a state or federal 

agency from provisions of FIFRA if a determination is made that emergency conditions exist that 

require such exemption. The Wyoming Department of Agriculture (WDA) is applying for recertification for a specific exemption of Dimilin 2L (diflubenzuron, EPA Reg. #400-461) on 

alfalfa/hay crops to control Mormon cricket and various grasshopper species in Wyoming. This 

is the fourth year that WDA has made this request. All previously submitted material remains 

valid as per 40CFR 166.20(b)(5) 

ncerely, 

Polly Cross 

Assistant Manager, Technical Services 

Equal Opportunity in Employment and Services 

BOARD MEMBERS 

Vacant, District I • Jim Hodder, District 2 • Shaun Sims, &oriel 3 • John Moore, District 4 • Alison Lass, Dictriet 5 

Bryan Brost, District 6 • Jim Price, Jr., District 7 

YOUTH BOARD MEMBERS 

Patrick 7immerer Snntheact • Dalin Winter ,: NnrtInstrat • Inhn Manama Snnthweet • Pricker Williams Northeaat 
WYOMING WEED AND PEST COUNCIL

(WWPC)

GOVERNOR, Matt Mead PRESIDENT, John Watson 

__________________________________________________________________________________________ 6607 Campstool Road - Cheyenne, WY 82002-0100 - (307) 777-6585 or 1195 South Guernsey Road – Wheatland, WY 82201 

_______________________________________________________________________________________________________________________________________ 

Executive Directors

Slade Franklin 

State Coordinator, Cheyenne 

Jim Cotterman 

Secretary, Wheatland

Walt Hartung 

Area 1, Cody 

Quade Schmelzle 

Area 2, Gillette 

Wes Waters Vice President 

Area 3, Evansville 

Doug Vickrey 

Area 4, Daniel 

Randy Laughter 

Area 5, Green River 

Lindsay Wheat, Treasurer 

Area 6, Laramie 

January 8, 2013

Wyoming Department of Agriculture

Attn:  Polly Cross – Tech. Services Asst. Manager

6607 Campstool Road

Cheyenne, WY  82002

Mrs. Cross,

On behalf the Wyoming Weed and Pest Council, I would like to request the Wyoming Department of

Agriculture to seek an approval of a Section 18 label for the use of Dimilin to control grasshoppers in

alfalfa.  The twenty‐three Weed and Pest Control Districts in the state work diligently in assisting private,

state and federal land managers in controlling grasshoppers on their respective grounds.  This Section 18

label for Dimilin has historically been an important tool for them in succeeding with their control

programs.  

In Wyoming, grasshoppers have been a significant issue over the last three years.   In 2010 and 2011, the

state experienced higher than average hatches in most parts of the state.  Unmanaged, they would have

had a significant impact on the ecological health of rangeland and croplands both, not to mention a

significant economical impact on the agricultural community.  Through the use of insecticides, mainly

Dimilin, the Weed and Pest Control Districts were able to mitigate their impacts and save the agriculture

community from losses estimated near $11 million dollars for 2010.    A key to that success was the

Section 18 label for the use of Dimilin on alfalfa.   Alfalfa proved to be a major hatching area for the

grasshoppers, and Dimilin was the only insecticide available that would allow the Districts to mitigate

the issue BEFORE the grasshoppers could significantly damage the alfalfa field.   

Although we are not expecting grasshopper outbreaks even near the 2010 and 2011 levels, there are

several areas where we expect higher than normal hatches to occur.    Some of these areas will have

alfalfa fields within them.    The approval of this Section 18 label will help the Weed and Pest Control

Districts to prepare and implement management programs that will mitigate the impacts from any

outbreaks.

Sincerely,

John Watson

President
DIMILIN® is a Registered Trademark of Chemtura Corporation, 199 Benson Road, Middlebury, CT 06749

All applicable directions, restrictions, and precautions on the registered product label for

Dimilin 2L (400-461) are to be followed.

These Use Directions must be in the possession of the user at the time of the pesticide application. 003

It is a violation of Federal law to use this product in a manner inconsistent with its labeling.

FOR CONTROL OF GRASSHOPPERS AND MORMON CRICKETS IN ALFALFA AND MIXED GRASS/ALFALFA HAY

SITES AND ACREAGE TO BE TREATED:

ALFALFA AND MIXED GRASS/ALFALFA HAY

GRASSHOPPERS AND MORMON CRICKETS: For optimum results, apply DIMILIN 2L when grasshoppers/Mormon crickets have reached the 2nd to 3rd

instar stage of development. DIMILIN will not effectively control grasshoppers and Mormon crickets once they reach the adult stage. 

Do not exceed 2 fl. oz. per cutting or 4 fl. oz per acre per year. 

Do not apply closer than 14 days prior to harvest.

Do not apply DIMILIN directly to or allow to drift to water or wetlands. When disposing of equipment wash water or rinsate, do not contaminate water.

Do not plant food or feed crops in DIMILIN treated soils within 1 month following last application, unless DIMILIN is authorized for use on these crops.

Do not enter or allow workers into treated area during the restricted entry interval (REI) of 12 hours.

Do not apply within 25 feet by ground or within 150 feet by air of bodies of water such as lakes, reservoirs, rivers, permanent streams, natural ponds, 

marshes or estuaries. All applications must include a 25 foot buffer vegetative strip within the buffer zone to decrease runoff.

SECTION 18 EMERGENCY EXEMPTION FOR ALFALFA AND MIXED GRASS/ALFALFA HAY

FOR USE ONLY WITHIN THE STATE OF WYOMING

RESTRICTED USE PESTICIDE

Due to toxicity to aquatic invertebrate animals.

For retail sale to and use only by Certified Applicators, or persons under their direct

supervision, and only for those uses covered by the Certified Applicator's certification.

Dimilin® 2L

INSECT GROWTH REGULATOR

SUSPENSION CONCENTRATE

Crops Pests

Application Rate

 (fl oz/acre) Application Timing

Alfalfa and Mixed 

Grass/Alfalfa Hay

Grasshopper 0.75 - 2 Use 1 application on early instar (majority in the 2nd through 4th instar nymphal stages). 

For best results use high rate on heavy infestations or dense foliage. 

Mormon 

cricket

May be used in a RAATs (Reduced Area and Agent Treatment) application on early instars. A RAATs application is an IPM strategy that takes advantage of grasshopper movement and conservation biological control to allow Dimilin 2L to be applied on a reduced 

treated area and at reduced rates, while sustaining acceptable control. 

The rate range to use per acre and amount of area treated will depend on grasshopper/ 

Mormon cricket age, plant canopy and topography. Skip up to 50% of the infested area 

(every other swath) and use the lower rate under uniform topography with early instar 

ages and sparse vegetation. If the majority of the population is late instars, vegetation 

is dense, terrain is considered rough, and conditions are hot during treatment, then the 

coverage and rate of DIMILIN 2L should be increased up to a blanket (100%) coverage 

with 1 fl oz per acre.

Applications may be made after each cutting of alfalfa. Do not apply more than three 

applications per year.

DIMILIN will not effectively control grasshoppers and Mormon crickets once they reach the adult stage

Aerial application: For low/high volume application, apply in 2 to 10 gallons of water per acre. For ULV application, apply in a minimum of 12 fl. ozs. 

total volume per acre.

Ground application: For low/high volume application, apply in 2 to 30 gallons of water per acre. For ULV application, apply in a minimum of 12 fl. ozs. 

total volume per acre.

Regardless of application type, total spray volume used must ensure thorough coverage of the target crop. Aerial and ULV spray mixtures should 

include an evaporation/drift retardant product at use rates prescribed on the specific product label, particularly when conditions are favorable for 

water evaporation (e.g., high air temperature and/or low humidity). When using oil type evaporation/drift retardant products, be sure to maintain a 

ratio of at least 2 parts water to 1 part oil.

For low volume and ULV applications, make sure that the spray mixture in the boom contains the correct concentration of Dimilin 2L before application begins, and be sure that good agitation is maintained throughout mixing and application.
JOB/C406 

Chemtura Corporation 

199 Benson Road 

Middlebury, CT 06749 

203-573-2454 tel

January 3, 2012 

Wyoming Dept. of Agriculture 

Technical Services 

2219 Carey Avenue 

Cheyenne, Wyoming 82002-0100 

 Attention: Polly Cross, Assistant Manager 

 Subject: Letter of Support for Emergency Exemption, Section 18 

 For Dimilin® 2L on Alfalfa in Wyoming 

Dear Ms. Cross, 

 Chemtura Corporation supports the State of Wyoming Section 18 application for 

the use of Dimilin 2L, EPA Reg. No. 400-461, on alfalfa hay and mixed grass/alfalfa hay 

for control of grasshoppers and Mormon crickets. Chemtura agrees to supply 

commercially ready product via our normal channels of trade. 

 We would appreciate it if you would send us a copy of all EPA correspondence 

on this subject to Terri Hass at the above address. Should you have any questions, please 

call Terri at 203-573-2462 or e-mail Terri at terri.hass@chemtura.com. 

 Sincerely, 

 Chemtura Corporation 

 Allen R. Blem 

 Product Registration Mgr., North America