### Page 2 of 47 

# T ABLE OF 

# C ONTENTS



## 1. EXECUTIVE SUMMARY

................................ ................................ ................................ .... 3

2. INTRODUCTION

................................ ................................ ................................ .................. 4

3. USE CHARACTERIZATION

................................ ................................ ................................ 5

4. CONCLUSIONS FROM PREVIOUS ASSESSMENTS

................................ ..................... 11

4.1. Ecological Risk Assessments

................................ ................................ ......................... 11

4.2. Drinking Water Exposure Assessments

................................ ................................ ......... 12

4.3. Clean Water Act Programs

................................ ................................ ............................. 13

5. ENVIRONMENTAL FATE AND TRANSPORT

................................ ............................... 13

5.1. Transformation Products

................................ ................................ ................................ 15

6. R ECEPTORS

................................ ................................ ................................ ........................ 16

6.1. Effects to Aquatic Organisms

................................ ................................ ........................ 17

6.2. Effects to Terrestrial Organisms

................................ ................................ .................... 17

6.3. Ecological Incidents

................................ ................................ ................................ ....... 19

6.3.1. Ecological Incident Information System

................................ ................................ ..... 19

6.3.2. Avian Monitoring System

................................ ................................ ............................ 20

6. 3.3. Aggregate Incident Database

................................ ................................ ..................... 20

7. EXPOSURE PATHWAYS OF CONCERN

................................ ................................ ........ 20

8. ANALYSIS PLAN

................................ ................................ ................................ ............... 21

8.1. Stressors of Concern

................................ ................................ ................................ ....... 2 1

8.1.1. Ecological Risk Assessment

................................ ................................ ........................ 21

8.1.2. Drinking Water Assessment

................................ ................................ ........................ 21

8.2. Measures of Exposure

................................ ................................ ................................ .... 21

8.3. Measures of Effect

................................ ................................ ................................ ......... 22

8.4. Endangered Species Assessments

................................ ................................ .................. 22

8.5. Endocrine Disruptor Screening Program

................................ ................................ ....... 22

9. PRELIMINARY IDENTIFICATION OF DATA GAPS

................................ ..................... 22

9.1. Environmental Fate

................................ ................................ ................................ ........ 22

9.2. Effects

................................ ................................ ................................ ............................. 24

10. REFERENCES

................................ ................................ ................................ .................. 28

Appendix A. SIP and STIR Results

................................ ................................ .............................. 31

Appendix B. EIIS Incidents

................................ ................................ ................................ .......... 33

### Page 3 of 47 

## 1. EXECUTIVE SUMMARY

The Environmental Fate and Effects Division (EFED) has completed the preliminary problem

formulation for the ecological risk, environmental fate, endangered species, a nd drinking water

assessments to be conducted as part of the registration review of clopyralid (PC code 117403 ;

CAS Registry Number 1702

- 17

- 6 ) . This document also covers three registered clopyralid salts

(clopyralid monoethanolamine salt, PC code 117401, CAS #57754

- 85

- 5; clopyralid

triethanolamine, PC code 117404, CAS #119308

- 91

- 7; clopyralid potassium, PC code 117423,

CAS #58509

- 83

- 4)

. Unless otherwise specified, references to “clopyralid” throughout this

document include clopyralid and its three registered salts.

The problem formulation describes the methods planned for the completion of drinking water

and ecological r isk assessment s and provide s an ove rview of the environmental fate, ecological

effects , and potential risks associated with the use of clopyralid . The problem formulation also

addresses uncertain ties unique to risk assessment of clopyralid . This document identifies

ad ditional studies that would be beneficial to the conduct of an ecological risk assessment.

These studies are listed below; see Section 9 for additional details an d explanation. Unless

otherwise noted, studies are requested for clopyralid acid ( PC code 117403)

.

Environmental fate and transport data gaps :

• 835.4100 Aerobic soil metabolism (3 additional soils)

• 835.4300 Aerobic aquatic metabolism (2 sediments)

• 850.610 0 ECM and ILV studies in water, soil , and compost

• Non

- guideline Dissipation study in compost

Ecotoxicology data gap s:

• Aquatic: 1



## o 850.1300 Chronic freshwater invertebrate

o 850.1400 Freshwater fish early

- life stage

o 850.4400 Aquatic vascular plant growth

o 850.4500 Aquatic non

- vascular plant growth ( 2 additional species)

o 850.4550 Cyanobacteria t oxicity

• Terrestrial

o 850.2100 Avian acute oral toxicity (passerine species)

o 850.2300 Avian reproduction (upland game species)

o 850.4100 Terrestrial plant: Tier I I seedling emergence (clopyralid , clopyralid

monoethanolamine salt, clopyralid triethanolamine, and clopyralid potassium )

o 850.4150 Terrestrial plant: Tier II vegetative vigor ( clopyralid, clopyralid

monoethanolamine salt, clopyralid triethanolamine, clopyr alid potassium , and

typical end use products that are co

- formulated with other herbicides )

1 

### Note that there are additional 40 CFR Part 158 aquatic ecotoxicology data gaps listed in 

### Table 12 of this

document that are not requested at this time because they are not expected to impact the risk assessment . These

include 850.1025 Acute oyster shell deposition, 850.1035 Acute mysid, 850.1075 Acute saltwater fish, 850.1350

Chronic saltwater invertebrate, and 850.1400 Saltwater fish early

- life stage. See 

### Table 12 i n Section 9.2 for

additional explanation.

### Page 4 of 47 

## Major uncertainties in the assessment of clopyralid include (1) risk to non

- target terrestrial plants

from irrigation water contaminated with clopyralid and (2) pot ential synergism of herbicides in

products that conta in multiple active ingredients:

Data to better understand risk from residues in groundwater used as irrigation water:

Clopyralid is mobile and persistent (see Section 5 ) and has been detected in groundwater

. Incidents reported for other picolinic acid herbicides demonstrate the potential for groundwater

contaminated with these herbicides to damage non

- target te rrestrial plants when the groundwater

is used for irrigation (USEPA, 2013). Screening level calculations comparing the highest

concentration of clopyralid detected in groundwater to the most sensitive terrestrial plant

NOAEC available show that less than o ne inch of irrigation water would be required to reach this

endpoint. This estimate is expected to decrease ( i.e. , the NOAEC will be reached with even less

irrigation water) when updated groundwater modeling exposure estimates and more refined

terrestrial plant toxicity data become available.

Additional data are recommended to better understand the potential for risk due to residues of

clopyralid in groundwater. Studies that would be useful inclu de a prospective groundwater

monitoring study or studies to refine groundwater modeling inputs for the Pesticide Root Zone

Model for Groundwater (PRZM

- GW) model. A prospective groundwater monitoring study

could be used to determine where groundwater conce rns are likely to occur and whether

predictions based on laboratory data are observed in the field. Additionally, it could be used to

determine vulnerability of different areas. Data to refine inputs to PRZM

- GW may be used to

refine modeling estimates of groundwater concentrations. Studies may involve understanding

sorption or degradation in subsurface environments. It is recommended that a protocol be

submitted, prior to conducting any of these studies. In the absence of more suitable inputs or

scenar ios, EECs generated from PRZM

- GW in the same fashion as EDWCs for gro undwater

used as drinking water will be used to characterize risks to terrestrial plants from residues in

irrigation water obtained from groundwater sources.

Terrestrial plant studies us ing co

- formulated TEPs to identify synergistic effects:

Clopyralid is co

- formulated with many other herbicides, including 2,4

- D, acetochlor,

aminopyralid, benfluralin, dicamba, flumetsulam, fluroxypyr, MCPA, nicosulfuron, rimsulfuron,

thifensulfuron, tric lopyr, and trifluralin. Data on other picolinic acid herbicides suggest that

chemicals in this class may exhibit synergistic terrestrial plant toxicity when co

- formulated with

other herbicides (USEPA, 2013) . Data on representative typical end use product s (TEPs) is

needed to evaluate this potential risk. The registrant should justify the choice of TEPs used for

these studies. The data can be limited to vegetative vigor studies, which are expected to be more

sensitive than seedling emergence studies, and can include only the crops most sensitive to

clopyralid . In the existing terrestrial plant studies, these include o nion, snap bean, soybean,

sunflower, tomato , and wheat

.

2. INTRODUCTION

Clopyralid (3,6

- dichloropyridine

- 2

- carboxylic acid) is a picolinic acid herbicide

. Picolinic acid

herbicides are auxin growth regulators, which mimic naturally occurring plant hormones, thereby

disrupting growth processes and causing abnormal growth patterns in plants. Registered uses

### Page 5 of 47 

## comprise many agricultural and non

- agricultural use sites, including residential turf uses.

Clopyralid is a persistent and mobile compound that is likely to leach to groundwater and may be

transported to surface water by spray drift or runoff. NAWQA monitoring data confirm these

transport routes

. Clopyralid residues have also been found in compost.

EFED evaluated recent ecological risk assessments for clopyralid in association with the most

recent toxicity, exposure, and usage information to determine if sufficient data are available to

support registration review. The most r ecent EFED risk assessment for clopyralid is a 20 12

Section 3 new use assessment for apple, leafy Brassica subgroup 5B, and rapeseed subgroup

20A ( USEPA, 2012 b ). In addition, EFED considered the latest Agency scienc e policies and risk

assessment methodologies.

3. USE CHARACTERIZATION

Clopyralid was first registered in the United States in 1 98 7 for use as an herbicide.

Clopyralid is formulated as an emulsifiable, flowable, soluble concentrate, as water dispersible

granules , as granules, and as dust in multiple end

- use products. Clopyralid is registered for use

on a variety of agricultural, forest, commercial, and residential areas and may be applied via

aircraft, ground sprayer, hand

- held sprayer, and boom sprayer

. Clopyralid may also be applied

to forest plantings via broadcast, high volume spray, spot treatment, stump treatment, girdle

treatment, frill treatment, tree wound treatment, and tree injection. There are 64 active Section 3

registrations and 41 active Section 24(c) special local needs registrations in 20 states.

Registered agricultural use sites now include alfalfa, apples, almonds, asparagus, barley, beans,

brassica leafy greens, canola, chestnuts, cherries, cole crops, conservation resource progra m

(CRP) , corn (field, pop, and sweet), cranberries, filberts, hickory nuts, lentils, macadamia nuts,

mint, oats, pasture, rangeland, peas, peaches, pecans, pistachio nuts, potatoes, rapeseed,

safflower, sorghum, soybeans, spinach, strawberries, sugar beets , sunflower, teff, wheat, and

walnuts. Registered non

- agricultural use sites now include cemeteries, farm buildings,

fencerows, industrial sites, ornamental lawns and turf, ornamentals trees, athletic fields, golf

fairways, parks, and rights

- of

- way.

Ba sed on private market usage data from 1998 to 2011, agricultural usage averaged

approximately 880,000 pounds active ingredient (a.i.) applied annually on approximately 10

million acres treated. The average a.i. rate over this time period was 0.085 pounds a.i./acre.

Between 2004 and 2011, 6 0,000 pounds of clopyralid were applied to sugar beets

, covering an

average of 45% and a maximum of 85% of the U.S. sugar beet crop. Other major uses include

barley (40,000 lbs, 15% of crop) , corn (400,000 lbs, 5% of crop) , and wheat (300,000 lbs, 5% of

crop). Clopyralid is formulated as liquid concentrates that are mixed with water and applied as a

spray. The maximum single application rate that has been previously assessed is 0.5 lb a.i./A.

Table 1 details the registered use patterns for clopyralid acid (PC code 117403; MW: 192 ), Table

2 for clopyralid monoethanolamine salt (PC code 117401; MW: 252.07 ), Table 3 for clopyralid

triethanolamine (PC code 117404; MW: 340.18 ), and Table 4 for clopyralid potassium (PC code

### Page 6 of 47 

## 117423; MW: 230 )

. Though these are four distin ct chemical moieties, they will be assessed

together using the acid equivalence (a.e.) method. That is, only the clopyralid acid component

will be assessed and the application rates of the monoethanolamine, triethanolamine, and

potassium salts will be adj usted to account for only clopyralid acid. EFED will use application

scenarios that result in maximum exposure scenarios for a given use for the risk assessment.

Some use patterns are not sufficiently characterized to permit ready calculation of a maxi mum

application rate per acre, or else involve very broad use sites. More information on the following

items would reduce uncertainty regarding such uses in the risk assessment:

• Some labels have instructions for applications to trees (cut surface, cut

- stump treatment, tree

injection, hack and squirt treatment, and frill and girdle method). The label should specify

the maximum amount of clo pyralid that may be applied per tree ( e.g ., as a function of trunk

diameter), as well as the maximum number of trees that may be treated per acre. This is

because maximum application rates (both single and total annual) in lbs a.i or a.e./A are

needed in order to model exposures resulting from t hese types of uses. Additionally, the

maximum number of applications per year and minimum retreatment interval should be

specified for these uses.

• The labels have several nonspecific use sites. These broadly

- categorized use sites will

require EFED to emp loy the assumption that clopyralid can be used at a broad range of

agricultural, commercial, residential, and forest sites. These use sites will also necessitate the

assumption that application may occur to both aquatic and terrestrial environments. The

following are examples of nonspecific use sites:

o non

- irrigation ditch banks, seasonally dry wetlands (such as flood plains, deltas,

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

dry, ditchbank weeds, shoreline weeds, n on

- cropland areas, and natural areas.

The Agency encourages that use site descriptions be made as specific as possible, so that

potential use areas are not broader than necessary. Vague use site descriptions can impact

assumptions made when doing proxim ity analysis for determinations on the potential risks to

federally listed threatened/endangered (hereafter referred to as “listed”) species.

• Some restrictions are specified on a product basis rather than on an active ingredient basis.

• Some labels only include a maximum sin gle application rate. They do not include a

maximum annual or seasonal application rate, maximum number of applications, o r

minimum retreatment interval

. Any absence of information will result in conservative

assumptions as illustrat ed in the following examples:

o A maximum single application rate is specified with a re

- application interval of 7

days without specifying a maximum annual rate may result in an assumption of 52

applications with 7

- day intervals;

o A label that does not preclu de aerial applications will likely result in an assumption of

aerial pesticide applications;

o A label that does not specify an application interval may result in assumptions of

short application intervals such as 1

- or 3

- day intervals.

• Some labels with mult iple active ingredients, where acid equivalents are relevant, provide

acid equivalent restrictions but do not specify to which active ingredient the limitations

apply.

### Page 7 of 47 Table 1 . Uses Site and Application Information for Clopyralid Acid (PC 117403)

Use Site Formulation

Type 1 Max. Rate

(lbs a.e ./Acre) Max. No. of

Applications

per Year Min.

Application

Interval Application

Methods Comments

Single Annual

Agricultural

Fallow /

Idleland

Conservation

Reserve EC 0.5748

NS NS NS Broadcast

-

Aerial Before seeding

Foliar

Established

plantings

Weed

p ostemergence EC 0.5748 Broadcast

-

Ground

Barley EC 0.1289

NS NS NS Broadcast

-

Aerial Post emergence

EC 0.1316 Broadcast

-

Ground

Corn, Field DF, EC 0.2252 NS NS

NS Broadcast

- Ground

Band treatment

Burndown treatment

Soil incorporated

treatment Preplant,

Preemergence

Postemergence

Spike s tage

W eed

p ost emergence

0.1193 0.2386 2 Broadcast

- A erial

Band treatment Preplant,

Postemergence

Corn, Sweet EC 0.1193 0.2386 2 NS Broadcast

- A erial

and Ground

Band treatment Preplant,

Postemergence

Flax EC 0.0922 0.0922 1 NS Broadcast

- Aerial

and Ground Postemergence

Golf Course

Turf EC, SC,

Dust 0.1237 NS 2 NS Broadcast

-

Ground Foliar

Grasses Grown

for Seed EC 0.1844 0.1844 NS 21 Broadcast

- Aerial

and Ground Preharvest

Postemergence

Postharvest 0.1193 0.2386

Nonagricultural

R ight

- of

- Way /

Fencerows /

Hedgerow s EC, SC 0.6611

NS NS NS Broadcast

- G round

Foliar

0.5748 Broadcast

- A erial

Nursery Stock EC 0.6611 0.6611 NS NS Broadcast

- G round Foliar

Oats EC 0.1289 0.1289 NS NS Broadcast

- Aerial

and Ground Postemergence

Ornamental

and/or Shade

Trees EC 0.6611 NS NS NS Broadcast

- Ground Foliar

Ornamental

Grasses EC 0.6611 NS NS NS Broadcast

- Ground Foliar

Ornamental

Herbaceous

Plants EC 0.6611 NS NS NS Broadcast

- Ground Foliar

Ornamental

Lawns and Turf G, EC, SC,

Dust 0.2895 NS NS NS Broadcast

- Ground Foliar

Ornamental

Sod Farm

(Turf) EC, SC 0.2895 NS NS NS Broadcast

- Ground Foliar

Ornamental

(unspecified) EC 0.3303 0.3303 NS NS Broadcast

- Ground Foliar

Pastures EC 0.5748 NS NS NS Broadcast

- Aerial

and Ground Foliar

Paved Areas

(Private Roads/

Sidewalks) EC 0.0631 NS 2 NS Broadcast

- Ground

--

Rangelands EC 0.5748 0.5748 NS NS Broadcast

- Aerial

and Ground Foliar

Recreation

Area Lawns EC, SC,

Dust 0.6611 NS NS NS Broadcast

- Ground Foliar

### Page 8 of 47 Wheat EC 0.1289 0.1289 NS NS Broadcast

- Aerial

and Ground Postemergence



### NS

- Not Specified

1 

### DF

- Water Dispersable Granules (Dry Flowable); EC

- Emulsifiable Concentrate; G

- Granular; SC

- Soluble

Concentrate/Liquid



### Table 2 . Uses Site and Application Information for Clopyralid Monoethanolamine Salt (PC

117401 )

Use Site Formulation

Type 1 Max. Rate

(lbs a.e ./Acre) Max. No. of

Applications

per Year Min.

Application

Interval Application

Methods Comments

Single Annual

Agricultural

Fallow /

Idleland

Conservation

Reserve EC 0.5238 0.5238 NS

NS Broadcast

- Aerial, Ground

(foliar, spot, stump,

tree injection, girdle

treatment) Fallow,

Foliar

, Established

plantings , When

needed,

P ost harvest SC 0.3827 NS 2

Apple EC 0.2493 0.2493 NS NS Broadcast

-

Ground Bearing,

Nonbearing

Asparagus EC 0.251 0.251 NS NS Broadcast

- Ground, Band

treatment, Spot

treatment Preharvest, During

Harvest, Postharvest

Barley EC 0.1330 0.1330

NS NS Broadcast

- Aerial, Ground (Band

treatment, Spot

treatment) Preharvest, Foliar

SC 0.127 0.190

Beets

(unspecified) EC 0.1898 0.1898 NS NS Broadcast

-

Ground Foliar

Blueberry EC 0.1251 0.2502 2 NS Ground (Direct

Spray, Soil

Broadcast, Spot

treatment, Wipe

on/Wiper treatment Post

- bloom,

Harvest, Pre

- bloom

Brassica (Head

and Stem)

Vegetables EC 0.189 0.189 NS NS Ground (Broadcast,

Spray) Foliar

Canola/Rape EC 0.1898 NS 1 NS Broadcast

- Aerial, Ground Foliar

Chard, Swiss EC 0.189 NS 1 NS Broadcast

-

Ground Foliar

Christmas Tree

Plantation EC 0.251 0.251 NS NS Ground (Broadcast,

Band, Spot

treatment) Foliar

Cole Crops EC 0.1898 0.2506 NS NS Ground (Broadcast,

Spray treatment) Foliar

Commercial/

Industrail

Lawns G 0.1883 NS 2 NS Broadcast

- Ground Foliar

Corn, Field EC 0.1316 0.2633 2

NS Broadcast

- Ground

Band treatment

Direct, Spot

treatment Foliar,

Preplant,

Postemergence

0.2492 0.2493 2 Broadcast

- Aerial

treatment

Corn, Pop EC 0.1316 0.2633 NS NS Ground (Broadcast,

Direct Spray

treatment) Postemergence

Corn, Sweet EC 0.251 0.251 2 21 Broadcast

– Aerial.

Ground (Broadcast,

Band, Direct

treatment Foliar, Preplant,

Postemergence

Cottonwoods

(Forest/ EC 0.1316 0.2633 NS NS Broadcast

- Aerial

Ground (Broadcast,

Band, Direct Preplant,

Established

planting, Foliar

### Page 9 of 47 Shelterbelt) treatment

Crambe EC 0.2493 0.2493 1 NS Broadcast

- Aerial, Ground Foliar

Cranberry EC 0.251 0.505 2 NS Ground (Broadcast,

Spot treatment,

Wipe

- on/Wiper

treatment After bud break,

Dormant, Post

- bloom, Postharvest

Eucalyptus EC 0.1898 NS NS NS Broadcast

– Aerial.

Ground (Broadcast,

Band, Direct, Spot

treatment) Preplant,

Established

planting, Foliar

Forest

Plantings

(Reforestation

Program) (Tree

Farms, Tree

Plantation, etc) EC 0.189 0.378 NS NS Broadcast

– Aerial.

Ground (Broadcast,

Spot treatment) Preplant, Postplant

Golf Course

Turf S C, G 0.2519 0.2519 2 NS Broadcast

-

Ground Foliar , Weed

Postemergence

Grasses Grown

for Seed EC 0.5024 0.5024 NS NS Broadcast

– Aerial.

Ground (Broadcast,

Band, Spot treatment Established planting

SC 0.505 NS 2 21

Grass Forage /

Fodder / Hay EC 0.1883 NS NS NS Broadcast

–

Ground Fall

HOPS EC 0.251 0.251 NS NS Broadcast

– Ground, Spot

treatment Foliar

Meadowfoam EC 0.1913 0.1913 NS NS Broadcast

–

Ground Foliar

Mint /

Peppermint /

Spearmint EC 0.5024 NS NS NS Broadcast

–

Ground Spring, Fall

Mustard EC 0.2493 0.2493 NS NS Ground (Broadcast,

Spray treatment) Foliar

Nonagricultural

R ight

- of

- Way /

Fencerows /

Hedgerow s EC 0.2493 0.5024 NS NS Broadcast

– Aerial.

Ground (Broadcast,

Cut Stem, Foliar,

Spot, Stump, Tree

Injection, Girdle

treatments) Established

Plantings, Spring,

Postemergence,

Fall, When needed,

Foliar

Nonagricultural

Uncultivated

Areas / Soils EC 0.3797 0.3797 NS

NS Broadcast

– Aerial.

Ground (Broadcast,

Cut Stem, Foliar,

Spot, Stump, Tree

Injection, Tree

Wound, Frill, Girdle

treatments) Weed

Postemergence,

Foliar, When

needed SC 0.189 0.189 1

Oats EC 0.5238 0.5238 NS NS Broadcast

– Aerial.

Ground (Broadcast,

Band, Spot

treatment) Foliar

Ornamental

Herbaceous

Plants EC 0.5238 0.5238 NS NS Broadcast

– Ground,

Spray Foliar

Ornamental

Lawns and Turf G, EC, SC 0.3827 NS NS NS Broadcast

– Ground,

Spray, Spot treatment Foliar, Weed

Postemergence

Ornamental

Sod Farm

(Turf) EC 0.1330 0.5682 NS NS Broadcast

– Ground,

Spray, Spot treatment Foliar

Ornamental

(unspecified) EC 0.505 0.505 NS NS Broadcast

– Ground,

Spray, Spot treatment Foliar

Ornamental

Woody Shrubs

and Vines EC 0.505 0.505 NS NS Broadcast

– Ground,

Spray, Spot treatment Foliar

### Page 10 of 47 Pastures EC 0.505 0.505 NS

NS Broadcast

– Aerial.

Ground (Broadcast,

Cut Stem, Foliar,

Spot, Stump, Tree

Injection, Girdle

treatments Established

Plantings, Spring,

Weed

Postemergence,

Fall, When needed,

Foliar SC 0.505 0.505 1

Poplar (Forest /

Shelterbelt) EC 0.505 0.505 NS NS Broadcast

– Aerial.

Ground (Broadcast,

Band, Spot

treatment) Established

Plantings, Preplant,

Foliar

Radish EC 0.5238 0.5238 NS NS Broadcast

– Ground, Foliar

Rangelands EC 0.3827 NS NS

NS Broadcast

– Aerial.

Ground (Broadcast,

Cut Stem, Foliar,

Spot, Stump, Tree

Injection, Girdle

treatments Foliar

SC 0.2493 0.5024 2

Recreation

Area s EC 0.189 0.189 NS NS Broadcast

– Aerial.

Ground (Broadcast,

Cut Stem, Foliar,

Spot, Stump, Tree

Injection, Girdle

treatments Established

Plantings, Spring,

Postemergence,

Fall, When needed,

Foliar

Recreation

Area Lawns G 0.5238 0.5238 2 NS Broadcast

- Ground Foliar

Southern Pine

(Seed Orchard) EC 0.3827 NS NS NS Broadcast

– Ground,

Spot treatment Weed

Postemergence

Spearmint EC 0.5238 0.5238 NS NS Broadcast

- Ground Spring, Fall

Spinach EC 0.1884 NS NS NS Broadcast

- Ground Foliar

Stone Fruits EC 0.189 NS NS NS Broadcast

- Ground Foliar

Strawberry EC 0.3777 0.3777 NS NS Broadcast

– Ground,

Band, Spot treatment Established

Plantings, Spring,

Postharvest

Sugar Beet EC 0.189 0.189 NS NS Broadcast

– Aerial.

Ground (Band,

Broadcast treatment Foliar

Swamps /

Marshes /

Wetlands /

Stagnant

Water 2 EC 0.251 0.251 NS NS Broadcast

– Aerial.

Ground (Broadcast,

Cut Stem, Foliar,

Spot, Stump, Tree

Injection, Girdle

treatments Established

Plantings, Spring,

Postemergence,

Fall, When needed,

Foliar

Triticale EC 0.251 0.251 NS NS Broadcast

– Aerial.

Ground (Broadcast.

Spot treatment Foliar

Turnip

(Greens) EC 0.251 0.251 1 NS Broadcast

Foliar

Turnip (Root) EC 0.5238 0.5238 1 NS Broadcast Foliar

Wheat EC 0.1330 0.1330 NS NS Broadcast

– Aerial.

Ground (Broadcast.

Band, Spot treatment Foliar

SC 0.1898 NS 1 NS



### NS

- Not Specified

1 

### EC

- Emulsifiable Concentrate; G

- Granular; SC

- Soluble Concentrate/Liquid

2 

### Use is on non

- irrigation ditch banks, seasonally dry wetlands (such as flood plains, deltas, marshes, swamps, or

bogs) and transitional areas between upland and lowland sites. Use is permitted to the waters edge, but application

directly to water is prohibited. Precautions to minimize spray drift onto water are recommended.

### Page 11 of 47 Table 3 . Uses Site and Application Information for Clopyralid Triethanolamine (PC 117404)

Use Site Formulatio

n Type 1 Max. Rate

(lbs a.e ./Acre) Max. No. of

Applications

per Year Min.

Application

Interval Application

Methods Comments

Single Annual

Agricultural

Fallow /

Idleland

Conservation

Reserve EC 0.3244 NS NS NS Broadcast

- Aerial

and Ground Weed

p ost emergence

Commercial /

Industrial

Lawns G 0.1593 NS NS NS Broadcast

- Ground Foliar

Golf Course

Turf G 0.1593 NS NS NS Broadcast

- Ground Foliar

Nonagricultural

R ight

- of

- Way /

Fencerows /

Hedgerow s G 0.1593 NS NS NS Broadcast

- Ground Foliar

Nonagricultural

Uncultivated

Areas / Soils EC 0.3244

NS NS NS Broadcast

- Aerial Weed

p ost emergence

Foliar G 0.1593 Broadcast

- Ground

Ornamental

Lawns and Turf G 0.1593

NS NS NS Broadcast

- Ground Weed

p ost emergence

Foliar EC 0.1622

Pastures EC 0.3244 NS NS NS Broadcast

- Aerial

and Ground Weed

p ost emergence

Rangelands EC 0.3244 NS NS NS Broadcast

- Aerial

and Ground Weed

p ost emergence

Recreation

Area Lawns G 0.1593 NS NS NS Broadcast

- Ground Foliar



### NS

- Not Specified

1 

### EC

- Emulsifiable Concentrate; G

- Granular



### Table 4 . Uses Site and Application Information for Clopyralid Potassium (PC 117423)

Use Site Formulation

Type 1 Max. Rate

(lbs a.e ./Acre) Max. No. of

Applications

per Year Min.

Application

Interval Application

Methods Comments

Single Annual

Corn, Field DF 0.156 0.21 NS NS Broadcast

- Ground

Band treatment

Burndown treatment

Soil incorporated

treatment Preplant

Preemergence

Postemergence

Spike stage

Weed

p ost emergence

Corn, Silage DF 0.156 0.21 NS NS Broadcast

– Ground

Band treatment

Burndown treatment

Soil incorporated

treatment Preplant

Preemergence

Postemergence

Spike stage

Weed

p ost emergence



### NS

- Not Specified

1 

### DF

- Water Dispersable Granules (Dry Flowable)



## 4. CONCLUSIONS FROM PREVIOUS ASSESSMENTS

4.1. Ecological Risk Assessments

The Agency has conducted multiple ecological risk assessments for clopyralid that serve as a

basis for this problem formulation

, most recently a Section 3 new use assessment for apple, leafy

### Page 12 of 47 

## B rassica subgroup 5B, and rapeseed subgroup 20A at maximum application rates of 0.25, 0.187,

and 0.187 lb a.i./A, respectively (USEPA, 2012 b )

. A 2009 Section 3 new use assessment

evaluated the use of clopyralid on annual strawberries at an application rate of 0.1 88 lb a.i./A

, cranberries and bushberries at 0.25 lb a.i./A with 2 applications

, an d Swiss chard at 0.25 lb a.i./A

(USEPA 2009a)

. These assessments drew upon two 2001 clopyralid Section 3 new use

assessments for use on (1) flax, p erennial s trawbe rries, an d head/stem Brassica ( USEPA, 2001a )

, and (2) m ustard greens, c ranberries, ga rden b eets, t ur nips, spinach, and stone fruit ( USEPA,

2001b ) . The maximum application rate in these two assessments is 0.5 lb a.i./A. A 24(c)

assessment in 2009 evaluated an application rate increase to 0.088 lb a.i./A for clopyralid use on

flax in North Dakota ( U.S. EPA, 2009c ). This assessment included a spray drift analysis using

terrestrial and aquatic plant toxicity data from other picolinic acid herbic ide s.

Maximum estimated aquatic exposure concentrations modeled in PRZM

- EXAMS in a 2009

assessment for peak, 21

- day , and 60

- day exposures were 8.03, 7.56, and 6.80 μg/L , respectively

(USEPA, 2009a)

. Maximum estimated aquatic exposure concentrations model ed in GENEEC in

a 2001 assessment for acute and chronic exposures were 29.2 and 28.6 μg/L , respectively, from

use on stone fruit at 0.5 lb a.i./A (USEPA, 2001b). The only identified direct risk concern in

previous assessments was for terrestrial plants. The major ecological risk conclusions from these

assessments are summarized in Table 5

.

Table 5 . Summary of Risk Concerns Identified for Clopyralid in Previous Assessments

Birds Mammals Terr.

Plants Terr.

Inverts Fish Bioaccum

ulation Aquatic

Inverts Aquatic

Plants Groundwater

Contamination Persistence Degradates

of Concern



### No No Yes No No 1 

### No No 1 

### No Yes Yes No

1 

### No data were available for the assessment of risk to estuarine/marine invertebrates or fish.



## 4.2. Drinking Water Exposure Assessments

A drinking water exposure assessment for clopyralid was conducted in 2009 for the proposed

new use s on Swiss chard, Bushberry subgroup 13

- 07B and annual strawberry (USEPA, 2009d )

and updated in 2011 for the proposed new uses on apple, leafy B rassica subgrou p 5B, and

rapeseed subgroup 20A (USEPA, 2011)

. Maximum e stimated drinking water concentrations

(E DWCs ) in surface water were generated by the FIRST model and w ere based on a single

ground application of clopyralid at 0.5 lbs a.i./A for non

- food crops. Th e maximum EDWC s in

surface water for acute (1

- in

- 10

- year peak) and chronic (1

- in

- 10

- year average) exposure were 45

and 11.9 μg/L, respectively. The EDWC in groundwater was generated by the SCI

- GROW

model and was based on two ground application s of clopyralid at 0.25 lbs a.i./A with a 14 day

interval for bushberries. 2 

## The maximum modeled EDWC in groundwater was 0.39 μg/L

.

Maximum application rates listed in Section 3 include rates up to 0.66 lb a.i./A, higher than those

previously modeled in drinking water exposure assessments. Therefore, a new assessment will

be needed for registration review.

2 

### EDWCs in groundwater were previously modeled with SCI

- GROW for a single application at 0.5 lbs a.i./A,

however outdated input parameters resulted in a lower estimated groundwater concentration (USEPA, 2001a).

### Page 13 of 47 

## A search of the NAWQA database ( 11/25/2013 ) returned maximum detection level s for

clopyralid of 0.5288 ppb in surface water in Oregon and 0.42 ppb in groundwater in Washington.

Data provided by the Montana Department of Agriculture include maximum detection level s for

clopyralid of 0.8 00 ppb in surface water and 2.8 ppb in groundwater (Mulder, 2013)

. The

measured concentration s in groundwater are higher than the previously modeled concentration.

The residues of concern included in the calculations were the paren t compound only because the

aerobic soil metabolism study did not identify any major degradates, i.e. , no degradates were

formed at >10% of the applied dose. No aerobic aquatic metabolism data were available.

4.3. Clean Water Act Programs

Clopyralid i s not identified as a cause of impairment for any water bodies listed as impaired

under section 303(d) of the Clean Water Act. 3 

## No Total Maximum Daily Load (TMDL) criteria

have been developed for clopyralid

. 4 

## Aquatic benchmarks have been established for clopyr alid

and are available at http://www.epa.gov/oppefed1/ecorisk_ders/aquatic_life_benchmark.htm

. Any data submitted or otherwise located as part of the registration review pro cess may be used to

develop aquatic life benchmarks if applicable.

5. ENVIRONMENTAL FATE AND TRANSPORT

Clopyralid acid and three salts, clopyralid monoethanolamine, clopyralid triethanolamine, and

clopyralid potassium, are all registered with the Agency as active ingredients. The structures are

depicted in Table 6 below. The clopyralid salts are expected to quickly dissociate to clopyralid

acid in the environment.

Table 6

. Registered Active Ingredients Addressed in this Problem Formulation

Common Name PC Code CAS No. Molecular

Weight Structure

Clopyralid 117403 1702

- 17

- 6 192.00 g/mol

Clopyralid

monoethanolamine salt 117401 57754

- 85

- 5 252.07 g/mol

3 

### http://iaspub.epa.gov/tmdl_waters10/attai ns_nation_cy.cause_detail_303d?p_cause_group_id=885

4 

### http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_group_id=885&p_pollutant

_group_name=PESTICIDES

### Page 14 of 47 Clopyralid

triethanolamine 117404 119308

- 91

- 7 340.18 g/mol

Clopyralid potassium 117423 58509

- 83

- 4 230.00 g/mol



## Table 7 summarizes some chemical properties and environmental fate and transport

characteristics of clopyralid acid, the persistent form in the environment

. Environmental fate

data indicate that clopyralid is miscible in water (1 x 10 4 

## ppm) is stable to hydrolysis and

photolysis, and is very mobile in soil (K d 

## <0.1 in four soils). Clopyralid may be transported to

surface water via spray drift or by runoff occurring close to the time of applicatio n. Due to

anaerobic metabolism stability and high mobility, clopyralid is likely to persist in groundwater.

Aerobic metabolism is expected to be the primary pathway of degradation for clopyralid in the

environment, although no aerobic aquatic metabolism data are currently available. Clopyralid is

non

- volatile

, thereby limiting transport in air. The range of field dissipation half

- lives included

the single available aerobic soil metabolism half

- life.

Table 7 : Chemical Properties and Environmental Fate Characteristics of Clopyralid Acid

Parameter Valu e Description Source

(MRID)

Selected Physical/Chemical Parameters

Molecular Mass

(Molecular Formula) 192 C 6 

### H 3 

### Cl 2 

### NO 2 

### calculated

Vapor pressure

(2 5 °C) 1.26 x 10

- 6 

### mm Hg

-- 46912208

Aqueous solubility

(20 ° C) Miscible

-- 46912208

Henry’s Law Constant

(20°C) 3.81 x 10

- 11 

### atm

- m 3 

### /mole

-- calculated

Log octanol

- to

- water partition

coefficient (log K OW 

### ) - 1.81

-- Senseman, 2007

Acid dissociation constant (pKa) 2.3 3

-- Senseman, 2007

Persistence

Hydrolysis h alf

- life

(25±1 ° C) Stable

-- 4 2805701

Aqueous Photolysis h alf

- life

(25±1 ° C ) Stable pH 7 43891401

Soil Photolysis h alf life

(25±1 ° C) Stable S ilt loam 43891402

### Page 15 of 47 Parameter Valu e Description Source

(MRID)

Aerobic Soil Metabolism DT 50 

### (25±1°C) 12 .8 days S ilt loam 43891403

Anaerobic Aquatic Metabolism

D T 50 

### (25±1°C) Stable

-- 43891405

Mobility

Organic carbon

- normalized

Freundlich coefficients (K FOC 

### ) 4 .6 ml/g o.c. (mean) 12.90 (sand), 0.40 (clay

loam), 2.12 (silt loam),

and 3.15 (loam) 40095701

Field Dissipation

Terrestrial Field Dissipation DT 50 

### 10.7

– 25.2 days 10.7 days (NC, sand), 25.2

days (IL, silt loam), and

16.5 days (WI, silt loam)

Quantifiable residues

detected to depths of 46 cm

(NC) and 30 cm (IL, WI) 43891406



## Though aerobic aquatic metabolism is the anticipated primary route of degradation, it is currently

a data gap for this chemical. Modeling guidance assumes aerobic aquatic metabolism half

- life to

be double that of aerobic soil metabolism in the absence of data (USEPA, 2009b) . Although this

i s a conservative assumption, it should be noted that the primary route of degradation for this

chemical is not well

- characterized.

Aerobic soil metabolism data are required for three additional soils. In the absence of these

additional data, the single value will be multiplied by three for use as a modeling input, per the

current input parameter guidance (USEPA, 2009b).

Clopyralid has been found to persist through the composti ng process when contaminated yard

clippings are collected and composted ( Washington State University , 2005 ). The chemical

becomes concentrated in the final compost, which then may be toxic to plants to which it is

applied. Clopyralid’s behavior in compos t is a major uncertainty. Degradation and dissipation

processes differ in compost as compared to guideline environmental fate studies. An

environmental chemistry method and a compost dissipation study are needed to better

characterize this pathway. The absence of information on the persistence of clopyralid residues

in composted plant material or animal manure prohibits a quantitative assessment of the potential

risk to non

- target taxa posed by the application of composted material containing these resid ues.

5.1. Transformation Products

Table 8 s ummarizes the transformation products of clopyralid and their maximum amounts

formed by degradation pathway

. There are no major degradates, the only identified degradate is

carbon dioxide.

### Page 16 of 47 Table 8 : Clopyralid and Major Environmental Degradates

Chemical Name Chemical

Structure Study

Type Reference

(MRID) Maximum

Percent Recovery

( time period ) S tudy length

PARENT

Clopyralid (3,6

- dichloropyridine

2

- carboxylic

acid)

TRANSFORMATION PRODUCTS

Carbon Dioxide O=C=O Aerobic Soil

Metabolism 43891403 73.6%

(78 days) 78 days

Anaerobic Aquatic

Metabolism 43891405 2.8%

(365 days) 365 days

Photodegradation

Soil 43891402 2.9%

(30 days) 30 days

Nonextractable

or

Uncharacterized Aerobic Soil

Metabolism 43891403 20.7%

(43 days) 78 days

Anaerobic Aquatic

Metabolism 43891405 4.0%

(181 days) 365 days

Photodegradation

Soil 43891402 4.5%

(20 days) 30 days



## 6. RECEPTORS

Acute (short

- term) and chronic (long

- term) toxicity information is characterized based on

registrant

- submitted studies and a comprehensive review of the open literature on clopyralid

. Reported ecological incidents associated with clopyralid are also summarized below.

Table 9 and Table 10 provi de summaries of the aquatic and terrestrial taxonomic groups,

respectively, and surrogate species tested to characterize the potential acute and chronic

ecological effects of clopyralid acid

. Based on the available ecotoxicity information, clopyrali d

is p ractically non

- toxic to aquatic and terrestrial animals on an acute exposure basis . No chronic

toxicity data are available for aquatic organisms. Some chronic toxicity was observed in

mammals but no chronic effects were seen in birds . Aquatic and terres trial plant studies

demonstrate that clopyralid is toxic to plants, which is consistent with its use as an herbicide. No

toxic effects were seen in honey bees via oral or contact routes of exposure.

Acute toxicity studies were conducted with an end use product containing 35% clopyralid

monoethanolamine salt on freshwater fish (MRID 40151608 ) , freshwater invertebrates (MRID

40151608 ), birds (MRIDs 40151609 , 40151610, 40151611) , and honey bees (MRID 40151612 )

. In all cases, the toxicity endpoints (adjuste d for percent active ingredient) were equal to or higher

than the toxicity endpoints from the studies with clopyralid acid technical grade active ingredient

### Page 17 of 47 

## (TGAI). Therefore, using clopyralid acid toxicity data to assess risk to terrestrial and aquatic

a nimals is expected to be protective for uses of clopyralid salts as well. Toxicity differences

between the different forms of clopyralid to plants ha ve not been investigated.

6.1. Effects to Aquatic Organisms

Table 9 . Summary of Aqua tic Toxicity Studies for Clopyralid Acid

Taxonomic

Group Study

Type Surrogate Species Toxicity Value

( mg/L measured

active ingredient ) Acute

Toxicity

Classification Source

(MRID)

Freshwater

fish 1 

### Acute Rainbow t rout

( Oncorhynchus

mykiss ) LC 50 

### = 103.5 Practically

nontoxic 00139983

Bluegill sunfish

( Lepomis

macrochirus ) LC 50 

### = 125.4 Practically

nontoxic 00059969

Freshwater

invertebrates Acute Daphnia magna EC 50 

### = 233 Practically

nontoxic 00059972

Aquatic

plants and

algae Non

vascular Green a lgae

( Pseudokirchneriella

subcapitata ) EC 50 

### = 6.9 Moderately

toxic 40081402

1 

### Freshwater fish may be used as surrogates for aquatic

- phase amphibians.



## 6.2. Effects to Terrestrial Organisms

Table 10 . Summary of Terrestrial Toxicity Studies for Clopyralid Acid

Taxonomic

Group Study

Type Surrogate

Species Toxicity Value

(units in measured

active ingredient ) Acute

Toxicity

Classification Source

(MRID)

Birds 1 

### Acute Mallard d uck

( Anas

platyrhynchus ) LD 50 

### = 1465 mg/kg Slightly toxic 00059970

Sub

- acute

dietary Bobwhite

quail ( Colinus

virginianus ) LC 50 

### >4640 ppm Practically

nontoxic 00073640

Mallard d uck LC 50 

### >4640 ppm Practically

nontoxic 00073641

Chronic Mallard duck NOAEC / LOAEC =

1000 / >1000 ppm -- 00156001

Mammals Acute Oral Laboratory rat

( Rattus

norvegicus ) LD 50 

### >5000 mg/kg

- bw

(M &F ) Practically

nontoxic 41641301

Acute

Inhalation Laboratory rat LC50 > 1.0 mg/L Tox category

III 4184830 1

Chronic 2

-

gen Laboratory rat NOAE L / LOAE L =

500 / 1500 mg/kg

- bw /day

Endpoints: reduced body

weights in F 0 

### and F 1 

### NA 00138155

### Page 18 of 47 Taxonomic

Group Study

Type Surrogate

Species Toxicity Value

(units in measured

active ingredient ) Acute

Toxicity

Classification Source

(MRID)

Insects Acute

contact Honey bee

( Apis mellifera

L. ) LD 50 

### = >100 μg/bee Practically

nontoxic 00081595

Acute oral Honey bee LD 50 

### = > 100 μg/bee NA 00059971

Terrestrial

plants 2 

### Seedling

Emergence Monocot

–

onion NOAEC = 0.0037 lb ae /A

EC 25 

### = 0.038 lb ae /A

Endpoint: % emergence NA 40081401

Dicot

– soybean NOAEC = 0.0037 lb ae /A

EC 25 

### = 0.0046 lb ae /A

Endpoint: % emergence NA 40081401

Vegetative

Vigor Monocot

-

onion NOAEC = 0.0037 lb ae /A

EC 25 

### = >0.37 lb ae /A

Endpoint: 28

- d height NA 40081401

Dicot

– snap

bean NOAEC = 0.000075 lb

ae /A

EC 25 

### = 0.00038 lb ae /A

Endpoint: 28

- d height NA 40081401

NA: Not Applicable

1 

### Birds may be used as surrogates for terrestrial

- phase amphibians and reptiles.

2 

### The terrestrial plant study was conducted with an end use product containing 75% clopyralid potassium.



## The tier II seedling emergence and vegetative vigor terrestrial plant studies (MRID 40081401)

were re

- reviewed in 2012 ( USEPA, 2012a ). As noted in these reviews, the studies contain useful

data but are lacking crucial elements including weight measurements in the vegetative vigor

study and both weight and height measurements in th e seedling emergence study. Because of

these deficiencies, the studies are classified as supplemental and additional data are necessary to

adequately assess the risk of clopyralid use to non

- target terrestrial plants. Also, toxicity to

terrestrial plants may vary for clopyralid acid and the three registered clopyralid salts. Data on

formulations with each of these active ingredients would allow for this distinction. Terrestrial

plant data using co

- formulated TEPs wo uld additionally allow for assessment of synergistic

effects to plants, which have been observed for other picolinic acid herbicides (USEPA, 2013).

Results from t he avian reproduction study with the mallard duck (MRID 00156001 ) included

statistically sign ificant effects on normal hatchlings per eggs set and per eggs laid at the lowest

treatment concentration (100 ppm) and statistically significant effects on 14

- day old survivor

weight at the lowest and middle treatment concentrations (100 and 330 ppm). No effects were

seen at the highest treatment concentration (1000 ppm), and therefore these statistically

significant effects were not considered to be treatment related. This study is scientifically sound

and classified as acceptable. A low

- dose effect (h ormesis) is another possible explanation for the

study results. Reproduction data for an additional avian species may help to illuminate the

likelihood of this possibility.

### Page 19 of 47 

## 6.3. Ecological Incidents

Three databases were searched for ecological incidents poss ibly associated with clopyralid: the

Ecological Incident Information System (EIIS), the aggregate incident database, and t he Avian

Monitoring System (AIMS). The EIIS is an OPP database that houses ecological incidents that

have been reported to the Agency (USEPA, 2007 a ) . When available, EIIS includes date and

location of an incident, type and magnitude of effects observed in various species, use(s) of

pesticides known or suspected of contributing to the incident, and results of any chemical residue

analys is or other analyses conducted during incident investigation. EIIS incidents are

categorized according to the certainty that the incident resulted from pesticide exposure. The

AIMS database is administered by the American Bird Conservancy and contains pu blicly

available data on reported avian incidents involving pesticides. Many of the incidents listed in

this database are also in the EIIS. The aggregate incident reports provide counts of ecological

incidents considered “minor.” These are reported to t he Agency quarterly by registrants.

6.3.1. Ecological Incident Information System

EIIS returned 303 incidents

, all of which involved damage to terrestrial plants, including 21 8

attributed to clopyralid use (PC 117403), 18 attributed to clopyralid monoethanolamine salt (PC

117001), 1 attributed to clopyralid triethanolamine (PC 117404)

, and 66 attributed to clopyralid

potassium (PC 117423). In sum, 236 of the 303 incidents involved registered uses, 12 were

accidental misuses, 2 were intentional misuses, 7 were misuses with unknown intent, and 46

were of unknown uses. Certainty of attributing the incidents to clopyralid use was “highly

probabl e ” for 8 incidents, “probabl e ” for 132 incidents, “possible” for 1 55 incidents, and

“unlikely” for 8 incidents. Many of the incidents were attributable either to direct application of

a clopyralid product or to spray drift. See Appendix B

. EIIS Incidents for a list of all incidents

reported in EIIS through October 31, 2013

.

Three incidents provided information specific to use of compost with clopyralid residues:

1. Incident I010414

- 001 : Two complaints were received from the Washington State

Department of Agriculture regarding the damaging effects of compost from a regional

compost facility in 2000 . The problem was that grass clippings being comp osted had

traces of clopyralid (Confront) which were not degraded durin g the 60

- 90 day

composting period at the plant. When this compost material was used in the potting soil

of greenhouses, it had a detrimental effect on plants. With tomato plants, for example,

the symptoms we re cupping of leaves, slight bending or twistin g of stems, fiddleneck

appearance of new growth, and sometimes even accelerated growth. There is a warning

on the label saying that compost containing grass clippings that had been treated with

clopyralid should not be used in the growing season of applic ation.

2. Incident I011897

- 002 : Clopyralid was responsible for killing tomato plants that had been

grown in compost prepared by Washington State University , as reported in incident

I010414

- 001

. A report in the September, 2000, issue of BioCycle described th e

persistence of clopyralid in compost containing clippings from lawns that had been

treated with clopyralid. A product from the Washington State U. facility contained 100

-

### Page 20 of 47 

## 1300 ppb clopyralid after the passage of a year. A compost product from Spokane, W A,

had caused injury to tomato plants, and nine months later the residue ranged from 31 to

75 ppb. A new composting method was instituted in the fall of 2000 but in the following

March the concentration was measured at 57 to 67 ppb clopyralid. In May, an alyses

showed 73

- 80 ppb clopyralid.

3. Incident I012701

- 001 : A Columbus, OH, Compost Facility conducted a bioassay to

investigate the toxicity of their compost to tomato seedlings in 2002 . The seedlings

showed stunted growth and splitting of terminal leaves , which was attributed to

clopyralid and triclopyr exposure with “probable” certainty

.

The number of documented incidents in EIIS is believed to be a very small fraction of total

mortality caused by pesticides for a variety of reasons. Incident reports for non

- target organisms

typically provide information only on mortality events and plant damage. Sub

- lethal effects in

organisms such as abnormal behavior, reduced growth and/or impaired reproduction are rarely

reported, except for phytotoxic effects in terrestrial plants. An absence of reports does not

necessarily equate to an absence of incidents given the nature of the incident reporting.

6.3.2. Avian Monitoring System

AIMS identified one ecological incident involving clopyralid as of August 29, 2013. The

incident was “highly likely” attributed to pesticide exposure, which included both triclopyr and

clopyralid. Triclopyr and clopyralid have very similar acute and sub

- acute avian toxicity

endpoints. Three birds were killed, at least two of which were trumpeter swans. Chemical

residues were found in the carcasses and circumstances were “clearly indicative of poisoning.”

6.3.3. Aggregate Incident Database

In addition to the incidents recorded in EIIS, registrants have reported minor c lopyralid incidents

to the Agency in aggregate reports. Registrants reported 263 minor plant incidents, five minor

wildlife incidents and one other minor incident

. These numbers include reports filed under PC

codes 117401 (16 incidents), 117403 (150 inci dents), 117404 (one incident), and 117423 (102

incidents). Unless additional information on these aggregated incidents becomes available, they

will be assumed to be representative of registered uses of clopyralid in the risk assessment.

7. EXPOSURE PATHWAYS OF CONCERN

The environmental fate properties of clopyralid indicate that direct spray, spray drift, runoff, and

leaching represent potential transport mechanisms of th is chemical to aquatic and terrestrial

organisms. Drinking water and inhalation exposu re pathways were screened using the SIP

(Screening Imbibition Program ) and STIR (Screening Tool for Inhalation Risk) screening

methods (see Appendix A. SIP and STIR Results for details). Potential exposure pathways of

concern were found for clopyralid for drinking water but not for inhalation. SIP and STIR are

described in detail at: http://www.epa.gov/oppefed1/models/terrestrial/index.htm

.

### Page 21 of 47 

## Because clopyralid can leach into groundwater , there is a potential for adverse effects on

terrestrial plants when irrigated with a groundwater

- derived source, particularly in areas where

the soil is permeable and/or groundwater is shallow.

Clopyralid has been found to survive the composting process when yard clippings are collected

and composted

. The chemical becomes concentrated in the final compost, which then may be

toxic to plants to which it is applied.

8. ANALYSIS PLAN

8.1. Stressors of Concern

8.1.1. Ecological Risk Assessment

The stressor of ecological concern is the parent compound only. As described in Section 5.1 , no

major degradates are identified and among minor degradates only carbon dioxide (CO 2 

## ) is

identified.

8.1.2. Drinking Water Assessment

Previous drinking water assessments are based on tier 1 models (FIRST and SCI

- GROW) and no

longer reflect the maximum application rates for clopyralid

. T he drinking water assessments will

be re

- evaluated with tier 2 models (PE5 and PRZM

- GW) using the maximum application rates

listed in Section 3 to better reflect the potential exposure. Available monitoring data will also be

considered. The stressor of concern for drinking water is the parent compound only.

8.2. Measures of Exposure

EFED will use standard available models to evaluate potential exposures to aquatic and

terrestrial organisms as described at http://www.epa .gov/pesticides/science/models_db.htm

. Available monitoring data will also be considered.

Screening level calculations have suggested that the drinking water exposure pathway may be

significant for clopyralid for acute and chronic risk to terrestrial wildlife

. This pathway may be

further considered at t he time of the risk assessment

.

Estimated concentrations of mobile and persistent herbicides, such as clopyralid, in irrigation

water may be calculated to determine potential risk to irr igated crops. As detailed above, the

persistence, mobility, and solubility of clopyralid indicate the potential for the chemical to r each

ground and surface water.

Clopyralid has been found to survive the composting process when yard clippings are colle cted

and composted

. The chemical becomes concentrated in the final compost, which then may be

toxic to plants to which it is applied. Therefore, the exposure by this route will be addressed in

the risk assessment

.

### Page 22 of 47 

## Applications to individual trees can re sult in absorption and translocation of cl opyralid from the

site of application throughout the tree. Birds, mammals, and terrestrial invertebrates may be

exposed through ingestion of leaves, seeds, pollen, or other edible portions of the tree. Leaves

con taining cl opyralid may fall onto the ground or into water resulting in movement of cl opyralid

to soil and water. Finally, trees treated with cl opyralid may be used as compost. There is no

currently approved model for estimating potential exposure to orga nisms from tree injection, cut

stump treatment, hack and squirt method, and frill and girdle methods. A screening

- level

estimate of exposure will be completed for this assessment.

8.3. Measures of Effect

Toxi city data presented in Section 6 of this problem formulation will be used to calculate risk

quotients. Any additional information submitted by the registrant or fo und in the open literature

prior to conduct of the risk assessment will also be considered. The open literature studies are

identified using EPA’s ECOTOXicology database ( ECOTOX) (USEPA, 2007 b ), which employs

a literature search engine for locating chemic al toxicity data for aquatic life, terrestrial plants,

and wildlife. The evaluation of both sources of data can also provide insight into the direct and

indirect effects of pesticides on biotic communities from loss of species that are sensitive to the

ch emicals and from changes in structure and functional characteristics of the affected

communities.

8.4. Endangered Species Assessments

Consistent with the Agency’s responsibility under the Endangered Species Act (ESA), the

Agency will evaluate risks to federal ly threatened and/or endangered (listed) species from

registered uses of pesticides in registration review

. The process for evaluating potential risks to

listed species is further described at

http://www.epa.gov/oppfead1/endanger/litstatus/riskasses.htm

.

8.5. Endocrine Disruptor Screening Program

Clopyralid was included in neither the first group of 67 chemicals issued an order to conduct Tier

1 EDSP testing nor the second list of 109 chemicals

. For additional information the EDSP

program, visit http://www.epa.gov/endo/

.

9. PRELIMINARY IDENTIFICATION OF DATA GAPS

9.1. Environmental Fate

Table 11 i dentifies environmental fate studies by MRID that offer data for each guideline

requirement, as well as study classifications and whether or not further data are needed in orde r

to support risk assessment

.

### Page 23 of 47 Table 11 . Submitted Environmental Fate Data for Clopyralid

OCSPP

Guideline Data

Requirement Submitted

Studies

(MRID) Study

Classification Are additional

data needed to

conduct risk

assessment? Justification

835.2120 Hydrolysis 42805701 Acceptable No NA

835.2240 Aqueous

Photolysis 43891401 Acceptable No NA

835.2410 Soil Photolysis 43891402 Acceptable No NA

835.4100 Aerobic Soil

Metabolism 43891403 Supplemental Yes Only one soil tested; need a study of

three additional soils.

835.4300 Aerobic

Aquatic

Metabolism None NA Yes No data are available. Data are critical

for aquatic assessments. A study of

two water

- sediment systems is needed.

835.4400 Anaerobic

Aquatic

Metabolism 43891405 Acceptable No NA

835.1230/

835.1240 Adsorption/

Desorption and

Leaching 40095701 Acceptable No NA

835.6100 Terrestrial

Field Dissipation 43891406 Acceptable No NA

Non

guideline Dissipation in

Compost None NA Yes See justification below table.

850.6100 Analytical

Method in

Water None NA Yes No analytical methods have been

submitted for clopyralid. Methods and

independent laboratory validations

(ILV) for soil, water, and compost are

needed. LOQs should be less than

toxicological levels of concern.

Methods are requested that can be used

with equipment found in state labs and

that use standards that can be readily

obtained. Analytical

Method in Soil None NA Yes

Analytical

Method in

Compost None NA Yes



## Non

- guideline Study: Dissipation in Compost

. A study is requested to demonstrate the rates of

degradation and leaching in vegetative and manure composts. The study will be used to

characterize the risk from clopyralid residues in compost and may demonstrate potential

mitigations such as com post holding times. The absence of information on the persistence of

clopyralid residues in composted plant material or animal manure prohibits a quantitative

assessment of the potential risk to non

- target taxa posed by the application of composted material

containing these residues. A protocol is requested for review before the study is conducted.

Through the SFIREG Pesticides Operations & Management committee on September 16, 2013,

it was made known that Dow AgroSciences is developing a molecul ar imprinted polymer for

solid phase extraction that could be used for detecting clopyralid in compost. It was expected

that a n analytical method could be released to state laboratories by April 2014.

### Page 24 of 47 Guideline Number: N/A

Study Titles: Dissipation study in compost

Rationale for Requiring the Data

The application of clopyralid to vegetative matter that is subsequently used as compost or animal feed

has been found to retain clopyralid residues and affect non

- target plants. This route of exposure is

common across the picolin i c acid herbicides (aminopyralid, clopyralid, and picloram). A study is

requested to demonstrate the rates of degradation and leaching in vegetative and manure com posts.

Practical Utility of the Data

How will the data be used? Through the SFIREG Pesticides Operations & Management committee

on September 16, 2013, it was made known that Dow AgroSciences is developing a molecular

imprinted polymer for solid phase extraction that could be used for detecting a picolinic acid in

compost. It was expected that a method could b e released to state laboratories by April 2014. A

compost dissipation study would be instrumental in interpreting the monitoring data that will become

available after this method is disseminated.

How could the data impact the Agency’s future decision

- making? The study will be used to

characterize th e risk from clopyralid residues in compost and may demonstrate potential mitigation

measures, such as compost holding times.



## 9.2. Effects

Table 12 and Table 13 identify ecological effec ts studies by MRID that offer data for each

guideline requirement, as well as study classifications and whether or not further data are needed

in order to support risk assessment.

Table 12 . Submitted Aquatic Ecological Effects Data for Clopyralid

OCSPP

Guideline Data

Requirement Submitted

Studies

(MRID) Study

Classifications Are additional

data needed to

conduct risk

assessment? Justification

850.1010 Freshwater

invertebrate

acute toxicity 00059972 Acceptable No NA

850.1025

850.1035 Saltwater

invertebrate

acute toxicity None NA No Freshwater invertebrate acute

toxicity data indicate that

clopyralid is practically non

- toxic

to aquatic invertebrates. The LC 50



### is 5 orders of magnitude higher

than the highest EEC in previous

assessments. Acute toxicity data

for other picolinic acid herbicides

shows endpoints for freshwater

and saltwater invertebrates within

one order of magnitude.

850.1075 Freshwater fish

acute toxicity 0013 9983 Acceptable No NA

00059969 Acceptable No NA

### Page 25 of 47 OCSPP

Guideline Data

Requirement Submitted

Studies

(MRID) Study

Classifications Are additional

data needed to

conduct risk

assessment? Justification

850.1075 Saltwater fish

acute toxicity None NA No Freshwater fish acute toxicity

data indicate that clopyralid is

practically non

- toxic to aquatic

invertebrates. The LC 50 

### is 5

orders of magnitude higher than

the highest EEC in previous

assessments. Acute toxicity data

for other picolinic acid herbicides

shows endpoints for freshwater

and saltwater fish within one

order of magnitude.

850.1300 Freshwater

invertebrate

life cycle None NA Yes No d ata are available with which

to assess chronic risk to

freshwater invertebrates. Due to

clopyralid’s expected persistence

in aquatic systems, these data are

needed to determine if there is a

risk concern.

850.1350 Saltwater

invertebrates

life cycle None NA No If chronic aquatic toxicity is

determined to be a risk concern,

freshwater species data will be

used as a surrogate.

850.1400 Freshwater fish

early

- life stage None NA Yes No d ata are available with which

to assess chronic risk to

freshwater fish. Due to

clopyralid’s expected persistence

in aquatic systems, these data are

needed to determine if there is a

risk concern.

850.1400 Saltwater fish

early

- life stage None NA No If chronic aquatic toxicity is

determined to be a risk concern,

freshwater species data will be

used as a surrogate.

850.4400 Aquatic plant

growth: Tier II

vascular plants None NA Yes No d ata are available with which

to assess risk to vascular aquatic

plants.

850. 4 5 00

(previously

850.5400) Aquatic Plant

Growth: Tier II

algae 40081402 Acceptable Yes Toxicity data on two additional

species are needed. A

, freshwater

diatom and marine diatom are

recommended.

850.4550 Aquatic Plant

Growth:

Cyanobacteria None NA Yes Toxicity data on blue green algae

are needed as part of the aquatic

plant growth toxicity data set.

NA: Not Applicable

### Page 26 of 47 Table 13 . Submitted Terrestrial Ecological Effects Data for Clopyralid

OCSPP

Guideline Data

Requirement Submitted

Studies

(MRID) Study

Classifications Are data

needed for

risk

assessment? Justification and Assumptions

EPA will Make in Absence of

Data

850.2100 Avian oral

toxicity 00059970 Acceptable Yes Acute oral toxicity data are needed

for a passerine species. Clopyralid

may be more acutely toxic to

passerines than to the previously

tested species. An LD 50 

### only 10%

lower than the mallard duck LD 50



### would result in a risk concern for

listed species.

850.2200 Avian dietary

toxicity 00073640 Acceptable No NA

00073641 Acceptable

850.2300 Avian

reproduction 00156001 Acceptable Yes Avian reproduction data are

needed for an upland game species

( e.g. , b obwhite quail ). Chronic

exposure to clopyralid is a concern

due to its persistence. Additional

chronic toxicity data will help to

minimize uncertainty in the results

of the mallard duck study.

850.3020 Honey bee

acute contact

toxicity 00081595 Acc eptable No NA

Non

guideline Honey bee

acute oral

toxicity 00059971 Supplemental No NA

850.3030 Honey bee

residue on

foliage None NA No NA

850.3040 Field testing

for pollinators None NA No NA

850.4100 Terrestrial

plant toxicity:

S eedling

emergence 40081401 Supplemental Yes Guideline compliant Tier II

seedling emergence data are

needed for assessment of risk to

non

- target terrestrial plants. Data

are requested for four typical end

use products, one each containing

clopyralid, clopyralid

monoethanoloa mine salt,

clopyralid triethanolamine, and

clopyralid potassium.

### Page 27 of 47 OCSPP

Guideline Data

Requirement Submitted

Studies

(MRID) Study

Classifications Are data

needed for

risk

assessment? Justification and Assumptions

EPA will Make in Absence of

Data

850.4150 Terrestrial

plant toxicity:

V egetative

vigor 40081401 Supplemental Yes Guideline compliant Tier II

vegetative vigor data are needed

for assessment of risk to non

target terrestrial plants. Data are

requested for four typical end use

products, one each containing

clopyralid, clopyralid

monoethanoloamine salt,

clopyralid triethanolamine, and

clopyralid potassium.

Additionally, data for

representative TEPs co

- formulated

with other herbicides are

requested for the purpose of

evaluating synergism

. Studies

should provide justification for the

selection of the TEP used. TEP

studies can be limited to the most

sensitive crops from prior

clopyralid studies including onion,

snap bean, soybe an, sunflower,

tomato, and wheat.

### Page 28 of 47 

## 10. REFERENCES

Mulder, R. Personal communication. Montana Department of Agriculture. Dec. 30, 2013.

Senseman, S. S., ed. 2007. Herbicide Handbook. 9th ed. Lawrence, KS: Weed Science Society of

America

.

U.S. EPA. 2013. Problem Formulation for the Environmental Fate and Ecological Risk,

Endangered Species, and Drinking Water Assessments in Support of the Registration Review

of Picloram . PC Code: 005101, 005102, 005104; DP Barcode: 416059 . Dated December 3,

2013.

U.S. EPA. 2012a. Addendum to DERs for Seedling Emergence and Vegetative Vigor Studies

with Clopyralid . PC Code: 117403; DP Barcode : 398834 . Dated February 21, 2012.

U.S. EPA. 2012 b

. Ecological Risk Assessment for the Proposed Section 3 New Uses of

Clopyralid on Apple, Leafy Brassica Subgroup 5B, and Rapeseed Subgroup 20A. PC Code:

117403; DP Barcode : 394199, 391398 . Dated March 26, 2012.

U.S. EPA. 2011. Tier I Drinking Water Assessme nt for Proposed New Use of Clopyralid on

Apple, L eafy Brassica Greens Subgroup 5B, and Rapeseed Subgroup 20A, except Camelina

(Gold of Pleasure). PC Code: 117403; DP Barcode: 391398 . Dated December 19, 2011.

U.S. EPA. 2009a. Ecological Risk Assessment Add ressing the Proposed Registration of

Clopyralid for IR

- 4 New Uses on strawberries, Swiss chard, annual strawberry, blu eberry,

bushberry subgroup 13

- 07B. PC Code: 117403; DP Barcode: 364286, 361314

. Dated

October 30, 2009

.

USEPA. 2009b. Guidance for Selecting Input Parameters in Modeling the Environmental Fat e

and Transport of Pesticides. Version 2.1. U.S. Environmental Protection Agency, Office

of Pesticide Programs, Environmental Fate and Ef fects Division, Oct. 22, 2009. Available

at: http://www.epa.gov/oppefed1/models/water/input_parameter_guidance.htm

U.S. EPA. 2009 c

. Review of North Dakota 24(c) Application Rate Increase for Clopyralid on

Flax. PC Code: 117403; DP Barcode: 369950. Dated November 17, 2009.

U.S. EPA. 2009 d

. Tier I Drinking Water Assessment for Proposed New Use of Clopyralid on

Swiss Chard, Bushberry Subgroup 13

- 07B and Annual Strawberry

. PC Code: 117403; DP

Barcode 361314. Dated September 9, 2009.

U

. S

. EPA. 2007 a . Ecological Incident Information System.

http://www.epa.gov/espp/consultation/ecorisk

- overview.pdf

U

. S

. EPA. 2007 b . ECOTOXicology Database. Office of Research and Development National

Health and Environmental Effects Research Laboratory’s (NHEERL’s) Mid

- Continent

Ecology Division (MED). http://cfpub.epa.gov/ecotox/

### Page 29 of 47 

## U.S. EPA

. 2001a. IR

- 4 Request for the Use of Clopyralid in Flax, Perennial Strawberries, and

Head/Stem Brassica. PC Code: 117403; DP Barcodes: 270512, 271509, 270505 . Dated May

3, 2001

.

U.S. EPA. 2001b. IR

- 4 Registrations of Clopyralid in Mustard Greens, Cranberri es, Garden

Beets, Turnips, Spinach, and Stone fruit. PC Code: 117401/117403; DP Barcode: 278288,

278292, 278295, 278297, 278301, 278307 . Dated December 13, 2001

.

Washington State University. 2005. Clopyralid in Compost . Accessed October 18, 2013.

Available at: http://puyallup.wsu.edu/soilmgmt/Pubs/Paper_ClopyralidQandAv10.pdf

MRID Citation

Environmental Fate Studies

40095701 Woodbrun, K.B. and B.W. French. 1987. A Soil Sorption/Desoption Study of Clopyralid. Ag.

Chemistry R and D Laboratories, Dow Chemical U.S.A., Midland, MI.

42805701 Woodburn, K.B. 1987. Clopyralid

- The Hydrolysis of Clopyralid in Sterile, Buffered Water.

Laboratory Study ID: LEH060893. Study performed and submitted by Dow Chemical U.S.A.,

Midland, MI.

43891401 Concha, M. and K. Shepler. 1994. Photodegradati on of [14C]clopyralid in buffered aqueous

solution at pH 7 by natural sunlight. Laboratory Project ID: 451W.

43891402 Concha, M., K. Shepler, and F. Batzer. 1994. Photodegradation of [ 14 

### C]clopyralid in/on soil by

natural sunlight. Laboratory Project ID: 454W. Unpublished study performed by PTRL West,

Inc., Richmond, CA; and submitted by DowElanco, Indianapolis, IN.

43891403 Skinner, W., N. Jao, and J. Smith. 1995. Aerobic soil metabolism of [ 14 

### C]clopyralid. Laboratory

Study ID: PTRL Report No. 4 41W

- 1. DowElanco Protocol ENV 93125.

43891404 Smith. J.K, S. Erhardt

- Zabik, and K.D. Schnelle. 1985. Effects of temperature, moisture and soil

on the soil metabolism and partitioning of [ 14 

### C]clopyralid. Laboratory Study ID: ENV 93118.

Dow Chemical U .S.A., Midland, MI.

43891405 Hawes, K. F. and S. Erhardt

- Zabik. 1995. The anaerobic aquatic metabolism of clopyralid.

Laboratory Study ID: ENV93076. Unpublished study performed and submitted by DowElanco,

Indianapolis, IN.

43891406 Roberts, D. W., A. M. Phillips, B. A. Blakeslee, and M. E. Swanson. 1995. Terrestrial dissipation

of clopyralid. Laboratory Study ID: ENV94020.

46912208 Baker, S. (2006) Product Chemistry Data for Colt + Sword. Project Number: 06/6124/5323.

Unpublished study prepared by Loveland Products, Inc. 15 p.

Ecological Effects Studies

00059969 Batchelder, T.L. (1974) Pollutional Evaluation of Dowco 290 (Picolinic acid: 3,6

- Dichloro).

(Unpublished study received Nov 12, 1980 under 464

- 563; submitted by Dow Chemical U.S.A.,

Midland, Mich.; CDL:099724

- B)

00059970 Fink, R.; Beavers, J.B.; Brown, R.; et al. (1980) Final Report: Acute Oral LD50

-- Mallard Duck:

Project No. 103

- 200. (Unpublished study received Nov 12, 1980 under 464

- 563; prepared by

Wildlife International, Ltd. in cooperation with Washington College, submitted by Dow Chemical

U.S.A., Midland, Mich.; CDL: 099724

- E)

00059971 Cole, J.H. (1974) The Acute Contact and Oral Toxicity to Worker Honey Bees of Technical

Dowco 290: DWC246/74726. (Unpubl ished study received Nov 12, 1980 under 464

- 563;

prepared by Huntingdon Research Centre, England, submitted by Dow Chemical U.S.A., Midland,

Mich.; CDL:099724

- F)

00059972 Batchelder, T.L. (1980) Toxicity of Dowco 290, a Herbicide, to Freshwater Invertebrate

Organisms: ES

- 392. (Unpublished study received Nov 12, 1980 under 464

- 563; submitted by Dow

Chemical U.S.A., Midland, Mich.; CDL:099724

- G)

### Page 30 of 47 MRID Citation

00073640 Fink, R. (1973) Final Report: Eight

- Day Dietary LC50

-- Bobwhite Quail: Dowco 290: Project No.

1 03

- 103. (Unpublished study received Nov 12, 1980 under 464

- 563; prepared by Truslow Farms,

Inc., submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:099724

- C)

00073641 Fink, R. (1973) Final Report: Eight

- Day Dietary LC50

-- Mallard Ducks: Dowco 290: Proje ct No.

103

- 104. (Unpublished study received Nov 12, 1980 under 464

- 563; prepared by Truslow Farms,

Inc., submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:099724

- D)

00081595 Cole, J.H. (1974) The Acute Contact and Oral Toxicity to Worker Honey Bees of Technical

Dowco 290: DWC246/74726. (Unpublished study received Jul 30, 1979 under 464

- EX

- 55;

prepared by Hunt

- ingdon Research Centre, England, submitted by Dow Chemical U.S.A.,

Midland, Mich.; CDL:098875

- I)

00138155 Dietz, F.; Mensik, D.; Rachunek, B.; et al. (1983) Dowco 290: Two Generation Dietary

Reproduction Study in Fischer

- 344 Rats. (Un

- published study received Jan 11, 1984 under 464

- 563; submitted by Dow Chemical U.S.A., Midland, MI; CDL:072287

- A)

00139983 Batchelder, T. (1974) Pollutional Evaluation of Dowco 290 (Picolinic Acid: 3,6

- Dichloro).

(Unpublished study received Dec 21, 1978 under 464

- EX

- 55; submitted by Dow Chemical

U.S.A., Midland, MI; CDL:236656

- G)

00156001 Beavers, J. (1985) Lontrel Herbicide: A One

- generation Reproduction Stu dy with the Mallard

(Anas platyrhynchos): Final Report: Project No. 103

- 235. Unpublished study prepared by Wildlife

Inter

- national Ltd. 99 p.

40081401 Weseloh, J. (1987) A Summary of Three Greenhouse Trials To Deter

- mine the Effects of

Clopyralid , 3,6

- D ichloro

- 2

- pyridinecarbo xylic Acid, on Seed Germination, Seedling Emergence,

and Vegeta

- tive Vigor of Six Dicotyledonae and Four Monocotyledonae Crop Cultivars.

Unpublished study prepared by Dow Chemical U.S.A. 158 p.

40081402 Dill, D.; Milazzo, D. (1985) Evaluation of the Toxicity of Lontrel T Herbicide to the Green Alga,

Selenastrum capricornutum Printz: ES

- 746. Unpublished study prepared by Dow Chemical U.S.A.

16 p.

40151608 Dill, D.; Milazzo, D.; Bartlett, E. (1986) Evaluation of the Toxi city of Lontr el 35A Herbicide

Concentrate to Representative Aquatic Organisms: ES

- 895. Unpublished study prepared by Dow

Chemical Co. 16 p.

40151609 Hinken, C.; Grimes, J.; Jaber, M. (1986) Lontrel 35A Herbicide Con centrate: An Acute Oral

Toxicity Study with the Mallard: Project No.: 103

- 252. Unpublished stud y prepared by Wildlife

Interna tional Ltd. 18 p.

40151610 Grimes, J.; Jaber, M. (1986) Lontrel 35A Herbicide Concentrate: A Dietary LC50 Study with the

Mallard: Project No.: 103

- 261. Un

- published study prepar ed by Wildlife International Ltd. 17 p.

40151611 Hinken, C.; Grimes, J.; Jaber, M. (1 986) Lontrel 35A Herbicide Con centrate: A Dietary LC50

Study with the Bobwhite: Project No.: 103

- 260. Unpublished study prepared by Wildlife

International Ltd. 17 p.

401 51612 Hinken, C.; Dingledine, J.; Jaber, M. (1986) Lontrel 35A Herbicide Concentrate: An Acute

Contact Toxicity Study with the Honey Bee: Project No.: 103

- 256. Unpublished study prepared by

Wildlife International Ltd. 15 p.

41641301 Jeffrey, M.; Schuetz, D.; Johnson, K. (1987) Lontrel T Herbicidal Chemical (Penta Process):

Acute Oral Toxicity Study in Fischer 344 Rats: Lab Project Number: K

- 038252

- 033A.

Unpublished study prepared by The Dow Chemical Co. 15 p.

4184830 1 Nitscke, K.; Crissman, J. (1991) Lontrel T: Acute Inhalation Toxicity Study with Fischer 344

Rats: Lab Project Number: K

- 0038252

- 045. Unpublished study prepared by DowElanco. 33 p.

### Page 31 of 47 

## Appendix A. SIP and STIR Results

SIP

The Screening Imbibition Program (SIP version 1.0; 6/15/2010) wa s used to calculate an upper

bound estimate of exposure via drinking w ater using the solubility of clopyralid ( 143,000 mg/L

, pesticide properties database ). The most sensitive acute and chronic avian toxicity endpoints

( mallard duck LD 50 

## = 1465 mg/kg

- bw and NOAEC = 1000 mg/kg

- diet, respectively) and the

most sensitive acute and chronic mammalian toxicity endpoints (rat, LD 50 

## >50 00 mg/kg

- bw and

NOAEL = 500 mg/kg

- bw/day, respectively) for clopyralid were used. The non

- definitive acute

oral endpoi nt results in a conservative estimate of toxicity here. Drinking water exposure to

clopyralid was determined to be a pathway of concern for both avian and mammalian species

(LOC exceedances are expected). Results are presented in the tables below

.

SIP Avian Results for Clopyralid

Parameter Acute Chronic

Upper bound exposure (mg/kg

- bw) 115830 115830

Adjusted toxicity value (mg/kg

- bw) 761 49.6

Ratio of exposure to toxicity 152 2335

Conclusion* Exposure through drinking

water alone is a potential

concern for birds Exposure through drinking

water alone is a potential

concern for birds



### SIP Mammalian Results for Clopyralid

Parameter Acute Chronic

Upper bound exposure (mg/kg

- bw) 24596 24596

Adjusted toxicity value (mg/kg

- bw) 3846 385

Ratio of exposure to acute toxicity 6.40 64.0

Conclusion* Exposure through drinking

water alone is a potential

concern for mammals Exposure through drinking

water alone is a potential

concern for mammals

*Conclusions are for drinking water exposure alone. This does not combine all routes of exposure. Therefore, when

aggregated with other routes ( i.e. , diet, inhalation, dermal), pesticide exposure through drinking water may

contribute to a total exposure that has potential for effects to non

- target animals.



## STI R

The Screening Tool for Inhalation Risk (STIR version 1.0; 11/23/2010) was used to calculate

upper bound estimates of clopyralid exposures via inhalation. The exposure pathways assessed

include both droplet inhalation and vapor phase inhalation. Model i nputs for clopyralid included

molecular weight (192 g/mole), vapor pressure (1.26 x10

- 6 

## mmHg ), highest application rate ( 0.5

lb a.i. /A), most sensitive acute avian toxicity endpoint ( mallard duck , LD 50 

## = 1465 mg/kg

- bw),

and most sensitive acute oral and inhalation mammalian toxicity endpoints (rat, LD 50 

## >5000

mg/kg

- bw and 4 hr inhalation LC 50 

## > 1 mg/L, respectively). The non

- definitive acute oral and

inhalation endpoint s result in conservative estimate s of toxicity here. Neither droplet nor vapor

inhalat ion were determined to be potential pathways of concern for avian or mammalian species.

STIR Avian (0.020 kg) Results for Clopyralid

Maximum Vapor Concentration in Air at Saturation (mg/m 3 

### ) 1.30E

- 02

Maximum 1

- hour Vapor Inhalation Dose (mg/kg) 1.64E

- 03

### Page 32 of 47 Adjusted Inhalation LD 50 

### 1.18E+00

Ratio of Vapor Dose to Adjusted Inhalation LD 50 

### 1.39E

- 03 Exposure not Likely Significant

Maximum Post

- treatment Spray Inhalation Dose (mg/kg) 4.80E

- 02

Ratio of Droplet Inhalation Dose to Adjusted Inhalation LD 50 

### 4.08E

- 02 Exposure not Likely Significant



### STIR Mammalian (0.15 kg) Results for Clopyralid

Maximum Vapor Concentration in Air at Saturation (mg/m 3 

### ) 1.30E

- 02

Maximum 1

- hour Vapor Inhalation Dose (mg/kg) 2.06E

- 03

Adjusted Inhalation LD 50 

### 5.95E+01

Ratio of Vapor Dose to Adjusted Inhalation LD 50 

### 3.46E

- 05 Exposure not Likely Significant

Maximum Post

- treatment Spray Inhalation Dose (mg/kg) 6.04E

- 02

Ratio of Droplet Inhalation Dose to Adjusted Inhalation LD 50 

### 1.01E

- 03 Exposure not Likely Significant

### Page 33 of 47 

## Appendix B

. EIIS Incidents

Table B

- 1. Incidents in the EIIS for PC 117401: Clopyralid monoethanolamine salt as of 10/31/13

Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total Magnitude Appl. Rate Appl. Method Formulation 3 Product

PLANTS I006199

- 001 Sugar beet RU 3 ND Unknown N/R Stinger

PLANTS I006199

- 002 Peppermint RU 3 OR Unknown N/R Stinger

PLANTS I006445

- 003 Corn RU 3 IA Unknown N/R N/R F Hornet

PLANTS I007739

- 001 Soybean 5/15/98 M A 3 MN L yon 120 acres 5.66 oz / acre Broadcast , ground N/R Stinger

PLANTS I012726

- 001 Corn 5/15/01 RU 3 MN C arver 103.5 acres 3 oz/acre Broadcast , ground Hornet

PLANTS I012726

- 002 Corn, field 5/2/01 RU 3 IL Cass 141 acres 3 oz/acre Broadcast , ground G Hornet

PLANTS I012726

- 003 Corn, field 4/18/01 RU 3 IL C hristian 60 acres of 120 3 oz/acre Broadcast , ground G Hornet

PLANTS I015748

- 016 Corn, field 5/29/04 RU 2 OH Defiance 132 acres 1 qt/acre Broadcast , ground EC Curtail

PLANTS I015748

- 017 Wheat 6/6/04 RU 3 MT Richland 36 acres Spray EC Stinger

PLANTS I015748

- 033 Corn, field 5/3/04 RU 2 IA Linn 520 acres affected 3.3 qts/acre N/R G Hornet

PLANTS I015748

- 040 Corn, field 6/1/04 RU 3 MO Carroll 62 acres 3 oz/acre d ry N/R G Hornet

PLANTS I015748

- 048 Corn, field 5/5/04 RU 3 IN Marshall 406 acres 3.3 qts/acre G Hornet

PLANTS I015748

- 049 Corn, field 5/5/04 RU 3 IN Pulaski 146 acres 3.3 qts/acre Spray G Hornet

PLANTS I015748

- 051 Corn, field 5/16/04 RU 3 IN Porter 70 acres affected 2.65 qts/acre G Hornet

PLANTS I016312

- 001 Forest 4/1/05 UN 2 OR Benton 300 acres 8 oz/acre Spray , air EC Transline

PLANTS I016927

- 001 Corn, field 8/24/05 RU 1 MN Clay 179 acres field corn 15 oz/acre Spray , ground EC WideM atch

PLANTS I023574

- 025 Corn 6/8/10 UN 2 NE Chase 260 acre 1 pt/acre

( product) Broadcast , ground Wide M atch

PLANTS I023574

- 052 Agricultural

area 5/25/10 UN 2 IN Putnam 100% of 28 acres 2 pt Broadcast , ground EC Sure Start

Herb



### Abbreviations: Appl.=Application; N/R=Not Recorded

1 

### Legality Code: RU=Registered Use, M=Misuse, MA=Misuse (Accidental), MI=Misuse (Intentional), U N =Unknown

2 

### Certainty Code: 0=Unrelated, 1=Unlikely, 2=Possible, 3=Probable, 4=Highly Probabl e. N/R=Not Reported

3 

### Formulation Code: DF=Dry Flowable; EC=Emulsifiable Concentrate; F= Flowable; G=Granular; WDG=Water Dispersable Granule; WP=Wettable Powder

### Page 34 of 47 

## Table B

- 2. Incidents in the EIIS for PC 117403: Clopyralid as of 10/31/13

Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total

Magnitude Appl. Rate Appl. Method Formul

ation 3 Product

PLANTS I003104

- 001 Agricultural

a rea 1/1/96 RU 4 ID All N/R N/R N/R Curtail

PLANTS I003138

- 001 Switch grass RU 3 MN Unknown Curtail

PLANTS I003151

- 001 Corn 1/1/96 RU 3 MN All N/R N/R N/R Scorpion III

PLANTS I004816

- 001 Soybean 1/1/97 RU 3 IA All N/R N/R N/R Stinger

PLANTS I004848

- 001 Agricultural

a rea 1/1/96 RU 3 IL All N/R N/R N/R Scorpion III

PLANTS I006214

- 001 Corn 11/3/97 RU 3 MN Unknown N/R N/R N/R Scorpion

PLANTS I006214

- 002 Corn 11/3/97 RU 3 IA Unknown N/R N/R N/R Scorpion

PLANTS I006214

- 003 Corn 11/3/97 RU 3 IA Unknown N/R N/R N/R Scorpion

PLANTS I006214

- 004 Soybean 11/3/97 RU 3 IL Unknown N/R N/R N/R Scorpion

PLANTS I006214

- 005 Corn 11/3/97 RU 3 IA Unknown N/R N/R N/R Scorpion

PLANTS I006214

- 006 Corn 11/3/97 RU 3 IA Unknown N/R N/R N/R Scorpion

PLANTS I006214

- 007 Corn 11/3/97 RU 3 IL Unknown N/R N/R N/R Scorpion

PLANTS I006214

- 008 Corn 11/3/97 RU 3 IA Unknown N/R N/R N/R Scorpion

PLANTS I006214

- 009 Corn 11/3/97 RU 3 MN Unknown N/R N/R N/R Scorpion

PLANTS I006214

- 010 Corn 11/3/97 RU 3 MN Unknown N/R N/R N/R Scorpion

PLANTS I006214

- 011 Corn 11/3/97 RU 3 MN Unknown N/R N/R N/R Scorpion

PLANTS I006214

- 012 Soybean 11/3/97 RU 3 IL Unknown N/R N/R N/R Scorpion

PLANTS I006442

- 001 Corn 1/1/98 RU 3 WI All N/R N/R N/R Scorpion III

PLANTS I006442

- 002 Corn 1/1/98 RU 3 NE All N/R N/R N/R Scorpion III

PLANTS I006442

- 003 Corn 1/1/98 RU 3 IL All N/R N/R N/R Scorpion III

PLANTS I006445

- 001 Corn RU 3 NE Unknown N/R N/R F Hornet

PLANTS I006445

- 002 Corn RU 3 IL Unknown N/R N/R F Hornet

PLANTS I006445

- 004 Corn RU 3 IA Unknown N/R N/R F Hornet

PLANTS I006445

- 005 Corn RU 3 WI Unknown N/R N/R F Hornet

### Page 35 of 47 Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total

Magnitude Appl. Rate Appl. Method Formul

ation 3 Product

PLANTS I006848

- 001 Agricultural

a rea 1/1/98 RU 3 MI All N/R N/R N/R Hornet

PLANTS I006848

- 002 Agricultural

a rea 1/1/98 RU 3 IA All N/R N/R N/R Hornet

PLANTS I006848

- 003 Agricultural

a rea 1/1/98 RU 3 IA All N/R N/R N/R Hornet

PLANTS I007251

- 001 Agricultural

a rea 1/1/98 RU 3 WI All N/R N/R N/R Scorpion III

PLANTS I007259

- 001 C orn 1/1/98 RU 2 WI Unknown U nknown N/R Hornet

PLANTS I007259

- 002 C orn 1/1/98 RU 2 WI Unknown N/R U nknown N/R Hornet

PLANTS I007259

- 003 C orn 1/1/98 RU 2 WI Unknown U nknown N/R Hornet

PLANTS I007259

- 004 C orn 1/1/98 RU 2 WI Unknown U nknown N/R Hornet

PLANTS I007702

- 001 C orn 8/9/98 UN 2 IN H enry 100 of 100

acres 3.2 oz/acre Broadcast , ground Hornet

PLANTS I007702

- 002 C orn 8/9/98 UN 2 IN D elaware All 100

acres 2.40 oz/acre Broadcast , ground Hornet

PLANTS I007702

- 003 C orn 8/9/98 UN 2 IN M adison All 40

acres 4.0 oz/acre Broadcast , ground Hornet

PLANTS I007702

- 004 C orn 8/9/98 UN 2 IN T ipton 50 of 100

acres 2.80 oz/acre Broadcast , ground Hornet

PLANTS I007702

- 005 C orn 8/9/98 UN 2 IN H amilton 30 of 60

acres 3.2 oz/acre Broadcast , ground Hornet

PLANTS I007702

- 006 C orn 8/5/98 UN 2 IL Iroquois All 25

acres 3.0 oz/acre Broadcast , ground Hornet

PLANTS I007702

- 007 C orn 8/4/98 UN 2 IL F ord All 10

acres 4.0 oz/acre Broadcast , ground Hornet

PLANTS I007702

- 008 C orn 8/4/98 UN 2 IL Ford All 10

acres 4.0 oz/acre Broadcast , ground Hornet

PLANTS I007702

- 009 C orn 8/10/98 UN 2 IN M adison All 60

acres 3.2 oz/acre Broadcast , ground Hornet

PLANTS I007702

- 010 C orn 8/18/98 UN 2 NE P ierce All 70

acres 3.2 oz/acre Broadcast , ground Hornet

PLANTS I007702

- 011 C orn 8/12/98 UN 2 IL D ouglas All 80

acres 2.4 oz/acre Broadcast , ground Hornet

PLANTS I007702

- 012 C orn 8/25/98 UN 2 WI C hippewa All 3 acres 2.4 oz/acre Broadcast , ground Hornet

### Page 36 of 47 Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total

Magnitude Appl. Rate Appl. Method Formul

ation 3 Product

PLANTS I007702

- 013 Corn 7/19/98 UN 2 IL Vermilion 18 rows 2.4 oz/acre Band Hornet

PLANTS I007702

- 014 C orn 7/20/98 UN 2 IL Vermilion Unknown 2.4 oz/acre Broadcast , ground Hornet

PLANTS I007714

- 001 Agricultural

a rea 5/24/98 RU 3 IL W arren 20

- 30% of

plants 4.0 oz/acre Broadcast , ground N/R Scorpion III

PLANTS I007750

- 001 Corn 5/1/98 RU 3 ND R ichland 60 acres 2 pts / acre Broadcast , ground N/R Curtail

PLANTS I007754

- 001 Agricultural

a rea 5/1

-

6/22/98 RU 3 IL L ee 56 plants 4.00 oz/acre Broadcast , ground N/R Scorpion III

PLANTS I007754

- 003 Agricultural

ar ea 4/28

-

6/10 /98 RU 2 MN G oodhue 80 acres 2.40 oz/acre Broadcast , ground N/R Hornet

PLANTS I007755

- 001 C orn 4/30/98 RU 2 WI B uffalo 67 acres 2.87 oz/acre Broadcast , ground N/R Hornet

PLANTS I007755

- 002 C orn 4/30

-

6/3 /98 RU 1 MN S teele 155 acres 2.40 oz/acre Broadcast , ground N/R Hornet

PLANTS I007755

- 003 Corn 5/1/98 RU 2 MN Steele 88 acres 2.40 oz/acre Broadcast , ground N/R Hornet

PLANTS I007755

- 004 Corn 4/30/98 RU 2 WI Pierce 230 acres 3.20 oz/acre Soil incorporation N/R Hornet

PLANTS I007755

- 005 C orn 5/1

-

6/24 /98 RU 2 MN 40 acres 3.20 oz/acre Broadcast , ground N/R Hornet

PLANTS I007755

- 006 Agricultural

a rea 5/5/98 RU 2 WI D unn 180 acres 2.40 oz/acre Broadcast , ground N/R Hornet

PLANTS I007755

- 007 C orn 5/5/98 RU 2 IA B oone 200 acres 2.00 oz/acre Broadcast , ground N/R Hornet

PLANTS I007755

- 008 C orn 5/3/98 RU 2 IA S tory 500 acres 2 oz/acre Broadcast , ground N/R Hornet

PLANTS I007755

- 009 Corn 5/2/98 RU 2 MN Renville 33 acres 2.4 oz/acre N/R N/R Hornet

PLANTS I007755

- 010 C orn 5/18/98 RU 2 IL M acoupin 5 acres 2.40 oz/acre Broadcast , ground N/R Hornet

PLANTS I007755

- 011 C orn 4/23/98 RU 1 IL M acoupin 70 acres 2.40 oz/acre Broadcast , ground N/R Hornet

PLANTS I007755

- 013 Corn 4/25/98 RU 2 IL M acoupin 90 acres 2.40 oz/acre Broadcast , ground N/R Hornet

PLANTS I007867

- 001 Agricultural

a rea 5/11/98 RU 3 IA S helby All 2.40 oz/acre Broadcast , ground N/R Hornet

PLANTS I007867

- 002 Agricultural

a rea 5/31/98 RU 2 MN I santi 40 acres 2.40 oz/acre Broadcast , ground N/R Hornet

PLANTS I007867

- 003 Agricultural

a rea 4/25/98 RU 2 IA C ass 40 Acres 4.00 oz/acre Broadcast , ground N/R Hornet

PLANTS I007867

- 004 Agricultural

a rea 5/2/98 RU 2 IA B remer 21 acres 2.00 oz/acre Broadcast , ground N/R Hornet

### Page 37 of 47 Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total

Magnitude Appl. Rate Appl. Method Formul

ation 3 Product

PLANTS I007874

- 001 Alfalfa 4/4/98 RU 3 WA G rant 300 acres N/R Broadcast , ground N/R Stinger

PLANTS I008002

- 001 C orn 10/11/98 UN 2 IA C alhoun 80 acres 2.0 oz/acre Broadcast , ground Hornet

PLANTS I008002

- 002 C orn 10/12/98 RU 2 IA C arroll All 330

acres 2.0 oz/acre Broadcast , ground Hornet

PLANTS I008002

- 003 C orn 10/13/98 RU 2 IA G rundy All 2400

acres 2.0 oz/acre Broadcast , ground Hornet

PLANTS I008002

- 004 C orn 9/30/98 RU 2 WI B uffalo All 655

acres 2.4 oz/acre Broadcast , ground Hornet

PLANTS I008002

- 005 C orn 10/15/98 RU 2 IL T azewell All 37.8

acres 2.4 oz/acre Broadcast , ground Hornet

PLANTS I008002

- 006 C orn 8/16/98 RU 2 IN B enton All 160

acres 2.4 oz/acre Broadcast , ground Hornet

PLANTS I008010

- 001 C orn 10/12/98 RU 2 IA C erro G ordo 25 of 213

acres 2.4 oz/acre Broadcast , ground Hornet

PLANTS I008010

- 002 Corn 10/14/98 RU 2 NE York 80 acres of

1200 1.2 oz/acre Band Hornet

PLANTS I008079

- 001 C orn 5/7/98 RU 2 IA D ubuque 120 acres 2.00 oz/acre Broadcast , ground N/R Hornet

PLANTS I008079

- 002 C orn 4/30/98 RU 2 IA J asper 300 acres 2.40 oz/acre Broadcast , ground N/R Hornet

PLANTS I008079

- 003 C orn 5/5/98 RU 2 IA M onona 160 acres 2.4 oz/acre Broadcast , air N/R Hornet

PLANTS I008079

- 004 C orn 4/27/98 RU 3 IA P ocahontas 395 acres 2 oz/acre Broadcast , ground N/R Hornet

PLANTS I008079

- 005 C orn 5/5/98 RU 2 IA C alhoun 938 acres 2 oz/acre Broadcast , ground N/R Hornet

PLANTS I008079

- 006 Corn 4/27/98 RU 3 IA P ocahontas 837 acres 2.00 oz/acre Broadcast , ground N/R Hornet

PLANTS I008079

- 007 C orn 4/28/98 RU 2 IA P ocahontas 392 acres 2 oz/acre Broadcast , ground F Hornet

PLANTS I008079

- 008 C orn 5/12/98 RU 2 IA P ocahontas 90 acres 2 oz/acre Broadcast , ground F Hornet

PLANTS I008079

- 009 C orn 4/26/98 RU 2 IA P ocahontas 898 acres 2 oz/acre Broadcast , ground F Hornet

PLANTS I008079

- 010 C orn 5/12/98 RU 2 WI W alworth 90 acres 3.20 oz/acre Broadcast , ground N/R Hornet

PLANTS I008079

- 011 C orn 4/26/98 RU 2 IA P ocahontas 911 acres 2.00 oz/acre Broadcast , ground N/R Hornet

PLANTS I008187

- 001 C orn 12/7/98 RU 2 IA B remer 35 acres 2 oz/acre Broadcast , ground N/R Hornet

PLANTS I008187

- 002 C orn 12/6/98 RU 2 IL P eoria 69 acres 2 oz/acre Broadcast , ground N/R Hornet

PLANTS I008187

- 003 C orn 12/6/98 RU 2 IL M arshall All 100

acres 2.4 0 oz/acre Broadcast , ground N/R Hornet

### Page 38 of 47 Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total

Magnitude Appl. Rate Appl. Method Formul

ation 3 Product

PLANTS I008187

- 004 C orn 12/15/98 RU 2 NE B oone 61 of 75

acres 2.40 oz/acre Broadcast , ground N/R Hornet

PLANTS I008324

- 001 Agricultural

a rea 5/15/98 RU 3 OH H uron 33 acres 2.40 oz/acre Broadcast , ground N/R Hornet

PLANTS I008324

- 002 Agricultural

a rea 5/1/98 UN 1 MN Goodhue 90 acres 2.40 oz/acre Broadcast , ground N/R Hornet

PLANTS I008324

- 003 Agricultural

a rea 5/15/98 MA 3 MN Dakota 100 acres 3.58 oz/acre Broadcast , ground N/R Hornet

PLANTS I008324

- 004 Agricultural

a rea 5/6/98 RU 2 IA P ocahontas 259 acres 2.00 oz/acre Broadcast , ground N/R Hornet

PLANTS I008335

- 001 Agricultural

a rea 6/9/98 RU 2 WY Fremont 124 acres 2 oz/acre N/R N/R Stinger

PLANTS I008455

- 001 C orn 2/5/99 RU 2 IN Parke 144 acres 2.4 oz/acre N/R Hornet

PLANTS I008455

- 002 C orn 2/24/99 RU 2 IA Sioux All 2.4 oz/acre N/R Hornet

PLANTS I009507

- 001 Soybean 7/22/99 RU 3 SD Roberts 10 acres 2.0 pts/acre Broadcast , ground N/R Curtail

PLANTS I009509

- 001 A sparagus 9/2/99 RU 3 WA Franklin 250 acres N/R N/R N/R Stinger

PLANTS I009512

- 001 C orn 6/13/98 RU 3 ND Cass 50% of 53

acres 3.2 oz/acre Broadcast , ground G Hornet

PLANTS I009512

- 002 C orn 6/4/99 MA 3 IN Howard All 3.20 oz/acre Broadcast , ground G Hornet

PLANTS I009512

- 003 C orn 6/23/99 UN 3 WI Pepin All 2.40 oz/acre Broadcast , ground G Hornet

PLANTS I009512

- 004 Soybean 6/23/99 RU 2 MN Mower 50 plants 2.40 oz/acre Broadcast , ground G Hornet

PLANTS I009512

- 005 Alfalfa 6/23/99 RU 2 WI Pierce 20 acres 2.4 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 007 C orn 5/3/99 RU 1 WI P ierce 400 acres 2.4 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 008 C orn 5/1/99 RU 3 NE T hurston 30 of 60

acres 3.5 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 009 C orn 5/10/99 RU 2 MN R ice 80 acres 2.4 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 010 Agricultural

a rea 5/15/99 UN 1 MN G oodhue 200 acres 2.4 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 011 C orn 5/10/99 RU 2 SD G rant All 2.4 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 012 Agricultural

a rea 5/15/99 MA 2 MN Le S ueur All 4.0 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 013 C orn 5/20/99 RU 2 MN M orrison 60 acres 2.4 oz/acre Broadcast , ground N/R Hornet

### Page 39 of 47 Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total

Magnitude Appl. Rate Appl. Method Formul

ation 3 Product

PLANTS I009512

- 014 C orn 8/11/99 MA 2 MN Mower 214 acres 2.4 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 015 C orn 8/11/99 MA 2 MN Mower 216 acres 2.4 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 016 C orn 6/13/99 MA 2 MN Mower 600 acres 2.4 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 017 C orn 8/4/99 RU 2 MN Winona 75 of 126

acres 3.2 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 018 C orn 8/16/99 RU 2 IL C arroll All 3.2 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 019 C orn 9/8/99 RU 2 WI C rawford All 3.2 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 020 C orn 9/15/99 RU 2 IN PIKE All 2.6 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 021 C orn 9/22/99 RU 2 OH Hardin 45 of 73

acres 2.4 oz/acre Broadcast , ground Hornet

PLANTS I009512

- 022 C orn 9/25/99 RU 2 NE Red Willow All 1.2 oz/acre B and N/R Hornet

PLANTS I009512

- 023 C orn 9/23/99 MA 2 MN Dakota All 2.4 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 024 C orn 6/23/99 MA 2 MN Rock 37 of 76

acres 2.4 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 025 C orn 7/15/99 MA 2 MN L yon 40 acres 3.2 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 026 C orn 10/18/99 RU 3 IA D ubuque All 3.2 oz/acre Broadcast , ground N/R Hornet

PLANTS I009512

- 027 C orn 10/13/99 RU 3 MN F illmore All 2.9 oz/acre Broadcast , ground N/R Hornet

PLANTS I009669

- 004 C orn 7/5/99 RU 1 IA Jasper All 2.4 oz/acre Broadcast , air N/R Hornet

PLANTS I009969

- 003 C orn 9/13/99 RU 3 NE Furnas All 2.4 oz/acre Broadcast , ground N/R Hornet

PLANTS I009969

- 005 C orn 6/16/99 RU 2 WI Crawford All 3.2 oz/acre Broadcast , ground N/R Hornet

PLANTS I010414

- 001 Turf 4/1/00 MA 3 WA Spokane N/R N/R Confront

PLANTS I010743

- 001 T axus media 6/19/00 RU 3 MI Ottawa 18 acres 8 oz/ ? Spray , ground N/R Lontrel

PLANTS I010743

- 002 Y ews 6/19/00 RU 3 MI O ttawa 35 acres 8 oz/ ? SPRAY N/R Lontrel

PLANTS I010837

- 016 C orn 6/2/00 UN 2 IL Lee All N/R N/R N/R Hornet

PLANTS I010927

- 001 C orn 5/5/00 RU 2 IA D ubuque All 7 lbs/acre Soil incorporation N/R Accent Gold

PLANTS I010927

- 015 C orn 5/2/99 RU 3 IA F ranklin 132 acres 4 oz/acre Spray N/R Scorpion III

TERREST

RIAL I011897

- 002 Agricultural

a rea 7/1/00 MI 3 WA S pokane Unknown N/R C ompost C omp

ost N/R

PLANTS I012357

- 002 C orn 5/3/01 UN 2 MN All N/R Broadcast , ground N/R Hornet

### Page 40 of 47 Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total

Magnitude Appl. Rate Appl. Method Formul

ation 3 Product

PLANTS I012357

- 003 C orn 5/29/01 UN 2 MN All N/R Broadcast , ground N/R Hornet WDG

PLANTS I012363

- 002 Turf RU 4 PA 3 pint/acre Broadcast,

unincorporated Coftront/

Millennium

PLANTS I012366

- 008 Corn, field 4/27/01 RU 3 IA C arroll 30 acres 4 oz/acre Broadcast , ground Scorpion III

PLANTS I012366

- 009 Corn, field 4/25/01 RU 2 IA Hardin 105 acres 4 oz/acre Broadcast , ground Scorpion III

PLANTS I012366

- 010 Corn, field 4/26/01 RU 2 IA Hardin 134 acres 4 oz/acre Broadcast , ground Scorpion III

PLANTS I012366

- 029 Corn, field 5/1/01 RU 3 WI Grant 20 of 23

acres 3.60 oz/acre Broadcast , ground G Hornet

PLANTS I012366

- 030 Corn, field 5/1/01 RU 3 MN Steele 80 acres 3.00 oz/acre Broadcast , ground G Hornet

PLANTS I012366

- 031 Corn, field 5/6/01 RU 3 IN M ontgomery 203 acres 1.20 oz/acre Broadcast , ground G Hornet

PLANTS I012366

- 032 Corn, field 5/3/01 UN 3 MN 47.70 acres 4.00 oz/acre Broadcast , ground Hornet

PLANTS I012366

- 033 Corn, field 5/1/01 UN 3 MN 33.70 acres 4.00 oz/acre Broadcast , ground G Hornet WDG

PLANTS I012366

- 034 Corn, field 4/14/01 RU 2 IN C ass 65.0 acres 3.00 oz/acre Broadcast , ground G Hornet WDG

PLANTS I012366

- 035 Corn, field 5/9/01 RU 2 IA D ubuque 20 of 42

acres 3.00 oz/acre Broadcast , ground G Hornet WDG

PLANTS I012366

- 036 Corn, field 5/2/01 RU 3 WI D ane 40 acres 4.00 oz/acre Broadcast , ground G Hornet WDG

PLANTS I012366

- 037 Corn, field 5/10/01 RU 3 IA L inn 99 of 139

acres 4.00 oz/acre Broadcast , ground G Hornet WDG

PLANTS I012366

- 038 Corn, field 4/19/01 RU 3 IL S t Clair 90 acres 3.00 oz/acre G Hornet WDG

PLANTS I012366

- 039 Corn, field 4/24/01 RU 3 IN T ippecanoe 62 of 96

acres 3.00 oz/acre Broadcast , ground G Hornet WDG

PLANTS I012366

- 040 Corn, field 4/26/01 RU 3 MN Brown 21 acres 2.40 oz/acre Broadcast , ground G Hornet WDG

PLANTS I012366

- 041 Corn, field 4/28/01 RU 3 WI Richland 294 acres 4.00 oz/acre Broadcast , ground DF Hornet WDG

PLANTS I012366

- 042 Corn, field 6/14/01 RU 3 IL Whiteside 174 acres 3.00 oz/acre Broadcast , ground DF Hornet WDG

PLANTS I012366

- 043 Corn, field 4/29/01 RU 3 IA M uscatine 94 acres 3.00 oz/acre Broadcast , ground G Hornet WDG

PLANTS I012366

- 044 Corn, field 5/9/01 RU 3 WI D ane 31 acres 4.00 oz/acre Broadcast , ground G Hornet WDG

PLANTS I012366

- 055 Corn, field 5/9/01 RU 3 IA D ubuque 20 of 42

acres 3.0 oz/acre Broadcast , ground G Hornet

PLANTS I012366

- 061 Corn, field 5/15/01 RU 3 WI G rant 20 of 23

acres 3.60 oz/acre Broadcast , ground G Hornet

### Page 41 of 47 Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total

Magnitude Appl. Rate Appl. Method Formul

ation 3 Product

PLANTS I012366

- 062 Corn, field 5/9/01 UN 2 IA Hardin 105 acres 4.00 oz/acre Broadcast , ground G Scorpion III

PLANTS I012366

- 063 Corn, field 4/26/01 UN 2 IA Hardin 134 acres 4.00 oz/acre Broadcast , ground Scorpion III

PLANTS I012366

- 066 Corn, field 6/2/00 RU 3 IL B ureau 20 acres 4.00 oz/acre Broadcast , ground Hornet

PLANTS I012366

- 067 Corn, field 5/10/00 M 3 KS E dwards 126 acres 2.4 oz/acre Broadcast , ground Hornet

PLANTS I012366

- 068 Corn, field 3/30/01 RU 2 IL 160 acres 2.40 oz/acre Broadcast , ground Hornet

PLANTS I012366

- 069 Corn, field 4/30/01 RU 3 OH Wood 7 acres 4.12 oz/acre Broadcast , ground Hornet

PLANTS I012366

- 070 Corn, field 5/2/01 RU 3 IA D ubuque 30 acres 2.40 0z/acre Broadcast , ground Hornet

PLANTS I012366

- 071 Corn, field 5/24/01 RU 3 WI L afayette 60 acres 2.40 oz/acre Broadcast , ground Hornet

PLANTS I012366

- 072 Corn, field 5/2/00 RU 3 WI C olumbia 60 acres 3.20 oz/acre Broadcast , ground Hornet

PLANTS I012366

- 073 Corn, field 4/9/01 RU 3 IL P ike 20 acres 2.40 oz/acre Broadcast , ground Hornet

PLANTS I012367

- 001 Turf,

residential

area 12/29/01 RU 4 CA Unknown N/R Broadcast, soil

incorporated N/R

PLANTS I012556

- 001 Corn 4/26/01 RU 3 MN Brown 21 acres 2.40 oz/acre Broadcast , ground G Hornet

PLANTS I012627

- 002 Turf,

residential

area 1/22/02 RU 3 WA Spokane Unknown

PLANTS I012628

- 002 Turf,

residential

area 3/7/02 RU 3 CA Los Angeles

PLANTS I012628

- 003 Turf,

residential

area RU 3 CA Los Angeles

PLANTS I013550

- 003 Corn 5/22/02 RU 2 IL Morgan 862 plants

and trees 3.0 oz/acre Spray , air Hornet

PLANTS I013550

- 009 Corn, field 5/10/02 RU 1 MN L acqui Parle 50 acres Spray , ground Hornet

PLANTS I013554

- 046 N/R 7/1/02 M 2 SD Douglas 68 acres Accent

PLANTS I013554

- 048 N/R 7/22/02 M 2 WI Chippewa 65 acres Accent

PLANTS I013636

- 001 Corn, field 4/15/02 RU 2 MO P ettis 72 of 149

acres Broadcast Hornet

PLANTS I013636

- 004 Agricultural

Area 5/1/02 RU 2 WI P ierce 373 acres Broadcast , ground Hornet

### Page 42 of 47 Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total

Magnitude Appl. Rate Appl. Method Formul

ation 3 Product

PLANTS I013636

- 008 N/R RU 4 CANADA Curtail M

PLANTS I013636

- 025 Corn, field 4/23/01 RU 2 TN D yer 80 acres Broadcast , ground Accent

PLANTS I013636

- 032 Corn, field 4/28/01 RU 2 IN White 313 acres 2.40 oz/ acre Broadcast , ground Hornet

PLANTS I013883

- 028 Road 7/23/97 RU 2 WA Pierce N/R Spray , ground

PLANTS I013884

- 006 Pasture 6/11/98 RU 3 WA Chelan N/R Ground

PLANTS I014702

- 002 Potato 7/23/03 RU 2 ID Teton N/R N/R Ground N/R Curtail

PLANTS I014702

- 003 Wheat 5/15/03 RU 3 ND Stutsman 120 acres 1.75 pts/acre Broadcast , ground N/R Curtail M

PLANTS I014702

- 014 Corn, field 4/28/03 RU 2 IN Jasper 46 acres Broadcast , ground Hornet

PLANTS I014702

- 016 Corn, field 5/1/03 RU 3 NE Custer 1607.93

acres 3.0 gal /acre Broadcast , ground WP Hornet

PLANTS I014806

- 001 Agricultural

area 7/1/03 RU 2 ID Bannock 3020 acres N/R Ground N/R Curtail

PLANTS I015748

- 017 Wheat 6/6/04 RU 3 MT Richland 36 acres Spray EC WideMatch M

PLANTS I015748

- 019 Lettuce 6/25/04 M 2 AZ Yuma 15 acres N/R N/R EC Stinger

PLANTS I015748

- 022 Corn, field 5/20/03 RU 3 OH Seneca 36 acre s 0.7 lbs/ acre G Hornet

PLANTS I016962

- 030 Corn, field 4/15

-

7/21 /05 RU 2 KS Franklin 857 acres 3 oz/acre Broadcast DF Hornet WDG

PLANTS I016962

- 032 Flax 6/12/05 RU 2 ND 180 acres Curtail M

PLANTS I016962

- 039 Corn, field 6/16/05 RU 3 IA Winneshiek 286 a cres 3.5 oz /acre DF Hornet WDG

PLANTS I016962

- 040 Corn, field 6/15/05 RU 3 IA Shelby 265 a cres 3 oz/acre DF Hornet WDG

PLANTS I016962

- 041 Corn, field 6/1/05 UN 3 MN Wabasha 342 a cres 4 oz/acre Hornet

PLANTS I016962

- 045 Corn, field 4/29/05 RU 2 WI Lafayette 50 a cres 3 oz/acre DF Hornet WDG

PLANTS I016962

- 046 Alfalfa 6/7/05 RU 2 WI Ozaukee 30 a cres 3 oz/acre Hornet

PLANTS I016962

- 048 Corn, field 6/9/05 RU 2 NE Hall 22 a cres 1.33 pts/acre WideMatch

PLANTS I017837

- 017 Grape MA 3 CA San Luis

Obispo 90 oz/ac re Spray , ground N/R Transline

PLANTS I020627

- 031 Right

- of

way, road 7/10/01 MI 2 WA Benton Unknown Ground

PLANTS I020998

- 029 V ineyard UN 3 WA Walla Walla Ground

### Page 43 of 47 Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total

Magnitude Appl. Rate Appl. Method Formul

ation 3 Product

PLANTS I021276

- 010 N ursing

home UN 3 WA Spokane Ground

PLANTS I022082

- 033 Corn, field 6/8/10 UN 2 IA Chickasaw 100% of

138.2 acres

PLANTS I023302

- 021 Wheat,

spring 7/1/11 UN 3 ND Pembina 100 % of

423.2 acres 0.3 oz /acre Broadcast , ground N/R Accent/

Wide M atch

PLANTS I023302

- 025 Wheat,

spring 6/27/11 RU 2 MN Kittson 100 % of

560 acres Broadcast , ground N/R Wide M atch

PLANTS I023302

- 040 Wheat,

spring 7/13/11 RU 2 ND Pembina 100% of

38.7 acres 0.3 oz/acre Broadcast , ground Accent/

WideM atch

PLANTS I023574

- 002 Corn 4/21/11 UN 2 MN Lyon 2,1370

acres of

corn 1.78 pts/acre Pre

- emerge , ground Sure S tart

Herb GF2708

PLANTS I023574

- 006 Agricultural

area 6/9/11 UN 2 NE Greeley 70 acres 2 p ts/acre Broadcast , ground Sure S tart

Herb GF2708

PLANTS I023574

- 053 Agricultural

area 5/25/10 UN 2 KY Jefferson 100% of

349 acres 2 pt Broadcast , ground EC Sure Start

Herb

PLANTS I023574

- 054 Corn 4/30/10 UN 2 IA Clinton 100% of 71

acres Pre

- emerge , ground WP Hornet

PLANTS I023574

- 054 Corn 4/30/10 UN 2 IA Clinton 100% of 71

acres Pre

- emerge , ground EC Sure Start

Herb

PLANTS I023574

- 055 Corn, field 5/3/10 UN 2 IA Jackson 100% of

645 ac r e s 2 pt Pre

- emerge , ground WP Hornet

PLANTS I023574

- 055 Corn, field 5/3/10 UN 2 IA Jackson 100% of

645 acre s Pre

- emerge , ground EC Sure Start

Herb

TERREST

RIAL I023574

- 061 Corn UN 2 IN 1,200 acres Sure Start

Herb

TERREST

RIAL I023574

- 062 UN 2 IA Sure Start

Herb



### Abbreviations: Appl.=Application; N/R=Not Recorded

1 

### Legality Code: RU=Registered Use, M=Misuse, MA=Misuse (Accidental), MI=Misuse (Intentional), U N =Unknown

2 

### Certainty Code: 0=Unrelated, 1=Unlikely, 2=Possible, 3=Probable, 4=Highly Probable. N/ R=Not Reported

3 

### Formulation Code: DF=Dry Flowable; EC=Emulsifiable Concentrate; F= Flowable; G=Granular; WDG=Water Dispersable Granule; WP=Wettable Powder

### Page 44 of 47 

## Table B

- 3. Incidents in the EIIS for PC 117404: Clopyralid triethanolamine as of 10/31/13

Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total Magnitude Appl. Rate Appl. Method Formulation 3 Product

PLANTS I012701

- 001 Greenhouse 2/ 13 / 02 UN 3 OH < 100 Confront



### A bbreviations: Appl.=Application; N/R=Not Recorded

1 

### Legality Code: RU=Registered Use, M=Misuse, MA=Misuse (Accidental), MI=Misuse (Intentional), U N =Unknown

2 

### Certainty Code: 0=Unrelated, 1=Unlikely, 2=Possible, 3=Probable, 4=Highly Probable. N/R=Not Reported

3 

### Formulation Code: DF=Dry Flowable; EC=Emulsifiable Concentrate; F= Flowable; G=Granular; WDG=Water Dispersable Granule; WP=Wettable Powder



## Table B

- 4. Incidents in the EIIS for PC 117423: Clopyralid potassium as of 10/31/13

Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total

Magnitude Appl. Rate Appl. Method Formul

ation 3 Product

PLANTS I012525

- 004 Corn 5/5/01 RU 3 IN C ass All 4 oz/acre Broadcast , ground N/R Hornet WDG

P LANTS I012525

- 005 Corn 4/27/01 RU 3 IN Benton All 3.20 oz/acre Broadcast , ground N/R Hornet WDG

P LANTS I012525

- 006 Corn 5/10/01 RU 3 IA Linn All 4.00 oz/acre Broadcast , ground N/R Hornet WDG

P LANTS I012525

- 007 Corn 5/10/01 RU 3 IA Linn 99 ACRES 4.00 oz/acre Broadcast , ground N/R Hornet WDG

P LANTS I013636

- 003 Agricultural

Area 4/15/01 RU 2 IL Mason all 589.8

acres Broadcast , ground Hornet WDG

P LANTS I013636

- 024 Corn, field 5/20/02 RU 2 NE Custer 155 acres Broadcast , ground Hornet WDG

P LANTS I013636

- 051 Corn, field 4/29/01 RU 3 WI Grant 99.10 acres 4 oz/acre Broadcast , ground Hornet

P LANTS I013636

- 052 Corn, field 5/1/02 RU 2 IL Montgomery 93 acres 3.0 oz/acre Broadcast , ground Hornet WDG

P LANTS I013636

- 053 Corn, field 4/29/02 RU 2 WI W aukesha 38 acres 3.0 oz/acre Broadcast , ground Hornet WDG

PLANTS I013636

- 054 Agricultural

area 5/20/02 RU 2 IA Poweshiek 15 acres 3.0 oz/acre Hornet WDG

PLANTS I013636

- 055 Corn, field 4/20/02 RU 2 IN Marshall 500 out of

950 acres 4.0 oz/acre Broadcast , ground Hornet WDG

P LANTS I013636

- 056 Corn, field 5/1/02 RU 2 WI 24 acres 3.0 oz/acre Broadcast , ground Hornet WDG

P LANTS I013636

- 057 Corn, field 5/10/02 RU 3 WI Sauk 99 acres 4.0 oz/acre Broadcast , ground Hornet WDG

P LANTS I013636

- 058 Corn, field 5/15/02 RU 2 MN L e Sueur 260 out of

302 acres 2.5 oz/acre Broadcast , ground Hornet WDG

P LANTS I013636

- 059 Corn, field 5/14/02 RU 2 NE Phelps 120 acres 4.0 oz/ acre Broadcast , ground Hornet WDG

P LANTS I013636

- 060 Corn, field 5/1/02 RU 2 NE Hall 802 out of

896 acres 1.5 oz/acre Band Hornet WDG

### Page 45 of 47 Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total

Magnitude Appl. Rate Appl. Method Formul

ation 3 Product

P LANTS I013636

- 061 Corn, field 4/28/02 RU 4 NE C uster 132 acres 2.40 oz/acre Broadcast , ground Hornet WDG

P LANTS I013636

- 062 Corn, field 5/2/02 RU 4 NE Buffalo 39 acres 3.0 oz/acre Broadcast , ground Hornet WDG

P LANTS I013636

- 063 Corn, field 5/8/02 RU 4 NE Knox 110 out of

190 acres 3.0 oz/acre Broadcast , ground Hornet WDG

P LANTS I013636

- 064 Corn, field 4/28/02 RU 4 IA Lee 132 acres 2.40 oz/acre Broadcast , ground Hornet WDG

P LANTS I013636

- 065 Corn, field 5/2/02 RU 3 IA B uchanan 147 acres 4.0 oz/acre Broadcast , ground Hornet WDG

P LANTS I013636

- 066 Corn, field 6/1/02 RU 2 MN Rice 26 acres 3.0 oz/acre Broadcast , ground Hornet WDG

PLANTS I013636

- 067 Corn, field 4/20/02 RU 2 NE D awson 390 out of

425 acres 3.0 oz/acre Broadcast , ground Hornet WDG

PLANTS I013636

- 068 Corn, field 5/15/02 RU 2 MN C arver 3/0 oz/acre Broadcast , ground Hornet WDG

P LANTS I013636

- 069 Corn, field 5/3/02 RU 3 NE Knox 170 acres 4.0 oz/acre Broadcast , ground Hornet WDG

P LANTS I014702

- 021 Corn, field 6/27/03 RU 3 NE Hall 899 acres 3 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 022 Corn, field 6/16/03 RU 2 WI Rock 6.5 acres 0.75 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 023 Corn, field 6/20/02 RU 2 IL Fulton 30 out of 36

acres 3 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 024 Corn 5/13/03 RU 3 NE Franklin 35.85 acres 4 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 025 Corn 5/13/03 RU 3 NE Franklin 35.35 acres 4 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 026 Corn 5/10/03 RU 3 NE Franklin 39 acres 4 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 027 Corn 5/10/03 RU 3 NE Franklin 39 acres 4 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 028 Corn, field 6/23/03 RU 2 NE Hall 63 acres 3 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 029 Corn, field 6/23/03 RU 2 NE Hall 185 acres 3 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 030 Corn, field 5/14/03 RU 2 IA Cedar 385 acres 4 oz/acre Broadcast , ground G Hornet

PLANTS I014702

- 031 Corn, field 6/23/03 RU 2 NE Hall 185 acres 3 oz/acre Broadcast , ground G Hornet

PLANTS I014702

- 032 Corn, field 7/5/03 RU 2 ND Dickey 55 acres 3 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 033 Corn, field 7/5/03 RU 2 ND Dickey 68 acres 3 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 034 Corn, field 6/30/02 RU 3 IL Kankakee 12 acres 2.5 pts/acre Broadcast , ground G Hornet

P LANTS I014702

- 035 Corn, field 5/5/01 RU 2 IL Jasper 800 acres 3 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 036 Corn, field 5/1/02 RU 2 NE Dixon 257 of 277

acres 4 oz/acre Broadcast , ground G Hornet

### Page 46 of 47 Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total

Magnitude Appl. Rate Appl. Method Formul

ation 3 Product

P LANTS I014702

- 037 Corn, field 4/19/02 RU 2 IA Washington 16.5 of 36

acres 3 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 038 Clover 4/11/03 RU 3 MN Olmsted 18 acres 4 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 039 Corn, field 4/29/03 RU 3 WI Dodge 250 acres 4 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 040 Corn, field 4/27/03 RU 2 WI Walworth 300 acres 4 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 041 Corn, field 4/29/03 RU 2 WI Waukesha 110 acres 4 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 042 Corn, field 5/27/03 RU 2 WI Brown 15 of 30

acres 3 oz/acre Broadcast , ground G Hornet

P LANTS I014702

- 043 Corn, field 4/29/03 RU 2 WI Columbia 200 acres 4 oz/acre Broadcast , ground G Hornet

PLANTS I014702

- 044 Soybean 5/9/03 M 3 WI Dane 14.5 of 29

acres 4 oz/acre Broadcast , ground G Hornet

PLANTS I014702

- 045 Agricultural

area 5/2/03 UN 3 WI Rock 76 acres G Hornet

P LANTS I015748

- 015 Corn, field 5/22/03 RU 3 MI 100 acres 3 oz/acre N/R G Hornet

P LANTS I015748

- 024 Corn, field 4/15/04 RU 2 IL Lawrence 80 acres 3 oz/acre d ry N/R G Hornet

P LANTS I015748

- 026 Corn, field 5/27/04 M 3 IN Marshall 500 acres 4 oz/acre Broadcast , ground G Hornet

P LANTS I015748

- 027 Corn 5/24/04 M 3 IN Pulaski 500 acres 2.8 oz/acre G Hornet

P LANTS I015748

- 034 Corn, field 6/11/04 RU 3 MO Nodaway 155 acres 3 oz/acre Spray , ground G Hornet

P LANTS I015748

- 036 Corn, field 6/2/04 RU 3 MO Linn 287 acres 3 oz/acre N/R G Hornet

P LANTS I015748

- 037 Corn, field 6/20/04 RU 3 MO Chariton 128 acres 3 oz/acre N/R G Hornet

P LANTS I015748

- 038 Corn, field 6/2/04 RU 3 MO Carroll 64 acres 3 oz/acre dry N/R G Hornet

P LANTS I015748

- 039 Corn, field 6/2/04 RU 3 MO Carroll 57 acres 3 oz/ acre d ry N/R G Hornet

P LANTS I015748

- 042 Soybean 5/10/03 UN 3 WI Pepin 607 acres 3.2 oz/acre Spray G Hornet

P LANTS I016962

- 002 Corn 5/22/04 RU 2 MI Jackson 140 acres Broadcast DF Hornet WDG

PLANTS I016962

- 033 Corn, field 5/3/05 RU 3 WI Pierce 260 acres 4 oz/acre DF Hornet

PLANTS I016962

- 035 Corn, field 5/5/05 RU 2 IA Ringgold 100 acres 2.7 qts/acre DF Hornet WDG

P LANTS I016962

- 036 Corn, field 4/24/05 RU 2 WI Columbia 411 acres 4 oz/acre DF Hornet WDG

P LANTS I016962

- 047 Corn, field 5/16/05 RU 3 WI Fond Du Lac 40 a cres 4 oz/acre DF Hornet WDG

PLANTS I023574

- 051 Agricultural 5/28/10 UN 2 WI Juneau 100% corn 2 qt. Pre

- emerge , ground WDG Hornet

### Page 47 of 47 Type Incident ID Use Site Date Legality 1 Certainty 2 State County Total

Magnitude Appl. Rate Appl. Method Formul

ation 3 Product

area



### A bbreviations: Appl.=Application; N/R=Not Recorded

1 

### Legality Code: RU=Registered Use, M=Misuse, MA=Misuse (Accidental), MI=Misuse (Intentional), U N =Unknown

2 

### Certainty Code: 0=Unrelated, 1=Unlikely, 2=Possible, 3=Probable, 4=Highly Probable. N/R=Not Repo rted

3 

### Formulation Code: DF=Dry Flowable; EC=Emulsifiable Concentrate; F= Flowable; G=Granular; WDG=Water Dispersable Granule; WP=Wettable Powder