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Environmental Assessment Rangeland Grasshopper and 

Mormon Cricket Suppression Program

New Mexico

EA Number: NM-20-01

Prepared by:

Animal and Plant Health Inspection Service

270 South 17th Street 

Las Cruces, NM 88005

May 21, 2020
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containers
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Table of Contents

I. Need for Proposed Action...................................................................................................... 5

A. Purpose and Need Statement .............................................................................................. 5

B. Background Discussion ...................................................................................................... 5

C. About This Process............................................................................................................. 6

II. Alternatives............................................................................................................................ 7

A. No Suppression Program Alternative ................................................................................. 8

B. Insecticide Applications at Conventional Rates or Reduced Agent Area Treatments with 

Adaptive Management Strategy (Preferred Alternative).................................................... 8

C. Experimental Treatment............................................................................. 9

III. Affected Environment............................................................................................................ 9

A. Description of Affected Environment............................................................................... 10

B. Site-Specific Considerations............................................................................................. 11

1. Human Health ................................................................................................................ 11

2. Nontarget Species .......................................................................................................... 11

3. Socioeconomic and Cultural Resource Issues ............................................................... 12

4. Special Considerations for Certain Populations ............................................................ 13

IV. Environmental Consequences.............................................................................................. 13

A. Environmental Consequences of the Alternatives............................................................ 14

1. No Suppression Program Alternative ............................................................................ 14

2 Insecticide Applications at Conventional Rates or Reduced Agent Area Treatments 

with Adaptive Management Strategy............................................................................. 15

B. Other Environmental Considerations................................................................................ 24

1. Cumulative Impacts....................................................................................................... 24

2. Executive Order No. 12898, Federal Actions to Address Environmental Justice in 

Minority Populations and Low-Income Populations..................................................... 25

3. Executive Order No. 13045, Protection of Children from Environmental Health Risks 

and Safety Risks............................................................................................................. 25

4. Tribal Consultation ........................................................................................................ 26

5. Executive Order 13186, Responsibilities of Federal Agencies to Protect Migratory 

Birds................................................................................................26

6. Endangered Species Act ................................................................................................ 27

7. Bald and Golden Eagle Protection Act .......................................................................... 27

8. Additional Species of Concern ...................................................................................... 28

9. Fires and Human Health Hazards.................................................................................. 28

10. Cultural and Historical Resources ................................................................................. 29

V. Literature Cited .................................................................................................................... 29

VI. Listing of Agencies and Persons Consulted......................................................................... 35

Appendix A: APHIS Rangeland Grasshopper and Mormon Cricket Suppression Program. 36

Appendix B: Chemical Safety & Emergency Spill Plan Information & Equipment...........39

Appendix C: Map of the Affected Environment.................................................................... 41

Appendix D: FWS/NMFS Correspondence........................................................................... 45

Appendix E: State and Tribal Species of Concern Review........................................48

Appendix F: Potential Experimental Treatments...................................................48

Appendix G: APHIS Response to Public Comments on the New Mexico Draft EA..........54
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Acronyms and Abbreviations

ac acre

a.i. active ingredient

AChE acetylcholinesterase

APHIS Animal and Plant Health Inspection Service 

BCF bioconcentration factor 

BLM Bureau of Land Management

CEQ Council of Environmental Quality

CFR Code of Federal Regulations

EA environmental assessment

e.g. example given (Latin, exempli gratia, “for the sake of example”)

EIS environmental impact statement

E.O. Executive Order

FONSI finding of no significant impact

FR Federal Register

FS Forest Service

g gram

ha hectare 

HHERA human health and ecological risk assessments

i.e. in explanation (Latin, id est “in other words.”)

IPM integrated pest management

lb pound

MBTA Migratory Bird Treaty Act 

MOU memorandum of understanding 

NEPA National Environmental Policy Act 

NHPA National Historic Preservation Act 

NIH National Institute of Health

ppm parts per million

PPE personal protective equipment 

PPQ Plant Protection and Quarantine 

RAATs reduced agent area treatments 

S&T Science and Technology

ULV ultra-low volume

U.S.C. United States Code

USDA United States Department of Agriculture 

USEPA United States Environmental Protection Agency

USFWS United States Fish and Wildlife Services
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Final Site-Specific Environmental Assessment 

Rangeland Grasshopper and Mormon Cricket Suppression Program

New Mexico

I. Need for Proposed Action

A. Purpose and Need Statement

An infestation of grasshoppers or Mormon crickets may occur in New Mexico. The Animal and 

Plant Health Inspection Service (APHIS) may, upon request by land managers or State 

departments of agriculture, conduct treatments to suppress grasshopper infestations as part of the 

Rangeland Grasshopper and Mormon Cricket Suppression Program (program). The term 

“grasshopper” used in this environmental assessment (EA) refers to both grasshoppers and 

Mormon crickets, unless differentiation is necessary.

Populations of grasshoppers that trigger the need for a suppression program are normally 

considered on a case-by-case basis. Participation is based on potential damage such as damage

to grassland areas and benefits of treatments including the protection of rangeland resources. The 

goal of the proposed suppression program analyzed in this EA is to reduce grasshopper 

populations to economically acceptable levels in order to protect rangeland ecosystems or 

cropland adjacent to rangeland.

This EA analyzes potential effects of the proposed action and its alternatives. This EA applies to 

a proposed suppression program that would take place from May 1, 2020 to October 31, 2020 in

New Mexico.

This EA is prepared in accordance with the requirements under the National Environmental 

Policy Act of 1969 (NEPA) (42 United States Code § 4321 et. seq.) and the NEPA procedural 

requirements promulgated by the Council on Environmental Quality, United States Department 

of Agriculture (USDA), and APHIS. A decision will be made by APHIS based on the analysis 

presented in this EA, the results of public involvement, and consultation with other agencies and 

individuals. A selection of one of the program alternatives will be made by APHIS for the 2020

Control Program for New Mexico.

B. Background Discussion

Rangelands provide many goods and services, including food, fiber, recreational opportunities, 

and grazing land for cattle (Havstad et al., 2007; Follett and Reed, 2010). Grasshoppers and 

Mormon crickets are part of rangeland ecosystems, serving as food for wildlife and playing an 

important role in nutrient cycling. However, grasshoppers and Mormon crickets have the 

potential to occur at high population levels (Belovsky et al., 1996) that result in competition with 

livestock and other herbivores for rangeland forage and can result in damage to rangeland plant 

species.
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In rangeland ecosystem areas of the United States, grasshopper populations can build up to 

economic infestation levels1 despite even the best land management and other efforts to prevent 

outbreaks. At such a time, a rapid and effective response may be requested and needed to reduce 

the destruction of rangeland vegetation. In some cases, a response is needed to prevent 

grasshopper migration to cropland adjacent to rangeland. 

APHIS surveys grasshopper populations on rangeland in the Western United States, provides 

technical assistance on grasshopper management to land owners and managers, and may 

cooperatively suppress grasshoppers when direct intervention is requested by a Federal land 

management agency or a State agriculture department (on behalf of a State or local government, 

or a private group or individual). APHIS’ enabling legislation provides, in relevant part, that ‘on 

request of the administering agency or the agriculture department of an affected State, the 

Secretary, to protect rangeland, shall immediately treat Federal, State, or private lands that are 

infested with grasshoppers or Mormon crickets’... (7 U.S.C. § 7717(c)(1)). The need for rapid 

and effective response when an outbreak occurs limits the options available to APHIS. The 

application of an insecticide within all or part of the outbreak area is the response available to 

APHIS to rapidly suppress or reduce grasshopper populations and effectively protect rangeland. 

In June 2002, APHIS completed an environmental impact statement (EIS) document concerning 

suppression of grasshopper populations in 17 Western States (Rangeland Grasshopper and 

Mormon Cricket Suppression Program, Environmental Impact Statement, June 21, 2002). The 

EIS described the actions available to APHIS to reduce the damage caused by grasshopper 

populations in Arizona, California, Colorado, Idaho, Kansas, Montana, Nebraska, Nevada, New 

Mexico, North Dakota, Oklahoma, Oregon, South Dakota, Texas, Utah, Washington, and 

Wyoming. In November 2019, APHIS published an updated EIS to incorporate the available 

data and analyze the environmental risk of new program tools. The risk analysis in the 2019 EIS 

is incorporated by reference. 

C. About This Process

The EA process for grasshopper management is complicated by the fact that there is very little 

time between requests for treatment and the need for APHIS to take action with respect to those 

requests. Surveys help to determine general areas, among the scores of millions of acres that 

potentially could be affected, where grasshopper infestations may occur in the spring of the 

following year. Survey data provides the best estimate of future grasshopper populations, yet 

environmental factors lead to certain forecasts where the specific treatment areas will be. 

Therefore examining specific treatment areas for environmental risk analysis under NEPA is 

typically not possible. At the same time, the program strives to alert the public in a timely 

 1 The “economic infestation level” is a measurement of the economic losses caused by a particular population level of 

grasshoppers to the infested rangeland. This value is determined on a case-by-case basis with knowledge of many factors 

including, but not limited to, the following: economic use of available forage or crops; grasshopper species, age, and density 

present; rangeland productivity and composition; accessibility and cost of alternative forage; and weather patterns. In 

decision making, the level of economic infestation is balanced against the cost of treating to determine an “economic 

threshold” below which there would not be an overall benefit for the treatment. Short-term economic benefits accrue during 

the years of treatments, but additional long-term benefit may accrue and be considered in deciding the total value gained by 

treatment. Additional losses to rangeland habitat and cultural and personal values (e.g., aesthetics and cultural resources), 

although a part of decision making, are not part of the economic values in determining the necessity of treatment.
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manner to its more concrete treatment plans and avoid or minimize harm to the environment in 

implementing those plans.

The current EIS provides a solid analytical foundation; however, it may not be enough to satisfy 

NEPA completely for actual treatment proposals. The program typically prepares a Draft EA 

tiered to the current EIS for each of the 17 Western States, or portion of a state, that may receive 

a request for treatment. The Draft EA analyzes aspects of environmental quality that could be 

affected by treatments in the area where grasshopper outbreaks are anticipated. The Draft EA 

will be made available to the public for a 30-day comment period. When the program receives a 

treatment request and determines that treatment is necessary, the specific site within the state will 

be evaluated to determine if environmental factors were thoroughly evaluated in the Draft EA. If 

all environmental issues were accounted for in the Draft EA, the program will prepare a Final 

EA and finding of no significant impact (FONSI). Once the FONSI has been finalized copies of 

those documents will be sent to any parties that submitted comments on the Draft EA, and to 

other appropriate stakeholders. To allow the program to respond to comments in a timely 

manner, the Final EA and FONSI will be posted to the APHIS website. The program will also 

publish a notice of availability in the same manner used to advertise the availability of the Draft 

EA.

II. Alternatives

To engage in comprehensive NEPA risk analysis APHIS must frame potential agency decisions

into distinct alternative actions. These program alternatives are then evaluated to determine the 

significance of environmental effects. The 2002 EIS presented three alternatives: (A) No Action; 

(B) Insecticide Applications at Conventional Rates and Complete Area Coverage; and (C) 

Reduced Agent Area Treatments (RAATs), and their potential impacts were described and 

analyzed in detail. The 2019 EIS was tiered to, and updated the 2002 EIS. Therefore the 2019 

EIS considered the environmental background or ‘No Action’ alternative of maintaining the 

program that was described in the 2002 EIS and Record of Decision. The 2019 EIS also 

considered an alternative where APHIS would not fund or participate in grasshopper suppression 

programs. The preferred alternative of the 2019 EIS allowed APHIS to update the program with 

new information and technologies that not were analyzed in the 2002 EIS. Copies of the 

complete 2002 and 2019 EIS documents are available for review at USDA-APHIS-PPQ, 270 

South 17th Street, Las Cruces, NM 88005 address. These documents are also available at the 

Rangeland Grasshopper and Mormon Cricket Program web site, 

http://www.aphis.usda.gov/plant-health/grasshopper. 

All insecticides used by APHIS for grasshopper suppression are used in accordance with 

applicable product label instructions and restrictions. Representative product specimen labels can 

be accessed at the Crop Data Management Systems, Incorporated web site at 

www.cdms.net/manuf/manuf.asp. Labels for actual products used in suppression programs will 

vary, depending on supply issues. All insecticide treatments conducted by APHIS will be 

implemented in accordance with APHIS’ treatment guidelines and operational procedures, 

included as Appendix 1 to this Final EA. 

This Final EA analyzes the significance of environmental effects that could result from the 

alternatives described below. These alternatives differ from those described in the 2019 EIS 
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because grasshopper treatments are not likely to occur in most of New Mexico and therefore the 

environmental baseline should describe a no treatment scenario. 

A. No Suppression Program Alternative

Under Alternative A, the No Action alternative, APHIS would not conduct a program to suppress 

grasshopper infestations within New Mexico. Under this alternative, APHIS may opt to provide 

limited technical assistance, but any suppression program would be implemented by a Federal 

land management agency, a State agriculture department, a local government, or a private group 

or individual.

B. Insecticide Applications at Conventional Rates or Reduced Agent Area 

Treatments with Adaptive Management Strategy (Preferred Alternative)

Under Alternative B, the Preferred Alternative, APHIS would manage a grasshopper treatment 

program using techniques and tools discussed hereafter to suppress outbreaks. The insecticides 

available for use by APHIS include the U.S. Environmental Protection Agency (USEPA) 

registered chemicals carbaryl, diflubenzuron, and malathion. These chemicals have varied modes 

of action: carbaryl and malathion work by inhibiting acetylcholinesterase (enzymes involved in 

nerve impulses); diflubenzuron is a chitin inhibitor. APHIS would make a single application per 

year to a treatment area, and could apply insecticide at an APHIS rate conventionally used for 

grasshopper suppression treatments, or more typically as reduced agent area treatments

(RAATs). APHIS selects which insecticides and rates are appropriate for suppression of a 

grasshopper outbreak based on several biological, logistical, environmental, and economical 

criteria. The identification of grasshopper species and their life stage largely determines the 

choice of insecticides used among those available to the program. RAATs are the most common 

application method for all program insecticides, and only rarely do rangeland pest conditions 

warrant full coverage and higher rates.

The RAATs strategy is effective for grasshopper suppression because the insecticide controls 

grasshoppers within treated swaths while conserving grasshopper predators and parasites in 

swaths not directly treated. RAATs can decrease the rate of insecticide applied by either using 

lower insecticide concentrations or decreasing the deposition of insecticide applied by alternating 

one or more treatment swaths. Both options are most often incorporated simultaneously into 

RAATs. Either carbaryl, diflubenzuron, or malathion would be considered under this alternative, 

typically at the following application rates:

• 8.0 fluid ounces (0.25 lb a.i.) of carbaryl ULV spray per acre;

• 0.75 or 1.0 fluid ounce (0.012 lb a.i.) of diflubenzuron per acre; or

• 4.0 fluid ounces (0.31 lb a.i.) of malathion per acre.

The width of the area not directly treated (the untreated swath) under the RAATs approach is not 

standardized. The proportion of land treated in a RAATs approach is a complex function of the 

rate of grasshopper movement, which is a function of developmental stage, population density, 

and weather (Narisu et al., 1999, 2000), as well as the properties of the insecticide (insecticides 

with longer residuals allow wider spacing between treated swaths). Foster et al. (2000) left 20 to 

50% of their study plots untreated, while Lockwood et al. (2000) left 20 to 67% of their 

treatment areas untreated. Currently the grasshopper program typically leaves 50% of a spray 
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block untreated for ground applications where the swath width is between 20 and 45 feet. For 

aerial applications, the skipped swath width is typically no more than 20 feet for malathion, 100 

feet for carbaryl and 200 feet for diflubenzuron. The selection of insecticide and the use of an 

associated swath widths is site dependent. Rather than suppress grasshopper populations to the 

greatest extent possible, the goal of this alternative is to suppress grasshopper populations to a 

desired level.

Insecticide applications at conventional rates and complete area coverage, is an approach that 

APHIS has used in the past but is currently uncommon. Under this alternative, carbaryl, 

diflubenzuron, or malathion would cover all treatable sites within the designated treatment block 

per label directions. The application rates under this alternative are typically at the following 

application rates:

• 16.0 fluid ounces (0.50 lb a.i.) of carbaryl spray per acre;

• 1.0 fluid ounce (0.016 lb a.i.) of diflubenzuron per acre; or

• 8.0 fluid ounces (0.62 lb a.i.) of malathion per acre.

The potential generalized environmental effects of the application of carbaryl, diflubenzuron, 

and malathion, under this alternative are discussed in detail in the 2019 EIS. A description of 

anticipated site-specific impacts from this alternative may be found in Part IV of this document.

C. Experimental Treatments 

APHIS-PPQ continues to refine its methods of grasshopper and Mormon cricket management in 

order to improve the abilities of the Rangeland Grasshopper and Mormon Cricket Suppression 

Program (herein referred to as the Program) to make it more economically feasible, and 

environmentally acceptable. These refinements can include reduced rates of currently used 

pesticides, improved formulations, development of more target-specific baits, development of 

biological pesticide suppression alternatives, and improvements to aerial (e.g., incorporating the 

use of Unmanned Aircraft Systems (UAS)) and ground application equipment. A division of 

APHIS-PPQ, Science and Technology’s (S&T) Phoenix Lab is located in Arizona and its 

Rangeland Grasshopper and Mormon Cricket Management Team (Rangeland Unit) conducts 

methods development and evaluations on behalf of the Program. The Rangeland Unit’s primary 

mission is to comply with Section 7717 of the Plant Protection Act and protect the health of 

rangelands (wildlife habitats and where domestic livestock graze) against economically 

damaging cyclical outbreaks of grasshoppers and Mormon crickets. The Rangeland Unit tests 

and develops more effective, economical, and less environmentally harmful management 

methods for the Program and its federal, state, tribal, and private stakeholders.

To achieve this mission, experimental plots ranging in area from less than one foot to 640 acres 

are used and often replicated. The primary purpose of these experiments is to test and develop 

improved methods of management for grasshoppers and Mormon crickets. This often includes 

testing and refining pesticide and biopesticide formulations that may be incorporated into the 

Program. These investigations often occur in the summer (May-August) and the locations 

typically vary annually. The plots often include “no treatment” (or control) areas that are 

monitored to compare with treated areas. Some of these plots may be monitored for additional 

years to gather information on the effects of utilized pesticides on non-target arthropods. Note 

that an Experimental Use Permit is not needed when testing non-labeled experimental pesticides 
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if the use is limited to laboratory or greenhouse tests, or limited replicated field trials involving 

10 acres or less per pest for terrestrial tests. Studies and experimental plots are typically located 

on large acreages of rangelands and the Rangeland Unit often works on private land with the 

permission of landowners. Locations of experimental trials will be made available to the 

appropriate agencies in order to ensure these activities are not conducted near sensitive species or 

habitats. Due to the small size of the experimental plots, no adverse effects to the environment, 

including protected species and their critical habitats, are expected, and great care is taken to 

avoid sensitive areas of concern prior to initiating studies.

Please see Appendix F for further information.

III. Affected Environment

A. Description of Affected Environment

The proposed suppression program included in this 2020 EA encompasses the entire state as we 

won’t know what areas are affected until our survey commences. For New Mexico, APHIS in 

this document considers mainly four ecologic regions to exist; these are: the short-grass prairie 

of the southern extent of Great Plains (Southern High Plains and the Southwestern Tablelands 

in the eastern counties), the Arizona/New Mexico Plateaus and Mesas (in the northwestern 

counties), the southern Rocky Mountains with the Arizona and New Mexico Mountains (northcentral and west central counties), the Chihuahuan Desert (in the southern counties). These 

four basic designated eco-regions are at the northeastern reach of the greater southwest desert 

area that extends from western Texas to south-central California.

The main watershed basins that dissect New Mexico are Upper Rio Grande and Upper

Colorado (San Juan) being fed from the state of Colorado, the Arkansas- White-Red

(Southern Canadian), Pecos, Lower Colorado (Zuni and Gila), Lower Rio Grande, Central

Closed (Estancia and Tularosa and Salt Basins), Southwest Closed (Mimbres), and TexasGulf (Southern High Plains).

New Mexico soils are of three basic soil orders: Aridisoils (being most common in arid zones),

Entisoils (incipient soil process), and Mollisoils (usually associated with the mountains).

Basically there are four weather zones found in New Mexico; Northern Chihuahuan Desert,

Southern High Plains, Southern Rockies and Arizona-New Mexico Plateau. These zones are

affected by colder temperatures increasing with elevation year round. Higher elevations of the 

upper mountain zones are associated with coniferous and alpine plants; receive more rain, 

snow and ice than lower mountain elevations. Average annual minimum temperature may

reach -25 to -20 degree Fahrenheit (°F). The intermediate elevations and mountain transition 

zone below 9,600 feet as l to 7,000 feet above sea level is dominated by mixed coniferous; fir 

and spruce and deciduous trees such as aspen, and some shrubs, such as bearberry, mountain 
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mahogany, and barberry, which receive slightly less moisture during the year with average 

minimum temperature lows of -15 to -10 °F.

Elevation below 7,000 to 4,500 feet are general considered the marginal limit of the Upper 

Sonoran Zone with most vegetation consisting of pine, juniper, oak, buckbrush, sagebrush and 

sagewort, rabbitbrush, wolfberry, hackberry, Apache plume and winterfat.

Elevation below 4,500 to 2,500 or the Lower Sonoran Zone has predominant vegetation 

consisting of mesquite, cottonwood, Jerusalem thorn, acacia, creosote bush, tarbush, 

greasewood, turpentine bush, sand shinnery, whitebrush, yucca, agave, desert willow, 

beargrass, desert candle, and various cacti, and along riparian zones willows, Russian olive, 

seep willow and salt.

The elevations below 5,400 feet are mostly open rangeland areas with the milder southwest 

part of the state having winter temperature lows between 15° F and 10° F, and rainfall averages 

of 12 inches annually. As one goes to eastward, rainfall averages increases to 16 inches or 

more, and winter temperatures fall to 5° F to 0° F lows. Further decreasing average lows 

naturally occur as one moves northward in the state.

Public land management covers about 50% of the New Mexico’s 33 counties that contain the 

state’s 77.67 million acres (121,356 mi2

). Of this 38.83 million acres of public land, the land 

surface management responsibility is mainly divided between the Bureau of Land Management

(16.5%) and the U.S Forest Service (12.0%), the State Land Office (11.9%) and Indian Trust

Lands (9.6%).

APHIS mainly does grasshopper suppression programs on level to rolling hill topography,

avoiding water resources, over grassland vegetation during daytime in warm weather with 

wind speeds less than 10 mph. Treatment activities are monitored by direct APHIS-Plant 

Protection and Quarantine (PPQ) supervision, and are found in Appendix 1.

For site specific information, maps or other visual representations of the suppression program

area will be included in Appendix A thru Appendix G.

B. Site-Specific Considerations

1. Human Health

The rangeland areas where treatments may occur are sparsely populated by isolated ranch 

units having mainly cattle operations and “ranchettes” (homesteads generally five acres or 

less). Rangeland grazing is the predominant livestock feeding method. A buffer of 1.25 miles 

from the treatment area to the perimeter of any town and other communities will be used. 
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Ranch buildings and structures (such as stock tanks) will have a buffer of 200 feet. Federal 

highways and State roads will have a buffer of 25 feet. Potential exposures to the general 

public from conventional application rates are infrequent and of low magnitude. The RAATs 

approach reduces this potential even further by using reduced rates and less actual directly 

treated area. The proposed program should benefit human and environmental health by 

reducing the risk of insect annoyance, blowing dust, higher light reflection and higher 

temperature on the semi-arid land surface. Sensitive areas to the general public will have 

designated buffers. Local law enforcement, fire departments EMS, hospitals and tribal 

agencies will be notified prior to any treatment as an advisory to access any safety risk, the 

treatment date and location and contact personnel.

2. Nontarget Species

Non-target species such as pollinators and other beneficial insects, which may be impacted, 

by the suppression program are those present during application in the sprayed swathes by

direct chemical contact, or by feeding upon the contacted surface of vegetation, litter or on 

affected grasshoppers. Some migratory and nesting birds in contact with the application may

temporarily be affected, mainly by feeding on treated grasshoppers or other insects, but not 

adversely. These suppression applications avoid water bodies and aquatic life, and due to the 

timing of these applications and their short residual life, the risk of their movement into

seasonal or permanent water is minimal. Pre-treatment monitoring will identify any potential 

nearby water source to insure that adequate buffers are used to protect these areas. 

Phytotoxicity has not been found to be a concern to rangeland plants when these chemicals 

are applied at the recommended rates.

Currently the F&WS has 52 Endangered and Threatened Species and 2 Candidate Species 

listed for New Mexico. The list of these species is found for individual species details at these

three following links: http://www.fws.gov/southwest/es/ES_Lists_Main.cfm, 

http://www.fws.gov/endangered/, http://www.fws.gov/southwest/es//NewMexico/, The

New Mexico Department of Game and Fish has a list of 120 endangered and threatened 

species found at: http://www.bison-m.org/

3. Socioeconomic and Cultural Resource Issues

New Mexico has many historic and recreation sites, and unique natural features throughout the 

state. Most of these occur on federal, state or tribal lands. The majority of these visitor sites and 

natural features are not found on rangeland, except with low frequency. Lava flow fields, 

geological landmarks and outcroppings, ancient archaeological sites, man-made reservoirs, 

lakes and dams, and historical ranch or church sites, and old military forts are sometimes visited 

within this rangeland environ.

Some county fair-grounds outside of town are located adjacent to rangelands; however, these

events occur in late summer or early autumn. Golf courses, racing tracks, rodeo arenas and 4-H
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livestock shows are located at the margins of towns and would be protected by the designated

program buffers.

Native American fiesta days and Colonial Hispanic ceremonies are not performed on rangeland,

but in towns and pueblos. Old abandoned community graveyards or “camposantos” and Indian 

burial grounds would be excluded as are heritage and historic, petroglyphs and pictographs sites

that are protected and preserved in the National Park Service areas or in New Mexico State parks 

and monuments. These ancestral cultural areas are under the protection of the federal 1906 

Antiquities Act and the 1965 National Heritage Act, and the NM State provisions with the 

Habitat Protection Act (NMSA 17-6-1 et seq.) and the Rangeland Protection Act (NMSA 76-

7B), and excluded from any APHIS grasshopper program.

5. Special Considerations for Certain Populations

a) Executive Order No. 12898, Federal Actions to Address Environmental Justice in 

Minority Populations and Low-Income Populations

Executive Order (E.O.) 12898, Federal Actions To Address Environmental Justice in Minority 

Populations and Low-Income Populations, was signed by President Clinton on February 11, 

1994 (59 Federal Register (FR) 7269). This E.O. requires each Federal agency to make 

achieving environmental justice part of its mission by identifying and addressing, as appropriate, 

disproportionately high and adverse human health or environmental effects of its programs, 

policies, and activities on minority populations and low-income populations. Consistent with this 

E.O., APHIS will consider the potential for disproportionately high and adverse human health or 

environmental effects on minority populations and low-income populations for any of its actions 

related to grasshopper suppression programs. 

b) Executive Order No. 13045, Protection of Children from Environmental Health 

Risks and Safety Risks

The increased scientific knowledge about the environmental health risks and safety risks 

associated with hazardous substance exposures to children and recognition of these issues in 

Congress and Federal agencies brought about legislation and other requirements to protect the 

health and safety of children. On April 21, 1997, President Clinton signed E.O. 13045, Protection 

of Children From Environmental Health Risks and Safety Risks (62 FR 19885). This E.O.

requires each Federal agency, consistent with its mission, to identify and assess environmental 

health risks and safety risks that may disproportionately affect children and to ensure that its 

policies, programs, activities, and standards address those risks. APHIS has developed agency 

guidance for its programs to follow to ensure the protection of children (USDA, APHIS, 1999). 

IV. Environmental Consequences

Each alternative described in this EA potentially has adverse environmental effects. The general 

environmental impacts of each alternative are discussed in detail in the 2002 and 2019 EIS. The 

specific impacts of the alternatives are highly dependent upon the particular action and location 

of infestation. The principal concerns associated with the alternatives are: (1) the potential effects 

of insecticides on human health (including subpopulations that might be at increased risk); and 
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(2) impacts of insecticides on nontarget organisms (including threatened and endangered 

species). 

APHIS has prepared human health and ecological risk assessments (HHERAs) to assess the 

insecticides and use patterns that are specific to the program. The risk assessments provide an indepth technical analysis of the potential impacts of each insecticide to human health; and nontarget fish and wildlife along with its environmental fate in soil, air, and water. The assessments 

rely on data required by the USEPA for pesticide product registrations, as well as peer-reviewed 

and other published literature. The HHERAs are incorporated by reference into the final EA. 

These Environmental Documents can be found at the following website:

http://www.aphis.usda.gov/plant-health/grasshopper. 

A. Environmental Consequences of the Alternatives

Site-specific environmental consequences of the alternatives are discussed in this section.

1. No Suppression Program Alternative

Under this alternative, APHIS would not conduct a program to suppress grasshoppers. If APHIS 

does not participate in any grasshopper suppression program, Federal land management 

agencies, State agriculture departments, local governments, private groups or individuals, may 

not effectively combat outbreaks in a coordinated effort. Without the technical assistance and 

coordination that APHIS provides during grasshopper outbreaks, the uncoordinated programs 

could use insecticides that APHIS considers too environmentally harsh. Multiple treatments and 

excessive amount of insecticide could be applied in efforts to suppress or even locally eradicate 

grasshopper populations. There are approximately 100 pesticide products registered by USEPA 

for use on rangelands and against grasshoppers (Purdue University, 2018). It is not possible to 

accurately predict the environmental consequences of the No Action alternative because the type 

and amount of insecticides that could be used in this scenario are unknown. However, the 

environmental impacts could be much greater than under the APHIS led suppression program 

alternative due to lack of treatment knowledge or coordination among the groups.

The potential environmental impacts from the No Action alternative, where other agencies and 

land managers do not control outbreaks, stem primarily from grasshoppers consuming vast 

amounts of vegetation in rangelands and surrounding areas. Grasshoppers are general feeders, 

eating grasses and forbs first and often moving to cultivated crops. High grasshopper density of 

one or several species and the resulting defoliation may reach an economic threshold where the 

damage caused by grasshoppers exceeds the cost of controlling the grasshoppers. Researchers 

determined that during typical grasshopper infestation years, approximately 20% of forage 

rangeland is removed, valued at a dollar adjusted amount of $900 million. This value represents 

32 to 63% of the total value of rangeland across the western states (Rashford et al., 2012). Other 

market and non-market values such as carbon sequestration, general ecosystem services, and 

recreational use may also be impacted by pest outbreaks in rangeland.

Vegetation damage during serious grasshopper outbreaks may be so severe that all grasses and 

forbs are destroyed; thus, plant growth is impaired for several years. Rare plants may be 

consumed during critical times of development such as seed production, and loss of important 

plant species, or seed production may lead to reduced diversity of rangeland habitats, potentially 
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creating opportunities for the expansion of invasive and exotic weeds (Lockwood and

Latchininsky, 2000). When grasshoppers consume plant cover, soil is more susceptible to the 

drying effects of the sun, making plant roots less capable of holding soil in place. Soil damage 

results in erosion and disruption of nutrient cycling, water infiltration, seed germination, and 

other ecological processes which are important components of rangeland ecosystems 

(Latchininsky et al., 2011).

When the density of grasshoppers reaches significantly high levels, grasshoppers begin to 

compete with livestock for food by reducing available forage (Wakeland and Shull, 1936; 

Belovsky, 2000; Pfadt, 2002; Branson et al., 2006; Bradshaw et al., 2018). Ranchers could offset 

some of the costs by leasing rangeland in another area and relocating their livestock, finding 

other means to feed their animals by purchasing hay or grain, or selling their livestock. Ranchers 

could also incur economic losses from personal attempts to control grasshopper damage. Local 

communities could see adverse economic impacts to the entire area. Grasshoppers that infest 

rangeland could move to surrounding croplands. Farmers could incur economic losses from 

attempts to chemically control grasshopper populations or due to the loss of their crops. The 

general public could see an increase in the cost of meat, crops, and their byproducts.

2. Insecticide Applications at Conventional Rates or Reduced Agent Area 

Treatments with Adaptive Management Strategy

Under Alternative 2, APHIS would participate in grasshopper programs with the option of using 

one of the insecticides carbaryl, diflubenzuron, or malathion, depending upon the various factors 

related to the grasshopper outbreak and the site-specific characteristics. The use of an insecticide 

would typically occur at half the conventional application rates following the RAATs strategy. 

APHIS would apply a single treatment to affected rangeland areas in an attempt to suppress 

grasshopper outbreak populations by a range of 35 to 98 percent, depending upon the insecticide 

used. 

a) Carbaryl

Carbaryl is a member of the N-methyl carbamate class of insecticides, which affect the nervous 

system via cholinesterase inhibition. Inhibiting the enzyme acetylcholinesterase (AChE) causes 

nervous system signals to persist longer than normal. While these effects are desired in 

controlling insects, they can have undesirable impacts to non-target organisms that are exposed. 

The APHIS HHERA assessed available laboratory studies regarding the toxicity of carbaryl on 

fish and wildlife. In summary, the document indicates the chemical is highly toxic to insects, 

including native bees, honeybees, and aquatic insects; slightly to highly toxic to fish; highly to 

very highly toxic to most aquatic crustaceans, moderately toxic to mammals, minimally toxic to 

birds; moderately to highly toxic to several terrestrial arthropod predators; and slightly to highly 

toxic to larval amphibians (USDA APHIS, 2018a). 

The offsite movement and deposition of carbaryl after treatments is unlikely because it does not

significantly vaporize from the soil, water, or treated surfaces (Dobroski et al., 1985).

Temperature, pH, light, oxygen, and the presence of microorganisms and organic material are 

factors that contribute to how quickly carbaryl will degrade in water. Hydrolysis, the breaking of 

a chemical bond with water, is the primary degradation pathway for carbaryl at pH 7 and above. 
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In natural water, carbaryl is expected to degrade faster than in laboratory settings due to the 

presence of microorganisms. The half-lives of carbaryl in natural waters varied between 0.3 to 

4.7 days (Stanley and Trial, 1980; Bonderenko et al., 2004). Degradation in the latter study was 

temperature dependent with shorter half-lives at higher temperatures. Aerobic aquatic 

metabolism of carbaryl reported half-life ranged of 4.9 to 8.3 days compared to anaerobic 

(without oxygen) aquatic metabolism range of 15.3 to 72 days (Thomson and Strachan, 1981; 

USEPA, 2003). Carbaryl is not persistent in soil due to multiple degradation pathways including 

hydrolysis, photolysis, and microbial metabolism. Little transport of carbaryl through runoff or 

leaching to groundwater is expected due to the low water solubility, moderate sorption, and rapid 

degradation in soils. There are no reports of carbaryl detection in groundwater, and less than 1% 

of granule carbaryl applied to a sloping plot was detected in runoff (Caro et al., 1974).

Acute and chronic risks to mammals are expected to be low to moderate based on the available 

toxicity data and conservative assumptions that were used to evaluate risk. There is the potential 

for impacts to small mammal populations that rely on terrestrial invertebrates for food. However, 

based on the toxicity data for terrestrial plants, minimal risks of indirect effects are expected to 

mammals that rely on plant material for food. Carbaryl has a reported half-life on vegetation of 

three to ten days, suggesting mammal exposure would be short-term. Direct risks to mammals 

from carbaryl bait applications is expected to be minimal based on oral, dermal, and inhalation 

studies (USDA APHIS, 2018a).

A number of studies have reported no effects on bird populations in areas treated with carbaryl 

(Buckner et al., 1973; Richmond et al., 1979; McEwen et al., 1996). Some applications of 

formulated carbaryl were found to cause depressed AChE levels (Zinkl et al., 1977; Gramlich, 

1979); however, the doses were twice those proposed for the full coverage application in the 

grasshopper program.

While sublethal effects have been noted in fish with depressed AChE, as well as some impacts to 

amphibians (i.e. days to metamorphosis) and aquatic invertebrates in the field due to carbaryl, 

the application rates and measured aquatic residues observed in these studies are well above 

values that would be expected from current program operations. Indirect risks to amphibian and 

fish species can occur through the loss of habitat or reduction in prey, yet data suggests that 

carbaryl risk to aquatic plants that may serve as habitat, or food, for fish and aquatic 

invertebrates is very low.

Product use restrictions appear on the USEPA-approved label and attempt to keep carbaryl out of 

waterways. Carbaryl must not be applied directly to water, or to areas where surface water is 

present (USEPA, 2012c). The USEPA-approved use rates and patterns and the additional 

mitigations imposed by the grasshopper program, such as using RAATs and application buffers, 

where applicable, further minimize aquatic exposure and risk.

The majority of rangeland plants require insect-mediated pollination. Native, solitary bee species 

are important pollinators on western rangeland (Tepedino, 1979). Potential negative effects of 

insecticides on pollinators are of concern because a decrease in their numbers has been 

associated with a decline in fruit and seed production of plants. Laboratory studies have 

indicated that bees are sensitive to carbaryl applications but the studies were at rates above those 

proposed in the program. The reduced rates of carbaryl used in the program and the 
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implementation of application buffers should significantly reduce exposure of pollinators to 

carbaryl applications. In areas of direct application where impacts may occur, alternating swaths 

and reduced rates (i.e., RAATs) would reduce risk. Potential negative effects of grasshopper 

program insecticides on bee populations may also be mitigated by the more common use of 

carbaryl baits than the ULV spray formulation. Studies with carbaryl bran bait have found no 

sublethal effects on adults or larvae bees (Peach et al., 1994, 1995).

Carbaryl can cause cholinesterase inhibition (i.e., overstimulate the nervous system) in humans 

resulting in nausea, headaches, dizziness, anxiety, and mental confusion, as well as convulsions, 

coma, and respiratory depression at high levels of exposure (NIH, 2009a; Beauvais, 2014). 

USEPA classifies carbaryl as “likely to be carcinogenic to humans” based on vascular tumors in 

mice (USEPA, 2007, 2015a, 2017a).

USEPA regulates the amount of pesticide residues that can remain in or on food or feed 

commodities as the result of a pesticide application. The agency does this by setting a tolerance, 

which is the maximum residue level of a pesticide, usually measured in parts per million (ppm), 

that can legally be present in food or feed. USEPA-registered carbaryl products used by the 

grasshopper program are labeled with rates and treatment intervals that are meant to protect 

livestock and keep chemical residues in cattle at acceptable levels (thereby protecting human 

health). While livestock and horses may graze on rangeland the same day that the land is 

sprayed, in order to keep tolerances to acceptable levels, carbaryl spray applications on 

rangeland are limited to half a pound active ingredient per acre per year (USEPA, 2012c). The 

grasshopper program would treat at or below use rates that appear on the label, as well as follow 

all appropriate label mitigations, which would ensure residues are below the tolerance levels.

Adverse human health effects from the proposed program ULV applications of the carbaryl 

spray (Sevin® XLR Plus) and bait applications of the carbaryl 5% and 2% baits formulations to 

control grasshoppers are not expected based on low potential for human exposure to carbaryl and 

the favorable environmental fate and effects data. Technical grade (approximately 100% of the 

insecticide product is composed of the active ingredient) carbaryl exhibits moderate acute oral 

toxicity in rats, low acute dermal toxicity in rabbits, and very low acute inhalation toxicity in 

rats. Technical carbaryl is not a primary eye or skin irritant in rabbits and is not a dermal 

sensitization in guinea pig (USEPA, 2007). This data can be extrapolated and applied to humans

revealing low health risks associated with carbaryl.

The Sevin® XLR Plus formulation, which contains a lower percent of the active ingredient than 

the technical grade formulation, is less toxic via the oral route, but is a mild irritant to eyes and 

skin. The proposed use of carbaryl as a ULV spray or a bait, use of RAATs, and adherence to 

label requirements, substantially reduces the potential for exposure to humans. Program workers 

are the most likely human population to be exposed. APHIS does not expect adverse health risks 

to workers based on low potential for exposure to carbaryl when applied according to label 

directions and use of personal protective equipment (PPE) (e.g., long-sleeved shirt and long 

pants, shoes plus socks, chemical-resistant gloves, and chemical-resistant apron) (USEPA, 

2012c) during loading and applications. APHIS quantified the potential health risks associated 

with accidental worker exposure to carbaryl during mixing, loading, and applications. The 

quantitative risk evaluation results indicate no concerns for adverse health risk for program 

workers (http://www.aphis.usda.gov/plant-health/grasshopper).
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Adherence to label requirements and additional program measures designed to reduce exposure 

to workers and the public (e.g., mitigations to protect water sources, mitigations to limit spray 

drift, and restricted-entry intervals) result in low health risk to all human population segments.

b) Diflubenzuron

Diflubenzuron is a restricted use pesticide (only certified applicators or persons under their direct 

supervision may make applications) registered with USEPA as an insect growth regulator. It 

specifically interferes with chitin synthesis, the formation of the insect’s exoskeleton. Larvae of 

affected insects are unable to molt properly. While this effect is desirable in controlling certain 

insects, it can have undesirable impacts to non-target organisms that are exposed.

USEPA considers diflubenzuron relatively non-persistent and immobile under normal use 

conditions and stable to hydrolysis and photolysis. The chemical is considered unlikely to 

contaminate ground water or surface water (USEPA, 1997). The vapor pressure of diflubenzuron 

is relatively low, as is the Henry’s Law Constant value, suggesting the chemical will not 

volatilize readily into the atmosphere from soil, plants or water. Therefore, exposure from 

volatilization is expected to be minimal. Due to its low solubility (0.2 mg/L) and preferential 

binding to organic matter, diflubenzuron seldom persists more than a few days in water 

(Schaefer and Dupras, 1977; Schaefer et al., 1980). Mobility and leachability of diflubenzuron in 

soils is low, and residues are usually not detectable after seven days (Eisler, 2000). Aerobic 

aquatic half-life data in water and sediment was reported as 26.0 days (USEPA, 1997). 

Diflubenzuron applied to foliage remains adsorbed to leaf surfaces for several weeks with little 

or no absorption or translocation from plant surfaces (Eisler, 1992, 2000). Diflubenzuron 

treatments are expected to have minimal effects on terrestrial plants. Both laboratory and field 

studies demonstrate no effects using diflubenzuron over a range of application rates, and the 

direct risk to terrestrial plants is expected to be minimal (USDA APHIS, 2018c).

Dimilin® 2L is labeled with rates and treatment intervals that are meant to protect livestock and 

keep residues in cattle at acceptable levels (thereby, protecting human health). Tolerances are set 

for the amount of diflubenzuron that is allowed in cattle fat (0.05 ppm) and meat (0.05 ppm) (40 

CFR Parts 180.377). The grasshopper program would treat at application rates indicated on 

product labels or lower, which should ensure approved residues levels. 

APHIS’ literature review found that on an acute basis, diflubenzuron is considered toxic to some 

aquatic invertebrates and practically non-toxic to adult honeybees. However, diflubenzuron is 

toxic to larval honeybees (USEPA, 2018). It is slightly nontoxic to practically nontoxic to fish 

and birds and has very slight acute oral toxicity to mammals, with the most sensitive endpoint 

from exposure being the occurrence of methemoglobinemia (a condition that impairs the ability 

of the blood to carry oxygen). Minimal direct risk to amphibians and reptiles is expected, 

although there is some uncertainty due to lack of information (USDA APHIS, 2018c; USEPA, 

2018).

Risk is low for most non-target species based on laboratory toxicity data, USEPA approved use 

rates and patterns, and additional mitigations such as the use of lower rates and RAATs that 

further reduces risk. Risk is greatest for sensitive terrestrial and aquatic invertebrates that may be 

exposed to diflubenzuron residues.
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In a review of mammalian field studies, Dimilin® applications at a rate of 60 to 280 g a.i./ha had 

no effects on the abundance and reproduction in voles, field mice, and shrews (USDA FS, 2004). 

These rates are approximately three to 16 times greater than the highest application rate proposed 

in the program. Potential indirect impacts from application of diflubenzuron on small mammals 

includes loss of habitat or food items. Mice on treated plots consumed fewer lepidopteran (order

of insects that includes butterflies and moths) larvae compared to controls; however, the total 

amount of food consumed did not differ between treated and untreated plots. Body 

measurements, weight, and fat content in mice collected from treated and non-treated areas did 

not differ. 

Poisoning of insectivorous birds by diflubenzuron after spraying in orchards at labeled rates is 

unlikely due to low toxicity (Muzzarelli, 1986). The primary concern for bird species is related 

to an indirect effect on insectivorous species from a decrease in insect prey. At the proposed 

application rates, grasshoppers have the highest risk of being impacted while other taxa have a 

much reduced risk because the lack of effects seen in multiple field studies on other taxa of 

invertebrates at use rates much higher than those proposed for the program. Shifting diets in 

insectivorous birds in response to prey densities is not uncommon in undisturbed areas 

(Rosenberg et al., 1982; Cooper et al., 1990; Sample et al., 1993).

Indirect risk to fish species can be defined as a loss of habitat or prey base that provides food and 

shelter for fish populations, however these impacts are not expected based on the available fish 

and invertebrate toxicity data (USDA APHIS, 2018c). A review of several aquatic field studies 

demonstrated that when effects were observed it was at diflubenzuron levels not expected from 

program activities (Fischer and Hall, 1992; USEPA, 1997; Eisler, 2000; USDA FS, 2004). 

Diflubenzuron applications have the potential to affect chitin production in various other 

beneficial terrestrial invertebrates. Multiple field studies in a variety of application settings, 

including grasshopper control, have been conducted regarding the impacts of diflubenzuron to 

terrestrial invertebrates. Based on the available data, sensitivity of terrestrial invertebrates to 

diflubenzuron is highly variable depending on which group of insects and which life stages are 

being exposed. Immature grasshoppers, beetle larvae, lepidopteran larvae, and chewing 

herbivorous insects appear to be more susceptible to diflubenzuron than other invertebrates. 

Diflubenzuron is also toxic to honeybee larvae. Within this group, however, grasshoppers 

appear to be more sensitive to the proposed use rates for the program. Honeybees, parasitic 

wasps, predatory insects, and sucking insects show greater tolerance to diflubenzuron exposure 

(Murphy et al., 1994; Eisler, 2000; USDA FS, 2004). 

Diflubenzuron is moderately toxic to spiders and mites (USDA APHIS, 2018c). Deakle and 

Bradley (1982) measured the effects of four diflubenzuron applications on predators of Heliothis

spp. at a rate of 0.06 lb a.i./ac and found no effects on several predator groups. This supported 

earlier studies by Keever et al. (1977) that demonstrated no effects on the arthropod predator 

community after multiple applications of diflubenzuron in cotton fields. Grasshopper integrated 

pest management (IPM) field studies have shown diflubenzuron to have a minimal impact on 

ants, spiders, predatory beetles, and scavenger beetles. There was no significant reduction in 

populations of these species from seven to 76 days after treatment. Although ant populations 

exhibited declines of up to 50 percent, these reductions were temporary, and population recovery 

was described as immediate (Catangui et al., 1996).
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Insecticide applications to rangelands have the potential to impact pollinators, and in turn, 

vegetation and various rangeland species that depend on pollinated vegetation. Based on the 

review of laboratory and field toxicity data for terrestrial invertebrates, applications of 

diflubenzuron are expected to have minimal risk to pollinators of terrestrial plants. The use of 

RAATs provide additional benefits by using reduced rates and creating untreated swaths within 

the spray block that will further reduce the potential risk to pollinators.

Adverse human health effects from ground or aerial ULV applications of diflubenzuron to 

control grasshoppers are not expected based on the low acute toxicity of diflubenzuron and low 

potential for human exposure. The adverse health effects of diflubenzuron to mammals and 

humans involves damage to hemoglobin in blood and the transport of oxygen. Diflubenzuron 

causes the formation of methemoglobin. Methemoglobin is a form of hemoglobin that is not able 

to transport oxygen (USDA FS, 2004). USEPA classifies diflubenzuron as non-carcinogenic to 

humans (USEPA, 2015b). 

Program workers adverse health risks are not likely when diflubenzuron is applied according to 

label directions that reduce or eliminate exposures. Adverse health risk to the general public in 

treatment areas is not expected due to the low potential for exposure resulting from low 

population density in the treatment areas, adherence to label requirements, program measures 

designed to reduce exposure to the public, and low toxicity to mammals.

c) Malathion

Malathion is a broad-spectrum organophosphate insecticide widely used in agriculture on various 

food and feed crops, homeowner yards, ornamental nursery stock, building perimeters, pastures 

and rangeland, and regional pest eradication programs. The chemical’s mode of action is through 

AChE inhibition, which disrupts nervous system function. While these effects are desired in 

controlling insects, they can have undesirable impacts to non-target organisms that are exposed 

to malathion. The grasshopper program currently uses the malathion end-use product Fyfanon®

ULV AG, applied as a spray by ground or air.

Volatility is not expected to be a major pathway of exposure based on the low vapor pressure and 

Henry’s Law constant that have been reported for malathion. The atmospheric vapor phase halflife of malathion is five hours (NIH, 2009b). Malathion’s half-life in pond, lake, river, and other 

natural waters varied from 0.5 days to ten days, depending on pH (Guerrant et al., 1970), 

persisting longer in acidic aquatic environments. The reported half-life in water and sediment for 

the anaerobic aquatic metabolism study was 2.5 days at a range of pH values from 7.8 to 8.7 

(USEPA, 2006). The persistence of malathion in soils depends primarily on microorganism 

activity, pH, and organic matter content. The persistence of malathion is decreased with 

microbial activity, moisture, and high pH (USEPA, 2016a) and the half-life of malathion in 

natural soil varies from two hours (Miles and Takashima, 1991) to 11 days (Neary, 1985; 

USEPA, 2006). 

Malathion and associated degradates, in general, are soluble and do not adsorb strongly to soils 

(USEPA, 2000a). Inorganic degradation of malathion may be more important in soils that are 

relatively dry, alkaline, and low in organic content, such as those that predominate in the western 

program areas. Adsorption to organic matter and rapid degradation make it unlikely that 

detectable quantities of malathion would leach to groundwater (LaFleur, 1979). Malathion 
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degradation products also have short half-lives. Malaoxon, the major malathion degradation 

product of toxicological concern, has half-lives less than one day in a variety of soil types 

(USEPA, 2016a). The half-life of malathion on foliage has been shown to range from one to six 

days (El-Refai and Hopkins, 1972; Nigg, 1986; Matsumara, 1985; USDA FS, 2008).

While livestock and horses may graze on rangeland the same day that the land is treated with 

malathion, the products used by the grasshopper program are labeled with rates and treatment 

intervals that are meant to protect livestock. Tolerances are set for the amount of malathion that 

is allowed in cattle fat (4 ppm), meat (4 ppm), and meat byproducts (4 ppm) (40 CFR Parts 

180.111). The grasshopper program would treat at application rates indicated on product labels 

or lower, which would ensure approved residues levels. In addition, the program would make 

only one application a year.

USEPA found malathion moderately toxic to birds on a chronic basis, slightly toxic to mammals 

through dietary exposure, and acutely toxic to aquatic species (including freshwater as well as 

estuarine and marine species) (USEPA, 2000b, 2016b). Toxicity to aquatic vertebrates such as 

fish and larval amphibians, and aquatic invertebrates is variable based on test species and 

conditions. The data available on impacts to fish from malathion suggest effects could occur at 

levels above those expected from program applications. Consumption of contaminated prey is 

not expected to be a significant pathway of exposure for aquatic species based on expected 

residues and malathion’s BCF (USEPA, 2016a; USDA APHIS, 2018d). Indirect effects to fish 

from impacts of malathion applications to aquatic plants are not expected (USDA APHIS, 

2018d).

USEPA considers malathion highly toxic to bees if exposed to direct treatment on blooming 

crops or weeds. The Fyfanon® ULV AG label indicates not to apply product or allow it to drift to 

blooming crops or weeds while bees are actively visiting the treatment area (USEPA, 2012a). 

Toxicity to other terrestrial invertebrates is variable based on the test organism and test 

conditions however malathion is considered toxic to most terrestrial invertebrates (USEPA, 

2016b).

Indirect risks to mammals resulting from the loss of plants that serve as a food source would also 

be low due to the low phytotoxicity of malathion. The other possible indirect effect that should 

be considered is loss of invertebrate prey for those mammals that depend on insects and other 

invertebrates as a food source. Insects have a wide variety of sensitivities to malathion and a 

complete loss of invertebrates from a treated area is not expected because of low program rates 

and application techniques. In addition, the aerial and ground application buffers and untreated 

swaths provide refuge for invertebrates that serve as prey for insectivorous mammals and would 

expedite repopulation of areas that may have been treated.

APHIS expects that direct avian acute and chronic effects would be minimal for most species 

(USDA APHIS, 2018d). The preferred use of RAATs during application reduces these risks by 

reducing residues on treated food items and reducing the probability that they will only feed on 

contaminated food items. In addition, malathion degrades quickly in the environment and 

residues on food items are not expected to persist. Indirect effects on birds from the loss of 

habitat and food items are not expected because of malathion’s low toxicity to plants and the 

implementation of RAATs that would reduce the potential impacts to invertebrates that serve as 
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prey for avian species. Several field studies did not find significant indirect effects of malathion 

applications on avian fecundity (Dinkins et al., 2002; George et al., 1995; Howe, 1993; Howe et 

al., 1996; Norelius and Lockwood, 1999; Pascual, 1994).

Available toxicity data demonstrates that amphibians are less sensitive to malathion than fish. 

Program malathion residues are more than 560 times below the most sensitive acute toxicity 

value for amphibians. Sublethal effects, such as developmental delays, reduced food 

consumption and body weight, and teratogenesis (developmental defects that occur during 

embryonic or fetal growth), have been observed at levels well above those assessed from the 

program’s use of malathion (USDA APHIS, 2018d). Program protection measures for aquatic 

water bodies and the available toxicity data for fish, aquatic invertebrates, and plants suggest low 

indirect risks related to reductions in habitat or aquatic prey items from malathion treatments.

Available data on malathion reptile toxicity suggest that, with the use of program measures, no 

lethal or sublethal impacts would be anticipated (USDA APHIS, 2015). Indirect risk to reptiles 

from the loss of food items is expected to be low due to the low application rates and 

implementation of preferred program measures such as RAATs (USDA APHIS, 2018d).

The risk to aquatic vertebrates and invertebrates is low for most species; however, some sensitive 

species that occur in shallow water habitats may be at risk. Program measures such application 

buffer zones, drift mitigation measures and the use of RAATs will reduce these risks.

Risks to terrestrial invertebrate populations are anticipated based on the available toxicity data 

for invertebrates and the broad spectrum activity of malathion (Swain, 1986; Quinn et al., 1991). 

The risk to terrestrial invertebrates can be reduced by the implementation of application buffers 

and the use of RAATs, which would reduce exposure and create refuge areas where malathion 

impacts would be reduced or eliminated. Smith et al. (2006) conducted field studies to evaluate 

the impacts of grasshopper treatments to non-target terrestrial invertebrates and found minimal 

impacts when making reduced rate applications with a reduced coverage area (i.e. RAATs) for a 

ULV end-use product of malathion. Impacts to pollinators have the potential to be significant, 

based on available toxicity data for honeybees that demonstrate high contact toxicity from 

malathion exposures (USDA APHIS, 2018d). However, risk to pollinators is reduced because of 

the short residual toxicity of malathion. In addition, the incorporation of other mitigation 

measures in the program, such as the use of RAATs and wind speed and direction mitigations 

that are designed to minimize exposure, reduce the potential for population-level impacts to 

terrestrial invertebrates.

Adverse human health effects from ULV applications of malathion to control grasshopper are 

not expected based on the low mammalian acute toxicity of malathion and low potential for 

human exposure. Malathion inhibits AChE in the central and peripheral nervous system with 

clinical signs of neurotoxicity that include tremors, salivation, urogenital staining, and decreased 

motor activity. USEPA indicates that malathion has “suggestive evidence of carcinogenicity but 

not sufficient to assess human carcinogenic potential” (USEPA, 2016c). 

Adverse health risks to program workers and the general public from malathion exposure are 

also not expected due to low potential for exposure. APHIS treatments are conducted in 

rangeland areas consisting of widely scattered, single, rural dwellings in ranching communities, 
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where agriculture is a primary industry. Label requirements to reduce exposure include 

minimizing spray drift, avoidance of water bodies and restricted entry interval. Program 

measures such as applying malathion once per season, lower application rates, application 

buffers and other measures further reduce the potential for exposure to the public.

d) Reduced Area Agent Treatments (RAATs) 

The use of RAATS is the most common application method for all program insecticides and 

would continue to be so accept in rare pest conditions that warrant full coverage and higher rates. 

The goal of the RAATs strategy is to suppress grasshopper populations to a desired level, rather 

than to reduce those populations to the greatest possible extent. This strategy has both economic 

and environmental benefits. APHIS would apply a single application of insecticide per year, 

typically using a RAATs strategy that decreases the rate of insecticide applied by either using 

lower insecticide concentrations, or by alternating one or more treatment swaths. Usually 

RAATs applications use both options. The RAATs strategy suppresses grasshoppers within 

treated swaths, while conserving grasshopper predators and parasites in swaths that are not 

treated. 

The concept of reducing the treatment area of insecticides while also applying less insecticide 

per treated acre was developed in 1995, with the first field tests of RAATs in Wyoming 

(Lockwood and Schell, 1997). Applications can be made either aerially or with ground-based 

equipment (Deneke and Keyser, 2011). Studies using the RAATs strategy have shown good 

control (up to 85% of that achieved with a traditional blanket insecticide application) at a 

significantly lower cost and less insecticide, and with a markedly higher abundance of non-target 

organisms following application (Lockwood et al., 2000; Deneke and Keyser, 2011). Levels of 

control may also depend on variables such as body size of targeted grasshoppers, growth rate of 

forage, and the amount of coverage obtained by the spray applications (Deneke and Keyser, 

2011). Control rates may also be augmented by the necrophilic and necrophagic behavior of 

grasshoppers, in which grasshoppers are attracted to volatile fatty acids emanating from cadavers 

of dead grasshoppers and move into treated swaths to cannibalize cadavers (Lockwood et al., 

2002; Smith and Lockwood, 2003). Under optimal conditions, RAATs decrease control costs, as 

well as host plant losses and environmental effects (Lockwood et al., 2000; Lockwood et al., 

2002). 

The efficacy of a RAATs strategy in reducing grasshoppers is, therefore, less than conventional 

treatments and more variable. Foster et al. (2000) reported that grasshopper mortality using 

RAATs was reduced 2 to 15% from conventional treatments, depending on the insecticide, while 

Lockwood et al. (2000) reported 0 to 26% difference in mortality between conventional and 

RAATs methods. APHIS will consider the effects of not suppressing grasshoppers to the greatest 

extent possible as part of the treatment planning process. 

RAATs reduces treatment costs and conserves non-target biological resources in untreated areas. 

The potential economic advantages of RAATs was proposed by Larsen and Foster (1996), and 

empirically demonstrated by Lockwood and Schell (1997). Widespread efforts to communicate 

the advantages of RAATs across the Western States were undertaken in 1998, and have 

continued on an annual basis. The viability of RAATs at an operational scale was initially 

demonstrated by Lockwood et al. (2000), and subsequently confirmed by Foster et al. (2000). 

The first government agencies to adopt RAATs in their grasshopper suppression programs were 
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the Platte and Goshen County Weed and Pest Districts in Wyoming; they also funded research at 

the University of Wyoming to support the initial studies in 1995. This method is now commonly 

used by government agencies and private landowners in States where grasshopper control is 

required.

Reduced rates should prove beneficial for the environment. All APHIS grasshopper treatments 

using carbaryl, diflubenzuron, or malathion are conducted in adherence with USEPA-approved 

label directions. Labeled application rates for grasshopper control tend to be lower than rates 

used against other pests. In addition, use rates proposed for grasshopper control by APHIS are 

lower than rates used by private landowners.

B. Other Environmental Considerations

1. Cumulative Impacts

Cumulative impact, as defined in the Council on Environmental Quality (CEQ) NEPA 

implementing regulations (40 CFR § 1508.7) “is the impact on the environment which results 

from the incremental impact of the action when added to the past, present, and reasonably 

foreseeable future actions regardless of what agency (Federal or non-Federal) or person 

undertakes such actions. Cumulative impacts can result from individually minor but collectively 

significant actions taking place over a period of time.”

Potential cumulative impacts associated with the No Action alternative where APHIS would not 

take part in any grasshopper suppression program include the continued increase in grasshopper 

populations and potential expansion of populations into neighboring range and cropland. In 

addition, State and private land managers could apply insecticides to manage grasshopper 

populations however, land managers may opt not to use RAATs, which would increase 

insecticides applied to the environment. Increased insecticide use from the lack of coordination 

and RAAT applications where suitable could increase the exposure risk to non-target species and 

the environment. In addition, land managers may not employ the extra program measures 

designed to reduce exposure to the public and the environment. 

Potential cumulative impacts associated with the Preferred Alternative are not expected to be 

significant because the program applies an insecticide application once during a treatment. The 

program may treat an area with different insecticides, but does not overlap the treatments. The 

program does not mix or combine insecticides on suppression treatments. However, this may not 

be the case for experimental treatments. Based on historical outbreaks in the United States, the 

probability of an outbreak occurring in the same area where treatment occurred in the previous 

year is unlikely; however, given time, populations eventually will reach economically damaging 

thresholds and require treatment. The insecticide application reduces the insect population down 

to levels that cause an acceptable level of economic damage. The duration of treatment activity, 

which is relatively short since it is a one-time application, and the lack of repeated treatments in 

the same area in the same year reduce the possibility of significant cumulative impacts.

Potential cumulative impacts resulting from the use of insecticides include insect pest resistance, 

synergistic chemical effects, chemical persistence and bioaccumulation in the environment. The 

program use of reduced insecticide application rates (i.e. ULV and RAATs) are expected to 

mitigate the development of insect resistance to the insecticides. Grasshopper outbreaks in the 
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United States occur cyclically so applications do not occur to the same population over time 

further eliminating the selection pressure increasing the chances of insecticide resistance.

The insecticides proposed for use in the program have a variety of agricultural and nonagricultural uses. There may be an increased use of these insecticides in an area under 

suppression when private, State, or Federal entities make applications to control other pests. 

However, the vast majority of the land where program treatments occur is uncultivated rangeland 

and additional treatments by land owners or managers are very uncommon making possible 

cumulative or synergistic chemical effects extremely unlikely. 

The insecticides proposed for use in the grasshopper program are not anticipated to persist in the 

environment or bioaccumulate. Therefore, a grasshopper outbreak that occurs in an area 

previously treated for grasshoppers is unlikely to cause an accumulation of insecticides from 

previous program treatments.

The proposed experimental treatments are short-term and would take place in a very limited area. 

The purpose of the field tests conducted by the Rangeland Unit will help determine whether 

APHIS would eventually include Metarhizium robertsii (isolate DWR2009) based biopesticides

as an option for the Program. The data generated by these studies would likely be used as part of 

the EPA registration process for this biopesticide. Inclusion of effective and environmentally 

friendly insecticides would provide the Program additional control options for grasshoppers and 

Mormon crickets in sensitive habitats. If successful, the use of M. robertsii could decrease the 

amount of chemical insecticides used in rangeland against grasshoppers and Mormon crickets

2. Executive Order No. 12898, Federal Actions to Address Environmental

Justice in Minority Populations and Low-Income Populations

Federal agencies identify and address the disproportionately high and adverse human health or 

environmental effects of their proposed activities, as described in E.O. 12898, “Federal Actions 

to Address Environmental Justice in Minority Populations and Low-Income Populations.”

3. Executive Order No. 13045, Protection of Children from Environmental

Health Risks and Safety Risks

Federal agencies consider a proposed action’s potential effects on children to comply with E.O.

13045, “Protection of Children from Environmental Health Risks and Safety Risks.” This E.O.

requires each Federal agency, consistent with its mission, to identify and assess environmental 

health and safety risks that may disproportionately affect children and to ensure its policies, 

programs, activities, and standards address disproportionate risks to children that result from 

environmental health risks or safety risks. APHIS has developed agency guidance for its 

programs to follow to ensure the protection of children (USDA APHIS, 1999).

APHIS’ HHERAs evaluated the potential exposure to each insecticide used in the program and 

risks associated with these insecticides to residents, including children. The HHERAs for the 

proposed program insecticides, located at http://www.aphis.usda.gov/plant-health/grasshopper, 

suggest that no disproportionate risks to children, as part of the general public, are anticipated.

APHIS grasshopper insecticide treatments are conducted in rural rangeland areas, where 

agriculture is a primary industry. The areas consist of widely scattered, single, rural dwellings in 
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ranching communities with low population density. The program notifies residents within 

treatment areas, or their designated representatives, prior to proposed operations to reduce the 

potential for incidental exposure to residents including children. Treatments are conducted 

primarily on open rangelands where children would not be expected to be present during 

treatment or to enter should there be any restricted entry period after treatment. The program also 

implements mitigation measures beyond label requirements to ensure that no treatments occur 

within the required buffer zones from structures, such as a 500-foot treatment buffer zone from

schools and recreational areas. Program insecticides are not applied while school buses are 

operating in the treatment area.

4. Tribal Consultation

Executive Order 13175 "Consultation and Coordination with Indian Tribal Governments," calls 

for agency communication and collaboration with tribal officials when proposed Federal actions 

have potential tribal implications. The Archaeological Resources Protection Act of 1979 (16 

U.S.C. §§ 470aa-mm), secures the protection of archaeological resources and sites on public and 

tribal lands.

Prior to the treatment season, program personnel notify Tribal land managers of the potential for 

grasshopper and Mormon cricket outbreaks on their lands. Consultation with local Tribal 

representatives takes place prior to treatment programs to inform fully the Tribes of possible 

actions APHIS may take on Tribal lands. No Program treatments are made without a request and 

from Tribal land managers. Treatments typically do not occur at cultural sites, and drift from a 

program treatment at such locations is not expected to adversely affect natural surfaces, such as 

rock formations and carvings. APHIS would also confer with the appropriate Tribal authority to 

ensure that the timing and location of a planned program treatment does not coincide or conflict 

with cultural events or observances on Tribal lands.

5. Executive Order 13186, Responsibilities of Federal Agencies to Protect 

Migratory Birds

The Migratory Bird Treaty Act (MBTA) of 1918 (16 U.S.C. 703–712) established a Federal 

prohibition, unless permitted by regulations, to pursue, hunt, take, capture, kill, attempt to take, 

capture or kill, possess, offer for sale, sell, offer to purchase, purchase, deliver for shipment, 

ship, cause to be shipped, deliver for transportation, transport, cause to be transported, carry, or 

cause to be carried by any means whatever, receive for shipment, transportation or carriage, or 

export, at any time, or in any manner, any migratory bird or any part, nest, or egg of any such 

bird.

APHIS will support the conservation intent of the migratory bird conventions by integrating bird 

conservation principles, measures, and practices into agency activities and by avoiding or 

minimizing, to the extent practicable, adverse impacts on migratory bird resources when 

conducting agency actions. Impacts are minimized as a result of buffers to water, habitat, nesting 

areas, riparian areas, and the use of RAATs. For any given treatment, only a portion of the 

environment will be treated, therefore minimizing potential impacts to migratory birds. 
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6. Endangered Species Act

Section 7 of the Endangered Species Act (ESA) and its implementing regulations require Federal 

agencies to ensure their actions are not likely to jeopardize the continued existence of listed 

threatened or endangered (listed) species, or result in the destruction or adverse modification of 

critical habitat. Numerous federally-listed species and areas of designated critical habitat occur 

within the 17-State program area, although not all occur within or near potential grasshopper 

suppression areas or within the area under consideration by through this EA. 

APHIS considers whether listed species, species proposed for listing, experimental populations, 

or critical habitat are present in the proposed suppression area. Before treatments are conducted, 

APHIS contacts the U.S Fish and Wildlife Service (USFWS) or the National Marine Fisheries 

Service (NMFS) (where applicable) to determine if listed species are present in the suppression 

area, and whether mitigations or protection measures must be implemented to protect listed 

species or critical habitat. 

APHIS has completed consultation for Federally-listed species in New Mexico. No APHIS 

treatments are made in States without prior concurrence from the FWS regarding Federally-listed 

species. APHIS consulted with the FWS on Federally listed species that may occur within the 

county or areas where grasshopper and Mormon cricket treatments may be required. APHIS 

works closely with the FWS to determine the application of protection measures and where those 

measures should be applied prior to any treatments. A copy of the letter of concurrence is

included in Appendix D. 

APHIS has also submitted a programmatic biological assessment and requested consultation with 

USFWS on March 9, 2015 for use of carbaryl, malathion, diflubenzuron, and chlorantraniliprole 

for grasshopper suppression in the 17-state program area. With the incorporation and use of 

application buffers and other operational procedures APHIS anticipates that any impacts 

associated with the use and fate of program insecticides will be insignificant and discountable to 

listed species and their habitats. Based on an assessment of the potential exposure, response, and 

subsequent risk characterization of program operations, APHIS concludes the proposed action is 

not likely to adversely affect listed species or critical habitat in the program area. APHIS has 

requested concurrence from the USFWS on these determinations. Until this programmatic 

Section 7 consultation with USFWS is completed, APHIS will conduct consultations with 

USFWS field offices at the local level.

7. Bald and Golden Eagle Protection Act

The Bald and Golden Eagle Protection Act (16 U.S.C. 668–668c) prohibits anyone, without a 

permit issued by the Secretary of the Interior, from “taking” bald eagles, including their parts, 

nests, or eggs. During the breeding season, bald eagles are sensitive to a variety of human 

activities. Grasshopper management activities could cause disturbance of nesting eagles, 

depending on the duration, noise levels, extent of the area affected by the activity, prior 

experiences that eagles have with humans, and tolerance of the individual nesting pair. Also, 

disruptive activities in or near eagle foraging areas can interfere with bald eagle feeding, 

reducing chances of survival. USFWS has provided recommendations for avoiding disturbance 

at foraging areas and communal roost sites that are applicable to grasshopper management 

programs (USFWS, 2007).
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No toxic effects are anticipated on eagles as a direct consequence of insecticide treatments. 

Toxic effects on the principle food source, fish, are not expected because insecticide treatments 

will not be conducted over rivers or lakes. Buffers protective of aquatic biota are applied to their 

habitats to ensure that there are no indirect effects from loss of prey.

8. Additional Species of Concern

There may be species that are of special concern to land management agencies, the public, or 

other groups and individuals in proposed treatment areas. For example, the sage grouse 

populations have declined throughout most of their entire range, with habitat loss being a major 

factor in their decline.

Grasshopper suppression programs reduce grasshoppers and at least some other insects in the 

treatment area that can be a food item for sage grouse chicks. As indicated in previous sections 

on impacts to birds, there is low potential that the program insecticides would be toxic to sage 

grouse, either by direct exposure to the insecticides or indirectly through immature sage grouse 

eating moribund grasshoppers. 

Because grasshopper numbers are so high in an outbreak year, treatments would not likely 

reduce the number of grasshoppers below levels present in a normal year. Should grasshoppers 

be unavailable in small, localized areas, sage grouse chicks may consume other insects, which 

sage grouse chicks likely do in years when grasshopper numbers are naturally low. By 

suppressing grasshoppers, rangeland vegetation is available for use by other species, including 

sage grouse, and rangeland areas are less susceptible to invasive plants that may be undesirable 

for sage grouse habitat.

9. Fires and Human Health Hazards

Various compounds are released in smoke during wildland fires, including carbon monoxide 

(CO), carbon dioxide, nitrous oxides, sulfur dioxide, hydrogen chloride, aerosols, polynuclear 

aromatic hydrocarbons contained within fine particulate matter (a byproduct of the combustion 

of organic matter such as wood), aldehydes, and most notably formaldehyde produced from the 

incomplete combustion of burning biomass (Reisen and Brown, 2009; Burling et al., 2010; 

Broyles, 2013). Particulate matter, CO, benzene, acrolein, and formaldehyde have been 

identified as compounds of particular concern in wildland fire smoke (Reinhardt and Ottmar, 

2004). 

Many of the naturally occurring products associated with combustion from wildfires may also be 

present as a result of combustion of program insecticides that are applied to rangeland. These 

combustion byproducts will be at lower quantities due to the short half-lives of most of the 

program insecticides and their low use rates. Other minor combustion products specific to each 

insecticide may also be present as a result of combustion from a rangeland fire but these are 

typically less toxic based on available human health data (http://www.aphis.usda.gov/planthealth/grasshopper).

The safety data sheet for each insecticide identifies these combustion products for each 

insecticide as well as recommendations for personal protective equipment (PPE). The PPE is

similar to what typically is used in fighting wildfires. Material applied in the field will be at a 

much lower concentration than what would occur in a fire involving a concentrated formulation.
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29

Therefore the PPE worn by rangeland firefighters would also be protective of any additional 

exposure resulting from the burning of residual insecticides. 

10. Cultural and Historical Resources

Federal actions must seek to avoid, minimize, and mitigate potential negative impacts to cultural 

and historic resources as part of compliance with the National Historic Preservation Act 

(NHPA), the Archaeological Resources Protection Act of 1979, and NEPA. Section 106 of the 

NHPA requires Federal agencies to provide the Advisory Council on Historic Preservation with 

an opportunity to comment on their findings.

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Pascual, J. A. 1994. No effects of a forest spraying of malathion on breeding blue tits (Parus 

caeruleus). Environ. Toxicol. Chem. 13:1127–1131.

Peach, M. P., D. G. Alston, and V. J. Tepedino. 1994. Bees and bran bait: is carbaryl bran bait 

lethal to alfalfa leafcutting bee (Hymenoptera: Megachilidae) adults or larvae? J. Econ. 

Entomol. 87:311-317.

Peach, M. P., D. G. Alston, and V. J. Tepedino. 1995. Subleathal effects of carbaryl bran bait on 

nesting performance, parental investment, and offspring size and sex ratio of the alfalfa 

leafcutting bee (Hymenoptera: Megachilidae). Environ. Entomol. 24:34-39.

Pfadt, R. E. 2002. Field Guide to Common Western Grasshoppers, Third Edition. Wyoming 

Agricultural Experiment Station Bulletin 912. Laramie, Wyoming.

Purdue University. 2018. National Pesticide Information Retrieval System. West Lafayette, IN.

Quinn, M. A., R. L. Kepner, D. D. Walgenbach, R. N. Foster, R. A. Bohls, P. D. Pooler, K. C. 

Reuter, and J. L. Swain. 1991. Effect of habitat and perturbation on populations and 

community structure of darkling beetles (Coleoptera: tenebrionidae) on mixed grass 

rangeland. Environ. Entomol. 19:1746-1755.

Rashford, B. S., A. V. Latchininsky, and J. P. Ritten. 2012. An Economic Analysis of the 

Comprehensive Uses of Western Rangelands. U.S. Department of Agriculture, Animal 

and Plant Health Inspection Service.

Reinhardt, T. and R. Ottmar. 2004. Baseline measurements of smoke exposure among wildland 

firefighters. Journal of Occupational and Environmental Hygiene 1:593-606.

Reisen, F. and S. Brown. 2009. Australian firefighters' exposure to air toxics during bushfire 

burns of autumn 2005 and 2006. Environment International 35:342-353.

Richmond, M. L., C. J. Henny, R. L. Floyd, R. W. Mannan, D. W. Finch, and L. R. DeWeese. 

1979. Effects of Sevin 4-oil, Dimilin, and Orthene on Forest Birds in Northeastern 

Oregon. USDA, Pacific SW Forest and Range Experiment Station.

Rosenberg, K. V., R. D. Ohmart, and B. W. Anderson. 1982. Community organization of 

riparian breeding birds: response to an annual resource peak. The Auk 99:260-274.

Sample, B. E., R. J. Cooper, and R. C. Whitmore. 1993. Dietary shifts among songbirds from a 

diflubenzuron-treated forest. The Condor 95:616-624.
`

33

Schaefer, C. H., A. E. Colwell, and E. F. Dupras, Jr. 1980. The occurrence of p-chloroaniline and 

p-c hlorophenylurea from the degradation of pesticide in water and fish. Proceedings of 

the 48th Ann. Meeting Mosquito Vector Cont. Assoc.:84-89.

Schaefer, C. H. and E. F. Dupras, Jr. 1977. Residues of diflubenzuron [1-(4-chlorophenyl)-3(2,6-

difluorobenzoyl) urea] in pasture soil, vegetation, and water following aerial applications. 

J. Agric. Food Chem. 25:1026-1030.

Smith, D. and J. Lockwood. 2003. Horizontal and trophic transfer of diflubenzuron and fipronil 

among grasshoppers and between grasshoppers and darkling beetles (Tenebrionidae). 

Archives of Environmental Contamination and Toxicology 44:377-382.

Smith, D. I., J. A. Lockwood, A. V. Latchininsky, and D. E. Legg. 2006. Changes in non-target 

populations following applications of liquid bait formulations of insecticides for control 

of rangeland grasshoppers. Internat. J. Pest Mgt. 52:125-139.

Stanley, J. G. and J. G. Trial. 1980. Disappearance constants of carbaryl from streams 

contaminated by forest spraying. Bul. Environ. Contam. Toxicol. 25:771-776.

Swain, J. L. 1986. Effect of Chemical Grasshopper Controls on Non-Target Arthropods of 

Rangeland in Chaves County, New Mexico. New Mexico State University.

Tepedino, V. J. 1979. The importance of bees and other insect planetaries in maintaining floral 

species composition. Great Basin Naturalist Memoirs 3:139-150.

Thomson, D. L. K. and W. M. J. Strachan. 1981. Biodegradation of carbaryl in simulated aquatic 

environment. Bul. Environ. Contam. Toxicol. 27:412-417.

USDA APHIS– see U.S. Department of Agriculture, Animal and Plant Health Inspection Service

U.S. Department of Agriculture, Animal and Plant Health Inspection Service, 1999. APHIS 

Directive 5600.3, Evaluating APHIS programs and activities for ensuring protection of 

children from environmental health risks and safety risks. September 3, 1999. U.S. 

Department of Agriculture, Animal and Plant Health Inspection Service, Riverdale, MD. 

[online] available: http://www.aphis.usda.gov/library/directives.

U.S. Department of Agriculture, Animal and Plant Health Inspection Service. 2015. Biological 

Assessment for the APHIS Rangeland Grasshopper and Mormon Cricket Suppression 

Program. Page 162. U.S. Department of Agriculture, Animal and Plant Health Inspection 

Service.

U.S. Department of Agriculture, Animal and Plant Health Inspection Service. 2018a. Human 

Health and Ecological Risk Assessment for Carbaryl Rangeland Grasshopper and 

Mormon Cricket Suppression Applications. United States Department of Agriculture, 

Animal and Plant Health Inspection Service.

U.S. Department of Agriculture, Animal and Plant Health Inspection Service. 2018c. Human 

Health and Ecological Risk Assessment for Diflubenzuron Rangeland Grasshopper and 

Mormon Cricket Suppression Applications. United States Department of Agriculture, 

Animal and Plant Health Inspection Service.

U.S. Department of Agriculture, Animal and Plant Health Inspection Service. 2018d. Human 

Health and Ecological Risk Assessment for Malathion Rangeland Grasshopper and 

Mormon Cricket Suppression Applications. United States Department of Agriculture, 

Animal and Plant Health Inspection Service.

U.S. Department of Agriculture, Animal and Plant Health Inspection Service. 2019. Rangeland 

Grasshopper and Mormon Cricket Suppression Program Final Environmental Impact 

Statement. United States Department of Agriculture, Animal and Plant Health Inspection 

Service.
`

34

USDA FS. 2004. Control/eradication agents for the gypsy moth—human health and ecological 

risk assessment for diflubenzuron (final report). United States Department of Agriculture, 

Forest Service

USDA FS. 2008. Malathion- Human Health and Ecological Risk Assessment. U.S. Department 

of Agriculture, Forest Service.

USEPA – See U.S. Environmental Protection Agency

U.S. Environmental Protection Agency. 1997. Reregistration Eligibility Decision (RED): 

Diflubenzuron. U.S. Environmental Protection Agency.

U.S. Environmental Protection Agency. 2000a. Malathion Reregistration Eligibility Document 

Environmental Fate and Effects. Page 146. U.S. Environmental Protection Agency, 

Office of Prevention, Pesticides and Toxic Substances.

U.S. Environmental Protection Agency. 2000b. Reregistration Eligibility Decision (RED) for 

Malathion. U.S. Environmental Protection Agency.

USEPA. 2003. Environmental Fate and Ecological Risk Assessment for Re-Registration of 

Carbaryl. U.S. Environmental Protection Agency.

U.S. Environmental Protection Agency. 2006. Malathion Reregistration Eligibility Document. 

Page 147. U.S. Environmental Protection Agency, Office of Pesticide Programs.

U.S. Environmental Protection Agency. 2007. Reregistration Eligibility Decision (RED) for 

Carbaryl. Page 47. U.S. Environmental Protection Agency, Prevention, Pesticides and 

Toxic Substances.

U.S. Environmental Protection Agency. 2012a. Fyfanon ULV AG. U.S. Environmental 

Protection Agency.

U.S. Environmental Protection Agency. 2012c. Sevin XLR Plus Label. Pages 1-40 Pesticide 

Product and Label System. U.S. Environmental Protection Agency.

U.S. Environmental Protection Agency. 2015a. Annual Cancer Report 2015, Chemicals 

Evaluated for Carcinogenic Potential Page 34. U.S. Environmental Protection Agency, 

Office of Pesticide Programs.

U.S. Environmental Protection Agency. 2015b. Memorandum - Diflubenzuron: human health 

risk assessment for an amended Section 3 registration for carrot, peach subgroup 12-12B, 

plum subgroup 12-12C, pepper/eggplant subgroup 8010B, cottonseed subgroup 20C, 

alfalfa (regional restrictions) and R175 Crop Group Conversion for tree nut group 14-12. 

Page 71 U.S. Environmental Protection Agency, Office of Pesticide Programs.

U.S. Environmental Protection Agency. 2016a. Appendix 3-1: Environmental transport and fate 

data analysis for malathion. In: Biological Evaluation Chapters for Malathion ESA 

Assessment.

U.S. Environmental Protection Agency. 2016b. Chapter 2: Malathion Effects Characterization 

for ESA Assessment. In: Biological Evaluation Chapters for Malathion ESA Assessment.

U.S. Environmental Protection Agency. 2016c. Malathion: Human Health Draft Risk 

Assessment for Registration Review. Page 258. U.S. Environmental Protection Agency.

U.S. Environmental Protection Agency. 2017a. Memorandum - Carbaryl: Draft Human Health 

Risk Assessment in Support of Registration Review. Page 113 U.S. Environmental 

Protection Agency.

U.S. Environmental Protection Agency. 2017b. Prevathon Label. U.S. Environmental Protection 

Agency.

U.S. Environmental Protection Agency. 2018. Preliminary Risk Assessment to Support the 

Registration Review of Diflubenzuron.
`

35

USFWS. 2007. National Bald Eagle Management Guidelines. Page 23 pp. U.S. Fish and Wildlife 

Service.

Wakeland, C. and W. E. Shull. 1936. The Mormon cricket with suggestions for its control, 

Extension Bulletin No. 100. University of Idaho, College of Agriculture, Idaho 

Agricultural Extension.

Zinkl, J. G., C. J. Henny, and L. R. DeWeese. 1977. Brain cholinesterase activities of birds from 

forests sprayed with trichlorfon (Dylox) and carbaryl (Sevin 4-oil). Bul. Environ. 

Contam. Toxicol. 17:379-386.

VI. Listing of Agencies and Persons Consulted 

Eric Hein, Endangered Species Biologist, F&WS-Ecological Services, 2105 Osuna Road NE, 

Albuquerque, NM 87113.

Patricia Zenone, Endangered Species Biologist, F&WS-Ecological Services, 2105 Osuna Road

NE, Albuquerque, NM 87113.

William Wesela, Program Manager, USDA-APHIS-PPQ, Unit 134, 4700 River Road,

Riverdale, MD 20737.

Kai Caraher, Biological Scientist, USDA- APHIS PPQ, Unit 150, 4700 River Road,

Riverdale, MD 20737.

Derek Woller PhD., Supervisory Entomologist, Science and Technology, USDA-APHIS-PPQ, 

3645 E. Wier Ave, Phoenix, Arizona 85040.

Jim Warren Ph.D., Environmental Protection Specialist/Environmental Toxicologist, USDA –

APHIS, PPD - Environmental and Risk Analysis Services, 1200 Cherry Brook Drive, Suite 

100, Little Rock, AR 72211
`

36

Appendix A - APHIS Rangeland Grasshopper and Mormon Cricket 

Suppression Program

FY-2020 Treatment Guidelines

Version 03/09/2020

The objectives of the APHIS Rangeland Grasshopper and Mormon Cricket Suppression Program 

are to 1) conduct surveys in the Western States; 2) provide technical assistance to land managers 

and private landowners; and 3) when funds permit, suppress economically damaging grasshopper 

and Mormon cricket outbreaks on Federal, Tribal, State, and/or private rangeland. The Plant 

Protection Act of 2000 provides APHIS the authority to take these actions.

General Guidelines for Grasshopper / Mormon Cricket Treatments

1. All treatments must be in accordance with:

a. the Plant Protection Act of 2000;

b. applicable environmental laws and policies such as: the National Environmental Policy 

Act, the Endangered Species Act, the Federal Insecticide, Fungicide, and Rodenticide Act, 

and the Clean Water Act (including National Pollutant Discharge Elimination System 

requirements – if applicable); 

c. applicable state laws; 

d. APHIS Directives pertaining to the proposed action;

e. Memoranda of Understanding with other Federal agencies.

2. Subject to the availability of funds, upon request of the administering agency, the agriculture 

department of an affected State, or private landowners, APHIS, to protect rangeland, shall 

immediately treat Federal, Tribal, State, or private lands that are infested with grasshoppers or 

Mormon crickets at levels of economic infestation, unless APHIS determines that delaying 

treatment will not cause greater economic damage to adjacent owners of rangeland. In carrying 

out this section, APHIS shall work in conjunction with other Federal, State, Tribal, and private 

prevention, control, or suppression efforts to protect rangeland.

3. Prior to the treatment season, conduct meetings or provide guidance that allows for public 

participation in the decision making process. In addition, notify Federal, State and Tribal land 

managers and private landowners of the potential for grasshopper and Mormon cricket outbreaks 

on their lands. Request that the land manager / land owner advise APHIS of any sensitive sites 

that may exist in the proposed treatment areas.

4. Consultation with local Tribal representatives will take place prior to treatment programs to fully 

inform the Tribes of possible actions APHIS may take on Tribal lands.

5. On APHIS run suppression programs, the Federal government will bear the cost of treatment up 

to 100 percent on Federal and Tribal Trust land, 50 percent of the cost on State land, and 33 

percent of cost on private land. There is an additional 16.15% charge, however, on any funds 

received by APHIS for federal involvement with suppression treatments. 
37

6. Land managers are responsible for the overall management of rangeland under their control to 

prevent or reduce the severity of grasshopper and Mormon cricket outbreaks. Land managers are 

encouraged to have implemented Integrated Pest Management Systems prior to requesting a 

treatment. In the absence of available funding or in the place of APHIS funding, the Federal land 

management agency, Tribal authority or other party/ies may opt to reimburse APHIS for 

suppression treatments. Interagency agreements or reimbursement agreements must be completed 

prior to the start of treatments which will be charged thereto.

7. There are situations where APHIS may be requested to treat rangeland that also includes small 

areas where crops are being grown (typically less than 10 percent of the treatment area). In those 

situations, the crop owner pays the entire treatment costs on the croplands. 

NOTE: The insecticide being considered must be labeled for the included crop as well as 

rangeland and current Worker Protection Standards must be followed by the applicator and 

private landowner.

8. In some cases, rangeland treatments may be conducted by other federal agencies (e.g., Forest 

Service, Bureau of Land Management, or Bureau of Indian Affairs) or by non-federal entities 

(e.g., Grazing Association or County Pest District). APHIS may choose to assist these groups in a 

variety of ways, such as:

a. loaning equipment (an agreement may be required):

b. contributing in-kind services such as surveys to determine insect species, instars, and 

infestation levels;

c. monitoring for effectiveness of the treatment;

d. providing technical guidance.

9. In areas considered for treatment, State-registered beekeepers and organic producers shall be 

notified in advance of proposed treatments. If necessary, non-treated buffer zones can be 

established. 

Operational Procedures 

GENERAL PROCEDURES FOR ALL AERIAL AND GROUND APPLICATIONS

1. Follow all applicable Federal, Tribal, State and local laws and regulations in conducting 

grasshopper and Mormon cricket suppression treatments.

2. Notify residents within treatment areas, or their designated representatives, prior to proposed 

operations. Advise them of the control method to be used, proposed method of application, and 

precautions to be taken.

3. One of the following insecticides that are labeled for rangeland use can be used for a suppression 

treatment of grasshoppers and Mormon crickets: 

A. Carbaryl

a. solid bait

b. ultra-low volume (ULV) spray

B. Diflubenzuron ULV spray
38

C. Malathion ULV spray

D. Chlorantraniliprole

 

4. Do not apply insecticides directly to water bodies (defined herein as reservoirs, lakes, ponds, 

pools left by seasonal streams, springs, wetlands, and perennial streams and rivers). 

Furthermore, provide the following buffers for water bodies: 

• 500-foot buffer with aerial liquid insecticide.

• 200 foot buffer with ground liquid insecticide.

• 200-foot buffer with aerial bait.

• 50-foot buffer with ground bait.

 

5. Instruct program personnel in the safe use of equipment, materials and procedures; supervise to 

ensure safety procedures are properly followed.

6. Conduct mixing, loading, and unloading in an approved area where an accidental spill would not 

contaminate a water body.

7. Each aerial suppression program will have a Contracting Officer’s Representative (COR) OR a 

Treatment Manager on site. Each State will have at least one COR available to assist the 

Contracting Officer (CO) in GH/MC aerial suppression programs. 

NOTE: A Treatment Manager is an individual that the COR has delegated authority to oversee the 

actual suppression treatment; someone who is on the treatment site and overseeing / coordinating 

the treatment and communicating with the COR. No specific training is required, but knowledge 

of the Aerial Application Manual and treatment experience is critical; attendance to the Aerial 

Applicators Workshop is very beneficial. 

8. Each suppression program will conduct environmental monitoring as outlined in the current 

year’s Environmental Monitoring Plan.

APHIS will assess and monitor rangeland treatments for the efficacy of the treatment, to verify 

that a suppression treatment program has properly been implemented, and to assure that any 

environmentally sensitive sites are protected. 

9. APHIS reporting requirements associated with grasshopper / Mormon cricket suppression 

treatments can be found in the APHIS Grasshopper Program Guidebook: 

http://www.aphis.usda.gov/import_export/plants/manuals/domestic/downloads/grasshopper.pdf

SPECIFIC PROCEDURES FOR AERIAL APPLICATIONS 

1. APHIS Aerial treatment contracts will adhere to the current year’s Statement of Work (SOW).
39

2. Minimize the potential for drift and volatilization by not using ULV sprays when the following 

conditions exist in the spray area:

a. Wind velocity exceeds 10 miles per hour (unless state law requires lower wind speed);

b. Rain is falling or is imminent;

c. Dew is present over large areas within the treatment block;

d. There is air turbulence that could affect the spray deposition;

e. Temperature inversions (ground temperature higher than air temperature) develop and 

deposition onto the ground is affected.

3. Weather conditions will be monitored and documented during application and treatment will be 

suspended when conditions could jeopardize the correct spray placement or pilot safety.

4. Application aircraft will fly at a median altitude of 1 to 1.5 times the wingspan of the aircraft 

whenever possible or as specified by the COR or the Treatment Manager.

5. Whenever possible, plan aerial ferrying and turnaround routes to avoid flights over congested 

areas, water bodies, and other sensitive areas that are not to be treated. 

Appendix B: Chemical Safety & Emergency Spill Plan Information & 

Equipment

All individuals applying chemicals will receive adequate training on safety and application 

procedures prior to any treatment. This refers to APHIS, NMDA and contracted aerial applicator

personnel (include in the prospectus) and is included in the 2009 Guidelines for Treatment of 

Rangeland Suppression of Grasshoppers and Mormon Crickets.

A copy of the labels and material safety data sheets (MSDS) for the chemicals will be

available at all times during the rangeland suppression operations. Employees will be

completely familiar with the information in these documents in case it is needed in the

event of a spill or incident.

Required personal protective equipment (PPE) for applicators and handlers must be worn at all

times when chemicals are being mixed, applied and equipment cleaned.

An emergency spill kit, with direction for use, will be present on site before the arrival of

chemicals and throughout the application process. Employees will be trained in the use of the 

spill kit prior to initiation of operations.

Procedures for Chemical Spill Containment

Based on information contended in the EPA document “Applying Pesticides Correctly: A

Guide for Private and Commercial Applicators” and rules and regulations of the New Mexico 

Department of Agriculture’s Pesticide Management Bureau.

The following information will be reviewed by all workers who handle chemicals.

Immediately notify the direct supervisor of an incident or spill. Identify the nature of the

incident and extent of the spill, including the product and chemical name and the EPA

registration number.
40

Remove any injured or contaminated person to a safe area. Remove contaminated clothing and

follow MSDS guidelines for emergency first-aid procedures regarding exposure. Do not leave 

an injured person alone. Obtain medical help for any injured person.

Contain the spread of the spilled chemical as much as possible at the site. Prevent the spilled 

chemical from run-off or fire. Cover the spill with absorbent material. If the spill is greater than

2 gallons of chemical, notify the local hazmat unit or fire department and follow their

instructions for further remedial actions. Restrict entry to the spill area. Follow disposal of 

contaminated materials according to label instructions and state requirements.

1. Procedures for Chemical Handling: Mixing, Loading and Disposal

Mixing of the chemical and adjuvants will be done at least 100 feet from any well head or

surface water.

Dilution water will be added to the spray container prior to the addition of the chemical

concentrate.

Hoses used to add dilution water to the spray container shall be equipped with a device to

prevent back–siphoning or a minimum 2-inch gap.

Workers mixing chemicals will wear the maximum personal protective equipment required on 

the label.

Empty containers will be triple rinsed. All rinsate will be added to the spray mix container or

tank or disposed of on the application site at a rate that does not exceed amounts stated on the 

label.

Unused chemical will be stored and secured in a protected area with appropriate advisory

signage.

Empty and rinsed non-refillable chemical containers will be punctured and disposed of

according to the label’s specified instructions.

For additional information please contact the New Mexico State Plant Health Director, Waleska 

Ramirez at: 575/527-6985, or the Western Region Grasshopper/Mormon Cricket Program 

Manager, Melinda Sullivan at: 970/494-7580.
41

Appendix C: Map of the Affected Environment
42
43
44

Appendix D: FWS/NMFS Correspondence

1) 2005 Lincoln County B.A; FWS Consultation # 2-22-05-I-0460

2) 2006 New Mexico B.A; FWS Consultation # 22420-2006-I-0069

3) 2007 New Mexico B.A, FWS Consultation #22420-2006-I-0069a

4) 2008 New Mexico B.A, FWS Consultation #22420-2008-I-0062

5) 2009 New Mexico B.A, FWS Consultation #22420-2009-TA-0027

6) 2010 – 2015 New Mexico B.A, FWS Consultation #22420-2010-I-0047

7) 2015 – 2020 New Mexico B.A. FWS Consultation - #02ENNM00-2015-I-0244 (see below)
45

March 30, 2015

Consultation # 02ENNM00-2015-I-0244

Shawn Carson, PPQ 

Officer 270 South 17th 

Street

Las Cruces, New Mexico 88005 

Dear Mr. Carson:

Thank you for the March 19, 2015, Biological Assessment (BA) for your proposed 

Rangeland Grasshopper and Mormon Cricket Suppression Program in New Mexico 

(Suppression Program). The USDA Animal Plant Health Inspection Service (APHIS) 

proposes to conduct the Suppression Program in New Mexico from 2015 to 2020. Our 

understanding is that APHIS will develop site-specific environmental assessments as needed 

that analyze the impacts of the Suppression Program. All rangeland treatments, and most crop 

protection programs, will be applied utilizing the reduced area agent treatments (RAAT’s) 

techniques. These treatments differ from traditional programs by applying less suppressive 

agent to fewer acres while maintaining efficacy. This information is detailed in the biological 

assessment, which is hereby incorporated by reference (APHIS 2015). Additionally, you have 

proposed a variety of species- specific protective measures (e.g., buffers around locations) to 

reduce potential effects to be insignificant and discountable.

You requested and we concur that the proposed action “may affect, is not likely to adversely 

affect” the following species and critical habitats where applicable: lesser long-nosed bat 

(Leptonycteris curasocea yerbabuenae), Mexican spotted owl (Strix occidentalis lucida) and 

United States Department of the Interior

FISH AND WILDLIFE SERVICE

New Mexico Ecological Services Field Office 

2105 Osuna Road NE

Albuquerque, New Mexico 87113 

Telephone 505-346-2525 Fax 505-346-2542

www.fws.gov/southwest/es/newmexico/
46

its critical habitat, Yellow-billed cuckoo (Coccyzus americanus) and its proposed critical 

habitat, southwestern willow fly-catcher (Empidonax traillii extimus) and its critical habitat, 

northern aplomado falcon (Falco femoralis septentrionalis), Rio Grande silvery minnow 

(Hybognathus amarus) and its critical habitat, Gila trout (Oncorhynchus gilae), Gila chub 

(Gila intermedia) and its critical habitat, Chihuahua chub (Gila nigrescens), Loach minnow 

(Tiroga cobitis) and its critical habitat, Gila topminnow (Poeciliopsis occidentalis), spikedace 

(Meda fulgida) and its critical habitat, Zuni bluehead Sucker (Catostomus discobolus yarrowi) 

and its proposed critical habitat, Jemez Mountains salamander (Plethodon neomexicanus) and 

its critical habitat, Northern Mexican gartersnake (Thamnophis eques megalops) and its 

proposed critical habitat, Narrow- headed gartersnake and its proposed critical habitat 

(Thamnophis rufipunctatus), lesser prairie- chicken (Tympanuchus pallidicinctus), New 

Mexico meadow jumping mouse (Zapus hudsonius luteus) and its proposed critical habitat, 

Mesa Verde cactus (Sclerocactus mesae-verdae), Knowlton’s cactus (Pediocactus knowltonii), 

Mancos milk-vetch (Astragalus humillimus), Pecos sunflower (Helianthus paradoxus) and its 

critical habitat, Gypsum wild-buckwheat (Eriogonum gypsophilum) and its critical habitat, and 

the Sacramento prickly poppy (Argemone pleiacantha spp. pinnatisecta). You proposed a 

variety of protective measures (e.g., buffers around species locations) to reduce potential 

effects to be insignificant and discountable.

This concludes section 7 consultation regarding the proposed action. If monitoring or other 

information results in modification or the inability to complete all aspects of the proposed 

action, consultation should be reinitiated. Please contact the Service if: 1) future surveys 

detect listed, proposed or candidate species in habitats where they have not been previously 

observed; 2) the proposed action changes or new information reveals effects of the proposal to 

listed species that have not been considered in this analysis; or 3) a new species is listed or 

critical habitat designated that may be affected by the action.

Thank you for your concern for endangered species and New Mexico’s wildlife habitats. If 

you have any questions, please contact Eric Hein of my staff at the letterhead address or at 

(505) 761- 4735.

Sincerely,

Digitally signed by ERIC HEIN DN: c=US, o=U.S.Government,

ou=Department of the Interior, ou=U.S. Fish and Wildlife Service, cn=ERIC HEIN, 0.9.2342.19200300.100.1.1=1400100058

9983

Date: 2015.03.30 11:56:54 -06'00'

Wally Murphy Field Supervisor

cc:

Director, New Mexico Department of Game and Fish, Santa Fe, New Mexico

Director, New Mexico Energy, Minerals, and Natural Resources Department, Forestry 

Division, Santa Fe, New Mexico

ERIC HEIN
47

Appendix E: State and Tribal Species of Concern Review:

1) Navajo Nation, Division of Natural Resources: Endangered Species List (Resource 

Committee Resolution No. RCS-41-08), September 10, 2008. 

https://www.nndfw.org/nnhp/nnhp_nesl.pdf

2) New Mexico Energy, Minerals & Natural Resources Department, Forestry and Resource 

Conservation Division, Title 19, Chapter 21 Part 2.9 Endangered Plants Species List.

August 31, 1995.

3) New Mexico Department of Game and Fish: Conservation Services Division;

Threatened and Endangered Fishes of New Mexico by David L. Propst, 1999.

4) New Mexico Department of Game and Fish: Conservation Services Division: New Mexico 

Species of Concern – Status and Distribution. April 2003 

http://www.wildlife.state.nm.us/conservation/

5) New Mexico Rare Plant Technical Council: New Mexico Rare Plants; home page,

http://nmrareplants.unm.edu (last update: 09-04-2009)

Disturbance or Take of Golden/ Bald Eagles; effective 11-10-2009. 

http://www.fws.gov/migratorybirds/baldeagle.htm 

Appendix F: Potential Experimental Treatments:

APHIS-PPQ continues to refine its methods of grasshopper and Mormon cricket management in 

order to improve the Rangeland Grasshopper and Mormon Cricket Suppression Program’s 

abilities, make it more economically feasible, and environmentally acceptable. These 

refinements can include reduced rates of currently used pesticides, improved formulations, 

development of more target-specific baits, development of biological pesticide suppression 

alternatives, and improvements to aerial (e.g., incorporating the use of Unmanned Aircraft 

Systems (UAS)) and ground application equipment. A division of APHIS-PPQ-Science and 

Technology (S&T), the Center for Plant Health Science and Technology’s (CPHST) Phoenix 

Lab is located in Phoenix, AZ and its Rangeland Grasshopper and Mormon Cricket Management 

Team (AKA Rangeland Unit) conducts methods development and evaluations on behalf of the 

program. The Rangeland Unit’s primary mission is to comply with Section 7717 of the Plant 

Protection Act by testing and developing better, cheaper, and greener methods of managing 

grasshoppers and Mormon crickets on federal, state, tribal, and private rangelands (wildlife 

habitats and where domestic livestock graze) in the 17 contiguous western states of the U.S.A. 

To achieve this mission, experimental plots (often replicated and ranging in size from 14” or less 

to 10 acres to 40 acres to 160 acres to 640 acres) incorporating wild populations of grasshoppers 

(130 rangeland species are potential candidates, but, usually, only 8-12 are the specific targets) 

or Mormon crickets (Anabrus simplex) are used. The primary purpose of these plots is to test and 

refine equipment and methods, and develop formulations (of both insecticides and biopesticides 

in both liquid and bait form) that will possibly be used in future rangeland grasshopper and 

Mormon cricket program years. These investigations often occur in the summer (May-August) 
48

and the location(s) typically varies annually throughout the 17 states. Also included are “no 

treatment” (or control) areas that are monitored to determine the effect of no treatments. Some of 

these plots may be monitored for additional years to gather information on the effects of utilized 

insecticides on non-target arthropods. 

Examples of studies to test and refine equipment and methods using experimental plots may 

include using planes and ATVs to apply labeled materials using RAATs (Reduced Agent Area 

Treatments) methodology and blanket applications to determine expected mortalities associated 

with barrier or crop protection, and hot spot treatments. The use of a ULV (Ultra Low Volume) 

sprayer system (currently an Ulvamast by Micron Group) for applying biopesticides (such as 

native fungal pathogens) may also be an option. Another common application method for micro 

plots (that are often 14” across or less and are covered in varying cage types, preferred for 

treatments involving newly acquired insecticides/biopesticides) is simulating aerial applications 

via the FAASSTT (Field Aerial Application Spray Simulation Tower Technique). Furthermore, 

research is ongoing into the potential use of UAS for a number of purposes related to 

grasshopper and Mormon cricket surveillance and treatment. Field trials incorporating UAS 

would be operated by FAA-licensed pilots. 

Examples of studies to develop formulations using experimental plots may include 

RAATs/blanket applications of insecticides (in both liquid and bait forms) at standard or 

experimental doses, often for the sake of comparison effects. Biopesticide testing (often in the 

form of native fungal pathogens) are also of great interest and actively being developed. Also, 

stressor tests (mixtures of native pathogens combined with low doses of insecticides) may be 

conducted to determine if combinations enhance mortality. Further examples could include 

attractant/repellant studies. 

Insecticides likely to be involved in studies currently include: diflubenzuron (Dimilin and 

generics) and chlorantraniliprole (Prevathon). The standard diflubenzuron dose is 1.0 fl. oz. in a 

total volume of 31 fl. oz. while the standard chlorantraniliprole doses are 2 fl. oz. (RAATs) or 4 

fl. oz. (blanket), both in a total volume of 32 fl. oz. Biopesticides (all U.S. natives and fungal 

pathogens) likely to be involved in studies currently include: Metarhizium anisopliae isolate 

DWR2009 and Beauveria bassiana. 

Studies and experimental plots are typically located on located on large acreages of rangelands 

and the Rangeland Unit often works on private land with the permission of landowners. 

Locations of experimental trials will be made available to the appropriate agencies in order to 

ensure these activities are not conducted near sensitive species or habitats. Due to the small size 

of the possible experimental micro plots, no adverse effects to the environment, including 

endangered species and sensitive habitats, are expected, and great care will be taken to 

investigate potential creatures and areas of particular concern things prior to setting up any 

studies.
49

Chlorantraniliprole Environmental Risk Analysis

Chlorantraniliprole

Chlorantraniliprole (RyanaxypyrTM) is a recently introduced insecticide that belongs to the 

anthranilic diamide insecticide class. The mode of action is the activation of insect ryanodine 

receptors which causes an uncontrolled release of calcium from smooth and striated muscles that 

impairs muscle regulation and causes paralysis in insects (EPA, 2008; Health Canada, 2008). 

Although these receptors occur in mammals, the insecticide is very selective to insect ryanodine 

receptors with more than 350-fold differential selectivity compared to mammalian receptors 

(Lahm et al., 2007; EPA, 2008). Primary activity of chlorantraniliprole is through ingestion 

with some contact toxicity against lepidopteran pests but also against Orthoptera, Coleoptera, 

Diptera, and Hemiptera pests (Hannig et al., 2009). The formulation proposed in the 

Grasshopper and Mormon Cricket Suppression Program (Program) is Prevathon® that can be 

applied by air or ground at a maximum rate of 20 fluid ounces per acre (fl oz/ac). The proposed 

treatment rates for this study are full coverage at 4 fl oz/ac and 2 fl oz/ac using RAAT on 

approximately 1920 acres per treatment. 

Human Health

Chlorantraniliprole is considered practically nontoxic via oral, dermal, and inhalation exposures 

(DuPont, 2010; EPA, 2008). Median lethality values (LD50) from oral and dermal exposure to 

the active ingredient, chlorantraniliprole, and the proposed formulation exceed the highest test 

concentration tested (5,000 milligrams/kilogram (mg/kg)). Inhalation toxicity is also very low 

for the technical material and the formulation with median lethality values exceeding the highest 

test concentration (2.1 mg/L). Available acute toxicity data suggests that the acute toxicity 

between the active ingredient and the formulation are comparable. Prevathon® is not 

considered an irritant to the eyes or skin, and is not a skin sensitizer. In addition 

chlorantraniliprole is not considered to be carcinogenic or mutagenic, and is not known to cause 

reproductive or developmental toxicity. The no observable effect level (NOEL) in reproductive 

and developmental toxicity studies was 1,000 mg/kg/day, or the highest concentration tested 

(EPA, 2008). Studies designed to assess neurotoxicity and effects on the immune system show 

no effects at a range of doses from the low mg/kg range to greater than 1,000 mg/kg. 

Exposure and risk to all population groups is expected to be negligible. The potential for 

exposure is greatest for workers from handling and applying Prevathon®, however the very low 

toxicity and label required personal protective equipment result in minimal exposure and risk to 

this subgroup of the population. Exposure and risk to the general public will also be negligible 

based on Program use of Prevathon®. Applications will be made to rangeland over an area of 

approximately 1920 acres for each treatment rate. These areas are part of a proposed three year 

study and no crop would be harvested for human consumption and any use for grazing would 

follow label requirements. Therefore significant dietary human exposure from consuming food 

containing residues of chlorantraniliprole would not occur. Conservative estimates of potential 

groundwater contamination using standard USEPA models suggest residues would be orders of 

magnitude below any levels of concern for the general public, including children. Drift may 

occur during applications however Program restrictions regarding treatment proximity to 

schools, and other measures to reduce drift, will minimize the potential for exposure and risk to 

the general public (USDA, 2013). 
50

Ecological Resources

Toxicity to most non-target organisms is low based on available toxicity data. Acute fish 

toxicity is low with median lethality values (LC50) for freshwater and marine test species above 

the highest test concentration tested. Amphibian toxicity data does not appear to be available 

however based on the reported toxicity values for fish the toxicity to amphibians is expected to 

be low. Aquatic invertebrates are more sensitive to the effects of chlorantraniliprole with median 

lethality and effect concentrations ranging from 0.0098 milligrams per liter (mg/L) for the 

freshwater cladoceran, Daphnia magna, to 1.15 mg/L for marine mysid shrimp (Barbee et al., 

2010; EPA, 2012). Chronic no observable effect concentrations (NOEC) range from 0.0045 

mg/L for D. magna to 0.695 mg/L for a marine mysid (EPA, 2012). Available aquatic plant 

toxicity data suggests low toxicity of chlorantraniliprole to diatoms, algae, and aquatic 

macrophytes with median effect concentrations exceeding the highest test concentration (EPA, 

2008). Primary and secondary metabolites that could occur in aquatic environments are less 

toxic than the parent material when comparing toxicity values for the freshwater cladoceran, D. 

magna (EPA, 2012).

The exposure and risk to aquatic organisms from the proposed applications of Prevathon® will be 

negligible based on the low toxicity of chlorantraniliprole, and program restrictions regarding 

applications near surface water. The Program currently uses a 200 foot ground and 500 foot 

aerial application buffer from surface water. Using standardized drift modeling at the highest 

application rate proposed in this study results in shallow water residues of chlorantraniliprole 

that are approximately ten fold below the most sensitive sublethal endpoint for aquatic 

invertebrates (USDA, 2014). Residue values were also approximately ten fold below the most 

sensitive acute toxicity value for aquatic vertebrates and four orders of magnitude below the 

acute toxicity values for fish. No indirect effects would be expected for aquatic vertebrates that 

depend on aquatic plants and invertebrates for habitat and prey from the proposed use of 

Prevathon®.

Acute toxicity for terrestrial wildlife such as mammals and birds is very low with median 

lethality values exceeding the highest test concentration for mammals and birds, such as 

bobwhite quail and the mallard (EPA, 2012). Laboratory toxicity data for technical and 

formulated chlorantraniliprole shows that the product is practically non-toxic to honey bees in 

oral or contact exposures. In semi-field studies using two formulations reported NOECs ranging 

from 52.5 to 156.16 g a.i.chlorantraniliprole/ha (Dinter et al., 2009; EPA, 2008). Three semifield honey bee tunnel tests demonstrated no behavioral or flight intensity effects nor were any 

hive related impacts noted at a dose of 52.5 g/ha (Dinter et al., 2009). The lowest reported 

NOEC is approximately four times the proposed RAATs application rate for chlorantraniliprole 

and two times the proposed full rate. Similar NOECs have been observed for other invertebrates 

such as the hover fly, Episyrphus balteatus, ladybird beetle larvae, Coccinella septempunctata, 

green lacewing, Chrysoperla carnea, the plant bug, Typhlodromus pyri, and predatory mite, 

Orius laevigatus (EPA, 2008; EPA, 2012). The low toxicity to non-target terrestrial 

invertebrates has also been observed in greenhouse and field applications. Gradish et al. (2011) 

reported low acute toxicity of formulated chlorantraniliprole to the parasitoid, Eretmocerus 

eremicus, the pirate bug, Orius insidiosus and the predatory mite, Amblyseius swirskii, in 48-

hour exposures. Brugger et al. (2010) evaluated lethal and sublethal impacts of formulated 

chlorantraniliprole to seven parasitic hymenopterans and found no negative impacts on adult 

survival, percentage parasitism, or emergence when compared to controls at rates well above the 
51

full and RAATs program rates. The lack of toxicity in other insect groups at rates that are toxic 

to grasshoppers is related to the activity of chlorantraniliprole which is primarily through 

ingestion. Insects such as grasshoppers and larval Coleoptera and Lepidoptera would receive a 

larger dose consuming treated plant material compared to many of the non-target pests that have 

been evaluated in the literature. The impacts to this group of non-target invertebrates, as well as 

others, will be evaluated in the proposed three year study.

Exposure and risk to terrestrial vertebrates that may consume treated plant material or insects in 

the proposed spray blocks will be negligible. USEPA exposure models to this group of nontarget organisms from treated plant material and insects at maximum Prevathon® rates show that 

residues are at least two orders of magnitude below the most sensitive toxicity endpoint for wild 

mammals or birds (USDA, 2014). Indirect risk to this group of organisms is also not anticipated 

based on the selectivity of chlorantraniliprole to certain insect taxa and the relatively small areas 

of treatment. Treatment blocks will be approximately 1920 acres at the 2 and 4 fl. oz/ac rate 

which would be smaller than the potential foraging range for many mammals and birds that are 

insectivores. Additionally the selective nature of chlorantraniliprole to certain insect taxa and the 

low application rates suggest that impacts to all terrestrial invertebrates would not be anticipated. 

Any decrease in chlorantraniliprole-sensitive terrestrial invertebrate numbers would be expected 

to be local in nature due to the size of the treatment plots and recovery would occur more rapidly 

than in larger treatment areas due to immigration and the selective nature of chlorantraniliprole 

to certain life stages of invertebrates. There is some uncertainty in this assumption however the 

intent of the proposed study is to quantify the potential non-target impacts from the proposed 

applications. 

Environmental Quality

The potential for impacts to soil, air and water quality are expected to be negligible based on the 

proposed use pattern and available environmental fate data for chlorantraniliprole. Air quality is 

not expected to be significantly impacted since chlorantraniliprole has chemical properties that 

demonstrate it is not likely to volatilize into the atmosphere (EPA, 2008). There will be some 

insecticide present in the atmosphere within and adjacent to the spray block immediately after 

application as drift but this will be localized and of short duration. Chlorantraniliprole has low 

solubility in water (<1 mg/L) and is susceptible to sunlight with a half-life of 0.31 days. 

Microbial degradation in water and pH-related effects to chlorantraniliprole are minor with halflives greater than 125 days (EPA, 2008). Slow degradation in soil is also anticipated with halflives ranging from 228 to 924 days in various soil types (EPA, 2008). Chlorantraniliprole has a 

varying affinity for binding to soil, but is generally low, suggesting that it may be susceptible to 

run-off during storm events. However the proposed use rates and program restrictions regarding 

buffers suggest that surface and ground water quality will not be impacted from the proposed 

Program use of chlorantraniliprole. 

Summary 

Chlorantraniliprole use in the proposed study will have negligible risk to human health. Risk to 

workers will be greatest due to a greater chance of exposure however the risk is very low based 

on favorable toxicity data and the use of personal protective equipment. Risk to the general 

population is not expected based on available toxicity data and the lack of significant exposure 

from the proposed study. Risk to most non-target fish and wildlife is also expected to be 

negligible based on the very low toxicity to most non-target organisms and low probability of 
52

exposure due to the proposed study design and Program restrictions to protect water quality. 

There is some risk to certain life stages of terrestrial insect taxa that may be sensitive to 

chlorantraniliprole but these impacts are expected to be localized within the treatment blocks and 

will be quantified in the proposed study. 

References 

Barbee, G.C., McClain, W.R., Lanka, S.K. and M.J. Stout. 2010. Acute toxicity of 

chlorantraniliprole to non-target crayfish (Procambarus clarkii) associated with rice–crayfish 

cropping systems. Pest Manag. Sci. 66: 996–1001.

Brugger, K.E., Cole, P.G., Newman, I.C., Parker, P., Scholz, B., Suvagia, P., Walker, G. and 

T.G. Hammond. 2010. Selectivity of chlorantraniliprole to parasitoid wasps. Pest Manag. Sci. 

66: 1075–1081. 

Dinter, A., Brugger, K.E., Frost, N.M. and M.D. Woodward. 2009. Chlorantraniliprole 

(Rynaxypyr): A novel DuPontTM insecticide with low toxicity and low risk for honey bees (Apis 

mellifera) and bumble bees (Bombus terrestris) providing excellent tools for uses in integrated 

pest management. Hazards of pesticides to bees – 10th International Symposium of the ICP-Bee 

Protection Group. Pp. 84-96.

Dupont. 2010. Material Safety Data Sheet - Prevathon®.

Gradish, A.E., Scott-Dupree, C.D., Shipp, L. and R. Harris. 2011. Effect of reduced risk 

pesticides on greenhouse vegetable arthropod biological control agents. Pest Manag. Sci. 67: 

82–86.

Hannig, G.T., Ziegler, M. and P.G. Marcon. 2009. Feeding cessation effects of 

chlorantraniliprole, new anthranilic diamide insecticide, in comparison with several insecticides 

in distinct chemical classes and mode-of-action groups. Pest Manag. Sci. 65: 969–974.

Health Canada, 2008. Evaluation report: Chlorantraniliprole.

Lahm, G.P., Stevenson, T.M., Selby, T. P., Freudenberger, J.H., Cordova, D., Flexner, L., Bellin, 

C.A., Dubas, C.M., Smith, B.K., Hughes, K.A., Hollinghaus, J.G., Clark, C.E. and Benner, E.A., 

2007. Rynaxypyr®: A new insecticidal anthranilic diamide that acts as a potent and selective 

ryanodine receptor activator. Bioorganic & Med. Chem. Letters 17:6274–6279.

U.S. Department of Agriculture, Animal and Plant Health Inspection Service, 2013. Rangeland 

grasshopper/Mormon cricket suppression program aerial application: statement of work. 41 pp.

U.S. Department of Agriculture, Animal and Plant Health Inspection Service, 2014. Draft 

Biological Assessment for the APHIS Rangeland Grasshopper and Mormon Cricket Suppression 

Program. 168 pp.

U.S. Environmental Protection Agency, 2008. Pesticide fact sheet: Chlorantraniliprole. Office 

of Prevention, Pesticides and Toxic Substances. 77 pp. 
53

U.S. Environmental Protection Agency, 2012. Ecotox database accessed at: 

http://cfpub.epa.gov/ecotox/

Appendix G: APHIS response to public comments on the New Mexico draft 

EA (EA Number: NM-20-01)

 

USDA APHIS received two public responses to the publication of the Draft 

EA. Public comments were received from the Xerces Society and the Center for Biological 

Diversity. Comments similar in nature were grouped under one response. Comments that were 

editorial in nature or requested additional citations are not addressed in the appendix but were 

incorporated into the final EA, where appropriate. The Grasshopper Program has decided not to 

use chlorantraniliprole in New Mexico during 2020, any exposure scenarios which the 

commenters are concerned about are not relevant, and all references to these two chemicals 

were removed from the final EA.

Comment 1 

USDA APHIS received one comment about the EAs providing little in the way of solid 

information about where, how, and when the treatments may actually occur within the counties 

covered under the EAs, during the year 2020, which makes it impossible to determine if effects 

would actually be significant or not. 

APHIS described the purpose and need for grasshopper suppression treatments, potential 

treatment options, the affected environment within the state, and an analysis of the potential 

environmental consequences in the Draft EAs that were made available for public comment. 

These documents become programmatic because APHIS cannot precisely predict where an 

outbreak will occur each year; we only know that outbreaks will occur, and treatments in a 

timely manner will be absolutely necessary. The emergency response aspect is why site-specific 

treatment details cannot be known, analyzed, and published in advance. APHIS relies on its 

emergency provisions within its NEPA Implementing regulations (7 CFR 372.10) to address 

these situations.

Please be aware that local agreements with Tribal Nations may preclude disclosure of Tribal 

information to the public or outside of APHIS without the consent of the Tribal Administrator. 

Individuals may request information on the specific treatment areas on Tribal Lands from the 

individual Tribal Nations.

Comment 2 

USDA APHIS received one comment concerning the lack of transparency about the location of 

actual treatment areas, particularly on public lands, being a disservice to the public that prevents 

the public from reviewing sufficient information to be able to gauge justification for and the risks 

involved in the suppression effort. 

APHIS did not withhold the location of actual treatment areas while preparing the Draft EA, but 

rather those facts were not known at that time because economically damaging grasshopper 

populations had not become apparent. See previous comment concerning the prevention of the 
54

commenter’s ability to gauge the justification and risks of treatments within the proposed action 

areas. 

Comment 3

APHIS received one comment urging APHIS to provide the public with maps of specific 

treatment areas and proposed treatment strategies (including proposed date of application and 

chemical and rate to be used), immediately after approving any treatment and at least 14 days 

prior to implementation of any treatment. This comment suggested that this specific information 

be posted at the APHIS website as soon as it is available, sent to interested parties, and made 

available for public comment.

In most circumstances, APHIS is not able to accurately predict specific treatment areas 

and treatment strategies months or even weeks before grasshopper populations reach economic 

infestation levels. The need for rapid and effective response when an outbreak occurs limits the 

options available to APHIS to inform the public other than those stakeholders who could be 

directly affected by the actual application. APHIS typically does not have 14 days between 

planning a treatment and the actual application because of the rapid population growth 

and potential damage of grasshopper infestations.

New Mexico does not anticipate any sponsored treatments in 2020. This EA was prepared in the 

event that if an outbreak were to occur and APHIS is requested to make a treatment, and 

approves the requested treatment, that they can be made in a timely manner RAATs is our 

preferred method of treatment if a treatment is required. We will only use a conventional 

treatment if one is required (extreme number of grasshoppers, specifically requested by the 

landowner(s)). Releasing EAs after treatment requests is not possible. There is a very small 

window in which to suppress grasshopper populations. APHIS prefers to use diflubenzuron 

which requires treatment at an early instar. If a treatment was to occur in New Mexico, 

treatment maps would be provided to the land managers (Rancher) and the general public would 

be notified using local available communications outlets.

Comment 4

APHIS received one comment that mentioned “APHIS’ procedure to approve or disapprove 

treatments based on a cost-benefit analysis performed using the “Hopper” model” and that is 

site-specific data are not available or current, APHIS must use protective values as defaults in 

Hopper.”

 

The “Hopper” model is an older model. However, we encourage our stakeholders to use 

“CARMA”. This is an updated model that has included New Mexico in the modeling.

In New Mexico, general site specific data, which is used to determine treatments in real time and 

gathered at time of actual surveys are used to make treatment decisions. The general site specific 

data include: grasshopper densities, species complex, dominant species, dominant life stage, 

grazing allotment terrain, soil types, range conditions, local weather patterns (wind, temp.,

precipitation),slope and aspect for hatching beds, animal unit months (AUM’s) present 

in grazing allotment, forage damage estimates, number of potential AUM’s consumed by 

grasshopper population, potential AUM’s managed for allotment and value of the AUM, 
55

estimated cost of replacement feed for livestock, rotational time frame for grazing allotments, 

number of livestock in grazing allotment. These are all factors taken into consideration during 

the survey season. We rely on the landowner/land manager to make some of these decisions as 

they have a better understanding of alternative feed costs and availability, precipitation, their 

personal finances and their range productivity. We will assist in survey, ID and timing the 

treatment. Treatment determination is based on local factors including, but not limited to, land 

use, land manager objectives, crop and/or rangeland forage value, and pest density.

If treatment is requested on Tribal Lands, the individual site-specific data for determining 

treatment areas on Tribal Lands would be provided by the individual Tribal Nations. 

Comment 5

APHIS received one comment concerning how analysis of projected economic injury levels and 

ultimately, treatment decisions, might be determined in the absence of site-specific data 

(specifically rangeland productivity and composition, precipitation and soil moisture, 

accessibility and cost of alternative forage, effectiveness of treatment, cost of treatment, timing 

of treatment, and grasshopper population density, life stage, and species composition).

See comment 4 above. In New Mexico, general site specific data, which is used to determine 

treatments in real time and gathered at time of actual surveys are used to make treatment 

decisions.

Comment 6

APHIS received one comment related to disclosing its analysis for each of the seven variables 

mentioned in comment 5.

The site specific data that is used to determine treatments in real-time is gathered at the time of 

actual surveys. This data is not available at the time that the environmental assessments are 

prepared. See comment 4 for an example of general site specific data used to determine 

treatments.

The treatment areas and site-specific information from Tribal Lands will have to be provided by 

the individual Tribal Nations.

Comment 7

APHIS received one comment about providing the public with a more precise definition of when 

the threshold for spraying has been met.

Economic thresholds are variable based on the value of protected resources and management 

objectives. Baseline thresholds for Mormon crickets are 2 per sq. yd. and grasshoppers are 

8 per sq. yd., though neither of those thresholds guarantees justification for treatment alone. All 

of the site-specific data mentioned in comment 4 above are also considered for New Mexico.
56

Comment 8

APHIS received one comment urging APHIS to delay the publication of EA and FONSI until 

after treatment requests are received and all treatment areas have been delineated and are 

identified to the public.

APHIS has provide the public an opportunity to review and comment on the Draft EAs. 

Treatments can occur anywhere within the proposed action area in accordance with the 

published environmental protection measures (e.g. distance buffers from water resources) 

described in the EAs. The EAs provide sufficient detail to justify the risk analysis provided there 

in.

Comment 9

APHIS received one comment regarding the EAs list four insecticide options (diflubenzuron, 

carbaryl, malathion, and chlorantraniliprole), and states that the choice of which to use will be 

site-specific, without being clear about how that choice of insecticide is made.

The letters of request come from the individual land managers. The decision to use 

diflubenzuron is determined by the life stage of the dominant species within the 

outbreak population. In the case of early instars, diflubenzuron, the preferred insecticide, 

can produce 90 to 97% mortality. If the window for the use of diflubenzuron closes, as a result of 

treatment delays, then the only other option would be the use of Carbaryl 2% or 5% bait. There 

are certain species which are susceptible to carbaryl bait. If the species complex present in the 

outbreak is not susceptible to bait and the diflubenzuron window is closed, then no treatments 

will occur. This is discussed with the requesting land managers. Carbaryl XLR Plus (liquid 

formulation) is not being used in 2020.

The final EA has been updated to reflect the changes in the program.

Comment 10

APHIS received one comment concerning BeeREX calculating the expected environmental 

concentration (EEC) of diflubenzuron in pollen and nectar from foliar overspray as 1.76 mg/kg, 

which is equivalent to 1760 ppb.

Nectar and pollen values in BeeREX are based on residues that would be expected to occur from 

direct pesticide applications to long grass which is a food source EPA estimates in its T-REX 

model. These assumptions may overestimate expected residues of diflubenzuron in pollen and 

nectar. Available data for diflubenzuron pollen residues in crops show a low frequency of 

occurrence and low concentrations. The concentration in pollen will depend on application 

rates and when applications are made relative to flower bloom. Program applications of 

diflubenzuron are at the lower end of labeled use rates for Dimilin due to the sensitivity of 

Orthoptera. In addition, the Program uses rates less than the current labeled rates for 

grasshoppers and other labeled crops and makes only one application.

Comment 11

APHIS received one comment regarding chitin synthesis and its importance in the early life 

stages of insects, as they molt and form a new exoskeleton in various growth stages. The specific 
57

concern was that aquatic guideline tests, (or terrestrial invertebrate acute tests), which typically 

run for 48 hours, may not capture a molting stage, and thus underrepresent acute toxicity. Single 

doses may cause mortality, if received at a vulnerable time, and consequently, conclusions from 

RQs based on acute toxicity studies for invertebrates may not fully represent actual risk.

APHIS agrees that chitin synthesis is a critical function for terrestrial and aquatic invertebrates.

APHIS in its risk assessments prepared for each Program insecticide summarized available 

acute and chronic toxicity data. This would include studies of short duration such as 48 to 96 

hours as well as much longer term studies that would evaluate continuous exposures during 

critical life stages and development.

Comment 12

APHIS received the following comment, “For honey bees (the surrogate species for risk 

assessment in the absence of other data), USEPA (2018) reported a chronic 21-day ED50 and 

NOAEL of 0.012 and <0.0064 μg a.i./larva, respectively. Utilizing these values 

in BeeREX (EPA’s model that calculates risk quotients for bees) and assuming an application 

rate of 0.016 lb. a.i./ac, BeeREX calculates an acute dietary risk quotient of 18.13 and a chronic 

dietary risk quotient of 33.99. (A threshold value is 1.0). Risk quotients this high above 1.0 

indicate a high concern for exposed bees.”

BeeREX is a tier one screening level model used by EPA to assess potential risk to pollinators. 

Estimates of risk quotients are used to determine if there is a presumption of risk that requires 

additional evaluation. APHIS also relies on available field data to further characterize the risks 

of Program insecticides to terrestrial and aquatic invertebrates, where available. A limitation 

of BeeREX is it does not account for pesticide degradation that would normally occur in 

Program treatments.

Nectar and pollen values in BeeREX are based on residues that would be expected to occur from 

direct pesticide applications to long grass which is a food source EPA estimates in its T-REX 

model. These assumptions may overestimate expected residues of diflubenzuron in pollen and 

nectar. Available data for diflubenzuron pollen residues in crops with higher use rates show a 

low frequency of occurrence and low concentrations. The concentration in pollen will depend 

on application rates and when applications are made relative to flower blooming.

Diflubenzuron Program applications are at the lower end of labeled use rates for Dimilin due to 

the sensitivity of Orthoptera. In addition, the Program uses rates less than the current labeled 

rates and makes one application.

Comment 13

APHIS received one comment, regarding the EIS disclosing that under some 

circumstances, Dimilin may be quite persistent; field dissipation studies in California citrus and 

Oregon apple orchards reported half-live values of 68.2 to 78 days. Rangeland persistence is 

unfortunately not available, but diflubenzuron applied to plants remains adsorbed to leaf surfaces 

for several weeks.

Diflubenzuron persistence varies depending on site conditions. Diflubenzuron degradation is 

microbially mediated with soil aerobic half-lives much less than dissipation half-lives. While 
58

dissipation half-lives may extend up to 78 days, they have also been shown to be much less under

other use patterns.

Comment 14

APHIS received the following comment, “APHIS discounted the pollinator risk by claiming that 

studies finding significant effects to pollinators utilized doses far above levels that would be used 

in grasshopper control. Unfortunately, this does not appear to be true for all studies 

cited. Mommaerts et al. (2006) conducted dose-response assays and found that exposure to 

diflubenzuron resulted in reproductive effects in Bombus terrestris, with only the doses at 0.001 

of maximum field recommended concentrations (MFRC) in pollen and 0.0001 in sugar water 

resulting in effects statistically similar to controls. The MFRC for diflubenzuron is listed in the 

study as 288 mg/L (equivalent to 288,000 ppb). At 1/10,000 of this level, diflubenzuron effects 

would be similar to controls only at levels at or below 28.8 ppb while at 1/1000 of this level, 

diflubenzuron “no effect” concentrations would be equivalent to 288 ppb. This analysis thus 

shows the opposite of what APHIS claims – that the effective dose for reproductive effects is 

actually far below the EEC expected for diflubenzuron at RAATS rates used in grasshopper 

suppression. This raises concern that the application of diflubenzuron at the specified RAATS 

rates may cause severe impacts to bee reproduction within treated areas.”

APHIS relied on available laboratory and field collected data for each Program insecticide to 

summarize risks to terrestrial invertebrates. In evaluating studies, APHIS also evaluated likely 

routes of exposure for Program treatments. Estimates of exposure using the EPA tier one 

screening model likely overestimate potential residues in pollen and nectar. 

Comment 15

APHIS received six comments about chlorantraniliprole.

Chlorantraniliprole is not proposed for use in 2020. The final EA has been updated to reflect the 

changes in the program.

Comment 16

APHIS received one comment concerning malathion being found to cause jeopardy in 1,284 

endangered species according to recent nationwide Biological Opinions

APHIS recognizes that EPA and the Services are continuing to develop updated national level 

consultations. APHIS currently consults with the Services at the State level for the Grasshopper 

program to ensure program activities do not adversely affect protected species or their critical 

habitat. 

Comment 17

APHIS received one comment regarding the EPA determined that carbaryl is likely to adversely 

affect 1,542 species.

The Endangered Species Act section 7 pesticide consultation process between the U.S. Fish and 

Wildlife Service and the National Marine Fisheries Service (the Services, collectively) and the 

EPA specifically concerns FIFRA pesticide registration and reregistration in the United States, 
59

including all registered uses of a pesticide. The state-level Biological Assessments for APHIS 

invasive species programs are separate from any consultations conducted in association with 

pesticide registration and reregistration process. 

The Agricultural Improvement Act of 2018 (Farm Bill) created a partnership between USDA, 

EPA, the Services, and the Council on Environmental Quality to improve the consultation 

process for pesticide registration and reregistration. USDA is committed to working to ensure 

consultations are conducted in a timely, transparent manner and based on the best available 

science. The Revised Method for National Level Listed Species Biological Evaluations of 

Conventional Pesticides provides a directionally improved path to ensuring that pesticides can 

continue to be used safely for agricultural production with minimal impacts to threatened and 

endangered species.

APHIS provided information about use of carbaryl to EPA for the FIFRA consultation for 

carbaryl. The Grasshopper Program use of carbaryl has in the past comprised substantially less 

than 1% of the percent crop treated (PCT) for rangeland use of carbaryl. This is the case for the 

reasonably foreseeable future. For rangeland, in the EPA BE, the Grasshopper Program’s very 

low usage was rounded up to <1% PCT, which gives an overestimate of rangeland acres treated 

and thus endangered species risk. APHIS use of carbaryl is even smaller compared to all uses of 

carbaryl. Further, the Grasshopper Program consults directly with the Services to ensure 

program activities do not adversely affect protected species or their critical habitat.

Comment 18

APHIS received the following comment, “The jeopardy and LAA calls for malathion and 

carbaryl should be included in the EAs and should preclude the use of these chemicals.”

APHIS consults directly with the U.S. Fish and Wildlife Service on treatments and methods. The 

U.S. Environmental Protection Agency’s on-going consultation on pesticide registration across 

all nationwide uses of program pesticides does not provide sufficiently detailed analysis or 

conclusions relevant to the Grasshopper Program.

Comment 19

APHIS received one comment that it should take into account the risk to native bees and 

butterflies from these treatments, especially those designated species of greatest conservation 

need. APHIS should constrain its treatments to take into account pollinator conservation needs, 

and improve its monitoring capability to try to understand what non-target effects actually occur 

as a result of the different treatments.

APHIS reduces the risk to native bees and pollinators through monitoring grasshopper and 

Mormon cricket populations and making pesticide applications in a manner that reduces the risk 

to this group of nontarget invertebrates. Monitoring grasshopper and Mormon cricket 

populations allows APHIS to determine if populations require treatment and to make treatments 

in a timely manner reducing pesticide use and emphasizing the use of Program insecticides that 

are not broad spectrum. Historical use of Program insecticides demonstrate that diflubenzuron 

is the preferred insecticide for use. Over 90% of the acreage treated by the Program has been 

with diflubenzuron. Diflubenzuron poses a reduced risk to native bees and pollinators compared 
60

to liquid carbaryl and malathion applications. In addition APHIS used RAATs to treat 

approximately 99% of the acres historically treated by the Program. APHIS also uses RAATs 

that are typically below the labeled RAAT rates further reducing the amount of insecticide used 

by the program. APHIS also emphasizes the use of carbaryl bait, where applicable, as a means 

to suppress pest populations while protecting native bees and pollinators. These methods of 

applications have been shown to be protective of nontarget invertebrates. These studies are 

referenced and summarized in the EIS.

Comment 20

APHIS received the following comment, This EA and the EIS claim that the use of untreated 

swaths will mitigate impacts to natural enemies, bees, and other wildlife. However, the width of 

the skipped swaths is not designated in advance in the EA, and there is no minimum width 

specified.

APHIS assumes that the reduced amount of pesticide that would occur using untreated swaths 

over a given treatment block will result in reduced risk to nontarget organisms by reducing 

exposure. The swath width can vary based on site specific conditions, however, the end result is 

reduced pesticide exposure over a treatment area. The EIS cites studies that demonstrate that the 

use of RAATs result in higher nontarget invertebrate populations compared to treatment blocks 

that did not use RAATs.

Comment 21

APHIS received two comments/recommendations about minimum swath widths, “Without 

knowing minimum (rather than maximum) swath widths that will be applied under this EA, it is 

hard to compare results from this study (Lockwood et al. 2000) to the results on non-targets 

expected under RAATS in this EA. 2). APHIS should commit to science-based methodologies to 

assess actual risk from the proposed treatments and institute minimum untreated swath widths 

wide enough to meaningfully minimize exposure to bees and other beneficials.”

The commenter references the work of Lockwood et al. 2000, this study 

looked at RAAT’s increasing swath widths in some instances by double skipping the untreated 

area. They also used ATV’s in their study which only have a minimum effect swath width of 30 

feet. Using UTV’s with the ability to adjust the hopper height, using the same ATV 

spreader, the minimum effective swath width can be increased to 40 feet, thus also increasing the 

untreated swath to 40 feet. APHIS uses science based methodologies to assess treatment 

related benefits or risks. APHIS has for decades funded the Science and Technology Research 

Lab in Phoenix, Arizona, which is specific to Rangeland Grasshopper and Mormon Cricket 

Program research and development. It is the only one of its kind in the U.S. The S&T Lab in 

cooperation with ASU researchers have evaluated nontarget invertebrate impacts in the past and 

have made recommendations to the Program.

Comment 22

APHIS received the following comment, “Although the EIS included a quantitative analysis of 

drift anticipated from ULV aerial applications to estimate deposition into aquatic areas, an 

analysis is not presented or available to back up the assumption that untreated areas (skipped 

swath widths) will act as refugia for natural enemies, bees, and other wildlife.”
61

The EIS cites studies that demonstrate that the use of RAATs result in higher nontarget 

invertebrate populations compared to treatment blocks that did not use RAATs.

Comment 23

APHIS received three comments about the drift analysis described in the EA, 1) “The drift 

analysis described in the EA assumed a droplet spectra size of fine to very fine (median diameter 

= 137.5 μm). However, labels do not require a minimum droplet size for ULV applications over 

rangeland, and other uses of ULV technology for pest control assume much smaller droplet 

sizes. EPA’s (2018) Ecological Risk Assessment for diflubenzuron uses AgDrift to estimate the 

drift fraction from aerial LV applications, although it is unclear whether AgDrift is validated for 

the purposes of predicting deposition of insecticides applied using ULV technology. EPA 

assumed a volume mean diameter (VMD) of 90 μm [note that this is approximately 2/3 of the 

VMD used in the APHIS analysis]. Under EPA’s analysis, the drift fraction comprises 19% at 

150 ft.”, 2) “APHIS should disclose its quantitative analysis and the percent drift it expects--by 

distance-- into untreated swaths for each application method it proposes”, and 3) “APHIS must 

also specify in its operational procedures the use of nozzles that will result in droplet spectra that 

accord with its analysis”.

The VMD used by APHIS for diflubenzuron is the preferred median diameter used by the 

Program. APHIS recognizes that the range of droplet sizes can vary under a ULV application. 

Comment 24

APHIS received a comment that it is “unrealistic that APHIS can comply with mitigation 

measures designed to protect bees on pesticide labels “(e.g., bumble bees fly earlier and later in 

the day, diflubenzuron is toxic to developing forms, if plants are flowering, bees are active, etc.)

APHIS uses diflubenzuron at far-lower application rates than allowed on the label, thereby 

minimizing risks to non-targets, such as bees. There have been several studies on diflubenzuron 

effects on bees, such as Schroeder et al. (1980) and insect growth regulator effects reviewed 

in Tasei (2001), which support the idea that the diflubenzuron levels APHIS uses for 

grasshoppers and Mormon crickets are a minimal risk to bees. APHIS also complies with any 

label requirements designed to minimize impacts to pollinators.

Comment 25

APHIS received the following comment, “Except for untreated swath widths, the EA is silent on 

how it will avoid impact to pollinators. The EAs do allow for some protections for managed 

pollinators in the Operational Procedures, but wild native pollinators are not even listed as 

"representative species" in Table 1. It has already been shown that within sprayed areas, risk 

quotients at expected application rates would be well above 1.0. Leaving skipped widths is also 

not a full solution at expected widths since, due to drift, untreated swaths are highly likely to be 

exposed to levels above risk quotients”.

APHIS uses diflubenzuron at far-lower levels than allowed by the label, thereby minimizing risks 

to non-targets. Additionally, APHIS commonly incorporates untreated swaths into its treatment 
62

programs, which have consistently demonstrated reduced impacts to non-target arthropods 

(Lockwood et al. (1999, 2001, 2002); Norelius and Lockwood (1999)).

Comment 26

APHIS received one comment regarding that APHIS must not ignore requirements listed on 

pesticide labels, nor make assumptions about its compliance with these when RAATS measures 

that will actually be taken are vague and unspecified.

APHIS complies with all applicable Federal and State pesticide label language when making 

pesticide treatments.

Comment 27

APHIS received the following comment: “While flexibility with these may have been 

appropriate at the EIS stage, it is not appropriate at the EA stage. APHIS must fully disclose its 

RAATS plan for each treatment in the EA, including specifying application method, chemical to 

be used, rate, and width of untreated swaths.”

RAATs are a dynamic treatment method based on the size of the treatment area, species complex, 

and density of target species. Specific details regarding RAATs cannot be determined until site 

specific data is collected during the 2020 survey season and an appropriate chemical is 

identified. Once a treatment is determined necessary, application method, untreated swath 

widths, chemical choice, and application rate are included in the bid for contracting.

Comment 28

APHIS received one comment, “To be consistent with the Pollinator-Friendly BMPs for Federal 

Lands (see Comment 7), APHIS must go beyond the general statements on the pesticide labels 

and specify more exactly how its spray plan will further reduce exposure and risk to bees.”

APHIS implements several BMP practices in their treatment strategies that are designed to 

protect nontarget invertebrates, including pollinators. APHIS minimizes insecticide use by using 

lower than labeled rates for all Program insecticides, alternating swaths during 

treatment, making only one application per season and minimizing use of liquid broad spectrum 

insecticides. APHIS also continues to evaluate new monitoring and control methods designed to 

increase the response to economically damaging populations of grasshoppers and Mormon 

crickets while protecting rangeland resources such as pollinators.

 

Comment 29

APHIS received one comment that the letter of concurrence mentions only two chemicals. It 

appears that no consultation was completed for the use of chlorantraniliprole. APHIS must not 

utilize active ingredients for which consultation is incomplete

APHIS does not make Program treatments without completing consultation under Section 7 of 

the ESA. Chlorantraniliprole is not proposed for use in 2020. The final EA has been updated to 

reflect the changes in the program.
63

Comment 30

APHIS received two comments concerning operationally, how will listed species’ protected 

locations be identified for ground and aerial applicators? How will such locations, buffer widths 

listed in the protective measures, and any specific instructions (i.e. use of carbaryl bait only) for 

some species be mapped and communicated to applicators? APHIS must provide to applicators 

a set of clear set of directions outlining protective measures for the listed and proposed species 

found within this project area and not burden applicators with a confusing set of directions split 

between multiple tables.

In New Mexico, if there is a treatment request, all protected locations will be identified in shape 

files provided to the applicators. Visible ground markings will also be employed.

Comment 31

APHIS received one comment about pesticide specific conservation measures for each listed 

species, where appropriate, should be explicitly addressed and adopted.

Agreed upon mitigation measures address specific chemicals when conservation measures are 

warranted. These measures are agreed upon during the consultation process with the FWS and 

are applied in the field during application.

Comment 32

APHIS received one comment that APHIS should adopt the following operational guideline 

across all site-specific EAs: “Use Global Positioning System (GPS) coordinates for pilot 

guidance on the parameters of the spray block. Ground flagging or markers should accompany 

GPS coordinates in delineating the project area as well as areas to omit from treatment (e.g., 

boundaries and buffers for bodies of water, habitats of protected species, etc.).”

See Comment 30.

Comment 33

APHIS received one comment that, “APHIS states that it has no legal obligation to manage for 

vulnerable species not on the Endangered Species List. The essential role that pollinators play in 

the conservation of listed plant species is not addressed in the EAs and makes no mention of the 

fact that there are affirmative obligations incumbent on federal agencies with regard to protection 

of pollinators, regardless of whether they are federally listed including the 2014 Presidential 

Memorandum, the National Strategy to Promote the Health or Honey Bees and Other 

Pollinators, the Pollinator Friendly BMPs for Federal Land, and the Pollinator Research Action 

Item.”

APHIS considers the role of pollinators in any consultations conducted with the FWS to protect 

federally-listed plants. Mitigation measures, such as no treatment buffers are applied with 

consideration of the protection of pollinators that are important to a particular listed plant 

species.

APHIS also implements several BMP practices in their treatment strategies that are designed to 

protect nontarget invertebrates, including pollinators. APHIS minimizes insecticide use by using 
64

lower than labeled rates for all Program insecticides, alternating swaths during 

treatment, making only one application per season and minimizing use of liquid broad spectrum 

insecticides. APHIS also continues to evaluate new monitoring and control methods designed to 

increase the response to economically damaging populations of grasshoppers and Mormon 

crickets while protecting rangeland resources such as pollinators.

Comment 34

APHIS received one comment regarding, the EAs protections for at risk species, including the 

monarch butterfly which is currently being assessed for listing under the Endangered Species 

Act, are practically non-existent.

While there is no requirement to consult under ESA on sensitive species, APHIS works 

cooperatively with Federal, State and Tribal land managers to implement protection measures, 

where applicable, for species of concern. In addition, land managers can request restrictions 

designed to protect sensitive species or habitats in areas that are proposed for treatment.

Comment 35

APHIS received one comment, “In the face of declining pollinator populations and the existence 

of federal directives for agencies to support and conserve pollinators and their habitat, APHIS 

must not conduct business as usual. APHIS should identify the at-risk pollinator species 

potentially present in the geographic area of the EAs and map their ranges prior to approving any 

treatment requests. Prior to treatment, APHIS should survey for presence of host plants and 

ensure that it has identified specific, actionable measures it will take to protect monarch habitat 

and the habitat of at-risk butterfly species from contamination that may occur as a result of 

exposure to treatment, such as designating a 125-ft buffer around identified habitat. Some ways 

to enact protections for at-risk species above and beyond those included in the EAs include:

● Survey for butterfly host plants and avoid any applications to host plants.

● Time pesticide applications to avoid exposure to at risk species.

● Do not apply pesticides (especially insecticides) when monarchs (adult and immature) are 

present or expected to be present.

● Avoid aerial applications.

● Avoid using malathion and liquid carbaryl.

● Include large buffers around all water sources, including intermittent and ephemeral streams, 

wetlands, and permanent streams and rivers, as well as threatened and endangered species 

habitat, honey bee hives, and any human-inhabited area. For example, Tepedino (2000) 

recommends a three-mile buffer around rare plant populations, as many of these are pollinated 

by solitary bees that are susceptible to grasshopper control chemicals.”

APHIS includes many of the proposed measures to minimize risks to non-target organisms and 

human health. These are summarized in the recent EIS. For example, no treatment buffers are 

applied to all water bodies and to areas where the public may potentially be exposed to Program 

applications. APHIS also minimizes aerial insecticide use, where possible, however site 

conditions may dictate the need for aerial treatments. APHIS minimizes use of liquid carbaryl 

and malathion which is reflected in the historical use for both insecticides. Diflubenzuron has 

been the preferred insecticide for making Program suppression treatments. In addition APHIS 

has incorporated the use of RAATS in the Program as a means to reduce insecticide use 
65

providing reduced risk while meeting the goal of suppression. APHIS continues to research and 

develop new techniques for management of grasshopper and Mormon cricket populations.

Comment 36

APHIS received the following comment, “While the mitigations that are identified for aquatic 

habitats in the EAs are heartening, APHIS should include monitoring for the presence and health 

of mussels in streams that traverse or are adjacent to treatment areas as part of its monitoring 

strategy.”

APHIS conducts environmental monitoring related to Program treatments. Monitoring is 

typically done adjacent to sensitive habitats, including aquatic habitats, to determine pesticide 

residues. These data can be used to determine risk to non-target organisms based on available 

toxicity data.

Comment 37

APHIS received the following comment, “To protect freshwater mussels, APHIS should use the 

same buffers agreed to in the national consultation with NMFS to protect listed salmon to protect 

freshwater mussels.”

APHIS agrees that freshwater mussels should be protected, as well as other aquatic organisms, 

and uses ground and aerial application no treatment buffers adjacent to all aquatic habitats. In 

addition APHIS uses reduced rates of Program insecticides compared to current labeled rates. 

These mitigation measures are beyond label requirements for protection of aquatic habitats. The 

intent of these buffers is to reduce off-site drift and runoff of Program insecticides to aquatic 

habitats. New Mexico will maintain a quarter-mile buffer around any critical habitat for the 

Texas hornshell.

Comment 38

APHIS received the following comment, “The EAs do not discuss water bodies of anthropogenic 

origin, such as stock tanks or stock ponds, nor any buffers that will be observed to prevent 

pesticide overspray or drift into these habitats.”

New Mexico does not directly spray any riparian areas or bodies of water and have implemented 

buffers that exceed label requirements.

Comment 39

APHIS received the following comment, “APHIS should recognize the potential for stock 

pond/tanks to contribute significantly to the diversity of aquatic invertebrates in rangelands.”

See previous response. 

Comment 40

APHIS received the following comment, “APHIS should identify and map all stock tanks/ponds 

and specify a buffer around stock ponds/tanks from chemical treatment at least equivalent to that 

specified for wetlands, in order to protect aquatic diversity.”
66

All bodies of water are buffered according to APHIS Guidelines in Appendix A of EA NM-20-

01.

Comment 41

APHIS received one comment, “APHIS’ reactive strategy includes no mention of what is most 

sorely needed: cooperation and planning with land managers to take appropriate steps to prevent 

the types of grasshopper and cricket outbreaks that are now dealt with by chemical controls.”

APHIS is not a land management agency, but encourages IPM through past and current 

research and will continue to do so.

APHIS supports the use of IPM in the management of grasshoppers and Mormon Crickets. 

APHIS provides technical assistance to Federal, Tribal, State and private land managers 

including the use of IPM. However, implementation of on-the-ground IPM activities is limited to 

land management agencies and Tribes, as well as private land owners. In addition, APHIS’ 

authority under the Plant Protection Act is to treat Federal, State and private lands for 

grasshoppers and Mormon cricket populations. APHIS’ technical assistance occurs under each 

of the three alternatives proposed in the EIS.

In addition to providing technical assistance, APHIS completed the Grasshopper Integrated Pest 

Management (GIPM) project, which is discussed in more detail on page 21 of this EIS. One of 

the goals of the GIPM is to develop new methods of suppressing grasshopper and Mormon 

cricket populations that will reduce non-target effects. RAATs are one of the methods that has 

been developed to reduce the amount of pesticide used in suppression activities, and is a 

component of IPM. APHIS continues to evaluate new suppression tools and methods for 

grasshopper and Mormon cricket populations, including biological control, and as stated in the 

EIS, will implement those methods once proven effective and approved for use in the United 

States.

Comment 42

APHIS received one comment: “Emphasizing cultural techniques through appropriate grazing 

management could help to minimize pesticide application and allow natural enemies to regulate 

grasshopper and Mormon cricket populations to the greatest extent possible. While more 

research is needed to develop species- and region-specific management treatments that use 

alternatives to pesticides (Vermeire et al. 2004), there is likely enough data to employ cultural 

techniques now.”

APHIS supports the use of IPM in the management of grasshoppers and Mormon Crickets. 

APHIS provides technical assistance to Federal, Tribal, State and private land managers 

including the use of IPM, including cultural techniques. However, implementation of on-theground IPM activities is limited to land management agencies and Tribes, as well as private land 

owners. In addition, APHIS’ authority under the Plant Protection Act is to treat Federal, State 

and private lands for grasshoppers and Mormon cricket populations.
67

Comment 43

APHIS received one comment that, “APHIS must elevate the expectation of preventative 

approaches in its cooperative agreements with other land management agencies. APHIS can 

collaborate with agencies (such as the Natural Resource Conservation Service (NRCS), the Farm 

Service Agency (FSA), and State Extension program) to facilitate discussion and disseminate 

information to ranchers about preventative measures that can be taken and alternatives to 

pesticide use.”

APHIS supports the use of IPM in the management of grasshoppers and Mormon Crickets. 

APHIS provides technical assistance to Federal, Tribal, State and private land managers 

including the use of IPM, including cultural techniques. However, implementation of on-theground IPM activities is limited to land management agencies and Tribes, as well as private land 

owners. In addition, APHIS’ authority under the Plant Protection Act is to treat Federal, State 

and private lands for grasshoppers and Mormon cricket populations.

APHIS has maintained cooperative relationships with state and federal land managers as well as 

private landowners and Indian tribes for decades. Those relationships have allowed APHIS to 

provide consistent and continual recommendations on land management practices designed 

to mitigate the damage from orthopteran infestations.

Comment 44

APHIS received on comment that, “APHIS and/or collaborating agencies should investigate and 

implement opportunities to incentivize healthy range management practices.”

As part of its ongoing IPM strategy to manage grasshoppers and Mormon cricket outbreaks, 

APHIS collaborates with scientists and land managers focused on rangeland health.

Comment 45

APHIS received one comment that, “APHIS and its partners should be approaching the problem 

by keeping a focus on the potential to reduce grasshopper carrying capacity by making the 

rangeland environment less hospitable for the pests. APHIS must not take a limited view of its 

role and responsibilities, and should utilize any available mechanism to require land management 

agencies to diminish the severity, frequency and duration of grasshopper outbreaks by utilizing 

cultural management actions. Memoranda of Understanding (MOUs) should be examined and 

updated to ensure that land management agencies are accountable in utilizing cultural techniques 

to diminish the carrying capacity of pest species.

APHIS supports the use of IPM in the management of grasshoppers and Mormon Crickets. 

APHIS provides technical assistance to Federal, Tribal, State and private land managers 

including the use of IPM. However, implementation of on-the-ground IPM activities is limited to 

land management agencies and Tribes, as well as private land owners. In addition, APHIS’ 

authority under the Plant Protection Act is to treat Federal, State and private lands for 

grasshoppers and Mormon cricket populations.
68

Comment 46

APHIS received on comment that “APHIS can collaborate with agencies (such as the Natural 

Resource Conservation Service (NRCS), the Farm Service Agency (FSA), and State Extension

program) to facilitate discussion and disseminate information to ranchers about preventative 

measures that can be taken and alternatives to pesticide use.”

New Mexico PPQ conducts outreach to stakeholders encouraging them to visit the ARS website 

to review the information available. Our hope is that they take measures to lessen the likelihood 

of treatments being necessary. This year PPQ made presentations to ranchers at strategic 

locations through NMDA Extension service.

Comment 47

APHIS received a comment, “Longer-term strategic thinking should include:

●Prevent conditions that allow pest populations to survive and reproduce.

● Employ diverse management techniques (e.g., biological, physical, and cultural).

● Select pesticides to minimize risks to nontarget organisms.

● Implement frequent and intense monitoring to identify populations that can be controlled with 

small ground-based pesticide application equipment.

● Monitor sites before and after application of any insecticide to determine the efficacy of the 

pest management technique as well as if there is an impact on water quality or non-target 

species.”

APHIS currently monitors for grasshopper and Mormon cricket populations. These measures 

are employed to allow APHIS to respond with treatment, where warranted, treating the smallest 

area possible and if practical using ground-based equipment. APHIS, due to its monitoring 

efforts, has been able to rely on diflubenzuron as the primary insecticide used in the Program.

Diflubenzuron is a more selective insecticide compared to carbaryl and malathion posing less 

risk to nontarget organisms. APHIS also uses environmental monitoring to assess application 

success and to determine if Program insecticides are reaching sensitive habitats, including 

aquatic habitats. APHIS supports the use of IPM in the management of grasshoppers and 

Mormon Crickets. APHIS provides technical assistance to Federal, Tribal, State and private 

land managers including the use of IPM. However, implementation of on-the-ground IPM 

activities is limited to land management agencies and Tribes, as well as private land owners. In 

addition, APHIS’ authority under the Plant Protection Act is to treat Federal, State and private 

lands for grasshoppers and Mormon cricket populations. APHIS continues to research and 

develop new methods for assessing and controlling grasshopper and Mormon cricket 

populations that can be incorporated into IPM practices. 

Comment 48

APHIS received one comment that, “The EAs do not make mention of any specific protections to 

be accorded to special status lands such as Wilderness areas, Wilderness study areas, Research 

Natural Areas, National Wildlife Refuges, and designated or proposed Areas of Critical 

Environmental Concern. These special status areas have been designated for specific purposes 

and generally discourage human intervention with the natural ecosystem. Grasshopper 

suppression should not be undertaken in such areas.”
69

APHIS does not make treatments on lands of special status without a request from that agency 

and an evaluation of the whether treatments are necessary. Additional protection measures for 

these types of lands are established by the agency requesting treatment and are followed by 

APHIS.

Comment 49

APHIS received one comment that, “APHIS has not posted the Draft EAs in the last several 

years, but limiting public notice is contrary to the spirit of the NEPA process.”

New Mexico has consistently published, annually, draft EA’s in local and statewide newspapers 

(more than one).

Comment 50

APHIS received the following comment regarding, “We appreciate that public notice of this sitespecific EA and its comment period was posted at the APHIS website. It does not appear to have 

been the practice to post the Draft EAs in the last several years, but limiting public notice is 

contrary to the spirit of the NEPA process. Grasshopper suppression efforts are of more than 

local concern and as federal actions, should be noticed properly, i.e. beyond local stakeholder 

audiences, local newspapers, etc. We recommend that, in the future, notice of open public 

comment periods for all site-specific EAs for grasshopper suppression be posted in the Federal 

Register, and documents made available for review at regulations.gov and at the APHIS 

grasshopper website.”

Public involvement under the CEQ Regulations for Implementing the Procedural Provisions of 

NEPA distinguishes federal actions with effects of national concern from those with effects 

primarily of local concern (40 CFR 1506.6). Our EIS process for the grasshopper and Mormon 

cricket suppression program was published in the Federal Register (APHIS-2016-0045), and met 

all applicable notice and comment requirements for a federal action with effects of national 

concern. This process provided individuals and national groups the ability to participate in the 

development of alternatives and provide comment. Our subsequent state-based actions have the 

potential for effects of local concern, and we publish them according to the provisions that apply 

to federal actions with effects primarily of local concern. This includes the USDA APHIS NEPA 

Implementation Procedures, which allows for EAs and FONSIs where the effects of an action are 

primarily of regional or local concern to normally provide publication in a local or area 

newspaper of general circulation (7 CFR 372.7(b)(3)). These publications provide potentially 

locally-affected individuals an additional opportunity to provide input into the decision-making 

process. Some states also provide additional opportunities for local public involvement, such as 

public meetings.

Comment 51

APHIS received the following comments, “The Draft Environmental Assessments Frustrate 

Public Participation.” “APHIS frustrated public participation by failing to inform interested 

parties of the existence of the EAs.”
70

“Scoping” is the process APHIS uses through which the agency and the public identify 

alternatives and issues to be considered during the development of a grasshopper or Mormon 

cricket suppression program. Scoping was helpful in the preparation of the draft Environmental 

Assessments (EAs). The process can occur formally and informally through meetings, 

conversations, or written comments from individuals and groups.

Prior to the treatment season, APHIS conducted meetings or provided guidance for public 

participation in the decision making process. In addition, APHIS private landowners of the 

potential for grasshopper and Mormon cricket outbreaks on their lands.

USDA-APHIS-PPQ Field Operations in New Mexico advertised in two papers, the Albuquerque 

Journal and the Roswell Daily Record, three different days over a one week period. The first 

notice was published March 18th, 2020 and the comment period ended on April 23rd, 2020. The 

newspaper advertisement did have a link and local contact information. 

Comment 52

APHIS received the following comment, “APHIS did not providing information for the 

submission of public comments including where and when to submit comments by.”

APHIS works to inform all interested parties about draft EA’s for comment. When an interested 

party asks to be informed, APHIS ensures contact information is added to the list of interested 

stakeholders. Each local office works to inform interested parties of the availability of an EA for 

comment. Any omission of an interested party is not intentional. 

USDA-APHIS-PPQ Field Operations in New Mexico included in the newspaper advertisement, a 

link and local contact information.

Comment 53

APHIS received the following comments, “APHIS limited public notice to local papers.” “This 

local notice is insufficient as it excludes countless other interested parties.”

Public involvement under the CEQ Regulations for Implementing the Procedural Provisions of 

NEPA distinguishes federal actions with effects of national concern from those with effects 

primarily of local concern (40 CFR 1506.6). Our EIS process for the GMC program was 

published in the Federal Register (APHIS-2016-0045), and met all applicable notice and 

comment requirements for a federal action with effects of national concern. This process 

provided individuals and national groups the ability to participate in the development of 

alternatives and provide comment. Our subsequent state-based actions have the potential for 

effects of local concern, and we publish them according to the provisions that apply to federal 

actions with effects primarily of local concern. This includes the USDA APHIS NEPA 

Implementation Procedures, which allows for EAs and FONSIs where the effects of an action are 

primarily of regional or local concern to normally provide publication in a local or area 

newspaper of general circulation (7 CFR 372.7(b)(3)). These publications provide potentially 

locally-affected individuals an additional opportunity to provide input into the decision-making 

process. Some states also provide additional opportunities for local public involvement, such as 

public meetings.
71

Comment 54

APHIS received the following comments, “APHIS provided a short public comment period 

during this COVID-19 pandemic.” “The 30 day comment deadline for the Draft EAs is wholly 

inappropriate during the current COVID-19 pandemic, where both staff and members of the 

concerned public have limited capacity, given the challenges associated with a global pandemic 

including but not limited to increased childcare demands, illness, etc.”

The comment period was in accordance with CEQ regulations, 40 C.F.R. § 1501.4(e) (2), in 

determining whether to prepare an environmental impact statement the Federal agency shall: (e) 

Prepare a finding of no significant impact, if the agency determines on the basis of the 

environmental assessment not to prepare a statement. (2) In certain limited circumstances, which 

the agency may cover in its procedures under § 1507.3, the agency shall make the finding of no 

significant impact available for public review (including State and area-wide clearinghouses) for 

30 days before the agency makes its final determination whether to prepare an environmental 

impact statement and before the action may begin. CEQ guidance also notes: When preparing 

an EA, the agency has discretion as to the level of public involvement. The CEQ regulations state 

that the agency shall involve environmental agencies, applicants, and the public, to the extent 

practicable, in preparing EAs. Sometimes agencies will choose to mirror the scoping and public 

comment periods that are found in the EIS process. In other situations, agencies make the EA 

and a draft FONSI available to interested members of the public. APHIS would have 

considered extending the comment period if there had been a reason to believe that additional 

substantive issues remained, or that the pandemic itself created new issues.

USDA-APHIS-PPQ New Mexico Field Operations ran an advertisement in two statewide 

newspapers on March 18th and March 22nd and noted that the comment period would end April 

23rd, 2020. 

Comment 55

APHIS received the following comment, “the proposal in question is controversial and deals 

with issues of significant public interest.”

APHIS is not aware of any controversy in the program. Every year APHIS works with local 

stakeholders to gather information and discuss the grasshopper program. The grasshopper 

program requires a written request to treat on any land and discussions with the land owner or 

manager determine the course of the final action. APHIS acts in partnership with stakeholders 

through agreements and Memorandum of Understanding on all activities in the program.

New Mexico has not received any concerns about pesticide use, we do receive concerns and 

requests in regards to infestations of grasshoppers that can significantly reduce forage for 

livestock and impact wildlife.

Comment 56

APHIS received the following comment, “The Draft EAs also limit public participation by 

failing to provide contact information for the submission of written or electronic comments.”
72

The local offices send out public notices to a list of stakeholders that they have collected over the 

years and also announced the open comment period in the local media. Those notices have the 

link for the EA’s and the point of contact. In an attempt to be more transparent APHIS 

has also placed Program EA’s on to the APHIS website for the public to access. When an 

interested party asks to be informed, APHIS ensures their contact information is added to the list 

of interested stakeholders. Each local office works to inform interested parties of the availability 

of an EA for comment. Any omission of an interested party is not intentional. 

New Mexico’s contact information was provided on NM’s public announcement: “Waleska 

Ramirez SPHD, 270 South 17th Street, Las Cruces, NM 88005, Phone # 1-575-527-6985”. In 

the future we will also include e-mail addresses.

Comment 57

APHIS received the following comment, “Nowhere on the webpage for the Draft Environmental 

Assessment Rangeland Grasshopper and Mormon Cricket Suppression Program is there any 

information on where to submit comments.”

The local offices send out public notice to a list of stakeholders that they have collected over the 

years and they also announce the open comment period in the local media. Those notices have 

the link for the EA’s for comment and the point of contact. In an attempt to be more 

transparent APHIS has also placed Program EA’s on its website. When an interested party asks 

to be informed, APHIS ensures their contact information is added to the list of interested 

stakeholders. Each local office works to inform interested parties of the availability of an EA for 

comment. Any omission of an interested party is not intentional. (See Previous Response).

Comment 58

APHIS received the following comment, “Staff for USDA-APHIS that have been involved with 

the environmental review for this program were unable to readily provide information for the 

submission of public comment.”

The local offices send out public notice to a list of stakeholders that they have collected over the 

years and they also announce the open comment period in the local media. Those notices have 

the link for the EA’s for comment and the point of contact. In an attempt to be more 

transparent, we have put all of our EA’s on to the website for people to access. When an 

interested party asks to be informed APHIS ensures their contact information is added to the list 

of interested stakeholders. Each local office works to inform interested parties of the availability 

of an EA for comment. Any omission of an interested party is not intentional. Contact 

information for New Mexico’s EA is on the cover page of the Draft EA. Also, on page 3 of the 

EA, the contact address of the New Mexico Field Operations State Office is listed for copies of 

all documentation. The two legal notices that were published state the website and address 

for obtaining copies the EA and where to send comments.

APHIS is not aware of the direct personnel communication cited by the commenter. APHIS

personnel are engaged in a wide variety of activities to protect American agriculture and not 
73

every staff member is completely informed about the details of the Grasshopper Program NEPA 

compliance procedures.

Comment 59

APHIS received the following comment, “there is no information on when the comment period 

opened or closed on the EAs provided on the webpage.”

This information was included in New Mexico’s public announcement:

“LEGAL NOTICE 

The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS), 

Plant Protection and Quarantine, is making available to the public an environmental assessment 

for Federal Involvement in the State of New Mexico Rangeland Grasshopper and Mormon 

Cricket Suppression Program. Persons wishing to obtain a copy of the documents can visit the 

APHIS website (https://www.aphis.usda.gov/aphis/ourfocus/planthealth/plant-pest-and-diseaseprograms/sa_environmental_assessments/grasshopper-cricket ) or contact Waleska Ramirez 

SPHD, 270 South 17th Street, Las Cruces, NM 88005, Phone # 1-575-527-6985. Inquiries 

should request the environmental assessment for the State of New Mexico Rangeland 

Grasshopper and Mormon Cricket Suppression Program, Environmental Assessment, March 

2020.

Persons wishing to comment on the documents should send the comments to the above address 

by April 23, 2020 by close of Business of this date.”

Comment 60

APHIS received the following comment, “With the EAs dated March 3, 2020 and March 4, 

2020, respectively, a reasonable person could have easily concluded that a 30 day comment 

period ended on April 3, 2020 or April 4, 2020, respectively, rather than the April 15, 2020 

comment deadline.”

See previous response.

Comment 61

APHIS received the following comment, “APHIS has failed to comport with NEPA’s threshold 

requirements.”

APHIS did not fail to perform NEPA’s threshold requirements for public outreach and 

engagement, but rather exceeded them. See previous comments concerning how APHIS informed 

interested parties of the availability of EAs for public comment, including public meetings, where 

to send comments, and the closing date for the comment period.

Comment 62

APHIS received the following comment, “The Draft EAs further limit public participation by 

failing to post notices in the Federal Register or on regulations.gov, unlike earlier versions of the 

environmental review.”

APHIS further involves the public in the scoping process by the publication of notices of 

availability for EAs and a Findings of No Significant Impact (FONSIs). When an individual State 
74

level EA is written, a notice is published in the legal section of the local newspaper, advertising 

the availability of the EA during an open comment period. The notices published in local 

newspapers was conducted in accordance with APHIS’ NEPA Implementation Procedures, 

372.7 (b)(3), Notification of the availability of environmental assessments and findings of no 

significant impact for proposed activities will be published in the FEDERAL REGISTER, unless 

it is determined that the effects of the action are primarily of regional or local concern. Where 

the effects of the action are primarily of regional or local concern, notice will normally be 

provided through publication in a local or area newspaper of general circulation and/or the 

procedures implementing Executive Order 12372, “Intergovernmental Review of Federal 

Programs.”

Public involvement under the CEQ Regulations for Implementing the Procedural Provisions of 

NEPA distinguishes federal actions with effects of national concern from those with effects 

primarily of local concern (40 CFR 1506.6). Our EIS process for the GMC program was 

published in the Federal Register (APHIS-2016-0045), and met all applicable notice and 

comment requirements for a federal action with effects of national concern. This process 

provided individuals and national groups the ability to participate in the development of 

alternatives and provide comment. Our subsequent state-based actions have the potential for 

effects of local concern, and we publish them according to the provisions that apply to federal 

actions with effects primarily of local concern. This includes the USDA APHIS NEPA 

Implementation Procedures, which allows for EAs and FONSIs where the effects of an action are 

primarily of regional or local concern to normally provide publication in a local or area 

newspaper of general circulation (7 CFR 372.7(b)(3)). These publications provide potentially 

locally-affected individuals an additional opportunity to provide input into the decision-making 

process. Some states also provide additional opportunities for local public involvement, such as 

public meetings.

Comment 63

APHIS received the following comment, “[The Center for Biological Diversity] have 

been informed that there was notice in local newspapers. This local notice is insufficient as it 

excludes countless other interested parties.”

See previous response

Comment 64

APHIS received the following comment, “APHIS has failed to meet NEPAs requirements for 

public involvement in these EAs.”

APHIS also notes CEQ guidance for public involvement in the NEPA process of agencies, “A 

Citizen’s Guide to the NEPA” states: “When preparing an EA, the agency has discretion as to 

the level of public involvement. The CEQ regulations state that the agency shall involve 

environmental agencies, applicants, and the public, to the extent practicable, in preparing EAs. 

Sometimes agencies will choose to mirror the scoping and public comment periods that are 

found in the EIS process. In other situations, agencies make the EA and a draft FONSI available 

to interested members of the public”.
75

Some agencies, such as the Army, require that interested parties be notified of the decision to 

prepare an EA, and the Army also makes the EA publicly available. Some agencies keep a 

notification list of parties interested in a particular kind of action or in all agency actions. Other 

agencies simply prepare the EA.

Contact information for the APHIS-PPQ New Mexico state office is on the cover page of the 

Draft EA’s. The notice of public comment clearly stated the website and Address for EA 

documents and where to send comments and the closing date of April 23rd, 2020.

Comment 65

APHIS received the following comment, “the range of alternatives offered by APHIS is woefully 

inadequate.”

APHIS structured and analyzed the risk of the substantial program alternatives available to the 

agency. Alternatives, including those excluded from further analysis, were discussed in the final 

EIS.

Comment 66

APHIS received the following comment, “[The alternatives] are, “No Action,” “Insecticide 

Applications at Conventional Rates or Reduced Agent Area Treatments with Adaptive 

Management Strategy” (preferred alternative) and “Experimental Treatments Alternative. While 

the RAATs are an improvement over conventional approval rates, this alternative should actually 

be two, one, Insecticide Applications at Conventional Rates and two, Reduced Agent Area 

Treatments with Adaptive Management Strategy. Lumping the two together means that 

supporting this alternative could mean pesticide application at conventional rates without 

RAATs. APHIS must break these into different alternatives.”

The EA states “Under Alternative A, the No Action alternative, APHIS would not conduct a 

program to suppress grasshopper infestations. Under this alternative, APHIS may opt to provide 

limited technical assistance, but any suppression program would be implemented by a Federal 

land management agency, a State agriculture department, a local government, or a private 

group or individual.”

Under Alternative B, the Preferred Alternative, APHIS would manage a grasshopper treatment 

program using potentially any of pesticides and application methods described in the EA 

Alternative B to suppress outbreaks. The grouping of conventional methods and pesticide rates 

with the more commonly used RAATs procedures reflects the variety of approaches that the 

agency may need depending on treatment specific circumstances.

Comment 67

APHIS received the following comment, “APHIS does not include an alternative that utilizes 

Integrated Pest Management.”

APHIS technical guidance is part of each alternative proposed, and is not unique to any one 

alternative. An example of APHIS technical guidance is the agency’s work on integrated pest 
76

management (IPM) for the grasshopper program. IPM for grasshoppers includes biological 

control, chemical control, rangeland and population dynamics, and decision support tools.

APHIS has funded the investigation of various integrated pest management (IPM) strategies for 

the grasshopper program. Congress established the Grasshopper Integrated Pest Management 

(GIPM) to study the feasibility of using IPM for managing grasshoppers.

The major objectives of the APHIS GIPM program were to: 1) manage grasshopper populations 

in study areas, 2) compare the effectiveness of an IPM program for rangeland grasshoppers with 

the effectiveness of a standard chemical control program on a regional scale, 3) determine the 

effectiveness of early sampling in detecting developing grasshopper infestations, 4) quantify 

short- and long-term responses of grasshopper populations to treatments, and 5) develop and 

evaluate new grasshopper suppression techniques that have minimal effects on non-target 

species (Quinn, 2000). The results for the GIPM program have been provided to managers of 

public and private rangeland including ways to manage grasshopper populations in the longterm, such as livestock grazing methods and cultural control by farmers.

APHIS issued the GIPM User Handbook describing biological control, chemical control, 

environmental monitoring and evaluating, modeling and population dynamics, rangeland 

management, decision support tools, and future directions.

Federal and State land management agencies, State agriculture departments, and private groups 

or individuals may carry out a variety of preventative IPM strategies that may reduce the 

potential for grasshopper outbreaks. Some of these activities include grazing management 

practices, cultural and mechanical methods, and prescribe-burning of rangeland areas. These 

techniques have been tried with varying success in rangeland management, and some have been 

associated with the prevention, control, or suppression of harmful grasshopper populations on 

rangeland.

Regardless of the various IPM strategies taken, the primary focus of the risk analysis contained 

in the EAs is on the potential impacts from chemical treatments needed during an outbreak of 

economic importance. While APHIS provides technical expertise regarding grasshopper 

management actions, the responsibility for implementing most land management practices lies 

with other Federal (i.e., BIA, BLM, and USDA’s FS), State, and private land managers.

The final EA will be updated to reflect APHIS support for IPM strategies in the grasshopper and 

Mormon cricket suppression program.

Comment 68

APHIS received the following comment, “Given that much of APHIS’s work on grasshopper and 

Mormon cricket suppression is on lands managed by DOI or USDA or adjacent to federal public 

lands in Arizona, it only makes sense that it would conform to their IPM mandates in these 

EAs.” 

See previous response. APHIS supports the use of IPM to prevent grasshopper outbreaks on or 

near Federal lands. These actions are and should continue to be considered by agencies as part
77

of proper land management. APHIS treatments are a component of the IPM strategies that may 

be employed by Federal land management agencies. APHIS also adheres to any restrictions 

proposed by Federal or State land management agencies that may be part of their IPM 

strategies. 

Comment 69

APHIS received the following comment, “APHIS must adopt an alternative that harmonizes its 

mandates in regard to grasshoppers and Mormon crickets with the IPM mandates of the federal 

lands that it operates on.”

See previous response. A Memorandum of Understanding between land management agencies, 

i.e., the Department of Interior’s Bureau of Indian Affairs and Bureau of Land Management, and 

USDA’s Forest Service, indicates that while APHIS provides technical expertise, namely advice, 

regarding grasshopper management actions, the responsibility for implementing most land 

management practices, including IPM measures, lies with other Federal (i.e., BIA, BLM, and 

USDA’s FS), State, and private land managers (page 32 of the 2019 EIS).

Comment 70

APHIS received the following comment, “APHIS must enlist IPM experts to craft an alternative 

that is land-use and pest-specific, using the minimum level of pest suppression necessary, relying 

on prevention, avoidance, monitoring, and suppression techniques in order to decrease pest 

pressure with the least harmful controls possible.”

See comment 67.

Comment 71

APHIS received the following comment, “APHIS must conduct an adequate analysis of human 

health effects.”

APHIS prepared and published separate Final Human Health and Ecological Risk Assessments 

for all the pesticides used by the Grasshopper Programs (November 2019).

Adherence to label requirements and additional Program measures designed to reduce exposure 

to workers (e.g., PPE requirements include long-sleeved shirt and long pants and shoes plus 

socks) and the public (e.g., mitigations to protect water sources, mitigations to limit spray drift, 

and restricted-entry intervals) result in low health risk to all human population segments.

Comment 72

APHIS received the following comment, “there is no description of how APHIS plans to identify 

or contact these individuals in order to advise them to avoid treatment areas.”

In areas considered for treatment, State-registered beekeepers and organic producers shall be 

notified in advance of proposed treatments. APHIS will notify residents within treatment areas, 

or their designated representatives, prior to proposed operations, and advise them of the control 

method to be used, proposed method of application, and precautions to be taken.
78

Comment 73

APHIS received the following comment, “APHIS’s failure conduct any analysis of their impacts 

to human health is a far cry from the level of analysis demanded by NEPA and basic due care for 

public health.” 

See responses to comment 73. APHIS prepared and published separate Final Human Health and 

Ecological Risk Assessments for all the pesticides used by the Grasshopper Programs 

(November 2019). These documents were incorporated by reference into the draft EA.

Comment 74

APHIS received the following comment, “APHIS fails to look at the effects of the proposed 

action on migratory birds.”

Executive Order 13186 directs Federal agencies taking actions with a measurable negative 

effect on migratory bird populations to develop and implement a Memorandum of Understanding 

with the USFWS that promotes the conservation of migratory bird populations. On August 2, 

2012, a Memorandum of Understanding between APHIS and the USFWS was signed to facilitate 

the implementation of this Executive Order.

Specifically to the grasshopper and Mormon cricket program, APHIS evaluated potential 

impacts to birds in the final EIS and associated human health and ecological risk assessments.

These documents are incorporated by reference into the final EA.

Comment 75

APHIS received the following comment, “APHIS needs to take a hard look at the impacts of the 

proposed action, including direct and indirect effects.”

The EA incorporated the analysis from the EIS and associated human health and ecological risk 

assessments into the analysis. The EIS, and in particular, the risk assessments evaluated 

potential indirect effects to non-target organisms, relying on available toxicity data and 

estimates of risk. 

Comment 76

APHIS received the following comment, “A direct effect of not spraying insecticides is abundant 

food for migratory birds. Conversely, a direct effect of spraying is reduced abundance of food for 

insectivorous migratory birds. Another potential direct effect of insecticide spraying is 

poisoning. An example of an indirect effect is the cumulative effect of continuous low level 

pesticide exposure from numerous sites over many years. APHIS must take a hard look at all 

these impacts”.

APHIS prepared and published separate Final Human Health and Ecological Risk Assessments 

for all the pesticides used by the Grasshopper Programs (November 2019). The risk assessments 

discuss the risk to birds for each program insecticide. Available laboratory and field effects data 

were used to evaluate risks to birds through direct exposure as well as indirect effects that could 

result from the loss of prey items such as terrestrial arthropods.
79

Comment 77

APHIS received the following comment, “APHIS’s handling of impacts to non-target species 

and species of concern wholly fails to meet NEPA’s requirement that the agency take a hard look 

at the impacts of its proposed action.”

APHIS prepared and published separate Final Human Health and Ecological Risk Assessments 

for all the pesticides used by the grasshopper and Mormon cricket suppression 

program (November 2019). The EIS and risk assessments evaluated available effects data and 

risk to non-target species. These documents are incorporated by reference into the final EA. The 

risk assessments provided the basis for summary statements in the EA that is tiered to the EIS.

Comment 78

APHIS received the following comments, “the EA cannot be finalized until APHIS actually 

takes a hard look at the impacts on non-target and species of concern” and “There is zero detail 

or analysis of how the proposed action would affect a single one of these species. APHIS’s 

attempt to lump all living beings in New Mexico into this statement is absurd. For example, with 

zero analysis, how do we know that the species will “not be excessively affected.” What is the 

threshold for “excessively affected?” This fails to meet NEPA’s most basic disclosure or analysis 

requirements.”

APHIS prepared and published separate Final Human Health and Ecological Risk Assessments 

for all the pesticides used by the grasshopper and Mormon cricket suppression program 

(November 2019). The EIS and risk assessments evaluated available effects data and risk to nontarget species. These documents are incorporated by reference into the final EA. The risk 

assessments provided the basis for summary statements in the EA that is tiered to the EIS.

Comment 79

APHIS received the following comment, “APHIS doesn’t even mention a single sensitive 

species by name. There are hundreds or perhaps even thousands of sensitive or culturally 

important species in New Mexico. For example, New Mexico is a key migratory corridor for 

monarch butterflies.”

APHIS prepared and published separate Final Human Health and Ecological Risk Assessments 

for all the pesticides used by the Grasshopper Programs (November 2019). The risk assessments 

and EIS considered available field and laboratory data regarding impacts to Lepidoptera, 

including moths and butterflies. 

Comment 80

APHIS received the following comments, “APHIS also doesn’t consider the impacts of spraying 

on the incredible diversity of native bee species that reside in New Mexico, including many that 

are exceedingly rare.” and “Grasshopper spraying season is precisely when bees are flying. New 

Mexico is home to over 500 species of native bees. Many of these species are narrow endemics. 

Insecticide spraying done in the wrong place at the wrong time could have the tragic and 

unintended consequence of out an entire population of a species, or even driving extinct a rare 

species, perhaps even one that has never been named.”
80

APHIS works with Tribal, Federal and State land managers and their local biologists, natural 

resource specialists, and range conservationists to implement measures that reduce risks of 

Program treatments to native bees. These measures may include reduced insecticide applications 

associated with RAATS, avoidance measures and use of carbaryl bait, where applicable. 

APHIS also prepared and published separate Final Human Health and Ecological Risk 

Assessments for all the pesticides used by the Grasshopper Programs (November 2019). The risk 

assessments summarized available effects data for nontarget species including pollinators.

Comment 81

APHIS received the following comment, “The EAs have not adequately analyzed the cumulative 

impacts of the program with other governmental or private entity actions.”

APHIS discussed the potential of overlapping chemical treatments in the areas where outbreaks 

of grasshoppers have occurred or could occur in the future in the cumulative impacts section of 

the draft EIS, from page 79 to 83. It is unlikely there would be significant overlap between 

APHIS programs and the grasshopper program and coordinated treatments would mitigate 

impacts if there is ever overlap; current label and mitigations minimize significant exposure of 

soil, water, and air to Program insecticides; grasshopper chemical treatments are not expected 

to persist or bioaccumulate in the environment; and, there is a lack of significant routes of 

exposure (page 82 to 83 of draft EIS).

We are unaware of any retreatment that would occur in an area where APHIS has conducted 

a treatment. Generally, the land that APHIS treats is a hybrid of BLM rangeland and absentee 

landowners leasing land for grazing. Private landowners do not actively manage that land 

and, therefore, are not expected to be making any other types of chemical treatments.

Although APHIS is unaware of any, BLM could potentially do herbicide treatments in areas we 

treat, but they would not treat for GHMC. The cumulative impacts section was updated in the 

final EA to reflect the potential for other land management activities.

Comment 82

APHIS received the following comment, “The EA does not take into account the background 

level of exposure to humans and animals from pesticides and other pollutant sources that exist in 

the environment from other actions or the synergistic effects of the enhanced toxicity that many 

mixtures exhibit.”

The land managers that manage the areas covered in the EAs, document all pesticide 

applications. The activities, or lack thereof, are discussed in the cumulative impacts section of 

the final EA.

The commenter assumes that the rangeland in New Mexico, which is covered by the Draft EA 

NM-20-01, has been exposed to pesticides and pollutants and that there is a synergistic effect 

which enhances toxicity to the environment. New Mexico does have a mosquito control program 

but these programs, almost exclusively, occur in urban areas, not rangeland.
81

Comment 83

APHIS received the following comment, “[the EA] does not account for the range of cumulative 

exposures that would be anticipated. There was no mention of widespread mosquito spraying 

that takes place in many areas.”

See previous comment.

Comment 84

APHIS received the following comment, “as cattle are grazing these pesticides will be washed 

off their bodies or excreted through waste and contaminate surrounding land and water bodies.”

The label for Dimilin 2L specifies that there are no grazing restrictions. Any pesticide residues 

that may be present on forage in treated areas after treatment is typically metabolized and 

excreted as metabolites that have lower toxicity than the parent compound. In addition, the low 

application rates employed by APHIS, relative to the current maximum labelled rates for each 

Program insecticide, would result in very low residues in livestock waste. 

Comment 85

APHIS received the following comment, “A substantial acreage of rangeland is adjacent to lands 

used for plant agriculture, and the EAs state that they also aim to protect these agricultural lands. 

These areas generally have a high potential for crossover contamination through drift or runoff of 

pesticides. Large quantities of pesticides, including insecticides and fungicides that may be 

synergistic with the insecticides included in the EAs, may be used on these lands. In addition, 

herbicide use on crops already significantly impacts insects by destroying habitat and food 

sources in agricultural lands”.

New Mexico has not conducted a program since 1986, nonetheless, cropland areas in proximity 

to rangeland being considered for a program will not be treated and any recommended buffers 

will be adhered to. This EA does discuss crop protection from grasshopper migrations from 

rangeland to adjacent crops (see pages 5, 6, 15 and 24).

 

Comment 86

APHIS received the following comment, “None of these issues were disclosed or analyzed in the 

Draft EIS and add to the already large cumulative exposures from pesticides used in 1) the boll 

weevil eradication program, 2) fruit fly cooperative eradication program, 3) the gypsy moth 

cooperative eradication program, and 4) invasive plant control”.

The commenter refers to the Draft EIS. The EIS has been finalized and the ROD has been 

signed. The final EIS does address the cumulative exposures from other APHIS programs on a 

programmatic level. The documents in question are the Draft EA’s. 

There is no geographical overlap in New Mexico, now or in the foreseeable future, 

between pesticide applications of the Grasshopper Program and the pest control programs 

mentioned by the commenter.
82

Comment 87

APHIS received the following comment, “These cumulative exposures cannot only adversely 

affect human and environmental health but can also negatively impact biological control 

programs that try to manage insect and weed pests with natural predators”.

The Grasshopper Program personnel also the lead biocontrol program personnel and 

cooperators in New Mexico and are well aware of the locations of biocontrol programs. All 

grasshopper treatments are coordinated with the land managers and other non-grasshopper 

programs are discussed if the land managers are concerned about an overlap with other 

programs. New Mexico personnel will work closely with New Mexico Department of 

Agriculture, New Mexico State University and Extension Agents as needed.

Comment 88

APHIS received the following comment, “How these pesticides act in conjunction with one 

another to additively or synergistically increase toxicity is not discussed and no mitigation 

measures were proposed. Therefore, APHIS must fully analyze the impacts from cumulative 

exposures and identify ways in which risk can be mitigated or prohibited”.

The Grasshopper Program does not apply treatments more than once per year to any rangeland 

area. Cumulative exposures from pesticides applied by external parties are not anticipated in 

most cases due to coordination between APHIS, land managers and other cooperators, on 

rangeland that may be receive grasshopper or Mormon cricket treatments. The EA details many 

procedures APHIS employs to mitigate risk.

Comment 89

APHIS received the following comment, “The project is vague and ill-defined, it improperly 

precludes the disclosure of environmental effects because the information on the project and its 

impacts is incomplete”.

The proposed Grasshopper treatment program described in the EA could occur within a specific 

area, using a limited number of insecticides and application methods. The environmental 

consequences of suppressing or not suppressing grasshopper infestations are analyzed in the EA 

and other programmatic risk analysis documents.

Comment 90

APHIS received the following comment, “APHIS’s explanation of a “level of economic 

infestation,” which is the trigger for insecticide spraying, does not give the public any sense 

whatsoever of when that threshold is met. The definition is too vague and ill-defined to meet 

NEPA’s purposes and mandates. The agency could spray with minimal infestation levels if it 

saw fit whenever it decided to do so. There must be a more concrete definition that identifies 

specific thresholds that must be met for the agency to determine an economic level of infestation 

has been met”.

APHIS utilizes and provides links to extensive resources for determining when a grasshopper 

outbreak is exceeding IPM thresholds including, “a level of economic infestation”. The Purpose 
83

and Needs section of the EA and supporting documents adequately define the multiple factors 

that must be evaluated before APHIS decides a treatment is necessary.

Comment 91

APHIS received the following comment, “The EA’s description of the preferred alternative that 

includes “reduced agent area treatments” (“RAATs”) is similarly vague and ill defined”.

RAATs has long been in use, is public knowledge, and one of APHIS’s preferred IPM strategies, 

supported by decades of research. Skipping swaths are the most common RAATs choice, leaving 

50% of the treated area untreated to maximize refugia for non-target arthropods while 

simultaneously inducing target Orthoptera mortality at desired levels. RAATs are also described 

in detail in the final EIS that is incorporated by reference in the EA.

Comment 92

APHIS received the following comment, “It is unclear whether RAATs will even be used and 

how they will be used in the site specific area”.

APHIS’ preferred method of treatment is to use RAATs as a means to reduce program costs and 

potential environmental effects. However the program could decide to apply insecticides at 

conventional rates and total area coverage if a damaging grasshopper infestation warrants that 

level of suppression. These instances are rare due to monitoring and other technical assistance 

provided by APHIS. An explanation of the uncertainties involved with predicting grasshopper 

populations before they emerge is provided in section I.C. About this Process.

Comment 93

APHIS received the following comment, “APHIS could use the pesticide at 95% of the labelled 

rate and still call the application a RAAT.”

RAAT’s is defined as Reduced Agent and/or Area Treatments. The current pesticide labels for 

use in the Program do not allow applications at 95% of the labeled rate to be called RAATs.

This information was also summarized in the final EIS. EPA has approved the RAAT verbiage 

for each pesticide label. The labels clearly state which rates are allowed to meet a RAAT rate. In 

the case of Dimilin 2L label, which clearly states the application rates for RAAT’s is 0.75 - 1 

ounce per acre. “Use on rangeland only, in a RAAT’s application on early instars. A RAAT’s 

application is an IPM strategy that takes advantage of grasshopper movement and conservation 

biological control to allow Dimilin 2L to be applied on rangeland on a reduced treated area and 

at reduced rates, while sustaining acceptable control.”

The applicator can only use the RAAT’s rate of .75 or 1 ounce per acre. The label rate, if not 

using RAAT’s is 2 ounces/acre. The RAAT’s rate would be 50% of the label rate not 95% of 

labeled rate. 

In the case of using Carbaryl 5% bait the label rate is 20-40 lbs. per acre. APHIS uses the 

RAAT’s rate of 10lbs/acre. In the case of Carbaryl 2% bait, the label clearly states for ground 

applications 25 pounds/acre. It clearly states for U.S. Federal Government and State affiliated

Grasshopper/Mormon Cricket Suppression Programs using aerial applications the rate of 
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application is 10 pounds/acre. So clearly the RAAT’s applications are 50% or less than the 

labeled rates.

In the case of a full coverage treatment, the total acreage is treated. In the case of reduced area 

portion of RAAT’s the treatment area would be 50% less than a full coverage treatment. The 

reduced area is achieved through alternating the treated and untreated swath widths. The 

RAAT’s application rates are described in detail in the Draft EA’s and depending on the 

pesticide used in a treatment, the label will also specify or clarify what the RAAT’s rate. The 

reduced area is achieved by skipping a treated swath. For example, if the swath width of the 

treatment equipment is 40 feet, then the treated swath would be 40 feet. Then the adjacent swath 

would be skipped or untreated. The next treated swath would then be applied. So across the 

treatment block would be treated and untreated swaths. Thus the reduced area of actual treated 

ground, instead of a conventional broadcast treatment.

The RAAT procedures used by the program are flexible to allow for a reduction of pesticide use. 

Typically the RAAT procedures will result in half the amount of pesticide being applied to a 

treatment block than conventional rates and total coverage. Program managers may reduce the 

rate at which the pesticide is sprayed from the aircraft or increase the distance between swaths 

that are sprayed based on factors specific to grasshopper populations being suppressed. It 

should be noted that APHIS average RAAT rates are lower than the labeled RAAT rates further 

reducing pesticide loading into the environment.

Comment 94

APHIS received the following comment, “The agency must give the public a more precise 

definition of when the threshold for spraying has been met (i.e. number of grasshoppers or 

crickets/acre and a full description of the economic interests at stake).”

APHIS utilizes and provides links to extensive resources for determining when a grasshopper 

outbreak is exceeding economic thresholds including, “a level of economic infestation”. The 

Purpose and Needs section of the EA and supporting documents adequately define the multiple 

factors that must be evaluated before APHIS decides a treatment is necessary. Establishing a 

treatment threshold based on the number of grasshoppers ignores a variety of factors that must 

be considered by program managers before treatments. Some examples include how voracious 

the individual species are that compose a grasshopper infestation and the hardiness of 

rangeland vegetation within a proposed treatment block. These factors are also discussed in the 

recently published final EIS and are incorporated by reference in the final EA.

Comment 95

APHIS received the following comment, “APHIS must also convey what metrics will be used to 

determine the area that will be sprayed in any given outbreak”.

The size and exact configuration of a treatment block cannot be forecast prior to the emergence 

of the grasshoppers, requests from land managers and other cooperators, and other 

environmental considerations such as buffers from water and sensitive species. The program 

procedures and mitigation measures are adequately described in the EA and supporting 

documents.
85

APHIS is unable to predict exactly what areas will be treated before conducting surveys and 

completing the EA. For ground applications, the terrain is key to be able to treat safely. If the 

terrain is too rough to safely drive a UTV, then the area is not treated even though other factors 

warrant a treatment. There are many variables taken into account before an area is treated.

Another factor that must be considered is the movement of populations. If for any number of 

reasons, a treatment can be delayed there is a risk that, depending on species, the boundaries 

will have to be readjusted to account for the movement of populations.

For example, it is documented that Melanoplus sanguinipes, the Migratory Grasshopper can 

swarm and fly up to 5-10 miles normally. The longest migrations recorded in 1938 were made by 

swarms that traveled from northeastern South Dakota to the southwestern corner of 

Saskatchewan, a distance of 575 miles (Pfadt, 1994). This is why it is critical to have a rapid 

response to outbreaks. Population dynamics of grasshoppers and Mormon crickets are fluid and 

responses have to be adaptable to the most current assessments to ensure successful suppression 

treatments while minimizing environmental impacts.

Comment 96

APHIS received the following comment, “The agency must accurately and comprehensively 

disclose and analyze the range of rare, sensitive, threatened, and endangered species, ecological 

areas, communities, Native American gathering grounds and sensitive receptors that could 

potentially be significantly affected by the proposed project” Without this baseline data the EA 

cannot disclose the environmental effects of the project”.

In New Mexico, Native American gatherings are considered by some Tribes as Holy 

Ground and is only made available to APHIS when necessary. This will not be published or 

disclosed to the public as per Local Tribal Agreements. It is addressed in general terms when 

published in the EA. The more specific details are addressed with each individual Tribal Nation 

during the Tribal meetings. T&E species are analyzed during the FWS Section 7 

consultations. APHIS adheres to protective measures which have been agreed upon with FWS 

and addressed in the letters of concurrence. APHIS also works with Federal and State land 

managing agencies to protect other sensitive resources managed on their lands.

APHIS adequately summarized available data for current baseline conditions in the draft 

EA. This includes cultural resources as well as the potential for any overlap of federally listed 

species with the proposed areas of treatment.

Comment 97

APHIS received the following comment, “APHIS’s description of the environmental effects of 

the pesticides at issue failed to properly capture many of their environmental effects”.

APHIS prepared and published separate Final Human Health and Ecological Risk Assessments 

for all the pesticides used by the Grasshopper Programs (November 2019). These documents and 

the associated final EIS are incorporated by reference.
86

Comment 98

APHIS received the following comment, “Long-term exposure to carbaryl is associated with 

decreased egg production and fertility in birds”.

APHIS would make a single application per year to a treatment area, and could apply 

insecticide at an APHIS rate conventionally used for grasshopper suppression treatments, or 

more typically as reduced agent area treatments (RAATs). Carbaryl has a reported half-life on 

vegetation of three to ten days, therefore, long-term exposure to birds is not anticipated.

The study cited by the commenter noted. Carbaryl is practically nontoxic to birds on both an 

acute oral exposure (LD50 >2,000 mg/kg) and subacute dietary exposure basis (LC50 >5,000 

mg/kg of diet). In addition, no chronic effects were observed at a dietary exposure of 300 mg/kg 

of diet.

Comment 99

APHIS received the following comment, “Carbaryl is considered moderately toxic to mammals 

with decreased pup survival being the most sensitive effect”.

APHIS would make a single application per year to a treatment area, and could apply 

insecticide at an APHIS rate conventionally used for grasshopper suppression treatments, or 

more typically as reduced agent area treatments (RAATs). Carbaryl has a reported half-life on 

vegetation of three to ten days, therefore the chronic exposure to mammals that resulted in 

decreased pup survival is not anticipated.

Comment 100

APHIS received the following comment, “EPA has designated carbaryl as “highly toxic” to bees 

on a short-term exposure basis and ranged from moderately to highly toxic to other insects, mites 

and spiders”.

Although the Grasshopper Program has used the liquid formulation of carbaryl in the past, 

nearly all carbaryl applications this year and for the foreseeable future are likely to be a bait. 

The potential exposures of bees and other pollinators to carbaryl bait are minimal. The risks of 

carbaryl to bees and other non-target organisms are summarized in the human health and 

ecological risk assessment that was prepared to support the final EIS. This analysis is 

incorporated by reference into the final EA. At this time, carbaryl bait is not registered in New 

Mexico.

Comment 101

APHIS received the following comment, “Carbaryl is considered “highly toxic” to certain 

species of fish when exposed to short-term bursts and can reduce the number of eggs spawned 

when fish are exposed to lower levels over a longer period of time”.

The EA provided links to APHIS’ Grasshopper Program webpage where the 2019 EIS and Final 

Human Health and Ecological Risk Assessment for Carbaryl Rangeland Grasshopper and 

Mormon Cricket Suppression Applications are published. Comparison of the distribution of 

acute, sublethal and chronic effects data for fish to the residues estimated using ground and 
87

aerial ultra-low volume spray and bait applications show that the range of residues do not 

overlap with acute toxicity values, suggesting there is no acute risk to fish species. APHIS 

determined there is some overlap with chronic and sublethal effect values and estimated 

residues. However, carbaryl half-lives in water are typically short and with the proposed one 

time application chronic exposure and risk to fish is not anticipated. Effects from consumption of 

contaminated prey are also not expected to be a significant pathway of exposure, based on the 

low residues and low bioconcentration factor values reported for carbaryl. New Mexico will not 

treat riparian areas and buffer out all bodies of water.

Comment 102

APHIS received the following comments, “Carbaryl has been designated “very highly toxic” to 

aquatic invertebrates on an acute exposure basis by the EPA and mesocosm studies that analyze 

how the pesticide affects aquatic community structure have found significant negative effects at 

low levels”.

The EA provided links to APHIS’ Grasshopper Program webpage where the 2019 EIS and Final 

Human Health and Ecological Risk Assessment for Carbaryl Rangeland Grasshopper and 

Mormon Cricket Suppression Applications are published. The risk assessment summarizes the 

available laboratory and field effects data for aquatic invertebrates and carbaryl. The risk 

assessment also summarized the potential exposure and risk to aquatic invertebrates. The EIS 

and carbaryl risk assessment are incorporated by reference into the EAs. New Mexico will not 

treat riparian areas and buffer out all bodies of water.

Comment 103

APHIS received the following comment, “The EPA identified potential interactions between 

carbaryl and the androgen pathway in fish, indicating that carbaryl is an endocrine disruptor in 

male aquatic vertebrates”.

Carbaryl half-lives in water are typically short and with the proposed one time application 

chronic exposure and endocrine disruption risk to fish is not anticipated. Effects from 

consumption of contaminated prey are also not expected to be a significant pathway of exposure, 

based on the low residues and low bioconcentration factor values reported for carbaryl. Chronic 

risk is also a conservative estimate because chronic toxicity data is based on long-term 

exposures that what would not be expected to occur from a single application, based on the 

environmental fate of carbaryl in aquatic environments. The final EIS and human health and 

ecological risk assessment for carbaryl provides additional information regarding the 

effects of carbaryl to fish. New Mexico will not treat riparian areas and buffer out all bodies of 

water.

Comment 104

APHIS received the following comment, “On March 12, 2020, the EPA released a draft 

biological opinion finding that carbaryl is likely to adversely affect 1542 out of 1745, or 86% 

percent of all listed species in the U.S. and 713 out of 776 designated critical species’ habitats 

across the U.S.”.
88

The Endangered Species Act section 7 pesticide consultation process between the U.S. Fish and 

Wildlife Service and the National Marine Fisheries Service (the Services, collectively) and the 

EPA specifically concerns FIFRA pesticide registration and reregistration in the United States, 

including all registered uses of a pesticide. The state-level Biological Assessments for APHIS 

invasive species programs are separate from any consultations conducted in association with 

pesticide registration and reregistration process.

The Agricultural Improvement Act of 2018 (Farm Bill) created a partnership between USDA, 

EPA, the Services, and the Council on Environmental Quality to improve the consultation 

process for pesticide registration and reregistration. USDA is committed to working to ensure 

consultations are conducted in a timely, transparent manner and based on the best available 

science. The Revised Method for National Level Listed Species Biological Evaluations of 

Conventional Pesticides provides a directionally improved path to ensuring that pesticides can 

continue to be used safely for agricultural production with minimal impacts to threatened and 

endangered species.

APHIS provided information about use of carbaryl to EPA for the FIFRA consultation for 

carbaryl. The Grasshopper Program use of carbaryl has in the past comprised substantially less 

than 1% of the percent crop treated (PCT) for rangeland use of carbaryl. This is the case for the 

reasonably foreseeable future. For rangeland, in the EPA BE, the Grasshopper Program’s very 

low usage was rounded up to <1% PCT, which gives an overestimate of rangeland acres treated 

and thus endangered species risk. APHIS use of carbaryl is even smaller compared to all uses of 

carbaryl nationwide. Further, the Grasshopper Program consults directly with the Services to 

ensure program activities do not adversely affect protected species or their critical habitat.

Comment 105

APHIS received the following comment, “EPA found many New Mexico species were likely to 

be adversely affected. This is a chemical far too toxic for APHIS to consider using across wide 

swaths of land in New Mexico.”

Carbaryl is presently approved by the EPA and registered in New Mexico. The APHIS proposed 

use for carbaryl in New Mexico is not proposed for use across wide swaths of New Mexico but in 

Limited areas that require a suppression treatment. It should be noted that the current labeled 

uses for carbaryl grasshopper treatments are at much higher rates and can be applied with more 

frequency than what APHIS is proposing for use in New Mexico. In addition carbaryl use by the 

Program is minor compared to the preferred alternative diflubenzuron. APHIS has evaluated 

the risk of carbaryl use in the Program and in general the conclusions are consistent with other 

risk assessments demonstrating low risk when adhering to label requirements. Additional 

mitigation measures used by APHIS further reduces the risk to human health and the 

environment.

As stated in the final EIS, APHIS has completed programmatic consultation with the National 

Marine Fisheries Service (NMFS). APHIS has reinitiated programmatic consultation with 

NMFS to include chlorantraniliprole. In the interim, APHIS will consult with NMFS at the State 

level if there is a proposal to apply chlorantraniliprole. The NMFS consultation does not apply 

to species in Arizona since there are no federally listed species under NMFS jurisdiction 
89

however the information was provided in response to comments regarding the final EIS. APHIS 

submitted a programmatic biological assessment to the FWS in 2015. APHIS is currently 

working with the FWS to update and complete the biological assessment and receive 

concurrence. The intent of the programmatic biological assessment is to provide consistent 

mitigation measures for listed species that may co-occur with Program treatments. Consultation 

with the FWS is still being completed at the local level prior to any treatments. No APHIS 

treatments are made in States without prior concurrence from the FWS or NMFS regarding 

federally-listed species. This information is also summarized in the final EIS.

APHIS consulted with the FWS on federally-listed species that may occur within the county or 

areas where grasshopper and Mormon cricket treatments may be required. APHIS works 

closely with the FWS to determine the application of protection measures and where those 

measures should be applied prior to any treatments. APHIS also evaluated the potential direct 

and indirect impacts to non-target species which is summarized in the final human health and 

ecological risk assessments for each insecticide. 

Comment 106

APHIS received the following comment, “The European Union banned carbaryl in 2007 due to, 

among other things, “...a high long-term risk for insectivorous birds and a high acute risk to 

herbivorous mammals, a high acute and long-term risk to aquatic organisms and a high risk for 

beneficial arthropods”.

APHIS summarizes the risk of carbaryl to non-target organisms in final human health and 

ecological risk assessment that was part of the recently published final EIS. Available effects 

data and the exposures that would be expected from proposed use in the grasshopper and 

Mormon cricket program are reduced based on mitigation measures (ex. RAATS, aquatic 

buffers) application methods and formulation types which further reduce risk.

Comment 107

APHIS received the following comments, “Carbaryl is classified as “likely to be carcinogenic to 

humans” based on treatment-related hemangiosarcoma development in mice”.

The levels of carbaryl that caused the above-mentioned effects to mice are above exposure 

concentrations that would be expected to occur for the public as well as workers and applicators 

in the APHIS grasshopper and Mormon cricket suppression program. The risk to human health 

from carbaryl use, including the proposed APHIS use, have been evaluated by APHIS and are 

discussed in the final human health and ecological risk assessment for carbaryl. It should be 

noted that other agencies have evaluated the risk to carbaryl at much higher application rates 

than those used in the grasshopper and Mormon cricket program.

Comment 108

APHIS received the following comments, “EPA has determined that humans can be exposed to 

more than 4 times the amount of carbaryl known to cause neurotoxicity from some legal uses of 

the pesticide. EPA also found that the current labelled uses of carbaryl may result in neurotoxic 

harms to mixers, loaders and applicators.”
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The EA provided links to APHIS’ Grasshopper Program webpage where the 2019 EIS and Final 

Human Health and Ecological Risk Assessment for Carbaryl Rangeland Grasshopper and 

Mormon Cricket Suppression Applications are published. APHIS evaluated the potential human 

health risks from the proposed use of carbaryl ULV sprays and carbaryl bait applications and 

determined that the risks to human health are low. The lack of risk to human health is based on 

the low probability of human exposure and the favorable environmental fate and effects data.

APHIS treatments are conducted in rural rangeland areas where agriculture is a primary 

economic factor. Rural rangeland areas consist of widely scattered, single dwellings in ranching 

communities with low population density. Risk to the general public from carbaryl ground or 

aerial applications is also expected to be minimal due to the low-population areas proposed for 

treatment, adherence to label requirements, and additional Program measures designed to 

reduce exposure to the public. APHIS is not obligated to analyze the risk posed by all legal uses 

of carbaryl, but rather the Grasshopper Program formulations and application rates.

The proposed use of carbaryl as a ULV spray, or a bait, and adherence to label requirements 

substantially reduces the potential for exposure to humans. APHIS does not expect adverse 

health risks to workers because of the low potential for exposure to carbaryl when applied 

according to label directions and use of personal protective equipment. APHIS quantified the 

potential risks associated with accidental exposure of carbaryl for workers during mixing, 

loading, and application. The quantitative risk evaluation results indicate no concerns for 

adverse health risk for Program workers from carbaryl applications in accordance with 

program standard operating procedures for safety.

Comment 109

APHIS received the following comment, “EPA has found that all use scenarios 

of chlorantraniliprole can result in direct or indirect effects to all listed species”.

The EPA risk assessment is a screening level ecological risk assessment that evaluated risk 

under a variety of application rates with most being well above use rates proposed in the APHIS 

Grasshopper Program. APHIS prepared a final human health and ecological risk assessment 

that assesses the risk of APHIS Program treatments. The state-level Biological Assessments for 

APHIS invasive species programs are separate from any consultations conducted in association 

with pesticide registration and reregistration process.

As previously stated, the Grasshopper Program will not be using chlorantraniliprole in New 

Mexico during 2020. Therefore any chlorantraniliprole exposure scenarios which the 

commenter is concerned about are not relevant at this time.

Comment 110

APHIS received the following comment, “EPA has found that all use scenarios 

of chlorantraniliprole can result in direct or indirect effects to all listed species. 

Chlorantraniliprole is considered “very highly toxic” to freshwater invertebrates and EPA found 

that many uses of it can result in acute and chronic harms to aquatic invertebrates. This was the 

case for both aerial and ground spray applications. Sublethal doses can impair locomotion in 

bees more than seven days post exposure. A 2013 European Food Safety Authority analysis 
91

of chlorantraniliprople found that the use of the pesticide poses a high risk to soil macroorganisms, aquatic invertebrates and sediment dwelling organisms.” and “APHIS must 

consider chlorantraniliprole substantial environmental impacts, including population level 

effects”.

The EA provided links to APHIS’ Grasshopper Program webpage where the 2019 EIS and Final 

Human Health and Ecological Risk Assessment for Chlorantraniliprole Rangeland Grasshopper 

and Mormon Cricket Suppression Applications is published. The document summarizes 

available effects data and characterizes risk to human health and non-target organisms based on 

the use pattern proposed by the Program. Results from the risk assessment suggest low risk 

of chlorantraniliprole to non-target aquatic organisms and most terrestrial invertebrates.

As previously stated, the Grasshopper Program will not be using chlorantraniliprole in New 

Mexico during 2020. Therefore any chlorantraniliprole exposure scenarios which the 

commenter is concerned about are not relevant at this time.

Comment 111

APHIS received the following comments, “Diflubenzuron is considered “highly” to “very highly 

toxic” to aquatic invertebrates. In a 2018 analysis, EPA found that the registered, labeled uses of 

diflubenzuron may result in freshwater invertebrate exposure at up to 550 times the level known 

to cause harm. Diflubenzuron exposure to honeybees and other pollinators at the larval stage was 

estimated to be more than 500 times the level known to cause harm. Although arthropods are not 

a part of EPA’s ecological risk assessment, the European Food Safety Authority found that 

“Juvenile non-target arthropods were very sensitive to diflubenzuron. Very large in-field nospray buffer zones would be needed to protect nontarget arthropods. There is no reason for 

APHIS to exclude consideration of impacts to arthropods in its analysis of this pesticide.” 

The EA provided links to APHIS’ Grasshopper Program webpage where the 2019 EIS and Final 

Human Health and Ecological Risk Assessment for Diflubenzuron Rangeland Grasshopper and 

Mormon Cricket Suppression Applications are published. The EPA risk assessment evaluated 

risk to aquatic organisms and pollinators based on application rates, methods of application and 

use patterns that would result in greater exposure and risk to aquatic and terrestrial 

invertebrates. APHIS evaluated risks to these groups of non-target organisms based on methods 

of application consistent with Program applications and other mitigation measures for 

diflubenzuron. The exposure potential is reduced compared to label uses due to many factors.

This includes but is not limited to reduced application rates, one application per season, use of 

RAATs and buffers from aquatic habitats. APHIS relied on laboratory and field collected data 

regarding diflubenzuron effects to aquatic and terrestrial invertebrates to show that risk is low 

for most non-target invertebrates. 

Characterization of risk to aquatic species from Program-specific diflubenzuron applications 

was made by comparing the residue values in the exposure analysis from ground and aerial 

applications to the distribution of available acute and chronic fish toxicity data. Residue values 

were below the distribution of acute and chronic response data, suggesting that direct risk to 

aquatic species is not expected from diflubenzuron applications. More specifically, the 
92

distribution of aquatic invertebrate toxicity data is above the residues estimated from spray drift 

models for Grasshopper Program ground and aerial applications of diflubenzuron.

The Endangered Species Act section 7 pesticide consultation process between the U.S. Fish and 

Wildlife Service and the National Marine Fisheries Service (the Services, collectively) and the 

EPA specifically concerns FIFRA pesticide registration and reregistration in the United States, 

including all registered uses of a pesticide. The Grasshopper Program treatments employ 

methods and diflubenzuron application rates that result in substantially lower freshwater 

invertebrate exposures than the rate cited by the EPA and the commenter.

The EPA Preliminary Risk Assessment to Support Re-registration Review examines all legal uses 

of diflubenzuron, of which the Grasshopper Program constitutes a small fraction. APHIS is not 

obligated to examine all legal uses of the pesticide, but rather those contemplated by the 

program. The EA provided links to APHIS’ Grasshopper Program webpage where the 2019 EIS 

and Final Human Health and Ecological Risk Assessment for Diflubenzuron Rangeland 

Grasshopper and Mormon Cricket Suppression Applications are published. Characterization of 

risk to aquatic species from diflubenzuron applications was made by comparing the residue 

values in the exposure analysis from ground and aerial applications to the distribution of 

available acute and chronic fish toxicity data. Residue values were below the distribution of 

acute and chronic response data, suggesting that direct risk to aquatic species is not expected 

from diflubenzuron applications. More specifically, the distribution of aquatic invertebrate 

toxicity data is above the residues estimated from spray drift models for Grasshopper Program 

ground and aerial applications of diflubenzuron.

The EA provided links to APHIS’ Grasshopper Program webpage where the 2019 EIS and Final 

Human Health and Ecological Risk Assessment for Diflubenzuron Rangeland Grasshopper and 

Mormon Cricket Suppression Applications are published. The APHIS analysis noted 

Diflubenzuron has low toxicity and risk to some nontarget terrestrial invertebrates, including 

pollinators such as honey bees.

Comment 112

APHIS received the following comment, “APHIS also acknowledges the pollinator impacts but 

attempts to diminish them without providing evidence on how or why they are not significant. 

It does not mention that New Mexico is home to an amazing abundance of native bees and 

pollinators, and improperly uses honeybees as a surrogate for pollinators, when native pollinators 

are far more sensitive due to the lack of hive buffering effects. This is not a pesticide that should 

be applied to broad swaths of land. It is highly toxic to far too many species of importance in 

New Mexico.”

See previous response. 

Grasshopper IPM field studies have shown diflubenzuron to have a minimal impact on ants, 

spiders, predatory beetles, and scavenger beetles. There was no significant reduction in 

populations of these species from 7 to 76 days after treatment. Although ant populations 

exhibited declines of up to 50%, these reductions were temporary, and population recovery was 

described as immediate (Catangui et al., 1996). No significant reductions in flying non-target 

arthropods, including honey bees, were reported. Within one year of diflubenzuron applications 
93

in a rangeland environment, no significant reductions of bee predators, parasites, or pollinators 

were observed for any level of diflubenzuron treatment (Catangui et al., 1996).

Comment 113

APHIS received the following comment, “Diflubenzuron is present in the excreted manure and 

urine of cattle where they range and the cumulative exposure must be considered in accordance 

with the ESA and NEPA’s mandate that an action agency take into account the environmental 

baseline”.

APHIS recognizes that some diflubenzuron resides may be present in urine and feces from cattle 

that feed on forage immediately after diflubenzuron treatment; however this pathway of 

exposure is expected to be minor based on the proposed use pattern of diflubenzuron in the 

Program. Low application rates applied only once per season will reduce the amount of 

diflubenzuron present in manure and urine. In addition some metabolism of 

diflubenzuron occurs in animals, and there will be further environmental degradation once 

excreted. 

Comment 114

APHIS received the following comment, “Malathion is considered “very highly toxic” to all 

aquatic and terrestrial invertebrates, as well as aquatic vertebrates such as fish. In addition 

indirect effects to taxa should be considered.”

The EA provided links to APHIS’ Grasshopper Program webpage where the 2019 EIS and Final 

Human Health and Ecological Risk Assessment for Malathion Rangeland Grasshopper and 

Mormon Cricket Suppression Applications are published. The risk assessment summarizes 

available laboratory and field collected aquatic and terrestrial effects data for malathion and 

then estimated risk based on conservative estimates of exposure. APHIS recognizes in the risk 

assessment that malathion can be toxic to sensitive non-target species however the effects have 

to be considered in relation to the potential for exposure to estimate risk, as well as historical 

use in the Program which is negligible. 

New Mexico is very unlikely to use malathion and then only as a last resort. New Mexico also 

will not treat riparian areas or bodies of water.

Comment 115

APHIS received the following comment, “When exposed to malathion for longer periods of 

time, female birds displayed regressed ovaries, reduced number of hatched eggs and enlarged 

gizzards”.

The EA provided links to APHIS’ Grasshopper Program webpage where the 2019 EIS and Final 

Human Health and Ecological Risk Assessment for Malathion Rangeland Grasshopper and 

Mormon Cricket Suppression Applications are published.

Several reproductive and developmental studies have been conducted with birds. The lowest 

median lethal dose to chicken embryos (eggs) was 3.99 mg per egg for 4-day embryos 

(Greenberg and LaHam, 1969). The median lethal concentration for field applications of 
94

malathion to mallard duck eggs was found to be 4.7 lbs. a.i./acre (Hoffman and Eastin, 1981). 

This is approximately five times greater than the maximum rate for rangeland grasshopper 

(0.928 lbs. a.i./acre), 7.6 times greater than the maximum APHIS application rate 

(0.619 lbs. a.i./acre), and nearly 19 times greater than the average RAATs rate applied by 

APHIS.

No effect on reproductive capacity of chickens was found at dietary concentrations as high as 

500 ppm in feed (Lillie, 1973). Based on the results from chronic reproduction studies using the 

bobwhite quail and mallard duck, the NOEC values were 110 and 1,200 ppm, respectively. The 

most sensitive endpoint in the quail study was regressed ovaries and reduced egg hatch at the 

next highest test concentration (350 ppm). The effect endpoint in the mallard study was growth 

and egg viability at the 2,400 ppm level Lowest Observed Effect Concentration (LOEC).

APHIS expects that direct avian chronic effects would be minimal for most species. The 

preferred use of RAATs during application reduces these risks by reducing residues on treated 

food items and reducing the probability that they will only feed on contaminated food items. In 

addition, malathion degrades quickly in the environment and residues on food items are not 

expected to persist.

As previously stated, New Mexico is very unlikely to use malathion and then only as a last 

resort.

Comment 116

APHIS received the following comments, “Malathion degrades into malaoxon, which has been 

shown to be at least 22 times more toxic than the parent molecule”.

Similar to other organophosphate pesticides, malathion inhibits the enzyme AChE in the central 

and/or peripheral nervous system. Malathion is metabolized to malaoxon, which is the 

active AChE inhibiting metabolite. AChE inhibition is through phosphorylation of the serine 

residue at the active site of the enzyme, and leads to accumulation of acetylcholine and 

ultimately neurotoxicity. Malaoxon goes through detoxification with subsequent metabolism. 

Absorption and distribution of malathion and malaoxon are rapid with extensive metabolism and 

no accumulation in tissues.

Carboxylesterase detoxifies malathion and malaoxon to polar and water-soluble compounds for 

excretion. A rat metabolism study showed 80 to 90% of malathion excretion in the urine in the 

first 24 hours of exposure. Mammals are less sensitive to the effects of malathion than insects 

due to greater carboxylesterase activity resulting in less accumulation of malaoxon.

Available aquatic toxicity data show that malaoxon is approximately 1.5 to 6 times more toxic to 

fish and 1.8 to 93 times more toxic to amphibians. FMC, in their 2019 public response to 

the Grasshopper Program EIS, reported that malaoxon is 0.80 to 2.58 times more toxic to fish 

than malathion based on data that were determined to meet their criteria for 

acceptability (FMC, 2014). The conversion of malathion to malaoxon in aquatic environments 

can range from approximately 1.8 to 10% (CDPR, 1993; Bavcon et al., 2005; USEPA, 2012).
95

While APHIS assumed that malaoxon is most likely more toxic to aquatic invertebrates than the 

parent; however, due to its low percentage of occurrence in aquatic systems and its rapid 

breakdown, malaoxon is not anticipated to pose a greater aquatic risk when compared to 

malathion.

As previously stated, New Mexico is very unlikely to use malathion and then only as a last 

resort.

Comment 117

APHIS received the following comment, “A 2017 EPA biological evaluation also found that the 

use of malathion is likely to adversely affect 1778 out of 1835 listed species in the U.S. and 784 

out of 794 critical species’ habitats across the U.S. These findings were based on methodology 

recommended by the National Academy of Sciences. EPA found many New Mexico species 

were likely to be adversely affected, such as the yellow billed cuckoo. The U.S. Fish and 

Wildlife Service later drafted a biological opinion finding that malathion is likely to jeopardize 

the continued existence of 1284 threatened and endangered species. This is an astounding 

number of jeopardy calls for a single pesticide, and makes it even more astounding that APHIS 

would continue to consider using it for grasshopper and cricket control.”

The Endangered Species Act section 7 pesticide consultation process between EPA and the 

Services specifically concerns FIFRA pesticide registration and reregistration in the United 

States, including all registered uses of the pesticide. The Grasshopper Program’s use of 

malathion comprised nearly none of the percent crop treated for rangeland in the past, and this 

remains APHIS’ expectation for the foreseeable future. Further, the Grasshopper Program 

consults directly with the Services to ensure program activities do not adversely affect protected 

species or their critical habitat.

As previously stated, New Mexico is very unlikely to use malathion and then only as a last 

resort.

Comment 118

APHIS received the following comment, “California’s Proposition 65 list of chemicals known to 

cause cancer and has been designated as having suggestive evidence of carcinogenicity by the 

EPA for instances of liver, oral palate mucosa and nasal respiratory epithelium tumor formation 

in mice.”

The EA provided links to APHIS’ Grasshopper Program webpage where the 2019 EIS and Final 

Human Health and Ecological Risk Assessment for Malathion Rangeland Grasshopper and 

Mormon Cricket Suppression Applications are published

As previously stated, New Mexico is very unlikely to use malathion and then only as a last 

resort.

Comment 119

APHIS received a comment that, “EPA has determined that humans can be exposed to more than 

6 times the amount of malathion known to cause neurotoxicity from some legal uses of the 
96

pesticide. EPA also found that the current labelled uses of malathion may result in neurotoxic 

harms to those exposed to pesticide drift from aerial applications at labelled rates”. The 

commenter also pointed out that occupational applicators, mixers and loaders can be exposed to 

malathion through inhalation and dermal absorption at levels above what the EPA considers safe 

– even when using required personal protective equipment.”

APHIS evaluated the risk to human health, including neurotoxicity data in its finale human 

health and ecological risk assessment. The risk assessment was prepared based on APHIS use 

patterns and Program mitigations that reduce risk to human health. APHIS is not obligated to 

ensure the EA and supporting documents analyze the risk posed by all legal uses of malathion, 

but rather the Grasshopper Program methods and application rates.

Malathion exposure to the general public is not expected from the program use based on label 

requirements and program standard operating procedures that prevent potential exposure. Only 

protected handlers may be in the area during application, and entry of the general public into 

the treated area is not allowed during the re-entry interval period. APHIS treatments are 

conducted on rural rangelands, where agriculture is a primary economic factor and widely 

scattered dwellings in low population density ranching communities are found. The program 

requires pilots avoiding flights over congested areas, water bodies, and other sensitive areas. 

Aerial applications are not allowed while school buses are operating in the treatment area; 

within 500 feet of schools or recreational facilities; when wind velocity exceeds 10 miles per 

hour (mph) (unless a lower wind speed is required under State law); when air turbulence could 

seriously affect the normal spray pattern; and/or temperature inversions could lead to off-site 

movement of spray. The Grasshopper Program also notifies residents within treatment areas, or 

their designated representatives, prior to application to reduce the potential for incidental 

exposure.

APHIS acknowledges workers in the program are the most likely human population segment to 

be exposed to malathion during grasshopper treatments. Occupational exposure to malathion 

may occur through inhalation and dermal contact during ground and aerial applications. Direct 

contact exposure from the application of a malathion ULV spray will be minimal with adherence 

to label requirements, the use of personal protective equipment (PPE), general safety hygiene 

practices, and restricted entry intervals into treated areas after application. EPA estimates of 

risk to workers is based on use patterns and rates that result in greater exposure to malathion 

than would occur in the APHIS program. APHIS evaluated the risk from program specific uses 

of malathion and demonstrated low risk to applicators. It should also be noted that historical 

malathion use in the Program is negligible further reducing the potential for any types of human 

health risk.

As previously stated, New Mexico is very unlikely to use malathion and then only as a last 

resort.

Comment 120

APHIS received the following comment, “APHIS touts EPA-approval as an indication that the 

pesticides that the agency proposes to use are safe. However, under our nation’s pesticide laws, 
97

EPA-approval is an indication that use of the pesticide won the agency’s cost-benefit analysis, 

and should not be misconstrued as a finding of safety.”

The EA provided links to APHIS’ Grasshopper Program webpage where the 2019 EIS 

and human health and ecological risk assessments for pesticides used by the 

Grasshopper Program are published. APHIS does not assert the FIFRA registration of the 

pesticides by the EPA demonstrates that the Grasshopper Program uses are safe. Instead the 

extensive risk analysis published by APHIS considered whether the suppression of grasshopper 

population will have significant environmental impacts, in accordance with NEPA.

Comment 121

APHIS received the following comment, “APHIS does not discuss or account for how pesticides 

impact overall soil health or the health of any organisms that reside in soil.”

The EA provided links to APHIS’ Grasshopper Program webpage where the 2019 EIS and 

HHERA for pesticides used by the Grasshopper Program are published. The HHERA contain 

extensive analysis of pesticide effects on terrestrial vertebrates, many of which reside in soil.

Comment 122

APHIS received the following comment, “Impacts on soil health can impact listed and non-listed 

plants by impacting nutrient cycling, soil oxygenation and soil water retention, as well as listed 

and non-listed animals that rely on plants or soil organisms for their survival.”

The Grasshopper Program applies pesticides in accordance with current label restrictions 

and program operational procedures that are mitigations to minimize significant exposure of 

soil, water, and air to insecticides; grasshopper chemical treatments are not expected to persist 

or bioaccumulate in the environment. APHIS evaluated these effects in human health and 

ecological risk assessments that were prepared along with the final EIS for the grasshopper and 

Mormon cricket suppression program.

Comment 123

APHIS received the following comment, “Carbaryl was ranked as extremely toxic to earthworms 

in a lab test rating pesticide toxicity from relatively nontoxic, moderately toxic, very toxic, 

extremely toxic, and super toxic.”

The study was a comparison of the toxicology of 45 pesticide to determine the LC50. These 

studies exposed earthworms to varying concentrations of carbaryl to determine toxicological 

endpoints. Based on the extremely high doses, the impact to the survival of earthworms was not 

only unsurprising, but the object of the studies. APHIS would like to note this laboratory dosing 

procedure is not comparable to any exposure levels resulting from the use of carbaryl ultra-low 

volume sprays by the Grasshopper Program.

Comment 124

APHIS received the following comment, “A single application of carbaryl in a field study caused 

a 38% reduction in survival of total Lumbricidae, and a 78% reduction in total earthworms for at 

least 5 weeks.”
98

APHIS would like to note the “single application” involved applying carbaryl 6 times on a 

weekly interval to its assigned plots at the highest recommended dose (i.e. Sevin at 9.12 mg/m2), 

a rate that is greater than 16 times the Grasshopper ultra-low volume liquid rate (0.56 mg/m2). 

The Grasshopper program only makes one application per year, rather than six weekly 

treatments. Also, the field study found carbaryl significantly inhibited earthworm feeding activity

for at least three weeks without leading to any earthworm death.

In addition, the 78% reduction in earthworm casts noted in the comment resulted from an 

application of a combination of clothianidin and bifenthrin pesticides.

Comment 125

APHIS received the following comment, “Carbaryl significantly impacted the survival or 

population abundance of E. fetida, E. andrei, Lumbricus terrestris, 

and Lumbricus rubellus, Aporrectodea caliginosa, and Allolobophora chlorotica.”

These studies exposed earthworms to varying concentrations of carbaryl to determine 

toxicological endpoints (NOEC, LC50). Based on the extremely high doses, the impact to the 

survival of earthworms was not only unsurprising, but the object of the studies. For example in 

Lima et al. 2011, ten adult worms with individual fresh weight between 300 and 600 mg, were 

exposed to different carbaryl concentrations (20, 40, 60, 80, 100 mg/kg). APHIS would like to 

clarify the Grasshopper Program applies carbaryl ultra-low volume spray at a rate of half a 

pound active ingredient per acre.

Comparison of the results of paper contact test with those obtained in soils clearly demonstrates 

that the contact test has no predictive values for the toxicity of an insecticide in soils, though it is 

important for the initial screening of the environmental chemicals. The differences between 

lowest and highest LC50 values of insecticides for M. posthuma and E. fetida in paper contact 

method were only 6.9 and 2.5-fold respectively while in soil they were over 38 and 26-fold. 

These data demonstrated that worms could tolerate higher concentrations in soil than on moist 

filter paper. This difference in the behavior of the insecticide may probably due to the rate of 

diffusion/uptake of insecticide from the medium into the body of the earthworm. It is well 

reported in the literature that insecticides are adsorbed on soil medium through strong binding 

by organic matter contents in soils (Davis, 1971, Van Gestel and Van Dis, 1988). Hence, the 

availability of insecticide for diffusion will be less from the soil than the impregnated filter 

paper. Contact filter paper test can be used as an initial screening technique to assess the 

relative toxicity of chemicals; however it fails to represent the situation in the soil ecosystem. 

Artificial soil test is more representative of the natural environment of earthworms and acute 

toxicity data on several insecticides can be used in the ecological risk assessment on soil 

ecosystems.

Comment 126

APHIS received the following comment, “In another study, carbaryl induced an avoidance 

response in E. fetida. Soil structure changes were observed between the control and carbaryl 

treated sites, with higher treatments of carbaryl causing significantly more lumps in the soil due 

to earthworm inactivity.”
99

The commenter cited a study where worms were rinsed in tap water and transferred to the flasks 

containing 2 ml solution per worm. The flasks were gently tilted every 5 min and the exposure 

was terminated after 30 min. The worms were removed, rinsed in cold tap water and transferred 

to Petri dishes (five worms in each) containing soil but no pesticide. The worms were inspected 

at intervals during 80 days or until all the worms were dead or had recovered. The structure of 

the soil in the Petri dishes was observed in order to get an idea about the ability to work the soil 

after pesticide treatment. APHIS would like to note this laboratory dosing procedure is not 

comparable to any exposure scenario resulting from the use of carbaryl ultra-low volume sprays 

by the Grasshopper Program.

Notably, E. foetida could tolerate high concentrations of carbaryl without dying, although low 

concentrations severely affected its ability to work the soil or to disappear from the soil surface. 

The researchers believe the solutions were equivalent to 64, 32, 16, 8 and 4 mg/kg of pesticide, 

and found that carbaryl did not kill E. foetida in concentrations up to 64 mg/kg, from the 800 

mg/l solution.

The avoidance test is a behavioral test with several advantages (simple, quick and cheap) but 

one drawback: this is not a measure of toxicity but rather a measure of repellence 

(Capowiez and Bérard, 2006), and thus is termed ‘measure of habitat modification’. As there is 

not always a direct relationship between avoidance and toxicity, an improvement of this test was 

recently proposed by Sanchez-Hernandez (2006).

APHIS would like to clarify the Grasshopper Program applies carbaryl ultra-low volume spray 

at a rate of half a pound active ingredient per acre. If a cubic foot of rangeland soil weighs 75 

pounds, 1 acre (43,560 ft.2) of soil two inches deep would weigh 544,500 pounds, or 246,981 

kilograms. The maximum rate used by the Grasshopper Program to apply carbaryl as an ultralow volume spray is half a pound (226796 mg) active ingredient per acre. Therefore, the 

maximum concentration of 0.92 mg carbaryl spray per kg of soil could result from program 

applications. However, this analysis assumes none of the foliar spray settled on vegetation, 

and all of the carbaryl is instantaneously absorbed into the top two inches of soil. In addition, 

this maximum concentration was less than the lowest concentration which the researchers 

determined has significant effects on the reduction of the P. excavatus hatching rate (1.51 mg

carbaryl per kg of soil). 

Comment 127

APHIS received the following comment, “Carbaryl negatively affected the biomass 

of E. andrei, Perionyx excavates, total earthworms, and Lumbricus terrestris at a tenth of the 

recommended dose.”

The carbaryl concentrations used for each test species was chosen based on the LC50/EC50 

previously carried out and reported by Lima et al. (2011). This was also a toxicological endpoint 

study where the acute toxicity was determined by exposing the worms to a nominal concentration 

range of 20 to 100 mg/kg of technical grade carbaryl. The application rate was 850 grams per 

hectare of Sevin L85 which is equal to 1.12 pounds active ingredient carbaryl per acre, 
100

compared with Sevin XLR which is 44.1 % applied at half a pound active ingredient per acre by 

the Grasshopper Program.

This study was primarily designed to validate the production of casts by earthworms as a 

biomarker for behavioral effects. While the significant effects in earthworm weight observed at 

low concentrations of carbaryl are concerning, Grasshopper program applications of foliar 

sprays are unlikely to result in the subsurface soil becoming saturated at the concentrations 

created in the laboratory.

Comment 128

APHIS received the following comment, “A 60-99% reduction in earthworm biomass and 

density due to carbaryl treatment lasted 20 weeks. Burial of organic matter was also negatively 

affected. Casting activity of earthworms was reduced by 90%, and 71% and 81% after 3 and 5 

weeks, respectively.”

The researchers made two applications of carbaryl at a rate of 8 lbs. a.i./acre, 16 times greater 

than the maximum spray rate employed by the Grasshopper Program. The Grasshopper 

Program only makes one application per year. In addition, the foliar spray of ultra-low volume 

carbaryl over rangeland is unlikely to result in subsurface soil concentrations comparable to the 

direct turfgrass application made in this study.

Comment 129

APHIS received the following comment, “Carbaryl negatively affected growth in E. fetida, and 

the feeding rate of Diplocardia spp. Total cast production of L. terrestris was significantly 

impacted at one-tenth of the recommended field rate.”

The lowest test concentration that effected E. fetida resulted from saturation of the test media 

with 25 mg/kg of carbaryl. Another field study found a single application of carbaryl 

significantly inhibited earthworm (Diplocardia spp.) feeding activity for at least three 

weeks without leading to any earthworm death. APHIS would like to note the “single 

application” involved applying carbaryl 6 times on a weekly interval to its assigned plots at the 

highest recommended dose (i.e. Sevin at 9.12 mg/m2), a rate that is greater than 16 times the 

Grasshopper ultra-low volume liquid rate (0.5 lbs. a.i./acre). The Grasshopper program only 

makes one application per year, rather than six weekly treatments.

Comment 130

APHIS received the following comment, “Reproduction of E. fetida, 

and Perionyx excavatus was negatively affected, with the hatching rate of P. excavatus reduced 

by 87% at sublethal concentrations lower than the recommended field rate. A total loss of 

burrowing was observed at 4 and 8 mg/kg after 40 minutes and at 1 and 2 mg/kg after 80 

minutes.”

The lowest test concentration that effected E. fetida resulted from saturation of the test media 

with 25 mg/kg of carbaryl. In another study the reduction of the P. excavatus hatching rate was 

observed at a concentration of 1.51 mg carbaryl per kg of soil.
101

APHIS would like to clarify the Grasshopper Program applies carbaryl ultra-low volume spray 

at a rate of half a pound active ingredient per acre. If a cubic foot of rangeland soil weighs 75 

pounds, 1 acre (43,560 ft.2) of soil two inches deep would weigh 544,500 pounds, or 246,981 

kilograms. The maximum rate used by the Grasshopper Program to apply carbaryl as an ultralow volume spray is half a pound (226796 mg) active ingredient per acre. Therefore, the 

maximum concentration of 0.92 mg carbaryl spray per kg of soil could result from program 

applications (0.92 mg/kg). However, this analysis assumes none of the foliar spray settled on 

vegetation, and the carbaryl instantly absorbed into the top two inches of soil, thus mirroring the 

laboratory conditions. In addition, this maximum concentration was less than the lowest 

concentration which the researchers determined has significant effects on the reduction of the 

P. excavatus hatching rate (1.51 mg/kg).

Comment 131

APHIS received the following comment, “Morphological abnormalities and histological changes 

in E. andrei and M. posthuma were observed at very low, sublethal doses ranging from 0.24-1.20 

mg/kg and 0.5-1.20 mg/kg, respectively.”

The cited study did not test E. andrei but rather E. fetida a closely related species. The sublethal

doses were derived from anecdotal observations during filter paper tests where concentrations 

were measured in μg/cm2 not mg/kg. APHIS would also like to note the researcher’s skepticism 

about toxicity tests where the worms are dosed on saturate filter paper. They wrote: Comparison 

of the results of paper contact test with those obtained in soils clearly demonstrates that the 

contact test has no predictive values for the toxicity of an insecticide in soils, though it is 

important for the initial screening of the environmental chemicals. The differences between 

lowest and highest LC50 values of insecticides for M. posthuma and E. fetida in paper contact 

method were only 6.9 and 2.5-fold respectively while in soil they were over 38 and 26-fold. 

These data demonstrated that worms could tolerate higher concentrations in soil than on moist 

filter paper. This difference in the behavior of the insecticide may probably due to the rate of 

diffusion/uptake of insecticide from the medium into the body of the earthworm. It is well 

reported in the literature that insecticides are adsorbed on soil medium through strong binding 

by organic matter contents in soils (Davis, 1971, Van Gestel and Van Dis, 1988). Hence, the 

availability of insecticide for diffusion will be less from the soil than the impregnated filter 

paper. Contact filter paper test can be used as an initial screening technique to assess the 

relative toxicity of chemicals; however it fails to represent the situation in the soil ecosystem. 

Artificial soil test is more representative of natural environment of earthworms and acute 

toxicity data on several insecticides can be used in the ecological risk assessment on soil 

ecosystem.

Comment 132

APHIS received the following comment, “Carbaryl impacted multiple biochemical biomarkers in 

E. andrei, including Acetylcholinesterase (AChE), methoxyresorufin-O-deethylase (MROD), and 

NADH and NADPH red cytochrome reductase.”

This study exposed earthworms to carbaryl in artificial soil at concentrations of 12, 25 and 50 

mg/kg. The research showed that carbaryl inhibited biotransformation enzyme activities but did 

not induce oxidative stress. Since carbaryl is a cholinesterases inhibitor, changes detected in 
102

acetylcholinesterase activities were not surprising. The acetylcholinesterase activity reduction 

was not complete and the residual activity was stable whatever the dose or the exposure duration 

because of the presence in E. andrei of a non-inhibited, non-specific cholinesterases.

APHIS would like to note the lowest tested soil concentration of carbaryl that caused these 

effects (12 mg/kg) is approximately 12 times greater than the hypothetical concentrations that 

could result from Grasshopper Program treatments where none of the foliar ultra-low volume 

spray settles on vegetation, and the chemical is instantly and uniformly mixed into the top two 

inches of soil.

Comment 133

APHIS received the following comment, “AChE activity was inhibited in E. fetida in two 

studies, one of which resulted in muscular paralysis that directly impacted earthworm burrowing 

capabilities.”

In the first study, carbaryl stock solution was prepared in acetone and water to yield final 

concentrations of 1, 2, 4 and 8 parts per million. Five earthworms were individually exposed for 

5, 10, 20, 40 and 80 minute intervals in a 50ml beaker containing 2.0ml of various 

concentrations of test solution. The researchers asserted the test concentrations used in the study 

were close to expected residues in the soil without any evidence or analysis as proof. They also 

used higher concentrations to exert significant inhibition of AChE activity and loss of burrowing 

in earthworms for establishing a dose effect “correlationship”. These higher exposures occurred 

after the individual worms were rinsed in tap water, their borrowing rate was measured, they

were rinsed again, and then placed back into the solution. Needless to say this systematic dosing 

in a pesticide solution does not match any exposure levels that could result from the application 

of ultra-low volume sprays.

While the significant reduction in the ability of worms to burrow in soil was clearly evident at 

the lowest test concentration (1 ppm) and the earliest period of exposure (5 min), all worms were 

alive and fully recovered to normal behavior (no tremors, efficient burrowing) 18 hrs.

post-exposure to 1 ppm carbaryl.

The second study cited by the commenter measured AChE responses in earthworms exposed to 

carbaryl on filter paper and in a soil media. APHIS has previously noted the difficultly 

extrapolating between filter paper toxicological tests to actual exposure scenarios relevant to the 

Grasshopper Program treatments. While the AChE inhibition reached significance after one day 

of exposure to 0.48 mg/kg carbaryl, the researchers did not conclude there was a reduction of 

burrowing capacity. Pure carbaryl was used as a liquid solution, while Zoril 5 was applied as a 

powder spread on the soil. Zoril 5 was thus more abundant on the superficial soil fraction, and 

was immediately in contact with the animals, whereas pure carbaryl penetrated into the soil and 

probably became bioavailable later. APHIS would also like to note the tested application rate of 

17.8 pounds per acre carbaryl 5% powder formulation (Zoril 5), that was estimated to result in a 

concentration of 4.29 mg/kg was nearly twice the maximum Grasshopper Program carbaryl bait 

rate and had no effect on earthworm AChE activity or the lysosomal membrane stability of 

E. andrei.
103

Comment 134

APHIS received the following comment, “In addition to earthworms, carbaryl negatively 

affected collembola population abundance and reproduction.”

The first and second studies cited by the commenter did not investigate carbaryl or collembola 

(Panda and Sahu, 2004, and Stepić, et al., 2013). The third paper cited used carbaryl as a toxic 

standard for comparison of the effects of other pesticides (Larson et al., 2012). The researchers 

applied carbaryl at a rate of 8.17 lbs. a.i./acre. Researchers conducting the fourth study cited by 

the commenters (Potter et al., 1990) made two applications of carbaryl at the same rate of 8.17 

lbs. a.i./acre, 16 times the maximum rate used by the Grasshopper Program in ultra-low volume 

sprays. The Grasshopper Program only makes one application per year. Therefore this study 

used 32 times the carbaryl rate as the program. In addition, the foliar spray of ultra-low volume 

carbaryl over rangeland is unlikely to result in subsurface soil concentrations comparable to the 

direct turfgrass application made in this study.

The next study cited by the commenters (Joy and Chakravorty, 1991) investigated carbaryl 

toxicity to collembola. Adult specimens of Cyphoderus sp. and Xenylla sp. and Lancetoppia sp. 

were exposed to soils saturated with solutions ranging from 0.5 to 10 ml/l. Although they noted 

the standard agricultural doses of carbaryl 50 WP was 6.25 ml/l, the researchers did not provide 

a sufficient description of their methods for APHIS to make a valuable comparison of the 

exposure rates of the collembola in the experiment to potential exposure levels resulting from 

Grasshopper Program treatments.

The commenters cited another study to suggest carbaryl effected collembola reproduction. Three 

nominal concentrations of carbaryl (1, 4 and 7 mg/kg) in soil chemical behavior and toxicity 

were investigated at different temperatures. After 15 days from soil spiking, it was observed that 

carbaryl concentration in soil decreased to 30% and 33% of the initial concentration at the 

temperature extremes of 8 °C and 28 °C, respectively, and 22.8% of the initial concentration 

under a 20 °C temperature regime. The collembola survival and reproduction were 

significantly affected at 4 and 7 mg/kg concentrations, approximately 4 and 7 times greater than 

hypothetical soil concentrations resulting from Grasshopper Program ultra-low volume sprays 

(see previous comments for estimations parameters).

Comment 135

APHIS received the following comments, “Carbaryl also negatively impacted Prostigmata mites, 

and Tiphia vernalis, a wasp that feeds on scarab beetle larvae in the soil.”

In the first study cited carbaryl applied at a rate of 8.18 lbs. a.i./acre, greater than 16 times the 

Grasshopper Program’s maximum rate, as a toxic standard for comparison of various pesticide 

control efficacy. The effects on oribatid and mesostigmatid mites was not surprising or 

comparable to exposure levels resulting from applications of carbaryl ultra-low volume sprays.

The commenters are mistaken, in that the research cited did not find effects 

on Tiphia vernalis (Helson et al., 1994).
104

Comment 136

APHIS received the following comment, “Carbaryl can be particularly toxic to ground-nesting 

bees, like Andrena erythronii, Bombus terrestris, and Bombus terricola.”

The commenters cited a toxicology study where carbaryl was applied topically to the thorax of 

the bees to investigate lethal doses and determine the concentration values in units of μg a.i./g 

body weight and of μg a.i./bee. This dosing method is not comparable to any exposure scenario 

resulting from the Grasshopper Program treatments using ultra-low volume sprays. APHIS 

would like to note that of the six insecticides tested, carbaryl had the second lowest relative 

toxicity, rather than as the commenter characterized being particularly toxic to ground-nesting 

bees. The researchers noted their study does not suggest an inherent, physiological relationship 

between size and pesticide susceptibility, and they further suggested that bumble bees may be at 

relatively little risk from carbaryl, contrary to the commenter’s suggestion of particular toxicity 

to Bombus terricola. The researcher’s elaborated carbaryl previously was not found to have 

significant effects on bumble bees, citing Hansen and Osgood (1984). 

The acute effects of carbaryl on B. terrestris were investigated for ingestion and topical contact 

in another cited study. The researchers found the calculated hazard ratio for oral exposures of 

carbaryl (309) was below the mean (1399) and the median (381) of the 14 pesticides tested and 

reported. Carbaryl was not found to be toxic through topical exposure at the “highest dose 

advised on the label.” The hazard ratio values permit only a comparative evaluation between the 

different active compounds tested.

Comment 137

APHIS received the following comment, “Carbaryl caused 100% mortality 

in Nomia melanderi when exposed to field-rate pesticide residues 3 hours post-application, 97% 

mortality with 8 hours post-application, and 78% mortality 2 days post application. Carbaryl was 

more toxic than DDT.”

APHIS does not use DDT during Grasshopper Program treatments and does not agree that the 

relative toxicity to carbaryl is a concern. The study cited by the commenter did not test carbaryl 

toxicity on bees, but rather included data from earlier studies. The application rate of carbaryl 

emulated in the earlier studies was I.0 lbs. 80% wettable powder per acre, approximately twice 

the maximum ultra-low volume rate used by the Grasshopper Program. APHIS found the 

literature did not provide sufficient details for a reasonable comparison of the carbaryl 

application methods and rates for additional effects analysis.

Comment 138

APHIS received the following comment, “Bombus impatiens colony vitality (as measured by 

colony weight, worker weight) and the number of workers, honey pots, and brood chambers was 

reduced following carbaryl exposure.”

The researchers noted the confinement of the bee colonies within cages represent a worst case 

scenario in that the workers were caged on the sprayed plots for two or four weeks. Wholecolony consequences of a smaller proportion of the workers foraging on insecticidecontaminated weeds in an open system likely would be less severe. In addition, the researchers 
105

explained extent to which an insecticide is hazardous to pollinators is determined by its inherent 

toxicity as well as the formulation and manner in which it is applied (Stark et al. 1995). For 

example, pollen contamination, which can decimate honey bee colonies, may be exacerbated 

by wettable powder or microencapsulated formulations that have high affinity for binding to 

pollen (Johansen et al. 1983).

APHIS would also like to note the direct application of carbaryl to turfgrass at rates ten times 

greater (5.44 lbs. a.i./acre) than the maximum rate used by the Grasshopper Program (0.5

lbs. a.i./acre) is not comparable to ultra-low volume foliar spray treatments.

Comment 139

APHIS received the following comment, “In a laboratory study, chlorantraniliprole negatively 

inhibited the enzymes acetylcholinesterase and glutathione-S-transferase in Eisenia fetida.”

As previously stated, the Grasshopper Program will not be using chlorantraniliprole in New 

Mexico during 2020. Therefore any chlorantraniliprole exposure scenarios which the commenter 

is concerned about are not relevant at this time.

Comment 140

APHIS received the following comment, “Chlorantraniliprole negatively 

affected Folsomia candida (collembola) reproduction.”

As previously stated, the Grasshopper Program will not be using chlorantraniliprole in New 

Mexico during 2020. Therefore, any chlorantraniliprole exposure scenarios which the 

commenter is concerned about are not relevant at this time.

Comment 141

APHIS received the following comment, “Microscopic examination in an avoidance test 

revealed that the collembola were paralyzed from the chlorantraniliprole treatment and couldn't 

migrate, clarifying an observed avoidance at 1 mg/kg, but no avoidance at any higher 

concentrations. The authors note that chlorantraniliprole may be more toxic to non-target 

arthropods closely related to insects than to other soil invertebrates.”

As previously stated, the Grasshopper Program will not be using chlorantraniliprole in New 

Mexico during 2020. Therefore, any chlorantraniliprole exposure scenarios which the 

commenter is concerned about are not relevant at this time.

Comment 142

APHIS received the following comment, “In the field, ground-nesting bumble bees (Bombus 

impatiens) treated with chlorantraniliprole consumed less pollen than control bees.”

As previously stated, the Grasshopper Program will not be using chlorantraniliprole in New 

Mexico during 2020. Therefore any chlorantraniliprole exposure scenarios which the commenter 

is concerned about are not relevant at this time.
106

Comment 143

APHIS received the following comment, “Staphylinidae (Coleoptera) population abundance was 

slightly but significantly suppressed.”

As previously stated, the Grasshopper Program will not be using chlorantraniliprole in New 

Mexico during 2020. Therefore any chlorantraniliprole exposure scenarios which the commenter 

is concerned about are not relevant at this time.

Comment 144

APHIS received the following comment, “After one application of diflubenzuron, myriapoda

populations were nearly eradicated (73% reduction), gamasina mites were reduced by 40%, 

and uropodina mites were reduced by 57%. Diflubenzuron treatment reduced the populations of 

oribatid mites, prostigmata mites, and soil arthropod larvae, mostly comprised of coleoptera 

and diptera, by nearly 15%.”

The cited research does not suggest Grasshopper Program applications of diflubenzuron will 

result in significant impacts to soil microfauna. The researchers applied diflubenzuron to plots 

and investigated the effects on Collembola, Insecta, Myriapoda, and 4 groups of mites for 6 

months. The observed taxa abundance fluctuated seasonally, but for a majority of taxa no 

significant differences were noticed between the control and exposed plots. The total number of 

microarthropods was insignificantly lower in exposed groups. While myriapods were the only 

taxon that was close to extinction after a single exposure to diflubenzuron the pesticide was 

applied directly to the soil at a rate four times greater than the maximum conventional 

application rate used by the program. The researchers noted their data proved that soil has some 

buffering capacity, and this fact should always be taken into consideration when estimating the 

risk for the environment.

Comment 145

APHIS received the following comment, “In a field study, collembola populations were 

negatively affected by diflubenzuron and did not recover for one and a half years. The 

earthworms, Dendrobaena rubidus and Lumbricus rubellus were reduced in plots treated with 

concentrations of diflubenzuron at half the recommended field rate. Gamasid and oribatid mite 

populations were additionally reduced, and oribatida were observed migrating into deeper soil 

layers to avoid the pesticide.”

The commenters have cited a study where the researchers applied two treatments of 

diflubenzuron wettable powder directly to the forest floor at a rate 37% higher than the 

maximum rate used by the Grasshopper Program. Contrary to the characterization of the 

research findings presented by the commenter, the mean population size of earthworms did not 

differ significantly during the potential effect phase between control and the 137% the 

Grasshopper Program rate treatment plot. The populations of the enchytraeid species 

E. buchholzi, E. minutus, E. norvegicus and M. clavata did not respond to this 137% treatment of 

diflubenzuron applied twice per growing season. While the number of oribatids decreased after 

the application of the insecticides in all experimental plots including the control, these 

differences were only significant in the plot were diflubenzuron was applied directly to the forest 

floor at a rate nearly 14 times greater than the maximum Grasshopper Program rate.
107

Where Brachychthoniid populations declined significantly in the diflubenzuron treated plots, the 

reductions were in part compensated by changes in numbers of the dominant genus Oppiella.

The researchers explained the half-life of diflubenzuron in soil is reported to range from 1 to 27 

days, which was borne out by their data. Therefore, residue accumulations in the organic layer 

is unlikely if diflubenzuron is only applied once per year.

The researchers acknowledged that there could be several potential reasons for differences in 

populations of soil invertebrates between the study plots. First, the plots could differ independent 

of any treatment. APHIS agrees this is a reasonable interpretation because of the small sample 

sizes during the pre-application, potential effect and early recovery data recording phases (I.e. 

four plots including the control, five sample dates, two replicates, n=10). The testing of natural 

variation during the 9 month pre-application phase may not have been sufficient. They decided 

to interpret deviations as a response to a treatment, if numbers in the potential effect phase were 

different to those in the other phases in the same plot and to the control in the same phase.

Comment 146

APHIS received the following comment, “Diflubenzuron treatment resulted in a total loss in 

brood production of male Bombus terrestris, and 100% inhibition of egg hatching success and 

larval growth. Transovarial transport and accumulation of the pesticide in deposited eggs 

explained the total loss of reproduction. Abnormal cuticle formation, which can lead to 

mechanical weakness and death, was observed in dead larvae that worker bees were observed 

removing from treated nests.”

The commenters have cited a study where the B. terrestris was directly dosed with diflubenzuron 

to test acute toxicity. Adult worker bees were exposed via contact by topical application and 

orally via drinking sugar water and by eating pollen. For contact application, 50 μL of the 

aqueous concentration was topically applied to the dorsal thorax of each worker with a 

micropipette. The worker bumblebees were also provided diflubenzuron treated sugar-water for 

drinking for 11 weeks. Bumblebees can also be exposed orally to pollen sprayed until saturation 

with a diflubenzuron concentration. Both the sugar water and pollen were supplied for unlimited 

oral consumption.

While APHIS acknowledges the effects of acute diflubenzuron exposures on the egg hatching and 

larval stages of bumble bees is a concern, the direct dosing conducted by the researchers is not 

comparable to any exposure levels that could result from the Grasshopper Program 

diflubenzuron ultra-low volume spray treatments.

In addition, APHIS would like to note, no acute mortality was observed after topical application, 

nor after oral exposure to treated sugar-water or treated pollen. In all cases, the number of dead 

worker bees in the treated nests over a period of 11 weeks was not above that of the control 

groups using water (0–10%).

Comment 147

APHIS received the following comment, “Multiple studies have observed AChE inhibition in 

earthworms when malathion was applied. Malathion effected the sperm count and viability and 
108

testicular histology of male E. fetida at sublethal concentrations, potentially impairing population 

abundance.”

APHIS agrees with the commenter that the main acute poisonous effect of malathion is the 

inhibition of the enzyme acetylcholinesterase, and acute poisoning such as was carried out by 

the researchers with direct exposures to high concentrations of the pesticide could occur in many 

types of organisms including earthworms. The direct dosing of earthworms to validate their use 

as toxicological test organisms does not mimic any exposure scenario resulting from the 

Grasshopper Program use of ultra-low volume sprays of malathion.

To further illustrate the disparity between exposures resulting from laboratory toxicity tests and 

grasshopper suppression treatments APHIS would like to note the lowest tested concentration 

was 80 mg/kg of soil. The Grasshopper Program applies malathion ultra-low volume spray at a 

rate of 0.62 pounds active ingredient per acre. If a cubic foot of rangeland soil weighs 75 

pounds, 1 acre (43,560 ft.2) of soil two inches deep would weigh 544,500 pounds, or 246,981 

kilograms. The maximum rate used by the Grasshopper Program to apply malathion as an ultralow volume spray is 0.62 pounds (281227 mg) active ingredient per acre. Therefore, the 

maximum concentration of 1.14 mg malathion spray per kg of soil could result from program 

applications. However, this analysis assumes none of the foliar spray settled on vegetation, and 

the malathion instantly absorbed into the top two inches of soil. This hypothetical soil 

concentration resulting from ultra-low volume sprays should not be compared in a risk analysis 

with the 80 mg/kg tested for sub-lethal effects in the laboratory.

As previously stated, New Mexico is very unlikely to use malathion and then only as a last 

resort.

Comment 148

APHIS received the following comment, “In addition to AChE, the biochemical biomarkers 

glutathione-S-transferase, and catalase were also inhibited by malathion in studies 

with Eisenia andrei. Malathion has also been observed to negatively affect the reproduction 

of E. andrei.”

The commenters have cited research that confirms malathion inhibits AChE in earthworms. 

While APHIS does not dispute this effect, the agency doubts such effects could result in 

significant impacts. Notably the researchers found the inhibition period suggests lengthening of 

retreatment intervals to 45 days is the appropriate conclusion from the study. APHIS only makes 

one suppression treatment per year to grasshopper infested rangeland.

As previously stated, New Mexico is very unlikely to use malathion and then only as a last 

resort.

Comment 149

APHIS received the following comment, “Malathion had a severe effect on AChE activity 

in Drawida willsi. Growth, casting activity, and respiration of D. willsi was negatively affected 

by malathion treatment and did not recover for 75, 60, and 30 days, respectively.”
109

The commenters have cited research that confirms malathion inhibits AChE in earthworms. 

While APHIS does not dispute this effect, the agency doubts these biomarker effects could result 

in significant impacts.

The study cited by the commenters described malathion’s recommended agricultural dose as 2.7 

to 4.0 kg a.i./ha and calculated the equivalent 1.5 to 2.22 mg a.i./kg soil, which APHIS would 

like to note are comparable to the concentration estimation provided above. However the toxicity 

results for a single dose of malathion were reported for a concentration of 2.2 mg a.i./kg which 

is equivalent to double the dose of 4.0 kg a.i./acre, nearly six times the application rate used by 

the Grasshopper Program. 

As previously stated, New Mexico is very unlikely to use malathion and then only as a last 

resort.

Comment 150

APHIS received the following comment, “In addition to AChE, the biochemical biomarkers 

glutathione-S-transferase, and catalase were also inhibited by malathion in studies 

with E. andrei. Malathion has also been observed to negatively affect the reproduction 

of E. andrei.”

The commenters have cited two toxicology studies where earthworms were placed in test tubes 

lined with malathion saturated filter paper to determine acute effect concentrations, extrapolated 

from the biomarker, AChE reduction. The dosing methods and units of ug a.i./cm2 are not 

comparable to any exposure levels that could result from the application of malathion ultra-low 

sprays by the Grasshopper Program. The study cited by the commenter did not make any 

conclusions regarding malathion affecting reproduction of E. andrei.

As previously stated, New Mexico is very unlikely to use malathion and then only as a last 

resort.

Comment 151

APHIS received the following comment, “In a lab test rating the toxicity of 45 pesticides 

to E. fetida, malathion was ranked moderately toxic with an LC50 of 114.4 ug/cm.”

The study cited by the commenter was a comparison of the toxicology of 45 pesticide to 

determine the LC50. These studies exposed earthworms to varying concentrations of carbaryl to 

determine toxicological endpoints. Based on the extremely high doses, the impact to the survival 

of earthworms was not only unsurprising, but the object of the studies. APHIS would like to note 

this laboratory dosing procedure is not comparable to any exposure scenario resulting from the 

use of malathion ultra-low volume sprays by the Grasshopper Program.

As previously stated, New Mexico is very unlikely to use malathion and then only as a last 

resort.
110

Comment 152

APHIS received the following comment, “Malathion caused a 40% decrease in survival of the 

ground-nesting bee, Nomia melanderi.”

The study cited by the commenter did not test malathion toxicity on bees, but rather included 

data from earlier studies. The application rate of malathion emulated in the earlier studies was 

I.0 lb. of emulsifiable concentrate per acre, significantly greater than the maximum ultra-low 

volume rate used by the Grasshopper Program. APHIS found the literature did not provide 

sufficient details for a reasonable comparison of the malathion application methods and rates 

for additional effects analysis.

As previously stated, New Mexico is very unlikely to use malathion and then only as a last 

resort.

Comment 153

APHIS received the following comment, “The EAs an agency action subject to this consultation 

requirement, must be prepared “concurrently with and integrated with environmental impact 

analyses . . . required by . . . the Endangered Species Act of 1973.”

The commenter has again confused the EA prepared by APHIS for the Grasshopper Program in 

New Mexico with other environmental risk analysis documents. See comment/response 154.

Comment 154

APHIS received the following comment, “In order to properly provide information to the public 

for commenting on the EIS and the EAs, the section 7 process should be completed prior to the 

completion of NEPA. APHIS must ensure that consultation addresses all species and critical 

habitat that could be directly and indirectly affected by the proposed project.” The comment also 

states that APHIS has not complied with its responsibilities under Section 7 of the ESA. The 

comment also states “APHIS touts the fact that it completed Section 7 consultation with the 

National Marine Fisheries Service in 2010. However, there are zero species under NMFS’s 

jurisdiction in the State of New Mexico...”.

The draft EA provided a summary of the consultation work for the Grasshopper Program across 

all States. APHIS recognizes that no listed species under NMFS jurisdiction occur in New 

Mexico. Reference to the NMFS BA was removed from the final EA. APHIS consultations with 

the FWS are completed at the local level prior to any treatments. No APHIS treatments are made 

in States without prior concurrence from the FWS regarding federally-listed species. APHIS 

consulted with the FWS on federally-listed species that may occur within the county or areas 

where grasshopper and Mormon cricket treatments may be required. APHIS works closely with 

the FWS to determine the application of protection measures and where those measures should 

be applied prior to any treatments. A copy of the letter of concurrence (# 02ENNM00-2015-I0244) is included in the final EA as an appendix. The letter was issued in 2015 and valid 

through 2020.

APHIS also submitted a programmatic biological assessment to the FWS in 2015. APHIS is 

currently working with the FWS to update and complete the biological assessment and receive 
111

concurrence. The intent of the programmatic biological assessment is to provide consistent 

mitigation measures for listed species that may co-occur with Program treatments. In the 

meantime consultations with the FWS are still being completed at the local level prior to any 

treatments.

Comment 155

APHIS received the following comment, “The EA mysteriously states that “[b]ased on an 

assessment of the potential exposure, response, and subsequent risk characterization of program 

operations, APHIS concludes the proposed action is not likely to adversely affect listed species 

or critical habitat in the program area.” This conclusive statement, unsupported by 

documentation of any manner of ESA consultation, fail to meet the ESA’s requirements. 

“Appendix D: FWS/NMFS Correspondence, provides no information on any correspondence, 

and to the extent some tracking numbers are provided, there is no evidence of any contact within 

the past half decade. APHIS claims to have requested concurrence from the U.S. Fish and 

Wildlife Service on these conclusions, but this request is not provided or referenced anywhere.”

Local FWS Section 7 consultations were completed in 2015. USFWS granted a letter of 

concurrence that is valid through 2020. A copy of the letter of concurrence (# 02ENNM00-

2015-I-0244) is included in the final EA as an appendix. Research for new species listings is 

completed on an annual basis utilizing the FWS ECOS system.

Comment 157

APHIS received the following comment, “APHIS would unlawfully be making an irreversible or 

irretrievable commitment of resources if it allows insecticide application on rangeland 

grasshoppers and/or Mormon crickets to occur prior to receipt of a final biological opinion from 

FWS. APHIS will run afoul of its Section 7 ESA requirements if it chooses to move forward, and 

it will also likely violate the ESA’s prohibition against the take of endangered species as 

described by Section 9 of the statute if it moves forward with this project prior to properly 

completing its Section 7 duties. Even where there is a letter of concurrence, APHIS would still 

fail to comply with the ESA because informal consultation does not authorize the incidental take 

of federally-listed species nor does it authorize the adverse modification or destruction of critical 

habitat.”

APHIS has been able to complete informal consultation with the FWS regarding the APHIS 

Grasshopper Program at the State level. Formal consultation has not been required since the 

FWS has concurred with the APHIS determinations of not likely to adversely affect, including 

any associated critical habitat. Since APHIS has complied with Section 7 through informal 

consultation APHIS has not violated Section 9 of the ESA, nor has formal consultation been 

required resulting in a biological opinion.
112

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