USDA APHIS PPQ 13

USDA APHIS PPQ

Emerald Ash Borer Survey Guidelines

Introduction

Survey for emerald ash borer (EAB) has undergone an evolution of tactics, scope, and 

application since discovery of the pest in 2002. Survey was originally based on visually 

detectable symptoms (D-shaped EAB exit holes, longitudinal bark cracks, epicormic branching, 

woodpecker feeding sites, etc.) survey was changed to girdled trees, then to the use of traps 

with lures.

Visual survey was applied at various levels of intensity and with various techniques (e.g., 

ground surveys, ladders, climbing devices, bucket trucks). While visual surveys are unlikely to 

detect newly infested trees, they are useful when setting up EAB parasitoid release sites.

Since 2012, trap placement has been based on a survey sampling design developed in 

collaboration with the APHIS EAB Program and the U.S. Forest Service’s Forest Health 

Technology Enterprise Team. The current EAB survey will use similar methodology based 

on last year’s survey, but will not be part of the PPQ EAB program. This computergenerated EAB survey sampling design product combines a scientific model of the 

likelihood of detecting EAB with historical EAB detections. Simply stated, the survey 

sampling design model will provide general geographic areas to deploy EAB traps resulting 

in the highest probability of pest detection. 

Since the EAB program is placing a greater emphasis on biocontrol activities, the use of traps 

for detection of EAB will receive less emphasis. Traps and lure will remain available for our 

cooperators while supplies last. As of January, 2020 some 13,000 purple prism traps and 

55,000 Z-3-hexenol lures were available for distribution from our Mission warehouse. 

Survey Objective

The EAB Program will not conduct a national survey but will support cooperators to determine 

whether additional pockets of infestation may exist undetected surrounding the known infested 

areas, to better define the leading edge, and mainly to identify areas for future biological control 

activities. The objective of the survey is to detect further spread of EAB along the leading edge 

and to find suitable locations for the release of biological control organisms.

Visual survey

Visual surveys should be based on symptoms, such as epicormic shoot growth, declining or dead 

canopy, longitudinal bark cracks, woodpecker damage and D-shaped EAB exit holes. Visual 

survey is not very effective for newly infested areas, as these infestations are often high in the 

canopy, but when trees become more heavily infested, they will be easier to detect and may also 

be amenable to the deployment of EAB parasitoids. (See Appendices A and C of the EAB 

Biological Control Release and Recovery Guidelines for more signs of EAB infestation.

All survey and public outreach activities should be coordinated with Tribes, Federal, State, 

and local agencies and organizations to ensure efficient use of resources.
USDA APHIS PPQ 14

Trap Placement Protocols

The risk-based sampling design generates a science-based, survey within a 100 mile buffer area 

near newly detected EAB infestations. The sampling design identifies locations where traps may 

be placed identified by latitude, longitude, county, and state.

Trap placement should be coordinated with State Plant Regulatory Officials and Tribal 

governments where Tribal lands are involved. Coordination also should occur with other Federal, 

State, and local agencies, and non-governmental organizations involved in the program. To 

ensure the highest probability of detecting EAB, traps should be set in trees that meet the criteria 

as described in the Trap and Sign Placement paragraph on page 5 of these guidelines.

The list of trap locations generated by the survey sampling design includes the latitude and 

longitude for the center point of each location in which a trap is to be placed. Navigating to each 

location will require the use of a global positioning system (GPS) unit. Set-up and guidance 

information for GPS units is provided in Appendix B on page 16.

FIGURE 1. Emerald ash borer survey map (Please see page 19 for larger format map).

A limited number of threatened and endangered species of insects could be caught in the purple 

prism trap. These species include the delta green ground beetle, Hine’s emerald dragonfly, 

Mitchell’s satyr butterfly, Saint Francis’ satyr butterfly, the Laguna mountains skipper, and the 

valley elderberry longhorned beetle. Sampling locations within critical habitat areas for 

potentially affected threatened and endangered insect species were discarded from the sampling 

design. Traps must not be set in critical habitat areas for these species. In addition, to avoid 

inadvertent capture of Karner blue butterflies, traps should not be set in jack pine and oak 

savannah with well drained sandy soils habitat in Massachusetts, New Hampshire, New York, 

and Wisconsin. Please consult EAB Program management for guidance if needed.
USDA APHIS PPQ 15

In locations where high-risk facilities or conditions are present and suitable ash trees are located, 

traps should be located in an ash tree as near as possible to the high-risk facility. Prioritized highrisk facilities should include:

1. Campground, recreation area, cottage community, summer camp

2. Major transportation artery, rest area, truck stop

3. Sawmill, firewood dealer, nursery, tree care company

4. Recently landscaped residential and commercial property

5.Site of high attendance/ high profile cultural event: Pow-Wow ground, hunting lodge, 

NASCAR track, horse trail ride site, motor cross site, rafting and fishing camp

NOTE: Ash trees within the location exhibiting two or more of the symptoms listed below should 

also be examined using destructive sampling techniques (i.e., the removal of bark to inspect for 

EAB):

 Canopy stress/dieback

 Epicormic shoots/suckering

 Bark splits

 Woodpecker damage

 D-shaped exit holes (3-4 mm diameter)

 Larval galleries

Conducting Survey and Inspections:

 Identification of most suitable site and tree within the designated location

 Distribution of educational material where appropriate

 Placement and maintenance of traps

 Visual survey of the environment for ash trees exhibiting signs and symptoms of 

EAB in proximity of the traps.

NOTE: For various reasons it may not be possible to place a trap in a location as designated 

by the survey sampling design. Those locations must be recorded according to the following 

definitions:

Omitted: The location is inaccessible – no trap can be set

Declined: The location is viable but survey resources are limited – no trap can be set

Purple Prism Trap Assembly and Placement

Timing of Trap Placement: Research indicates that an accumulation of 450 growing degree days 

(base 50oF) results in initial emergence of EAB adults. Traps should be placed just prior to 450 

growing degree days (GDD) and lure replacement is recommended to occur just prior to the 60 

day expiration date. In order to assist States with timing of trap placement, a map of the United 

States depicting predictive areas of initial emergence are appended to this document (Please see 

page 20 for GDD map). Appendix C (see page 17) defines, by state, when initial emergence is 

predicted to occur.

Trap: A prism trap consisting of three 14” x 24” panels with several holes for trap and lure 

attachment (Fig. 2) will be used. The trap is constructed from a sheet of pre-glued purple 

corrugated plastic. An instructional video detailing trap assembly and use can be found on the 

APHIS website under Pest Management here. (Please note that when assembled the pre-glued 

face of the panels should be the exterior face.)
USDA APHIS PPQ 16

After the trap is assembled into its prism shape, spreaders are attached to the trap at holes (labeled

3 in Fig. 2). The lure is attached to a loop on the spreader using a cable tie (Fig. 3).

FIGURE 2: Prism trap diagram

FIGURE 3: Lures hung from loop on spreader using a cable tie

Lure: One pouch of (Z)-3-hexanol lure is recommended to be attached to each trap. The lure 

provided by commercial firms is produced as a pouch and designed to last in the field for 60 days. 

Lure attachment to the trap should be reinforced with duct tape placed at the very top to ensure 

continued attachment during inclement weather. Do not cover the lure with duct tape as that will 

inhibit the release of the lure. If possible, any unused lure remaining at the end of the trapping 

season should be stored (refrigerated or frozen) for future use in EAB surveys. Research suggests 

that the Manuka oil lure provides a negligible increase in trap efficacy, therefore the EAB 

Program has decided to discontinue its use in the national survey. However, any remaining 

Manuka oil lure from previous surveys within the past two to three years may also be used.

Lure Handling, Transport, and Storage:

The (Z)-3-hexenol lure pouches emit odors and volatiles which pose safety and health concerns in 

confined spaces. EAB Program managers have worked closely with the APHIS Safety and Health 

managers and the lure manufacturer to develop protocols for the safe handling, transport, and 

storage of the lures. In summary, prior to deployment, lures must be kept cold at all times by 

storing in a freezer. During transport, lures must be kept in coolers with cold packs or ice and 

stored in isolation from the vehicle’s cab, or, as an alternative, kept in coolers with screw top lids 

that also must be chilled with cold packs or ice. Coolers should be labeled “NOT FOR FOOD OR 

BEVERAGE USE”. To avoid skin irritation during handling, gloves may be worn. Additional 

information and precautions can be found in a Job Hazard Assessment and Material Safety Data 

Sheets for the lure pouches and are available from the local APHIS PPQ SafetyCoordinator or 

supervisor for more details.
USDA APHIS PPQ 17

Trap and Sign Placement: Traps must be placed in ash trees (Fraxinus spp.). If possible, ash 

trees should be 8” or greater in diameter with larger or largest ash tree in a stand of trees located 

along edges, in open areas, or in open stands such as in parks within the grid cell. Traps should 

be placed in the lower to mid canopy, but with the bottom edge of the trap no lower than five feet 

above the ground. They should be placed on the sunny side of the tree, most typically, the south 

or southwest side.

FIGURE 4: Purple prism trap hung using a telescoping pole

A wire hanger will be used to hang purple prism traps (Fig. 4). A telescoping pole that extends to 

24’ (different models are available at home improvement stores and other retailers), and fitted 

with a hook to place the purple trap in one of the lower limbs, is recommended. The full 

extension of the pole may or may not be necessary. If all limbs are too high to reach with a pole, 

a throw line may be tossed over a limb, and a rope with a trap attached may be hoisted up into the 

canopy (Fig. 5).

FIGURE 5: Purple prism trap hung using a rope
USDA APHIS PPQ 18

Trap Maintenance: A lure will last approximately 60 days and should be replaced just prior to 

expiration. Traps should be inspected for adult EAB at the time of lure replacement.

If trap surfaces are loaded with debris, they should be renewed by removing the debris and 

scraping the sticky compound. Scraping can be accomplished with a trowel or putty knife. If 

necessary, stickier compound can be added using a paint roller or trowel. The sticky surface 

should remain intact throughout the season unless a trap is allowed to come in repeated contact 

with an adjacent branch or tree bole. Traps must not be removed prior to August 1 and before 

1,500 GDDs have been exceeded.

Trap Disposition: While the polypropylene material of the traps is recyclable, the sticky 

compound that is adhered to the panels renders the traps undesirable to most recyclers.

Alternatively, one may seek a user of waste fuel material for trap disposition. Hangers and 

spreaders are reusable and should be retained for future use. Hangers and spreaders that cannot 

be reused should be recycled.

Lindgren Green Multi-funnel Trap Assembly and Placement

Timing of Trap Placement: The timing for placement of Lindgren green multi-funnel traps is 

identical to the purple prism trap. Research indicates that an accumulation of 450 growing degree 

days (base 50oF) results in initial emergence of EAB adults. Traps should be placed just prior to 

450 growing degree days (GDD) and lure replacement is recommended to occur just prior to the 

60 day expiration date. In order to assist States with timing of trap placement, a map of the U.S. 

depicting predictive bands of initial emergence are appended to this document (see page 20 for 

GDD map). Appendix C (see page 17) defines, by state, when initial emergence is predicted to 

occur.

Trap: The trap is constructed from 12 green plastic funnels with a green dome-shaped top and a 

plastic collection cup at the bottom. Trap funnels and the dome are held together by black pegs. 

The collection cup is secured to the bottom with a twist-on motion. An eye screw at the top of 

the trap is used for rope attachment (see Figs. 6, 7). Multi-funnel traps are pre-assembled and 

pre- coated in a 1:1 solution of Fluon before shipment to field locations. The Fluon application 

provides a slippery surface that assists with the capture of EAB. Due to the modular nature of the 

traps, some minor assembly may be required.

FIGURE 6: Multi-funnel traps hanging in ash trees
USDA APHIS PPQ 19

Trap hanging: A rope should be thrown over a branch at approximately 16-26’ above the ground. 

The limb hanger and pole should not be used for hanging the multi-funnel trap. The branch 

should be alive and sturdy (> 2” diameter), as smaller or dead branches could snap under the 

weight of the trap. An arborist throw weight (12, 14, or 16 oz.) can be tied to one end of the rope. 

Take care to clear the rope from all lower branches so that the trap can be pulled up and down 

like an elevator when servicing. The rope should have a clear path to the ground. The trap may 

need to be raised and lowered at an angle from the tree to accomplish this. Give yourself enough 

slack so that you can tie the rope to an adjacent tree.

A bowline knot, similar to the one shown here is the preferred method: 

(http://wow.uscgaux.info/content.php?unit=081-07-04&category=knots-know-how) 

Using these knots, tie the rope to two points on each trap. For the multi-funnel trap these points 

are the top metal hanger and one of the three holes on the bottom funnel used for peg attachment. 

The knot is important as high winds will sometimes cause the traps to come down if the knots are 

not tied properly.

When hanging the traps try to rest the top of the trap against the bottom of the tree limb. This 

should prevent the rope from twisting on itself. When attaching the collection cup, take care to 

make sure that it is securely attached to the bottom funnel.

FIGURE 7. Green multi-funnel trap with attachment points for ropes and lures.

Prior to raising the trap in the tree, fill the cup with approximately 2 inches of propylene glycol 

(RV antifreeze; usually pink in color). Do NOT use any product containing ethanol as products 

containing this will evaporate over time, especially in hot, dry climates or under drought 

conditions. Propylene glycol should not be diluted with water prior to filling the cup as it will be 

diluted by rainwater over time.
USDA APHIS PPQ 20

Once the trap is hoisted, tie it off to a tree (the one the trap is hanging from will work for this). 

Take care when tying this rope off to place it out of the reach of children or others who may 

want to pull it down.

Trap checking: When checking the multi-funnel trap, the contents of the trap should be poured 

through a paper filter. A paper cone paint strainer is the preferred method (Fig. 8), although a 

coffee filter may also work but will retain more moisture. The strainer should then be placed 

inside a leak proof plastic bag. While wire closed bags (e.g., Whirlpaks) are the preferred 

method, a plastic zipper (e.g., Ziploc) bag will also work. Please make sure to label and seal the 

bag completely to prevent leaks. A small amount, such as one teaspoon, of ethanol may be added 

to the bag to help preserve the specimens for sorting in the lab. As long as the liquid in the cup is 

still pink, and does not smell too badly, it can be reused instead of discarded during traps checks. 

Place a propylene glycol collection container under the filter when pouring out the sample.

FIGURE 8. Paper cone paint strainer containing a sample of beetles

A (Z)-3-hexanol lure pouch should be hung from the lower loop of the prism trap spreader or 

from one of the holes used for peg attachment near the top of the multi-funnel trap with a small 

plastic cable tie. The lure should be changed before its expiration in 60 days.

Trap and Lure Handling, Transport, and Storage:

EAB Program managers have worked closely with the APHIS PPQ Safety and Health Managers 

and the trap and lure manufacturers to develop protocols for the safe handling, transport, and 

storage of our traps and lures. The green multi-funnel trap is coated with a fluoropolymer resin 

commonly referred to as “fluon”. EAB Program uses manufacturer pre-treated “fluon” traps only 

for program use. This slippery resin may be an irritant to some which can be negated through the 

use of nitrile gloves during handling. Eye protection, such as vented splash goggles and face 

shield, should be worn while raising the trap into position in order to avoid any propylene glycol 

spillage contacting the eyes. The (Z)-3-hexanol lure pouches emit odors and volatiles which pose 

safety and health concerns in confined spaces. Prior to deployment, lures must be kept cold at all 

times by storing in a freezer. During transport, lures must be kept in coolers with cold packs or 

ice and stored in isolation from the vehicle’s cab, or, as an alternative, kept in coolers with screw 

top lids that also must be chilled with cold packs or ice. Coolers should be labeled “NOT FOR 

FOOD OR BEVERAGE USE”. To avoid skin irritation during handling, gloves may be worn. 

During handling of lure, open down-wind in an open well-ventilated environment. Additional 

information and precautions can be found in a Job Hazard Assessment and Safety Data Sheets for 

“fluon”, propylene glycol, and the (Z)-3-hexanol lure pouches in each sites specific Safety Data 

Sheet manual. Contact your local APHIS PPQ Safety Coordinator or supervisor for more details.
USDA APHIS PPQ 21

Trap and Sign Placement: Traps must be placed in ash trees (Fraxinus spp.). If possible, ash 

trees should be 8” or greater in diameter with larger or largest ash tree in a stand of trees located 

along edges, in open areas, or in open stands such as in parks within the grid cell. Traps should 

be placed in the lower to mid canopy, but with the bottom edge of the trap no lower than five feet 

above the ground. They should be placed on the sunny side of the tree, most typically, the south 

or southwest side.

Trap Maintenance: The lure will last approximately 60 days and should be replaced just prior to 

expiration. Multi-funnel traps should be checked every two-three weeks and any insects that are 

captured should be collected. When reattaching cups, please make sure that all pegs are securely 

locked in place as they may come loose under some weather conditions.

Trap Disposition: Multi-funnel traps are designed to be used over several field seasons. At the 

end of the season, the collection cups may be gently scrubbed, and dirt may be wiped away from 

funnels with a cloth, take care not to remove too much of the slippery Fluon coating. Traps will 

collapse into a smaller form for storage and subsequent reuse.

Screening for Suspect Buprestidae and Specimen Submission

Any suspect Buprestidae adult or suspect EAB adult specimen collected from a trap in a nonquarantined county should be placed in a dry vial. If the specimen is from a purple prism trap, use 

the sticky compound from the trap to stick the specimen to the side of the vial and/or gently pad 

with soft tissue placed into the vial on top of the specimen(s) to prevent damage during shipping. 

Sorted specimens collected from Lindgren traps should be placed in a vial and gently padded with 

soft tissue placed into the vial on top of the specimen(s) to prevent damage during shipping. 

Larval samples need to be shipped in a vial containing 70% ethanol. (If guidance is needed on 

proper packaging to ship larvae in ethanol, please contact your local PPQ Safety Coordinator.) 

All suspect specimens should be delivered to the State Plant Health Director or an APHIS 

representative to be packaged and shipped to Dr. James Zablotny along with a completed 

“Specimens for Determination” PPQ Form 391. Be sure to include any survey record number and

GPS coordinates on the PPQ Form 391 so identified specimens can be linked to survey records.

Dr. James Zablotny 

USDA, APHIS, PPQ

11200 Metro Airport Center Drive, Suite 140 

Romulus, MI 48174

Phone: 734-942-9005

E-mail: james.e.zablotny@aphis.usda.gov

Dr. Zablotny will make a determination and send specimens to the Systematic Entomology 

Laboratory (SEL), if necessary, for initial State detection confirmation.

Any suspect Buprestidae adult or suspect EAB adult specimen collected from a trap in a 

quarantined county should be placed in a dry vial. Using the sticky compound from the trap, stick 

the specimen to the side of the vial and/or gently pad with soft tissue placed into the vial on top of 

the specimen(s) to prevent damage during shipping. Larval samples need to be shipped in a vial 

containing 70% ethanol. (If guidance is needed on proper packaging to ship larvae in ethanol, 

please contact your local PPQ Safety Coordinator.) All suspect specimens should be delivered to 

the State Plant Health Director or an APHIS representative to be packaged and shipped to Mr.

Bobby Brown along with a completed “Specimens for Determination” PPQ Form 391. 
USDA APHIS PPQ 22

Be sure to include any survey record number and GPS coordinates on the PPQ Form 391 so 

identified specimens can be linked to survey records.

Mr. Bobby Brown 

USDA, APHIS, PPQ

901 W. State Street

Smith Hall, Purdue University 

West Lafayette, IN 47907-2089

Phone: 765-496-9673

E-mail: robert.c.brown@aphis.usda.gov

Data Management Structure:

APHIS wants to make it clear that the national “Integrated Plant Health Information System” 

(IPHIS) is not required as a field data collection tool, however operationally specific data is of 

great importance and therefore APHIS has designated the IPHIS application to be utilized as the 

final holding tank or centralized database for EAB data.

IPHIS requires internet access, USDA eAuthentication credentials, and approved access to an 

IPHIS or cooperator office. If you need USDA eAuthentication USDA employees should contact 

their supervisors, and all other cooperators should work through their State Plant Regulatory 

Official and State Plant Health Director.

After receiving network access, eAuthentication credentials and IPHIS access, users can log into 

the system and utilize two types of data entry methods. These include the IPHIS web interface 

and an Excel spreadsheet to upload files. The AllInOne Excel spreadsheet upload file, for initial 

trap installations and omits, is also available here.

Please use the IPHIS template “EAB Natl Survey” for capturing EAB trapping and omit data.

Note: IPHIS can now receive unlimited uploaded records in a spreadsheet.

The data fields created for the 2012 through 2019 EAB surveys are also used in the EAB survey. 

APHIS does not ask surveyors to collect symptom data, and the fields for diameter at breast 

height (DBH) and trap height are optional. Additional optional fields include: (1) site type 

categories and additional free text, (2) a field for assigned locations with no trap placement, 

including omitted and declined locations, and (3) fields to record omit reasons for assigned grids 

and comments.

Please record the state’s assigned grid number as IPHIS’ Location Name; the IPHIS site name can 

also be assigned this value. Traps placed outside assigned grid number cell locations should use 

the following naming convention for location name:

2 letters for state designation + 3 letters for surveyor’s initials + 3 digit sequential trap number 

(e.g., IAJAD003 for Iowa, John A. Doe, Trap 3).

The state’s sequential trap number begins with 001 for the first trap not having an assigned 

grid number and increases by one for each additional trap; second trap is 002, the third is 003 

and so on.

For consistency with other state trapping programs, we encourage users to use existing 

procedures and tools for recording data in the field. A field data form for the manual recording of 
USDA APHIS PPQ 23

data is in Appendix D. Organizations using paper, spreadsheets, or third party software can enter 

data directly into the web interface or “bulk” upload data from the Excel spreadsheet using the 

web upload tool.

It is very important for survey personnel to upload data every other week throughout the

season!

Technical Support

1 (877) 944-8457 (select option 3) 

6:30 am to 8:00 pm ET, Monday - Friday

Communication:

The risk-based survey sampling design continues to determine trap dispersal. A variety of 

materials will be developed to facilitate communication and understanding among key audiences 

who include Federal, State, and Tribal partners, survey cooperators and contractors, the media, 

and the public at large. Materials will include but are not limited to key messages, talking points, 

and Frequently Asked Questions (FAQ’s).

The highly visible purple prism traps and Lindgren green multi-funnel traps generate curiosity 

which often results in public questions and media inquiries. Individuals involved in the actual 

placement and maintenance of traps should be conversant with survey messages and understand 

media protocols. Furthermore, the EAB survey provides an opportunity to communicate other 

program messages addressing control, regulation, and the human-assisted spread of the pest.

Communication staff and program personnel should also be broadly familiar with the core 

program messages about these issues.

Outreach & Education:

The active participation of target audiences to assist in preventing the spread of emerald ash borer 

throughout the United States is critical. Outreach is an integral element of the EAB Program 

supporting regulatory, survey, and control.—It is a basic task for all program staff and a valueadded opportunity for each personal encounter, engagement, or exchange. Formal strategic 

communication and outreach campaigns targeting industries that move regulated material should 

be implemented together with public awareness campaigns designed to provide education to 

citizens about the dangers of moving infested host materials such as firewood. Since the beetle is 

difficult to detect, the more people trained to identify EAB symptoms or damage and report 

suspects, the greater the opportunity for successful outcomes. Outreach activities encourage the 

public to recognize and report possible beetle damage in their area as well as suspected incidents 

of quarantine violations.
USDA APHIS PPQ 24

Appendix A. Details of Survey Sampling Design Construction.

The EAB survey employs a computer-generated risk assessment product to guide the 

deployment of detection tools in a way which results in the following benefits:

 increase the number of successful EAB detections outside the known infested area

 improve land managers capability of detecting EAB close to the date of a new attack

 find locations that are best suited to implement biological control

The EAB risk assessment model was developed using a combination of statistical models for 

predicting where EAB was most likely to be detected. This is amajor change in modeling procedure 

from years prior to 2016, which employed the MaxEnt statistical model, which used only positive 

detections for EAB. Given the last few years of nationally consistent data collection which reports 

both positive and negative detections, APHIS upgraded the models to utilize that information in order 

to avoid some major statistical assumptions regarding the data, and discovered that all the models 

concurred in predicting risk in the known infested area but differed widely in extrapolating that risk 

to outside the infested area. This is consistent with knowledge concerning the difficulty of pest 

detection, so an “ensemble” of the models was created to mitigate model uncertainty between 

statistical platforms. There were two model applications for each statistical platform, both using all 

2011-2017 trap data: one model included the distance from any prior year positive trap as a predictor 

variable (modeling active spread) and one model did not include distance from prior detections as a 

predictor variable (modeling full geographic potential).

EAB is an actively spreading pest and a false negative could be reported for two reasons: 1) the 

location is suitable but not yet infested, or 2) the pest is present but undetected. Utilizing negative trap 

location could be too restrictive in the model fitting process because of the potential for false 

negatives. While MaxEnt demonstrates flexibility regarding the “potential” of locations of having a 

pest present, we found that MaxEnt’s default assumption of pest prevalence (EAB can occupy up to 

50% of the landscape) caused great overestimation of risk compared to models that utilized actual 

absence information. Since the EAB risk assessment model is updated each year, APHIS is mitigating 

the issue by allowing the model to update with new information as the pest invades new 

environmental gradients.

Four parameters were required to run the models. These were:

1) the dependent detection data from the APHIS IPHIS dataset (2011-2018), which consists of both 

negative and positive trap data

2) selected independent variables that correlate with the presence of EAB

3) a defined geographic area of interest.

4) modeled negative trap data limited to traps within 60 km of a positive trap.

The independent variables were selected in the previous year using the following sources:

1. scientific literature

2. expert opinion

3. anecdotal evidence

4. correlation analyses

5. preliminary statistical analyses.
USDA APHIS PPQ 25

Dissemination of trap resources is thus determined by this EAB risk assessment model, combined 

with a spatially balanced sample design. The model has a known inclusion probability for every 

grid cell and provides an objective and transparent methodology for selecting trap locations. Since 

we are utilizing an ensemble model which is actually a percentage of model agreement of pest 

presence (rather than risk of pest presence like in previous years), the sample design will utilize 

this ranking of model agreement as the inclusion probability surface. The sampling design 

increases spatial independence among sample locations and therefore, maximizes sampling 

efficiency and provides the most information available per sample unit.

Each trap location is recommended for placement within a one kilometer square grid cell designated 

within a United States grid cell, each with a unique identification, and also by the center point of the 

grid cell (identified by latitude and longitude).
USDA APHIS PPQ 18

Appendix B. GPS Guidance and Sample Location Information

Initial Requested Information

1. Field Crew Name

a. Crew ID (State and Affiliation (i.e., PPQ, State Dept. of Ag., Contractor, Volunteer) 

should be associated to the Crew ID)

Initial GPS Unit Setup Guidance

1. Depending on your GPS unit and what options that are available to you, please use the 

following guidance for collecting position information.

a. WGS 84 geodetic datum

b. Latitude/Longitude collected in Decimal Degrees format

c. Satellite Almanac (where applicable): Download the most recent Satellite Almanac to 

your unit.

d. Wide Area Augmentation System (WAAS) to improve the accuracy of the positions

Helpful Tips for Collecting Information at the Site

1. Turn the GPS unit on and allow the GPS unit to start gathering data when you arrive at the 

tree in which the trap will be hung. It may be helpful to turn the GPS unit on when you leave 

your vehicle.

2. Place the unit in a stable location while hanging the trap.

3. Collect location data at the tree in which the trap is hung

4. Ensure that you are collecting a signal from at least four satellites.

5. Location Data Collection

a. Location Name for Grid Cell = Cell_ID

i. When recording the Cell_ID (Location Name) in IPHIS, the Samp_ST_ID 

code assigned to each cell designated as a trap placement site by the survey 

design should be used if available. For cells which do not have a 

Samp_ST_ID code assigned, please use the following naming convention: 2 

letters for State designation, 3 letters for surveyor’s initials, and 3 numbers 

for trap number, e.g., IAJAD003, (Iowa, John A. Doe, Trap 3). Each 

surveyor should begin with 001 for the first trap which does not have an 

assigned Cell_ID and increased by one for each subsequent trap (the second 

such trap is 002; the third is 003 and so on).

b. Please see Appendix D for EAB Field Data Form.

c. Latitude/Longitude

d. Omitted - with drop down list of potential reasons for the omitted cell (e.g. steep 

slope, inundated with water, dangerous terrain, dangerous neighborhood, etc.)

e. Notes for the surveyor’s assessment of the site conditions (e.g. firewood, riparian, 

wooded lot, campground, lumber/saw mill, suburban, urban, new development, tree 

service company, etc.

6. NOTE: It is very important for survey personnel to upload data every other week 

throughout the season!
USDA APHIS PPQ 19

Appendix C. Predicted Growing Degree Day Zones for Initial EAB Emergence (~400-500Growing 

Degree Days, base 50)

Alabama Feb 1

Alaska June 22

Arizona Feb 1

Arkansas Mar 15

California Feb 15

Colorado Apr 22

Connecticut May 22

Delaware Apr 22

Florida Jan 22

Georgia Feb 15

Hawaii Jan 22

Idaho May 22

Illinois Apr 22

Indiana Apr 22

Iowa May 1

Kansas Apr 8

Kentucky Apr 8

Louisiana Feb 15

Maine June 1

Maryland Apr 22

Massachusetts May 22

Michigan May 22

Minnesota May 22

Mississippi Feb 22

Missouri Apr 1

Montana June 1

Nebraska May 1

Nevada Feb 22

New Hampshire June 1

New Jersey May 8

New Mexico Mar 1

New York May 15

North Carolina Mar 22

North Dakota June 1

Ohio May 1

Oklahoma Mar 5

Oregon May 22

Pennsylvania May 1

Rhode Island June 1

South Carolina Mar 8

South Dakota May 15

Tennessee Apr 1

Texas Jan 22

Utah May 11

Vermont June 1

Virginia Apr 8

Washington May 22

West Virginia May 1

Wisconsin May 15

Wyoming May 22
USDA APHIS PPQ 19

Appendix E
USDA APHIS PPQ 20

Appendix F