United States Department of Agriculture

Questions and Answers:

USDA’s 2018 Emerald Ash Borer Survey

Animal and Plant Health Inspection Service 

Plant Protection and Quarantine

What is the 2018 Emerald Ash Borer Survey?

The U.S. Department of Agriculture’s (USDA) 2018

Emerald Ash Borer (EAB) Survey will rely on the 

purple prism detection tool, or “trap,” to monitor 

known EAB infestations and locate other unknown 

EAB populations. The national survey will set about 

12,000 traps in a 100 mile buffer along the leading 

edge of the quarantine which borders these 16

States: Alabama, Arkansas, Colorado, Florida, 

Kansas, Louisiana, Maine, Minnesota, Mississippi, 

Nebraska, New Hampshire, Oklahoma, Rhode 

Island, South Dakota, Tennessee, and Vermont.

Texas will conduct an independent EAB survey.

The survey strategy continues to use a computergenerated, risk-based sample design, along with 

historical program data and regulatory knowledge. 

This design enables USDA to monitor the leading edge 

of EAB infestations, determine whether undetected 

pockets of infestation are present, and identify locations 

best suited for biological control releases.

What do the EAB detection traps look like?

The purple trap is a three-dimensional triangle or prism. 

It’s made out of thin, corrugated purple plastic that has 

been coated with non-toxic glue on all three exterior 

sides. The purple traps are about 24 inches long and 

hang vertically in ash trees. Each trap is baited with a 

lure on the interior to attract EAB to it.

For trap images, go to www.aphis.usda.gov/plant-health/

eab. Scroll down to the “Pest Management” section and 

click on “2018 Emerald Ash Borer Survey Guidelines.”

Who is involved in the 2018 EAB Survey?

The EAB survey is a collaboration involving USDA’s 

Animal and Plant Health Inspection Service (APHIS), 

State departments of agriculture or natural resources, 

Tribal cooperators, and the USDA survey contractor.

Who is paying for the 2018 EAB Survey?

The EAB survey is funded by USDA. If a State surveys

for EAB on its own, USDA will provide survey supplies.

Why do you call the detection tools “traps?” Do they 

really trap EAB?

We refer to the detection tools as “traps” out of 

convenience. The detection tools do not catch beetles 

as a way to reduce or deplete populations. They simply 

help us detect new infestations and monitor the spread 

of the beetle. Through ongoing trap design research, 

we are continually improving our ability to locate EAB 

infestations.

Why is the color purple significant, and what is the 

lure?

In the insect world, color frequently plays an important 

role, and EAB is no exception. In 2003, researchers 

began investigating EAB responses to different stimuli 

in an effort to develop an effective detection tool.

Researchers discovered that EAB is attracted to a 

specific shade of purple—the purple trap color replicates
this shade to attract the pest. Additionally, the traps are 

baited with a lure, using a chemical called (Z)-3-hexanol, 

that mimics a chemical signal that is emitted by ash 

trees and also attracts the beetle.

How do the traps work?

In their adult stage, EABs fly around ash trees, feeding 

on leaves and looking for a mate. If an EAB lands on a 

purple trap, it will get stuck in the non-toxic glue. Survey 

crews service the traps two times: in mid- summer, to 

replace the lure and collect any suspect beetles stuck on 

them; and in the fall, to collect any suspects and remove 

the traps.

Why are the traps placed only in ash trees?

Ash trees (Fraxinus spp.) and a close relative of ash, 

the white fringetree (Chionanthus virginicus), are the 

only known host species for EAB on the North American 

continent. The lifecycle of EAB depends on the ash tree; 

the adults feed on the leaves and lay eggs in its bark 

crevices, and the larvae develop under its bark. As a 

result, EAB is drawn to ash trees. All 16 native species 

of ash—including green, white, and black ash—are EAB 

hosts. White fringetrees, however, are too small to place 

traps in and are only a minor host for the pest.

How long will the survey take to complete?

The traps will be placed in ash trees this spring and 

early summer before EAB adults emerge. The traps 

will be monitored and remain in place throughout the 

summer during the beetles’ flight season. This fall, all 

traps will be removed.

If EAB is not known to be in my State, will the traps

attract EAB and draw the beetles to my State?

No, the traps do not pull beetles into an area. The traps 

are a detection tool to help determine if EAB is already 

in the area.

What happens when an EAB is found stuck on a 

purple trap?

The insect is collected from the trap and is cleaned and 

sent to a USDA insect identifier for verification. We then 

communicate verifications of EAB to the appropriate 

State officials.

If a trap is in my area, does that mean EAB is there?

No. A trap located in your community does not mean 

EAB is present, it just means we are looking for the 

beetle. The goal of the 2018 EAB Survey is to define 

the outer boundaries of infested areas, locate new 

EAB infestations, and identify locations best suited for 

biological control (stingless wasp) releases.

What were the results of the 2017 EAB Survey?

The 2017 survey resulted in the detection of EAB in 

100 new counties. The new county detections inside

the Federal quarantine occurred in Arkansas, Illinois, 

Indiana, Iowa, Kentucky, Maryland, Massachusetts, 

Missouri, New Jersey, New York, North Carolina, 

Pennsylvania, Virginia, and West Virginia. The new 

county detections outside the Federal quarantine 

occurred in Alabama, Kansas, Louisiana, New 

Hampshire, South Carolina, and Wisconsin.

Of these 100 new county detections, 17 resulted from 

using a purple trap, 8 resulted from the green funnel 

trap, and the remaining 75 detections resulted from an 

alert citizen or State partner spotting and reporting 

signs of EAB damage.

The 2017 survey activities continued to elevate public 

awareness about the EAB program. Survey personnel 

setting and monitoring the traps in cities and towns 

created opportunities for discussion. The highly visible 

traps stimulated public interest and garnered media 

attention. As a result of the new detections, Federal 

and State EAB quarantines were expanded or 

established to help prevent the human-assisted spread 

of EAB.

In addition, the 2017 EAB survey results gave data 

to support biological control management and direct 

field personnel to appropriate locations for parasitoid

(stingless wasp) releases. Survey activities also allowed 

the EAB program to monitor the outer boundaries of 

infested areas. This information helped guide decisions 

on trap placement for the 2018 EAB survey.

What determines where a trap is set?

The 2018 EAB Survey uses a computer model to 

generate a risk-based sampling design survey that 

identifies optimal locations to survey for EAB within a

100 mile buffer area. The model analyzes a collection 

of environmental variables (e.g., soil moisture, land 

elevation, terrain) and EAB program variables (e.g., 

historical EAB survey data, targeted high-risk areas, 

pest pathways, scientific literature). The end product is 

a grid map that identifies locations where the likelihood 

of detecting EAB is greatest

More information is available in the 2018 EAB Survey 

Guidelines document. To download a copy, go to www.

aphis.usda.gov/plant-health/eab and click on “2018

EAB Survey Guidelines” under the “Pest Management” 

section.
What are the benefits of the risk-based survey

sampling design?

The risk-based sampling design is objective, transparent, 

and science-based. It preselects geographic locations to 

deploy EAB traps where there is the highest likelihood of 

detecting EAB. The expected benefits of the 2018 EAB 

survey include:

 To increase the number of successful EAB detections 

outside the known infested area

 To improve the capability of detecting EAB close to 

the date of a new attack

 To find locations that are best suited to implement 

biological controls

Will traps be set in areas not selected by the model?

Yes, some traps will be set in discretionary locations 

based on local conditions, regarding terrain, and ash 

tree availability.

Are the traps safe?

The traps pose no risk to people or pets, however 

they are covered with non-toxic glue and can be

extremely sticky if touched. The traps will be in ash trees 

throughout the summer—please do not disturb them. If 

you see a trap on the ground, please call toll-free USDA 

EAB hotline at 1-866-322-4512 to report it. If you call 

outside of regular business hours, leave your name, 

telephone number, State, and location of the fallen trap.

What can I do to support the 2018 EAB Survey 

program?

Please talk to your family and friends about the EAB 

survey to raise awareness. If you see one of the traps 

on the ground or damaged, call the toll-free USDAEAB 

hotline at 1-866-322-4512. Please become familiar 

with the signs and symptoms of an EAB infestation and 

inspect your own trees. Lastly, don’t move firewood; a 

prudent alternative is to only purchase USDA- or Statecertified, treated, and labeled firewood. The public

contributes significantly to the quality of the EAB survey 

and the overall program. We value your efforts and 

appreciate your support.

Issued February 2018

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