Emerald Ash Borer Detection Efforts: From Girdled Trees to Purple Traps

Emerald Ash Borer Detection

Efforts: From Girdled

Trees to Purple Traps

Therese M. Poland, Deborah G. McCullough,

Deepa Pureswaran, Cesar Rodriguez, Andrea Anulewicz, and David Cappaert

The Problem

• Early detection & delimitation are virtually impossible

• Signs and symptoms do not appear for 1+ years after attack

• By then adults may have spread

• New tools for detection are desperately needed!

Trap Tree Studies

Year # Field Sites

# Reps Treatments

2003 3 18 Healthy, Girdled, Herbicide, Trap logs

2004 3 24 Healthy, Girdled, Herbicide, Wounded,

2005 4 20 Healthy, Girdled, Herbicide, Methyl jasmonate (MJ)

2006 4 40 Healthy, Girdled, MJ, Manuka oil,

2007 4 20 Healthy, Girdled, Wounded, 2-year Girdled

3 Sites (6 reps/trt/site)Healthy ashGirdled ash Hypo-hatchet + herbicide ash6 ft trap logs: green, white, black ash

2003 Trap Tree Study

Mean Number of EAB Captured at 3 Sites (N = 18)

0

10

20

30

40

50

60

Girdled Tree HerbicideTree

Control Tree Green AshLog

White AshLog

Black AshLog

a

b

b b

b

b

2003 Results

Is it the wound itself or stress causedby girdling that increases attraction?

Treatment Wound Stress

Control X X

Herbicide X

Vertical wound X

Horizontal girdle


2004 Results

EAB Larval Density Per m2 (N=24)

0

10

20

30

40

50

60

Control Herbicide Girdle Wound

b bb

a

Mean Number of EAB Captured at 3 Sites (N = 24)

02468

1012

Control Herbicide Girdle W ound

b

ab

aab

2005 Trap Tree StudyStress Agents and Trap Height

1.Girdled

2.Healthy

3.Herbicide

4.Methyl Jasmonate (stress hormone)

4 sites, 18 replicates totalHalf in open sitesHalf in closed canopy

Girdled – open Girdled - closed


Herbicide – open Herbicide - closed


MeJA dispenser

Low band

Girdle

High bandPurple panel


Methyl-Jasmonatebubble capsstrungin canopy

10 per tree


0

5

10

15

20

25

30

35

Control Girdle Herbicide MeJa

Mea

n #

EAB

per

tree

c

a

abbc

Larval Density (N=20)

0

20

40

60

80

100

120

Control MJ Herbicide Girdle

b b b

a

Mean number of EAB, 4 sites (N=20)

2005 Results

0

5

10

15

20

25

30

35

40

Control Girdle Herbicide MeJa

me

an

# E

AB

pe

r tr

ee

Low

High

Trap

2005 ResultsMean Number of EAB per Tree

by Trap Type

0

5

10

15

20

25

30

35

open dominant partlyopen

partlyclosed

closed

Me

an

EA

B p

er

tre

e

ab

a

ab ab

b

2005

Open-grown trees are more attractive to EAB

2005 Results

40 Replicates of 4 treatments at 4 sites:

• Control untreated ash trees• Girdled ash trees• Ash trees with 6 Manuka oil clusters on

trunk• Ash trees exposed to 20 MeJA bubble

caps in canopy


Larval Density (N=20)

0

40

80

120

160

200

Control Girdle Manuka Meth Jas

b

a

b b

0

10

20

30

40

C Girdle Manuka Meth Jas

b

a

bb

Mean Number of EAB, 4 Sites (N=40)

2006 Results

0

5

10

15

20

25

30

35

40

45

open dominant partly open partly closed closed

a

ab

ab

b

b

2006

2006 Results

Open-grown trees are more attractive to EAB

Trap Tree Studies Conclusions• 5 years , 122 replicates• 14 field sites (variable EAB populations & tree

shading)• Girdled trees consistently the best treatment• Girdled trees captured significantly more EAB

than healthy trees (approx. 10x) at low density sites

• Larval densities were significantly higher in girdled than healthy trees

• Low sticky bands caught as many or more EAB as high bands or traps in the canopy

• Open-grown trees catch more EAB

Analysis of Ash Volatiles to Identify Attractants for EAB

Volatile Collection

• Insect feeding damage 10 EAB in screen cages for 5 days

• Methyl Jasmonate (MeJA) stress hormone spray 50ml of 0.03% solution

• Mechanical damage 20% of leaf area removed with scissors

• Healthy control

Insect Damage

Methyl Jasmonate

Control

Retention Time (min)

Z-3hexenylacetate

E-B-ocimenelinalool nonatriene

indolizine

E,E-a-farnesene

Qu

anti

ty o

f vo

lati

le (

ng

/g/h

+ S

E)

Control

Insect Damage

MeJA

0

200

400

Compound Number1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Z3-hexenyl acetate

Eb-ocimene

linaloolnonatriene

E2-hexenal

Z3-hexenol

3-Methylbutyl-aldoxime

2-methylbutyl-aldoxime

indole

E,E-a-farnesene

Z-jasmone

FID

GC-EAD

hexenal

hexenol Z3-hexenolZ3methylbutylaldoxime

E2methylbutyl-aldoxime Z3-hexenyl-

acetate

Eb-ocimene

linalool

nonatrieneE,E-a-farnesene

EAB Antennal Responses

0

1

2

3

4

5

Control 20ug 200ug 2mg 20mg

0

1

2

3

4

5


EA

G A

mplit

ude (

mV

± S

EM

)

(Z)-3-hexen-1-yl acetate

3-Methyl-butylaldoxime

0

1

2

3

4

5


0

1

2

3

4

5


0

1

2

3

4

5


Hexenal (E)-2-hexenal

(Z)-3-hexen-1-ol

MalesFemales

**

*

**

**

**

**

***

*

0

1

2

3

4

5


2-Methyl-butylaldoxime **

*

Cartridge Dosage

EAB Antennal Dose Response Profiles

0

1

2

3

4

5


0

1

2

3

4

5


0

1

2

3

4

5


0

1

2

3

4

5


0

1

2

3

4

5


Cartridge Dosage

E,E--farnesene

(E)--ocimene

Linalool Indole

(Z)-jasmone

Hexyl acetate

**

***

0

1

2

3

4

5


EA

G A

mplit

ude (

mV

± S

EM

)Males

Females

EAB Antennal Dose Response Profiles

(Z)-jasmone

100 75 50 25 0 25 50 75 100

Clean Air

Clean Air Treatment

Insect Damage

MeJA

Healthy

N % No Choice

52

38

32

41

57

30

77

55.7

23.6

21.8

29.3

44.0

26.7

36.4

*

*

n.s.

n.s.

n.s.

n.s.

n.s.

Percent Response

Attraction of EAB to Stressed or HealthyAsh Seedlings in Olfactometer Bioassay

Field Trapping Studies

EAB attraction to GLV alcohols

0

5

10

15

20

all t2hex +c3hex

hex + c3hex hex + t2hex blank

Males

Females

aab ab

b

b

EAB attraction to GLV aldehydes

0

5

10

15

20

25

30

all t2hex + non hex + non hex + t2hex blank

Males

Females

A Multi-Component Trap for EAB

Top panel baited with Leaf Blend

Bottom panel baited with Bark Blend

Overall Visual Silhouette

• 10’ tall pole simulates tree bole

• Panels simulate tree crown

• Purple color is attractive to EAB

• Traps in sunny open locations

• Highly apparent placement may reduce competition between trap & nearby ash trees

• Can install traps along roadsides, in open areas or just outside forested area

• Logistically simple & efficient to monitor

Experimental Design - 2006

6 Field Sites40 Replicates (5-10 per site)

4 Treatments:

• Leaf Blend + Bark Blend + Texture• Leaf Blend + Texture• Bark Blend + Texture• Leaf Blend + Bark Blend

Trapping Results - 2006• Captured 4,060 EAB

• Leaving off Leaf Blend reduced attraction

• Leaving off Bark Blend or Texture did not reduce attraction

0

5

10

15

20

25

30

35

Leaf + Bark+ Texture

Leaf +Texture

Bark +Texture

Leaf + Bark

abab

b

a

Experimental Design - 2007

8 sites: moderate to very low EAB densities: forest edge, roadside, open field

2 - 7 blocks per site, 31 traps per treatment

5 Treatments:• DD: no lures• DD: Leaf + Manuka• DD: Leaf + Manuka + Extracts• Tower: Leaf + Bark + Extracts• Single: Leaf + Bark + Extracts

Kellogg Forest – EAB Detection Site

xx Girdled treesA

sh pla

nta

tion

Conifers

EAB not known to be present

4 EAB caught on DD-L+M trap 28 Jun, 11 July, 17 July

No EAB adults or larvae on 2 girdled trees ≈ 150 m away

Conclusions

• Girdled trees are consistently the most attractive trap trees

• Girdled trap trees and purple traps can catch EAB at low-density sites and can detect new infestations

• Purple traps are more attractive than green traps

• Baited traps are more attractive than unbaited traps

• Large silhouette traps at the ground are at least as attractive or more attractive than canopy traps

• Double decker traps are more attractive than single panel or tower traps

Using traps operationally - Issues to consider…• Pestick was re-applied after heavy rain(s).

• Traps need to be checked fairly often (e.g. 2 wk intervals?) or beetles may fall off.

• Accumulation of flies (esp. green traps) or other insects may require panel to be scraped & Pestick re-applied.

Acknowledgements

MSU: Kaeli Chambers, Tara Dell, Erin Burkett, Chenin Limbach, Bob McDonald, Ben Schmidt, James Wieferich

US Forest Service: Stephen Burr, Alison Wroblewski, Tina Kuhn, Toby Petrice

Funding: USDA Forest Service MSU’s Project GREEEN

Documents

Emerald Ash Borer Detection Efforts: From Girdled Trees to Purple Traps