22. Western Bean Cutworm - Tracey Baute and Jocelyn Smith

Western Bean Cutworm
Tracey Baute and Jocelyn Smith
OMAFRA-Ridgetown, University of Guelph Ridgetown Campus

 Lepidoptera: Noctuidae
 Striacosta albicosta (Smith), Arizona, 18871, 2.
 Occurred in Colombia, Mexico, SW United States
 Outlying records: southern Idaho and Iowa
Western bean cutworm
Photo by J. Obermeyer, Purdue
1 Smith 1887, 2LaFontaine and Gill 2004

WBC Range Expansion
Grey – Original Range
Yellow – Expansion since 2000
From: Ecology and Management of the
Western Bean Cutworm (Lepidoptera:
Noctuidae) in Corn and Dry Beans J Integr
Pest Manag. 2010;1(1):A1-A10.
doi:10.1603/IPM10003

Larval Behaviour in Corn vs Beans
• WBC behave differently in corn vs. beans
• In corn, you can see all stages of the insect during
the day
– Easily find eggs on leaves or larvae in ear later in the
season
• In beans, only young larvae active during the day.
Mid to late instars active at night, moving plant to
plant each night to feed. Hide in ground during day
– Very difficult to find any life stage on the plant prior to pod
feeding/holes appearing

Pupation and Moth Emergence
• Larvae drop to the ground in fall to make pre-pupal chamber
• Stay all winter in pre-pupal stage
• Pupate in soil in May and June
• Moths begin to emerge from pupae in Ontario soils in early
July (UGRC, 2011-2013)
• Emergence occurs earlier upwind
from Ontario since traps begin to
catch moths in early June
• Emergence is staggered, given that
trap catches continue for over three
months

Migrant and Resident Populations
• Carried in via weather fronts from neighbouring
states, prior to our resident population emerging
• Resident moths also fly and get carried across
Ontario, into Quebec, NY and Atlantic provinces
(PEI and Nova Scotia confirmed in 2017)

Adult Moths
• Moths present in Ontario from June until early
September, with avg. peak flight in late July
• Females emerge first, reach sexual maturity in 4-6
days and mate approx. 3 times
• Lay 3- 400 eggs in lifespan
• Average lifespan of males and females is 7 and 9
days, respectively

Moths fly at night but
you might find them
resting in the leaf
axils during the day
MSU research found
that the bulk of
moths were flying
around between
1 am – 3 am
T. Baute, OMAFRA

J. Smith, UGRC
WBC Moth Identification
• Approximately 2 cm in length
• White band along wing margins
• Full moon and boomerang markings on each wing
• Wing folds over the other, almost lining up with each other
at the tip

Realistic
encounter with
WBC moths –
in traps
Moths lose the
scales on their
wings after a
few days in the
trap– so no
markings

Preferred Corn Stage
Dry beans
preferred, or late
planted corn
J. Smith et al. 2017

Corn Growth Stage is Key
• If there is no tassel inside the whorl, the newly
hatched larvae die within a day or two
• Eggs laid on young corn plants will die
• Focus on fields that at least have a tassel
developing inside the whorl
• Cues for adults from tassel and silk tissue?
• Variable growth stages in fields complicate
scouting

WBC Eggs
• Egg masses have an average of 50-84 eggs
• Longitudinal striations like cantaloupe
• Pearly-white when fresh
• Hatch in 5 to 7 days
(temp. dependant)
• Peak egg laying shortly
after peak flight

Assessing age of egg mass
Day 1 2 3 4 5 6 7
Pearl
white
Light
tan
PurpleDark
tan
Hatch
C. DiFonzo, MSU

Larvae
• Goes through 6 instars in approx. 30 days
• ~2 mm (1st) to ~34 mm (6th) in length
• Initially feed on their eggshell, then can only
survive on tassel, pollen (flower), silks or kernels
(pod and seeds) – little to no leaf feeding
• Not cannibalistic – can have multiple per ear
• Actively move from plant to plant

Last Instars
5th and 6th instars
T. Baute, OMAFRA
Two distinct bands
behind head

10 feet across rows
Larval dispersal
Infestations can
be spotty!

Economic injury by WBC
 Yield loss of 3.6-15 bu/ac with
one larva per plant
 Grain quality loss
 Secondary pests
 Mycotoxins
C. DiFonzo, MSU
C. DiFonzo, MSU

The pest complex
Western Bean
Cutworm
Fusarium Ear Rot/Gibberella Ear Rot
& Mycotoxins
Injury
Silk

What are Mycotoxins?
 Mycotoxins = toxic metabolites of fungi
Mycotoxin Commodity Fungal source(s) Effects of ingestion
Deoxynivalenol (DON)
(Vomitoxin)
Wheat, corn, barley
Fusarium graminearum Human toxicoses India,
China, Japan, and Korea.
Toxic to animals,
especially pigs.
Fusarium crookwellense
Fusarium culmorum
Zearalenone (ZEN) Corn, wheat F. graminearum Possible human
carcinogen (IARC). Affects
reproductive system in
female pigs.
F. culmorum
F. crookwellense
Ochratoxin A (OTA) Barley, wheat, and many
other commodities
Aspergillus ochraceus Suspected by IARC as
human carcinogen.
Carcinogenic in laboratory
animals and pigs.
Penicillium verrucosum
Fumonisin B1 Corn Fusarium moniliforme plus
several less common
species
Suspected by IARC as
human carcinogen. Toxic
to pigs and poultry. Cause
of ELEM, a fatal disease of
horses.
Aflatoxin B1, B2
Corn, peanuts, and many
other commodities
Aspergillus flavus Potent human carcinogens
by IARC. Adverse effects in
various animals, especially
chickens.
Aflatoxin B1, B2, G1, G2 Corn, peanuts Aspergillus parasiticus
http://www.fao.org/wairdocs/x5008e/x5008e01.htm

Risks associated with mycotoxins in grain
 Feed quality
 Detrimental effects on livestock
 Ethanol production
 Initial mycotoxin concentration is concentrated by 3X in DDGS
 Trade and marketing implications
 Rejection
 Downgraded grain
 Financial penalties
Mycotoxin Commodity Canada Commodity USA
Deoxynivalenol
(mg/kg=ppm)
Uncleaned soft
wheat for human
consumption
2 ppm Finished wheat products 1 ppm
Deoxynivalenol Diets for cattle &
poultry
5 ppm Grains and grain by-products
destined for ruminating beef and
feedlot cattle older than 4 months
and chickens (not exceeding
50% of the cattle or chicken total
diet)
10 ppm
Deoxynivalenol Diets for swine,
young calves, &
lactating dairy
animals
1 ppm Grains and grain by-products (not
exceeding 40% of the diet)
5 ppm
www.inspection.gc.ca/animals/feeds/regulatory-guidance/rg-8/eng/1347383943203/1347384015909?chap=1#s1c1

Deoxynivalenol (DON) in Ontario corn
 Frequent issue in Ontario grain corn
DON 2011 2012 2013 2014 2015 2016 2017
<0.5 ppm
75%
85% 84% 66% 75% 48% 69%
0.5-<2.0 ppm 11% 14% 25% 20% 26% 17%
≥2.0 ppm 24% 4% 2% 9% 5% 26% 14%
OMAFRA Survey, A. Tenuta and B. Rosser 2017
45% samples > 3ppm

The
Disease
Triangle
Host
Environment Pathogen

Fusarium in corn – Silk infection
Favourable Conditions:
Inoculum source
Optimal weather
• 24-28°C (75-82°F)
• Moisture (rain, dew, fog, humidity)
Hybrid susceptibility
Optimal infection @ Silk browning
http://extensionpublications.unl.edu/assets/html/g2181/build/g2181.htm

Insects and mycotoxins
Fall armyworm,
corn earworm
& fumonisins
Sap beetles
European corn borer
J. Obermeyer, Purdue
J. Obermeyer, Purdue P. Porter, TAMU

ECB and DON
 Bt corn reduced DON by ~60% when infested with high
intensity (>4 cm stalk tunneling) of ECB
DON (ppm)
1996 1997 1998 1999 Avg
Non-Bt isoline 1.25 0.51 1.15 1.19 0.96
Bt 0.45 0.36 0.69 1.06 0.57
P-value <0.0001 0.02 0.0019 0.51 <0.0001
Schaafsma et al. 2002 Plant Disease

Ralls, Texas, 2017.
Vip3A
“Lesser Bt” Pat Porter, TAMU

Vip3a - 6 ppm Fumonisin
“Lesser Bt” – 208 ppm Fumonisin
Ralls, Texas, 2017.
Pat Porter, TAMU

Fusarium in corn – Silk infection +
WBC

Insecticide Efficacy
 2011: 2 sites with 77 and 85% plants with WBC egg masses
 Field-scale plots (3.6 × 18 m), 4 reps, RCBD, Non-Bt or Cry1Ab corn
 Applied at early VT (~90% tassel emergence) with high-clearance
sprayer
 WBC Injury
 No significant differences
in DON or yield
Incidence 72-88%
Severity 75-95%

Insecticide Screening
Treatment WBC injury
DON
(ppm)
Yield
(bu/ac)
Rate
(g a.i. ha-1)
Incidence
(% ± SE)
Severity
(cm2 ± SE)
UTC - 57.3 ± 9.03b 1.99 ± 0.257c 1.82 ± 0.528 165.0 ± 8.3
PROLINE 200.0 56.0 ± 9.16b 1.87 ± 0.259bc 2.50 ± 0.725 168.5 ± 8.3
MATADOR 10.0 16.0 ± 5.08a 0.47 ± 0.258a 1.76 ± 0.509 157.5 ± 8.3
MATADOR 22.4 11.0 ± 3.77a 0.13 ± 0.256a 1.55 ± 0.449 159.0 ± 8.3
MATADOR + PROLINE 10.0 + 200.0 11.2 ± 3.93a 0.08 ± 0.296a 1.62 ± 0.468 174.8 ± 8.3
CORAGEN 25.0 25.7 ± 7.26ab 0.85 ± 0.259abc 1.41 ± 0.409 168.5 ± 8.3
CORAGEN 50.0 13.9 ± 4.73a 0.36 ± 0.258a 1.64 ± 0.476 177.9 ± 8.3
CORAGEN 75.0 19.8 ± 6.02ab 0.52 ± 0.258a 1.68 ± 0.487 179.5 ± 8.3
VOLIAM XPRESS 50.0 + 25.0 8.4 ± 2.89a 0.20 ± 0.258a 1.14 ± 0.330 159.0 ± 8.3
DECIS 15.0 13.9 ± 4.48ab 0.23 ± 0.257a 1.85 ± 0.535 182.7 ± 8.3
BELT 105.0 16.4 ± 5.33a 0.36 ± 0.258a 1.35 ± 0.390 177.9 ± 8.3
SUCCESS 39.8 34.5 ± 8.49ab 0.71 ± 0.258ab 1.70 ± 0.493 163.8 ± 8.3

0
1
2
3
4
5
6
100
120
140
160
180
1 2 3 4 5 6
Bu/ac
DON ppm
Application timing of prothioconazole (200 g ai/ha)
1 UTC -
2 V16-17 Silk emergence
3 Full Tassel Silking
4 Full Silking Silks fully emerged
5 Full Silking + 5 Days Silk browning
6 Full Silking + 11 Days Silk senescence
Full silking
Limay-Rios & Schaafsma 2013
Proline

Bt & pesticide efficacy
 3 sites × 3 years (2012-14)
 4 replications, large plots
 Bt: Non-Bt vs. Cry1F vs. Vip3A
 Spray treatments = insecticide and/or fungicide & application timing:
Trt Insecticide Timing Fungicide Timing
1 None - None -
2 Voliam Xpressa Early VT - -
3 Coragenb Early VT - -
4 Voliam Xpress VT/R1 Prolinec VT/R1
5 Coragen VT/R1 Proline VT/R1
6 - - Proline R1 (Full silking)
7 - - Headlined R1 (Full silking)
8 Voliam Xpress Early VT Proline R1 (Full silking)
achlorantraniliprole (50 g a.i. ha-1), bchlorantraniliprole + £-cyhalothrin (25 and 50 g a.i. ha-1), cprothiconazole (200 g a.i. ha-1),
dpyraclostrobin (100 g a.i. ha-1)
419 420
213 214
5 4
407 408
5 4
301 302
7 6
1 2
8 7
6
321 322 323 324
3 4 7
405 406
2 8
47
7 8
3
4 5 6
315 316
1 3
318
2
312
5
6 7
18
4
218215 216 217
306
7 8 2 8
303 304 305
8
42
48
224
782
409 410 411 412
421 422 423 424
401 402 403 404
2 8
413 414 416
6
415
5
418
1
417
3
B
o
r
d
e
r
B
o
r
d
e
r
45 27 11
9 3 21
3 1 2 1 5 4
23 15 35
33 39
14 20 30
26 8 6
317
1
313 314
6 5
319 320
4 3
307
2
308 309
32
310 311
5 6 3
38 44
219
24
220 221
40
222 223
1
207
10
208 209
4
210 211
22
212
3 1 2 1 5 4
34 28 12
7 6
206
2 8 3 4 7 6
201
46
202 203
16
204 205
36
118
6 5 4 5 8 7
124
8 7 8 2 4
117
41
119
37
120 121
43
122 123
17
3
107
13
108 109
7
110 111
113
25
114 115
19
116
101
1
102 103
31
104
1 2 6 7
112
4 3 1 3 1 2
106
5
5
105
29
6

 Lower incidence of WBC injury on VIP (~10%) than non-Bt and Cry1F
hybrids (~30%)
 No treatment effects
for Vip3A hybrid
 No difference between
non-Bt and Cry1F
 Non-Bt and Cry1F
 Incidence ↓ 55-75%
 Severity ↓ 82-90%
 No difference due to
tank mix or timing
% Severity of WBC injury (SE)
Treatment Timing
35F
Non-Bt/
Cry1F
P0621
Non-Bt/
Cry1F
N46U
Vip3A
UTC - 0.23 (0.142) 0.57 (0.273)c 0.03 (0.013)
VOLIAM XPRESS Early VT 0.12 (0.077) 0.05 (0.025)a 0.05 (0.021)
CORAGEN Early VT 0.17 (0.104) 0.08 (0.039)ab 0.03 (0.013)
VOLIAM XPRESS
+ PROLINE
VT/ R1 0.09 (0.057) 0.10 (0.045)ab 0.01 (0.006)
CORAGEN +
PROLINE
VT/ R1 0.16 (0.077) 0.16 (0.077)abc 0.03 (0.012)
PROLINE R1 0.18 (0.112) 0.22 (0.112)abc 0.05 (0.021)
HEADLINE R1 0.23 (0.142) 0.35 (0.164)bc 0.02 (0.010)
VOLIAM XPRESS
+ PROLINE
Early VT + R1 0.14 (0.086) 0.05 (0.023)a 0.03 (0.012)
Bt & pesticide efficacy

 Treatment effect, no Bt effect
 Observed greater reduction in DON with insecticide than fungicide
 Low DON levels, fungicide-only treatments may have been applied too
late (late R1-R2), silk infection occurred and insect injury not controlled.
 No difference in DON due to application timing of insecticide + fungicide
Effect on total DON
(p<0.05, ANOVA, Tukey-Kramer)

Grain yield
Insecticide @ VT: 0-4%
Fungicide @ R1: 2-13%
Insecticide + fungicide: 4-15%

WBC & mycotoxins
 Very complex problem
 Environment
 Hybrid susceptibility
 Hybrid offerings change
 WBC injury:
incidence>>>severity
 Difficult to forecast
 Challenging to manage, but
WBC control is important
 Costly
 Tank-mix applied $36.50/ac CAD

Trapping for WBC
• Indicate moth presence in a region
• Indicate when peak flight and peak egg laying
likely
• Trap counts do not determine if threshold has
been reached (only catching males)
• Very important for areas outside the original hot
spots to trap
• >2500 trap locations over 10 years, captured
over 858,000 WBC moths in Ontario!

0
50
100
150
200
250
300
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Average#ofWBCMothsCaptured
Week Trapped
2017 Ontario WBC Trap Catches
Week 1 - May 29 - June 4
Week 2 - June 5-11
Week 3 - June 12-18
Week 4 - June 19-25
Week 5 - June 26-July 2
Week 6 - July 3 - 9
Week 7 - July 10-16
Week 8 - July 17-23
Week 9 - July 24-30
Week 10 - July 31 - Aug 6
Week 11 - Aug 7 - 13
Week 12 - Aug 14 - 20
Week 13 - Aug 21-27
Week 14 - Aug 28 - Sept 3
Week 15 - Sept 4 - 10

0
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100
150
200
250
300
350
Week
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Average#ofMothsperTrap
Trapping Week #
Average Regional WBC Trap Catches 2017
Region 1 Region 2 Region 3 Region 4
Region 1 – Essex
Region 2 – CK, Lambton, Middlesex, Elgin, Oxford,
Haldimand/Norfolk, Brant, Huron
Region 3 – Perth, Wellington, Waterloo, Bruce,
Dufferin, Peel
Region 4 – Grey, Simcoe, Halton, Niagara, Durham,
Northumberland, Prince Edward, Lennox &
Addington, Ottawa, Prescott & Russell, Stormont,
Dundas and Glengarry
Week 1 - May 29 - June 4
Week 2 - June 5-11
Week 3 - June 12-18
Week 4 - June 19-25
Week 5 - June 26-July 2
Week 6 - July 3 - 9
Week 7 - July 10-16
Week 8 - July 17-23
Week 9 - July 24-30
Week 11 - Aug 7 - 13
Week 12 - Aug 14 - 20
Week 13 - Aug 21-27
Week 14 - Aug 28 - Sept 3
Week 15 - Sept 4 - 10

0
50
100
150
200
250
300
Week
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Week
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Week
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Average#ofWBCPerTrap
Week Trapped
Blue - Some egg laying taking
place but unless tassel present,
larvae will die. Premature to
spray. Majority of eggs still to
come during and after peak flight.
Yellow- Shortly after peak
moth flight is peak egg laying.
Target fields in the ideal
growth stage and scout for
eggs to determine threshold.
Peak flight

Scouting in Corn for WBC
• If traps are catching moths, focus on fields in the
pre-tassel to full tassel stages
• Scout 10 plants in ideal growth stage, in 10 areas of
the field (100 plants each time)
• Scout every 5 to 6 days, for at least 3 weeks
• Count the # of plants with egg masses
• Accumulate # of plants over the 3 week period
• Be area of variable growth stages in each field.
Focus scouting in the areas of the field in the ideal
stages

Walk corn rows with plants between you and the sun. Eggs leave shadows!

Chris DiFonzo
recommends a
face shield to
enable fast
walking
through corn
fields while
looking up

Adjusted WBC Corn Threshold
• Previous threshold and timing were:
– 5% of plants scouted with egg masses and/or
small larvae (decreased from 8% in Nebraska)
– spray at full tassel when majority of egg masses
have hatched

Adjusted WBC Corn Threshold
• Previous threshold and timing were:
– 5% of plants scouted with egg masses and/or small
larvae
– spray at full tassel when majority of egg masses have
hatched
• Modified threshold for Great Lakes
– cumulative 5% threshold – when 5% of the plants over
a two or three week period have had egg masses
and/or small larvae
– even lower threshold likely needed, if growing a
Fusarium susceptible hybrid

Adjusted WBC Spray Timing for Corn
• Pre-tassel to full tassel stage has been too early
– Prolonged moth flight and egg laying
• WBC only feed on tassel, silks and kernels – can’t
live on tassel tissue for long
• All WBC larvae will head to the ear when present
• Instead, spray when fresh silks are present,
targeting the ear zone (ground application only?)
• Can tankmix with fungicide for ear mould
protection at the same time

Products Registered on Corn in Canada
• Matador or Silencer (pyrethroid)
• 83 – 187 mL/ha
• 14 days pre-harvest interval silage, 21 days for field corn
• Coragen (diamide)
• 250 – 375 mL/ha
• 14 day pre-harvest interval
• Delegate (spinosyns)
• 120 – 210 grams/ha
• 28 days pre-harvest for stover, 14 days for forage
• Voliam Xpress (pyrethroid + diamide)
• 500 mL/ha
• 7 days pre-harvest interval
• ROTATE chemistries – high risk of resistance with WBC

Transgenic Corn Options
• Cry 1F (Herculex or SmartStax) no longer
provides protection against WBC
• Only hybrids with Vip3A (Viptera) provides
control

Evidence for resistance of Western bean
cutworm to Cry1F Bacillus thuringiensis
protein and transgenic corn hybrids in
Ontario, Canada
J. L. Smith1, M. D. Lepping2, D. M. Rule2, Y. Farhan1, and A. W. Schaafsma1
1 Department of Plant Agriculture, Ridgetown Campus, University of Guelph, 120 Main
St. E., Ridgetown ON, Canada N0P 2C0.
2 Dow AgroSciences LLC, 9330 Zionsville Rd. Indianapolis, IN 46268

SMALL PLOT TRIALS (2011-2014)
Year Trmt Plants infested
(% ± se)
Kernel damage
(% ± se)
Yield
(T/ha ± se)
Egg masses Larvae (R3) Incidence Severity
2011 Non-Bt 1.2 (0.52) 11.1 (4.01) 88.9 (3.16)b 3.1 (0.31)b 10.1 (1.15)
SSX 1.0 (0.47) 10.2 (3.80 54.5 (5.45)a 1.4 (0.19)a 10.6 (1.15)
2012 Non-Bt 2.9 (1.08) 75.0 (2.85) 85.5 (7.95) 5.3 (0.63) 10.2 (1.93)
SSX 5.6 (1.60) 67.7 (3.03) 84.5 (8.18) 6.2 (0.68) 9.5 (1.93)
2013 Non-Bt 3.4 (0.57) 71.9 (6.50) 100.0 5.3 (0.69) 6.6 (1.08)
SSX 4.2 (0.63) 52.9 (7.25) 100.0 7.9 (0.53) 7.3 (1.08)
2014 Non-Bt 16.0 (1.82) 35.6 (8.91)b 47.9 (7.55) 2.4 (0.45) 6.3 (0.47)
SSX 19.9 (2.13) 6.1 (3.69)a 50.0 (7.56) 2.5 (0.46) 6.6 (0.47)
SSX RA 23.1 (2.35) 12.3 (5.30)a 56.3 (7.50) 2.7 (0.50) 6.1 (0.47)

Cry1F susceptibility bioassays
 Adults collected at black light traps or egg masses from the field
in late July 2015
 5 locations in SW ON
 Dose-response diet-overlay bioassay
(Marcon et al. 1999, Dyer et al. 2013)
 Truncated Cry1F (53% a.i.) from Dow AgroSciences
 Infested with neonates, 24 larvae/conc/rep x 3 reps
 F0: 0 to 30,000 ng ai cm-2
 Mortality at 7 and 14 d
 Weight of surviving larvae at 14 d
 F1: 0 to 75,000 ng ai cm-2
 Mortality and weight at 7 d

WBC and Cry1F
Collection n LC50 (95% CL) 7 d (ng Cry1F/cm2)
Bothwell F0 360 13,032 (6,694-20,093)
Ridgetown F0 360 21,197 (12,828-56,660)
Dresden F0 360 .a
Springford F0 360 11,639 (5,578-19,534)
Melbourne F0 360 .a
Ridgetown F1 357 72,107 (35,988-39,441,298)
Springford F1 480 28,926 (8,487-77,062)
a Estimate exceeds the highest concentration tested.

European corn borer and Cry1F
Collection n LC50
2 (95% CI) LC95
2 (95% CI) LC99
2 (95% CI)
2016 (ng Cry1F/cm2)
Winger (control) 648 4.74 (3.99-5.48)a 16.82 (13.90-21.73)a 28.41 (21.95-40.83)a
Oxford 648 4.54 (3.93-5.13)a 12.57 (10.68-15.70)a 19.17 (15.40-26.18)a
Simcoe 648 4.70 (4.09-5.33)a 15.73 (13.16-19.89)a 25.94 (20.43-35.89)a
Niagara 648 4.53 (3.90-5.17)a 14.46 (12.11-18.31)a 23.38 (18.44-32.52)a
Manitoba 648 5.44 (4.62-6.24)a 18.50 (15.36-23.78)a 30.72 (23.87-43.84)a
= High Dose

2016, southcentral MI
WBC infested Cry1F fields

John Obermeyer, IPM Specialist, Purdue University
“No western bean cutworm control in this Cry1F-expressing corn”

Dr. Andy Michel, Ohio State: “Just plain ugly”

Resistance management for WBC
Challenges:
• Reliance on 1-2 insecticides
• Slow integration of Vip3A into widely used hybrids
• Vip3A deployed with a 5% integrated refuge
• Almost no effective refuge due to cross-pollination
• Extensive inter- and intra-plant larval movement
• Exposure of later instars to sublethal doses
Solutions(?)
• More insecticide options needed
• Tank-mixes, rotation program
• Stewardship of Vip3A
• Abandon integrated refuge
• Require insecticide treatment
• More high-dose transgenic solutions

Bt pollen flows to “refuge” ears
Pat Porter, TAMU

WBC Resources
• Field Crop News – up to date, in-season activity
• WBC Trap Network – www.cornpest.ca
– Interactive Maps
– Trapping Instructions
– Infosheets for Dry Beans and Corn
• Twitter @TraceyBaute, @JocelynLSmith,
@JenniferBruggem and @MegnMoran
• Pest Manager App
• Agronomy Guide, OMAFRA Pub 811 and Field Crop
Protection Guide, OMAFRA Pub 812

Thanks to Our Research Collaborators and
Sponsors Over the Years

22. Western Bean Cutworm - Tracey Baute and Jocelyn Smith

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22. Western Bean Cutworm - Tracey Baute and Jocelyn Smith