The economic and environmental impact of an IPM program on hazelnuts in Oregon

12 Pages·2000·5.6 MB·English

by  R A Progar

J.ENTOMOL,SOC,BRIT.COLUMBIA97,DECEMBER2000 7
The economic and environmental impact of an IPM program
on hazelnuts in Oregon
^ R.A. PROGAR, M.T. ALINIAZEE AND J.L. OLSEN
OREGON STATE UNIVERSITY, CORVALLIS, OR97331-2907, USA
ABSTRACT
An integrated pest management (IPM) program based on monitoring, parasite releases,
andeconomicthresholdswasimplemented inthehazelnutindustryintheearly 1980's.To
assess the economic and environmental benefits of the IPM program, growers were
surveyed in 1981 to determine insecticide use in 1980, prior to the inception of the
program, and in 1998 to quantify insecticide use in 1997, after the program had been
adoptedthroughoutthegrowingregion. Surveyrespondentsencompassed23%and20%
ofthe hazelnut producing acreage in 1980 and 1997 respectively. Data indicatethatthe
total number ofannual spray applications was reduced by about 50%, resulting in an
annual industry savings ofovera half-million dollars.
Keywords: IPMefficacy,pesticideusepattern,environmental impact,economic impact
INTRODUCTION
Integratedpestmanagementutilizesalternatestrategiesinmakingpestcontroldecisionsby
emphasizingincreased informationandbyintegratingcultural,biologicalandchemicalcontrol
methods. Itoftenresults inenvironmentalbenefitsthroughthedecreased useofpesticidesand
associated reduction ofenvironmental contamination. There are numerous examples ofthe
development of IPM programs (Trumble et a/. 1997), and many studies that evaluate the
economicbenefitsofIPM programs(TrumbleandAlvarado-Rodriguez 1993; Trumble etal.
1994; White and Wetzstein 1995; Headley and Hoy 1986), yet few document both the
economicandenvironmentalsavingsthatresultfi-omasuccessfial IPMprogramonaregional
scale. Concerns over the impact of pesticide residues on food and in the environment
(Pimenteletal. 1993)arecausingindustry-wideregulationofinsecticideuseandchangingthe
wayexposureto insecticides isassessedintheenvironmentassetforth intheUSEPA'sFood
Quality Protection Act of 1996. These concerns are causing the reduction or elimination of
insecticides and changing our perspective of IPM ft-om spray-based management to an
ecosystem perspective by focusing on predators and parasitoids, and alternative methods of
pest control.
Economics and insecticide use patterns are fundamental to IPM practices and should be
usedtomeasureprogramsuccess. Studiessuggestthat it isconceivabletoreducepesticideuse
in the US by 35-50% without a significant loss of crop yield (Office of Technology
Assessment 1979; National Academy of Sciences 1989). In our study, we summarize the
reduction in insecticide use and economic impact ofa program to control the major insect
pests ofhazelnuts {Corylus avellana L.).
The listofinsects and mites associatedwith hazelnuttrees is long, representingalmostall
ofthemajorinsectandmitegroups. InOregon, over 150specieshavebeen foundonhazelnut
^Correspondence to: Robert Progar, FHP USDA FS 1249 S. Vinnell Way, Suite 200,
Boise, ID 83709 Phone: [phone] Fax: [phone] email:[email protected]
8 J. ENTOMOL,SOC.BRIT.COLUMBIA97,DECEMBER2000
trees; mostareharmless, overhalfare beneficial, onlytwo-dozen orso species are injurious,
and ofthose only six or so are considered importantpests (AliNiazee 1998). Although there
arenumerouspotential insectandmitepestsonhazelnutsinOregon,onlyfourhavewarranted
consistentinsecticideapplication(AliNiazee 1994). Itshouldbenotedthatpestincidenceand
importance change with time and orchard management practices.
Priortothe development ofan integrated pestmanagementprogram, insecticide usewas
widespread. Thispracticeresultedinresistancebythefilbertaphid,Myzocalliscoryli(Goetze)
(Homoptera: Aphidae)reoccurringevery 1 or2years(AliNiazeeandMessing 1995; Katundu
and AliNiazee 1990), outbreaks ofsecondary pests, and rapid resurgence ofprimary pests.
These outbreaks required repeated application of insecticides that further aggravated pest
conditions. As aresult, bythe early 1970's, as many as five different insecticide applications
were applied each season to control hazelnut insect pests (AliNiazee 1977).
Research conducted during the 1970's led to the formation of an integrated pest
managementprogramonhazelnutsinOregon(AliNiazee 1977). In 1982,theUSDAfundeda
4-yearprojecttodevelopanIPMprogram inOregonhazebiutorchards.Thisprogramentailed
theestablishmentofeconomic injurylevelsforhazelnutpests(Fisher 1984;Calkinetal. 1984;
Calkin and Fisher 1985), and design and implementation of a scouting and monitoring
programwhichremains inusebyhazelnutgrowers(Olsen etal. 2000). Theseeffortsresulted
in establishing levels of tolerance (1%) and economic damage for the primary pest of
hazelnuts,thefilbertworm, andinitiatedpheromonetrappingasaviablemethodofmonitoring
populations andtimingsprayapplications. Before IPM, lighttrappingwas usedtodetermine
adult emergence and time of spray application. However, there were no existing ways to
measurepopulation levels,thereforesprayswereappliedbasedonthepresenceoffilbertworm
moths intrapcatches. Inaddition, sprayswereappliedtocontrol otherperceived insectpests
basedontheirpresenceorsimplybythecalendarbecausetherewerenoestablishedeconomic
levels ofconcern. Lackofknowledgeofapest's status stronglycontributedtotheoveruse of
insecticides on hazelnuts. As a direct result ofthe IPM program growers monitor their own
orchards oremploy field scoutsto assess population levels. This level ofcurrent information
enables growers to determine the need, timing and location ofspray applications.
Concurrent with the establishment ofthe IPM program, a parasitic wasp (Messing and
AliNiazee 1989) was released as abiological control ofthe filbert aphid. The success ofthis
classical biological control program aided in the implementation of the IPM program in
thel980's (AliNiazee 1991; AliNiazee and Messing 1995), and nearly eliminated all
insecticide sprays applied against aphids. By allowing early-season beneficial insects to
becomeestablished italsohas indirectlyreducedtheapplicationofinsecticidesonotherinsect
pests in hazelnut orchards.
Inthispaperwepresentdatafi*omasurveyofhazelnutgrowersconducted in 1981 priorto
the inceptionofan IPMprogramonhazelnuts, andcontrast itwith datafi-omasimilarsurvey
conducted in 1998, afteradoption oftheprogrambyhazelnutgrowers. Ourobjectives inthis
study were to evaluate the economic and environmental impacts ofan industry-wide IPM
program to control the primary hazelnut insect pests.
METHODS
A survey of hazelnut growers was conducted in 1981 to assess grower pesticide use
patternsin 1980, i.e.,priortothe initiationofan IPM program in hazelnutorchards inOregon
(Progar and AliNiazee 1999). In 1998, a similar survey of Oregon hazelnut growers was
conductedtodeterminechanges in insecticideusepatternsresultingfromadoptionofhazelnut
IPM (i.e., in 1997). The numberofhazelnutgrowers in Oregon hasdeclinedfrom over 1,000
to about 800, whilethetotal areahas increased, indicatingatrend toward largerorchard size
J.ENTOMOL,SOC.BRIT.COLUMBIA97.DECEMBER2000 9
or grower-managed area (Rowley 1997). Table 1 summarizes the hazelnut area for each
survey. The surveys represent 23.5% (171 responses) and 20% (80 responses) of total
hazelnut-bearingarea in 1980and 1997, respectively. All insecticidequantitiesareexpressed
in kg ofactive ingredient (a.i.) because not all growers use the same pesticide formulations.
Table 1
Survey summary data ofhazelnut orchard area in Oregon.
1980 1997
Number ofgrowers 1,063 826
Total hazelnut hectares 10,316 12,121
Bearing hectares 8,741 11,412
Non-bearing hectares 1,574 708
Hectares represented in the survey 2,383 2,501
Bearing hectares (survey) 2,058 2,291
Non-bearing hectares (survey) 325 210
%
total hectares represented by the survey 23.50 20.07
TheU.S. BureauofLaborStatisticsConsumerPriceIndex(CPI)regional index(Bureauof
Labor Statistics Data 1998) was used to compare pest control costs between 1980 and 1997.
The 1980 indexvalueof247 wascompared withthe 1997 indexvalueof469toexpress 1980
dollars in 1997 values.
Costs fordifferentpesticides increaseddisproportionately, e.g., akgofSevin®(carbaryl)
increased incostby56%from 1980to 1997; whereasGuthion®(azinphos-methyl) increased
in cost by 157%). Many ofthe insecticides used in 1980 were no longer registered for use on
hazelnuts in 1997, and newer, more efficient compounds were used in 1997 that were not
available in 1980. Therefore, directcomparison ofcosts associatedwith specific insecticides
cannot be made, however total pesticide costs can be compared. The cost to apply an
insecticidetreatmentto ahectare ofhazelnuts has increased fi"om $20.34 (unadjusted dollars
US) in 1980 to $50.06 (Seavert and Olsen 1999) in 1997.
RESULTS AND DISCUSSION
Filbertworm, Cydia latiferreana Walsingham (Lepidoptera: Tortricidae)
Filbertworm is the primary insect pest in hazelnut orchards. Because there is an industry
standard ofless than a 1% tolerance for filbertworm infestation, the percentage ofhazelnut
orchard area treated remains about the same before and after the IPM program (Table 2).
However,thecompositionofthe insecticidesusedtocontrol filbertworm haschangedandthe
amount ofinsecticide active ingredient (a.i.) has declined dramatically (Table 3).
- Table 2
Primary pests in Oregon hazelnut orchards and percent ofgrowers and orchard area using
insecticides to control them.
% growers %ha % growers %ha
Pest (1980) (1980) (1997) (1997)
Filbertworm 88.2 95.8 87.5 94.0
Filbert leafi-oller 38.1 57.1 16.2 28.6
Obliquebanded leafi-oller 5.9 6.4 2.5 2.5
Filbert aphid 48.8 69.0 5.0 6.3
^
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In 1980, an estimated 39,916 kg (a.i.) ofinsecticides were applied to control filbertworm
onapproximately96%ofthehazelnutorchardareaby 88%ofthegrowers(Tables2and3). In
1997, only an estimated 1,453 kg ofinsecticide (a.i.) were applied to control filbertworm by
87% of the growers on 94% of the hazelnut area, indicating higher efficiencies and
effectiveness of insecticide application. The most common insecticide used in 1997 was
Asana® (esfenvalerate, a pyrethroid), with a small fraction ofGuthion® (azinophos-methyl)
andLorsban®(chlorpyrifos)(Table3). Asana®wasapplied inamounts 10to20-fold lessa.i.
because itwas more effective than insecticides applied 16 years earlierand can be applied in
smaller amounts. Although the same portion ofgrowers are treating the same percentage of
area for filbertworm in 1997 as in 1980, the change from organophosphates (OP) and
carbamateto esfenvalerate resulted in a large decline in the amountofinsecticide a.i. applied
andan enormousbenefittothe environment. Onlyanestimated 5%ofthegrowers usedOP's
on 0.21%ofthehazelnutareain 1997asopposedtoanestimated24%ofthegrowerson27%
ofthe area in 1980 (Table 3).
There is currently an effective IPM system in place in commercial hazelnut orchards that
incorporates an online degree-day model, and scoutingand monitoring foradult filbertworm
moths. Thedecrease intotal pesticideusemaybeattributedtomoreefficientmonitoringwith
pheromone trapping rather than the previous method of light-trapping, better timing and
targeting of insecticide applications, more efficient spray equipment, and the shift from
carbamate and organo-phosphate insecticides to synthetic pyrethroids.
Althoughthe quantity ofinsecticide used to control filbertworm declined by an estimated
38,463 kg (a.i.) fi-om 1980 to 1997, the estimated cost ofcontrol was $1,275,832 in 1997 vs.
$1,066,658 in 1980 (converted to 1997 dollars), a 20% increase in expense to control
filbertwonn (Table 7).
Filbert Leafroller (European Leafroller),Archipsrosanns (L.) (Lepidoptera: Tortricidae)
In 1980, anestimated 10,440kg(a.i.)ofinsecticidewereappliedby38%ofthegrowerson
57% ofthe hazelnut area to control filbert leafroller (Tables 2 and 4). In 1997, 2,998 kg of
insecticide (a.i.) were applied by 16%ofthe growers on 29% ofthe hazelnutarea. Lorsban®
was the primary insecticide applied followed by a small percentage ofGuthion®. The area
treated in 1997 was about halfthat of 1980 and less than a third the amount ofpesticide a.i.
was used to control leafi"oller, resulting in an estimated annual reduction of 7,445 kg of
insecticide a.i. duringthe 16-year period (Table 4).
The adoption of an IPM program on hazelnuts has significantly reduced the use of
insecticidestocontrol filbert leafroller. Theemergenceoffilbertleafrollerisnowpredictedby
degree-day modeling, and there are more accurate methods ofmonitoring to assess levels of
economic injury. Alsoofimportancearesecondaryeffectsattributedtotheeffectivebiological
control ofthe filbertaphid. Theelimination oftheearly-seasontreatments forthe filbertaphid
may enable the establishment of populations of beneficial insects that prey on filbert
leafrollers. Fewleafrollershavebeenobserved in abandoned hazelnutorchards, in contrastto
managed orchards where leafroller populations are continually building.
Theestimatedcostofinsecticidetreatmentforthecontroloffilbertleafrollerwas$213,688
in 1980($406,007 1997 dollars) . In 1997 the estimated costwas$274,190(Table4). This is
adecrease in costof$131,817 (Table 7), correspondingto a reduction ofmorethan 7,445 kg
ofinsecticide (a.i.), and a decrease ofnearly 25% in the area treated with insecticide.
Obliquebanded Leafroller, Choristoneurarosaceana(Harris), (Lepidoptera: Tortricidae)
Obliquebanded leafroller(OBLR)populationsoccasionallyincreaseto levelsofeconomic
injury. However, firstgenerationOBLRpopulations aremanaged when sprays areappliedto
control filbert leafroller since they are present concurrently. In 1980, 1,862 kgofinsecticide
i
12 J.ENTOMOL.SOC.BRIT.COLUMBIA97,DECEMBER2000
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(a.i.)wereappliedby6%ofthegrowersto 5%ofthehazelnutareatocontrolOBLR(Tables2
and 5). In 1997, 153 kg ofinsecticide (a.i.) were applied by 2.5% ofthe growers to 2.5% of
the hazelnut area. The insecticides used were Asana® and Guthion®.
Thepeststatusoftheobliquebanded leafrollerhasdeclined inhazelnutorchardsduringthe
16-yearperiodbetween 1980and 1997. Howeversomegrowers(2.5%)stillapplyinsecticides
to control this pest. Cost adjustments between 1980 and 1997 show that an annual saving of
over$26,000 wasachieved byadopting IPM practices in hazelnutorchards (Tables 5 and 7).
As observed with control of filbert leafroller, a decrease ofgreater than 50% in the total
hectarestreated occurred as aresult ofthe establishmentofan IPM program to manage pests
in hazelnut orchards.
Filbert Aphid, Myzocallis coryli (Goeze) (Homoptera: Aphidae)
The mostdramatic change in insecticide use patterns inhazelnutorchards has occurred in
thecontrol ofthe filbertaphid. In 1980, 6,809 kga.i. ofinsecticidewereappliedby49%ofthe
growers on 69%ofthe hazelnutareato control this pest (Tables 2 and 6). In 1997, 440 kg of
insecticide (a.i.) were applied by 5% ofthe growers to 6% ofthe hazelnut area. A 15-fold
reduction in the volume ofinsecticides, and a 10-fold reduction in the area treated occurred
during the 16-year interval between surveys.
Thefilbertaphidwasaseriouspestofhazelnuts; reproducingparthenogenetically, ithas6-
8 generations each year (AliNiazee and Messing 1995). It was an ideal candidate for the
development of resistance that occurred every 1-3 years (Katundu and AliNiazee 1990).
Therefore, findingandestablishingan effectivebiological control washighlydesirable. From
the results of natural enemy surveys, it was concluded that filbert aphid was a suitable
candidate for a classical biological control program based on the introduction of a host-
specific parasitoid. Duringthe 1984-1985 seasons, Trioxyspallidiis Haliday (Hymenoptera:
Aphidiidae), an effective parasitoid from Europe was introduced by Messing and AliNiazee
(1989)tocontroltheaphid. Theparasitoidreadilyestablished; studiesconducted in 1987 and
1988 showed that T. pallidus had an average level ofparasitism of25 -50% (AliNiazee and
Messing 1995). This biological control program is noted as one of the most successful
introductions ofa biological control agent on record (AliNiazee and Messing 1995), and it
resulted in an importantreduction intheuseofinsecticidesonhazelnuts. Anestimated 5%of
the hazelnut growers are currently using insecticides on 6% ofthe filbert acreage to control
filbert aphid - a reduction in the use of insecticides by 90% ofthe growers on 91% ofthe
hazelnutarea. Thistranslatesto avastenvironmental benefit interms ofthetotal reductionof
pesticides used in Oregon hazelnut orchards.
Not only has the establishment ofthe T. pallidus wasp had a favorable impact on the
environment, but ithas resulted in large economic savings as well. The reduction in pesticide
use on hazelnuts has directly increased the profitability ofgrowinghazelnuts in Oregon. The
total area treated for filbert aphid was reduced from 69% to 6%, a reduction of91%. This
reduction ofinsecticide use on filbert aphid has resulted in an annual savings ofnearly one-
half-million dollars (Tables 6 and 7).
In summary, the insecticide use pattern on hazelnuts in Oregon has changed dramatically
duetothe establishmentofasuccessful IPM program. A keycomponent ofthis program was
the successful release ofa parasitic wasp as a biological control agent. Additionally, more
effective samplingandmonitoringmethods forfilbert leaft-ollerandobliquebanded leafroller
and the establishment ofeconomic levels of injury have reduced the use of insecticides to
control infestations. Theadoptionofaneffective IPM systemandeffectivebiological control
agent ofa single pest have beneficially influenced the entire pest management strategy for
hazelnuts; reducing grower costs by large amounts each year, and significantly reducing
.
16 J.ENTOMOL.SOC.BRIT.COLUMBIA97,DECEMBER2000
environmental pollution associated with the production ofan agricultural commodity in an
environmentally sensitive area.
Table 7
Costs to control hazelnutpests usingthe CPI ratio of469/247 (1.9) to express 1980 costs
as 1997 values.
Insect pest Estimated cost to Value in 1997 $ Estimated cost to Estimated change
'
control in 1980 control in 1997
Filbertworm 560,783 1,065,488 1,275,832 +210,344
Filbert leafi-oller 212,490 403,731 274,190 -129,541
OBLR 31,304 59,478 33,335 -26,143
Filbert aphid 323,374 614,411 48,666 -565,745
Total $1,127,951 $2,143,108 $1,632,023 -$511,085
ACKNOWLEDGEMENTS
Drs. Russell MessingandGlen Fisherhavebeen instrumental inestablishingthehazelnut
IPM program and conducting the 1981 survey. We are thankful for their assistance in this
project.
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