Reduced Area-Agent Reduced Area-Agent Treatments (RAATs): Do Treatments (RAATs): Do

More With LessMore With Less

Scott Schell and Alex LatchininskyScott Schell and Alex Latchininsky

Extension EntomologyExtension Entomology

Dept. of Renewable Resources - CESDept. of Renewable Resources - CES

Grasshopper Grasshopper Treatment Application Treatment Application

Strategies:Strategies:Conventional/Blanket/Conventional/Blanket/

100%100%

RAATsRAATs

THE RAATs CONCEPT:THE RAATs CONCEPT:- Hoppers killed directly in the treated swaths- Hoppers killed directly in the treated swaths

- More predacious insects and parasitoids - More predacious insects and parasitoids survive treatment survive treatment

- Hoppers move into treated strips - Hoppers move into treated strips

- Birds continue to feed on hoppers- Birds continue to feed on hoppers

- Less disruption to bio-control agents of - Less disruption to bio-control agents of weeds (APHIS data on weeds (APHIS data on AphthonaAphthona spp. beetles spp. beetles on leafy spurge in Montana)on leafy spurge in Montana)

Mid-MayMid-MayThru June Thru June

Optimal for treatmentsOptimal for treatments

Abbreviated History of RAATs StrategyAbbreviated History of RAATs Strategy

1995 – 2002: UW and Cooperators: 240 40 acre+ plots and 16 large plots1995 – 2002: UW and Cooperators: 240 40 acre+ plots and 16 large plots

1998 – 1999: APHIS conducts successful RAAT tests in South Dakota1998 – 1999: APHIS conducts successful RAAT tests in South Dakota

1997 – 2001: Used in Russia and central Asian countries1997 – 2001: Used in Russia and central Asian countries

2001 - Tested versus blanket coverage in CA on extreme grasshopper 2001 - Tested versus blanket coverage in CA on extreme grasshopper densitiesdensities

1999 – 2001: Used in Utah and Nevada on grasshoppers and Mormon 1999 – 2001: Used in Utah and Nevada on grasshoppers and Mormon cricketscrickets

2000 – 2001: Used on large outbreaks in Oregon2000 – 2001: Used on large outbreaks in Oregon

1999 – 2004: Over 500,000 of acres protected in Wyoming commercially1999 – 2004: Over 500,000 of acres protected in Wyoming commercially

Aerial chemical Aerial chemical crop protection [1945]crop protection [1945]

Treated swath: 75-90 ftUntreated swath: 135-150

ft

UW RAATs brochureUW RAATs brochure

Treated swath: 100 ftUntreated swath: 100-

200 ft

Proven RAATs StrategiesProven RAATs Strategies

4 oz of Malathion*- RAAT- 80% 4 oz of Malathion*- RAAT- 80% CoverageCoverage*Fyfanon® ULV*Fyfanon® ULV

100 ft

Tre

ated

(80

%)

Un

trea

ted

(20

%)

20ft

Un

trea

ted

(50

%)

8 oz of Carbaryl*- RAAT- 50% 8 oz of Carbaryl*- RAAT- 50% CoverageCoverage

with 8oz of water at pH with 8oz of water at pH 7 7*Sevin XLR Plus® or Generic Equivalent*Sevin XLR Plus® or Generic Equivalent

Tre

ated

(50

%)

100 ft

100 ft

Un

trea

ted

(50

%)

0.75 oz of Dimilin 2L0.75 oz of Dimilin 2L®® - RAAT- - RAAT- 50% Coverage50% Coverage

with at least 8 oz of water and 4 oz Crop with at least 8 oz of water and 4 oz Crop Oil Conc.Oil Conc.

Tre

ated

(50

%)

100 ft

100 ft

1 oz of Dimilin 2L- RAAT- 33% 1 oz of Dimilin 2L- RAAT- 33% CoverageCoverage

with 15 oz of water and 8 oz oil (7 with 15 oz of water and 8 oz oil (7 Canola:1 COC) Canola:1 COC)

Un

trea

ted

(66

%)

Tre

ated

(33

%)

100 ft

Don’tExceed 200 ft

Standard Standard vs. vs. RAATsRAATs :: ControlControl Control is 5 to 15% lower than conventional blanket

methods..AgentAgent oz./coverage% oz./coverage% Method Method % Control% Control

CarbarylCarbaryl 16/10016/100 Standard Standard 85-9585-95

8/50 8/50 RAAT RAAT 75-8575-85

MalathionMalathion 8/100 8/100 StandardStandard 90-9990-99

4/804/80 RAAT RAAT 75-8575-85

DimilinDimilin 1/100 1/100 StandardStandard 95-9995-99

0.75/50 0.75/50 RAATRAAT 80-9080-90

Some Comments on EfficacySome Comments on Efficacy

•It costs a lot to kill them all.It costs a lot to kill them all.

• Surviving grasshoppers provide a prey base Surviving grasshoppers provide a prey base

for the predators.for the predators.

• We haven’t observed any resurgence the We haven’t observed any resurgence the

following year in treated areas.following year in treated areas.

THE RAATs CONCEPT:THE RAATs CONCEPT:Economic MotivationEconomic Motivation

1) Assume 50% of cost is insecticide and 1) Assume 50% of cost is insecticide and 50% is 50% is application.application.

2) Assume Total cost of a program is 2) Assume Total cost of a program is $4.60/ac.$4.60/ac.

3) Assume 25% reduction of application rate applied to 3) Assume 25% reduction of application rate applied to alternate swaths.alternate swaths.

4) Results:4) Results:Application =$2.30/2 =$1.15 Application =$2.30/2 =$1.15 Insecticide =$2.30 x .75 (agent) Insecticide =$2.30 x .75 (agent)

=$1.73/2 (area) =$1.73/2 (area) =$0.87=$0.87Total cost perTotal cost per protectedprotected acre =$2.02acre =$2.02

THE RAATs CONCEPT:THE RAATs CONCEPT:Policy MotivationPolicy Motivation

1) The new USDA-APHIS EIS 1) The new USDA-APHIS EIS endorsesendorses the the use of RAATs for range land treatment use of RAATs for range land treatment programs.programs.

3) Cost of conventional treatments can 3) Cost of conventional treatments can exceed the exceed the monetary valuemonetary value of the of the forage protected.forage protected.

2) Lots of 2) Lots of moneymoney, Government or Private, , Government or Private, will be saved if grasshopper control is will be saved if grasshopper control is needed by using RAATsneeded by using RAATs

THE RAATs CONCEPT:THE RAATs CONCEPT:Environmental MotivationEnvironmental Motivation

1) Exploiting grasshopper movement 1) Exploiting grasshopper movement allows allows acceptable managementacceptable management and and untreated untreated swaths.swaths.

3) Less insecticide means 3) Less insecticide means less riskless risk to human and to human and environmental health.environmental health.

2) The untreated swaths allow the survival and 2) The untreated swaths allow the survival and re-colonization of beneficial and non-target speciesre-colonization of beneficial and non-target species..

ExceptionsExceptions

Higher rates or coverages may be needed if:Higher rates or coverages may be needed if: - - treatments are applied to late instar nymphs treatments are applied to late instar nymphs

(especially if using Dimilin 2L), (especially if using Dimilin 2L), - ground temperatures exceed air temperatures - ground temperatures exceed air temperatures

(especially if using malathion), (especially if using malathion), - grasshopper densities are extreme, - grasshopper densities are extreme, - forage cover is tall or dense, or - forage cover is tall or dense, or - terrain is rough. - terrain is rough.

In all cases, grasshopper management software In all cases, grasshopper management software (CARMA or HOPPER) should be used to assess a (CARMA or HOPPER) should be used to assess a program. Apply insecticides in accordance with label program. Apply insecticides in accordance with label directions and established guidelines for buffers directions and established guidelines for buffers around water, bees, and human habitations.around water, bees, and human habitations.

CARMA can be downloaded from CARMA can be downloaded from Grasshoppers of Wyoming and Grasshoppers of Wyoming and

the Westthe West at: at: www.wygisc.uwyo.edu/grasshopper/www.wygisc.uwyo.edu/grasshopper/or request a free or request a free Grasshoppers: Their Biology, Identification and Grasshoppers: Their Biology, Identification and

ManagementManagement CD-ROM from:CD-ROM from:

www.sidney.ars.usda.gov/grasshopper/www.sidney.ars.usda.gov/grasshopper/You can also write or call in your request to the:You can also write or call in your request to the:

USDA-ARS Northern Plains Agricultural Research Laboratory, USDA-ARS Northern Plains Agricultural Research Laboratory, 1500 N. Central Ave.1500 N. Central Ave.

Sidney, Montana 59270. 406/433/2020.Sidney, Montana 59270. 406/433/2020.