Research Priorities in California

Western Region IPM Ant Workshop

Urban Pest Ants of California*

Argentine ant 25.9% Southern fire ant 19.3% Odorous house ant 11.1% Carpenter ants 9.5% Other species 34.2%

*Knight, R.L., and M.K. Rust. 1990. The urban ants of California with distribution notes of imported species. Southwestern Entomologist 15: 167-178.

Urban Pest Ants of San Diego*

Argentine ants 84.5% Harvester ants 5.2% Crazy ants 1.8% Little black ants 1.6% Southern fire ants 1.3% Velvety tree ants 1.0% Other species 4.6%

*Field, H.C., W.E. Evans, R. Hartley, L.D. Hansen, and J.H. Klotz. 2007. A survey of structural ant pests in the southwestern USA. Sociobiology 49: 151-164.

Lloyd Pest Control of San Diego

≈ 35,000 general pest accounts– Major portion of this business is Argentine ant control

Mountain Communities

San Bernardino Mts.– No Argentine ants– Other ant pests

Velvety Tree Ants

Liometopum luctuosum

Red Imported Fire Ants

Argentine Ants

Major priority in CA– Structural Pest Control– Homeowners

Major research focus– UCR urban program*

*Vega, S.J., and M.K. Rust. 2001. The Argentine ant – a significant invasive*Vega, S.J., and M.K. Rust. 2001. The Argentine ant – a significant invasivespecies in agricultural, urban and natural environments. Sociobiology 37: 3-25.species in agricultural, urban and natural environments. Sociobiology 37: 3-25.

Turning Point for PMP’s

Approval in CA– December 10, 2002

Impact on Structural Pest Control

Lloyd Pest Control– Callbacks

2002: 60,000 2003: 55,000 2004: 39,000

– 16,000 fewer– Estimated savings =

$500,000.00

Fipronil*

Slow-acting Non-repellent Horizontal transfer

*Soeprono, A.M., and M.K. Rust. 2004. Effect of horizontal transfer of barrier insecticidesto control Argentine ants. J. Econ. Entomol. 97: 1675-1681.

*Soeprono, A.M., and M.K. Rust. 2004. Effect of delayed toxicity of chemical barriersto control Argentine ants. J. Econ. Entomol. 97: 2021-2028.

Revolutionized Ant Control

Most effective treatment to date in CA

– Use pattern (AI) 2003: 13,516 lbs. 2005: 66,678 lbs.

Appearance in water runoff from urban areas

Research Priority

Preservation of insecticides– Developing control strategies that mitigate runoff

without sacrificing efficacy

Evaluating Control Strategies for Argentine Ants Around Homes

Methods developed by Mike Rust, whose Laboratory team coordinates the summer ant control program at UCR

Estimating Population Levels of Ants

Sugar water consumption over 24 hours– 10 vials near house– 10 vials in yard

Reierson et al. 1998* 0.3 mg per visit to

calculate average number of ant visits/vial near and away from the house over 24 hours

*Monitoring with sugar water to determine the efficacy of treatments to control Argentine ants, Linepithema humile (Mayr): 78-82. Proc. Natl. Conf. Urban Entomol. 1998, San Diego, CA.

Monitoring

Before and after treatments applied Treatments replicated at 5 homes

Standard Treatment with Termidor

Backpack sprayer– 3-4 gallons spray

0.06% fipronil

– Around perimeter 1 ft. x 1 ft.

– Along edges Driveway Sidewalks Other areas

Termidor Spray

Weeks After Treatment

0

10000

20000

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of A

nt V

isi ts

NearAway

LOCATION

Termidor Perimeter Spray

Time

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20072006

93% 97%81%

65%

77%

35%

Spot Treatment

One gallon of Termidor – Only active ant trails

Capitalize on horizontal transfer of fipronil

Termidor Spot Treatment

Weeks After Treatment

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LOCATION

Termidor Spot Spray

Time

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LOCATION

2006 2007

90%

40%

46%

28%

Talstar Spray (0.06% Bifenthrin)Talstar Perimeter Spray

Time

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10000

20000

30000

40000

50000A

v era

ge n

o. of A

nt Vis

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NearAway

LOCATION81%71%

24%

3-4 gal. spray around perimeter of house + edges of sidewalks, driveway,and other areas ants tend to trail

2007

Research Priority

Liquid bait development Field trials

– 2006: Gourmet (1% borate)

– 2007: Vitis (0.001% imidacloprid)

Liquid Baits

Weeks After Treatment

0

10000

20000

30000

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Mean #

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LOCATION

Vitis Bait

Time

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LOCATION

Gourmet Vitis

73% 83%

Vitis

Further evaluations by Lloyd Pest Control– Cost analysis: baits vs. sprays– Potential use by PMP’s

Survey of Homeowners

95% rated the treatments as “very effective”

Excellent products and strategies

– To ensure future use Use judiciously

2008Refinements of Spray Applications

More target-specific Less likely to runoff

– Testing Pin-stream vs. fan

spray No spray zones

– Within 15 ft. of street– Within 5 ft. of

driveway or sidewalks Evaluated for efficacy

and runoff

Film production by Cheryl Wilen and Ray Lucas

2009Long-Term Control Programs

With Termidor and Talstar– Two spot applications

May and August

– Monitor efficacy and runoff

Combination Spot-Spray + Baits

Virtual Baiting by Choe and Rust

Bait as an attractant– To lure ants over a

fipronil-treated surface

Environmentally-friendly, targeted ant control

Goals

Preserve the use of fipronil and other compounds in ant control

Provide new control strategies with little environmental impact

Evaluate Homeowner Products?

Determine how to use most effectively

– Home Defense– Liquid borate baits– Cedar mulch– Caulking

Homeowners contribute to runoff

– Require guidelines for safe and effective use of these products

New Research Initiative

Biology and control of velvety tree ants– Liometopum occidentale– Liometopum luctuosum

Misidentified as carpenter ants– Excavate wood and insulation– Polymorphic– Mesosoma with smooth even profile– Significance as structural pests unknown

Survey

Document status as WDO’s Pest control companies in foothill and

mountain communities– Cooperator in San Bernardino Mts.– Laurel Hansen in PNW– Need other cooperators

Survey

Samples of ants Location of infestations Damage Treatment strategies

– Velveties– Carpenter ants– Odorous house ants– Other species causing problems

Comparative Study

Colony dynamics– Colony size? Reported to be large

Mark-recapture studies Colony extraction

– Aggression tests Define territory Number of satellite nests

– Colony multiplication and queen numbers? Budding, mating swarms, or both? If mating flights, when? Mono- or polygyne?

Comparative Study

Ecology– Habitat differences

L. occidentale: sea level – 4,800 ft.– Deciduous trees

L. luctuosum: higher elevation up to 8,000 ft.– Conifers

– Areas of overlap Competitive displacement?

Comparative Study

– Foraging behavior Foraging rhythms? Diet

– Tend hemipterans– Predators– Scavengers

Control

Bait development– Granular– Liquids

Use choice tests

– For control– For monitoring efficacy

of treatments Current control

methods– Barrier sprays

Conclusion

Research priorities– Overall pest status in CA

Argentine ants

– Urban population in mts. Different set of ants