Texas Imported Fire Ant Research and Management Plan

Texas Imported Fire Ant Research and Management Plan Fire Ant Management in Recently Infested Areas Presentation created by: Dr. Charles L. Barr, Extension Program Specialist - Fire Ant Project

The Red Imported Fire Ant (Solenopsis invicta) The advance of the red imported fire ant into the southwestern U. S. presents new challenges for their control. Some of the practices used in the past have actually worsened fire ant problems in the SE part of the country. The practices listed here will help minimize both current and future fire ant problems. First, the good news. . .

Fire Ant Facts in Arid Climates The Good News • Fire ants are not well adapted to arid environments - they are dependent on finding water daily - they prefer high humidity - they cannot tolerate low temperatures for long periods - they cannot tolerate high temperatures for long periods without adequate moisture • Therefore, fire ants will most likely be found only in urban areas and/or around water sources • You probably don’t have them!

Fire Ant Facts in Arid Climates The Bad News Fire ants don’t always follow the rules. They’re heeeeeere. . .

• A quarantine does not imply county-wide infestation • Lack of quarantine does not imply absence of fire ants in the county

Red Imported Fire Ant Facts Solenopsis invicta • Imported from South America through Mobile, Alabama. Established by 1930’s, now as far north as Delaware, as far west as California and as far south as Rio Grande. • An average “Texas” colony has 50 -100, 000 workers • A queen can live 2 -5 years, workers 6 -18 months • An ant goes from egg to adult in about 3 weeks • All worker ants are sterile females, despite what you see in the movies (they also have 6 legs)

Primary Means of Distribution Natural Mating flights: - may scatter mated queens over dozens of miles - high queen mortality due to birds and insects in the air and other ants on the ground - usually occurs the first sunny day after a rain - different mounds launch flights at different times - takes 3 - 6 months for mound to become visible Colony movement/budding: - movement from a few to dozens (hundreds? ) of feet - complete re-location in a matter of hours - entire colonies can float miles in floodwater

Primary Means of Distribution Artificial/Human-Assisted - Turf and sod - Nursery products - Bee hives Quarantined and regularly inspected by TDA - Hay - Firewood - Soil, gravel, etc. Quarantined, but inspection/ enforcement within state is nearly impossible - Equipment - Almost anything else left outdoors, then transported

Life Stages in a Mature Fire Ant Colony Fertile Queen Larvae Pupae Workers (all sterile females) minor major Egg Clutch (10+Clutch eggs) Worker Life Stages Reproductive Life Stages Larvae Female (future queen) Pupae Male

Single vs Multiple Queen Ant Colonies Single Queen Multiple Queen • One reproductive queen • Many reproductive queens • Larger worker ants • Smaller worker ants • Territorial behavior • Share workers and resources • Larger mounds • Smaller mounds • Lower mound density: less than 150 per acre, usually 10 -50 • Higher mound density: greater than 150 per acre, commonly 200 -300 • More ants per unit area, a moderate infestation can have 1 ant/square inch • Fewer ants per unit area • Predominate form in South • Predominate form in Texas

IDENTIFICATION Quick Field Guide Size: workers are 1/8” - 1/4” long, but come in a wide range of sizes in the same mound • Harvester and some other ants are much larger • Many other species are smaller or have worker ants of only one size

Fire ant workers Fire ant Queen

IDENTIFICATION Quick Field Guide Color: fire ants are a dark reddish-brown color with a shiny, opaque black abdomen Other ants are commonly: • black to pale brown • a single color • somewhat transparent

Red imported fire ant workers Little black ants (attacking fire ant queen) Pharoah ant Carpenter ant

IDENTIFICATION Quick Field Guide Behavior: fire ants swarm out of the mound when disturbed and rapidly climb on anything nearby Most other ants will either not swarm out, will run away from the disturbance or will ignore it

IDENTIFICATION Quick Field Guide Mounds: piles of fine granular soil with no or many entry holes. Highly variable in size. No denuded area around mound. Other species may have: • no mound structure at all • mounds with a single entry hole • mounds with a distinct, sculpted shape • denuded area around mounds

Diffuse fire ant mound in sandy, dry soil

Large fire ant mound in heavy clay

~ 6 inches Typical fire ant mound in lawn

Harvester ant nest Pyramid ant mound ~ 2 inches ~ 3 feet

What to do if you think you have an infestation of red imported fire ants - Mark the suspect mound for easy re-location - Call the Extension Agent in your county - Take worker ant samples and mail as instructed (collect at least 25 ants from mound center and seal in small vial or container in alcohol) Finding red imported fire ants will not necessarily result in quarantine. It may allow early treatment and elimination, thus avoiding quarantine or their spread into a more serious infestation.

Fire Ant Management “Eradication” of fire ants is not technically, economically or socially practical. However, it is possible to eliminate or minimize the problems that they cause. It may be possible to eliminate or prevent infestations in unfavorable environments for long periods with effective quarantines, early detection and effective, environmentally responsible treatments.

Integrated Pest Management (IPM) Integrated Pest Management does NOT mean eradicating the pest It means reducing or eliminating pest-caused problems at an acceptable cost

Integrated Pest Management (IPM) Utilizing the: • most effective • least expensive • least toxic • site specific method or product to reduce pest problems to below an economically or socially acceptable level.

Community-wide Fire Ant Management Fire ants can be better managed when neighbors work together. It may be possible to eliminate isolated fire ant infestations, but only as long as all property owners cooperate in the effort.

Fire Ant Management in Ornamental Turf Program Approach • Includes sites such as: home yards business lawns golf courses cemeteries parks and playgrounds • Does not include sites such as: gardens orchards pasture and rangeland hay meadows any type of crop growing area

Fire Ant Management in Ornamental Turf Program #1 The “Two Step” Method Use in areas with high mound density and where thorough, rapid, long lasting control is needed using a minimum amount of chemical. Ideal for home lawns. 1. Treat with a broadcast bait to get the “unseen” mounds. 2. Wait 3 -4 days for the ants to pick up the bait. 3. Use an individual mound treatment to treat ONLY the mounds that are an immediate nuisance. Don’t kill every mound twice.

Fire Ant Management in Ornamental Turf Program #2 Individual Mound Treatments Only Best for areas of low mound density where re-infestation is slow and for areas with competing (native) ants that might be harmed by baits. Expensive on a per acre basis, but requires only one product. 1. Locate and treat every fire ant mound possible at the same time. 2. Re-treat as new mounds appear.

Fire Ant Management in Ornamental Turf Program #3 The “Ant Elimination” Method Best for areas where there must be absolutely no ants including situations such as yards with children, special events, high traffic areas, picnic areas, etc. Immediately suppresses ants, but will not eliminate colonies unless done repeatedly. 1. (Optional) Apply a broadcast bait for longer control. 2. Broadcast (spray or granules) a contact insecticide over the entire area. Suppression will last 8 -12 weeks, at most. 3. Repeat as needed.

Fire Ant Management in Ornamental Turf Program #4 The Broadcast Bait Only Method Best for areas with high mound density, but where cost is a consideration, maximum control is not needed and speed of suppression is not a critical factor. 1. Apply a broadcast bait, preferably a fast-acting type. 2. When “tolerance level” is reached, apply a slow-acting broadcast bait for longer control. 3. Maintain monitoring and treatments, usually once or twice per year.

Individual Mound Treatments There are over 100 products labeled for control of individual fire ant mounds, but they fall into a few broad categories. Always read label directions. Granules: applied dry, but usually require watering in [Ex. Diazinon, Dursban (chlorpyrifos), pyrethroids, etc. ] Drenches: pre-mixed and poured on mound [Ex. Chlorpyrifos, pyrethroids, most “organics”, etc. ] Dusts: applied dry [Ex: Sevin (carbaryl), Orthene (acephate), etc. ] Devices: numerous types; often kill many ants, but tend not to eliminate colonies

Choosing a Product or Method Baits vs Individual Mound Treatments (IMT) Use an individual mound treatment when: - there are few fire ant mounds, <20 per acre - there are populations of other ant species - rapid, near 100% control is desired - weather is too cool for ants to be foraging for bait Use a broadcast bait when: - there are many fire ant mounds - there are few other ant species - cost or labor too great to treat individual mounds - pesticide runoff/toxicity is a concern - large areas need to be treated - speed and 100% control is not needed

BAIT COMPARISON Active Ingredients Manufacturer Active Ingredient Brand Name(s) Am. Cyanamid hydramethylnon Amdro, Siege Novartis fenoxycarb Logic, Award Novartis abamectin Ascend, Clinch Wellmark (Zoecon) s-methoprene Extinguish Spectracide Valent pyridine* pyriproxyfen* Nylar Distance Dow Agro. Sciences spinosad Eliminator w/Conserve Griffin sulfluramid ?

Some currently available bait products.

BAIT COMPARISON Speed of Action Active Ingredient -----Mound suppression-----Initial Maximum Relative hydramethylnon 1 -2 weeks 2 -6 weeks fast fenoxycarb 3 -6 weeks 2 -6 months very slow abamectin 2 -4 weeks 2 -4 months intermediate s-methoprene 3 -6 weeks 2 -6 months slowest pyriproxyfen 2 -4 weeks 2 -4 months intermediate spinosad 1 -2 weeks 2 -6 weeks fast sulfluramid 1 -2 weeks 2 -6 weeks fast Speed of activity is dependent on environmental factors

BAIT COMPARISON Duration of Control Active Ingredient hydramethylnon Time to return to pre-treatment infestation* relative 6 -12 months short fenoxycarb 12 -18 months very long abamectin 12+ months* intermediate s-methoprene 12 -18 months* very long pyriproxyfen 12+ months* intermediate spinosad 6 -12 months* short sulfluramid 6 -12 months* short Re-Infestation times are highly dependent on many environmental factors * re-infestation times not fully determined

BAIT COMPARISON Use Sites Non-ag land turf, etc Agric. Sites Active Ingredient Brand hydramethylnon Amdro Siege yes PCO use pasture, hay none fenoxycarb Logic Award yes PCO use limited none s-methoprene Extinguish yes almost all abamectin Ascend Clinch Distance PCO use yes (ag. ) yes none limited none pyriproxyfen

Tips for Successful Bait Application • Use fresh product! - less than 2 years old if container is sealed - less than 1 year old if container has been opened - Store in cool area in tightly sealed container - If it smells rancid, it is! Results will be poor. • Apply only when ants are foraging 75 - 90 F, summer=late afternoon; winter=mid-afternoon • No rain expected within 24 hours, dew has dried • Use proper application equipment

Selection of an Application Device: Small Areas (yards, less than 1 acre ) Hand-held seeder • Cost: less than $10 • Power: hand • Bait capacity: 1 - 3 lbs. • Swath width: 8 - 10 ft. • Availability: retail, feed, hardware • Comments: for occasional use on small areas only, tends to over-apply product and feed poorly, but very inexpensive

Selection of an Application Device: Medium Areas (1 - 5+ acres ) “Belly Bumper” Seeder • Cost: $40 -50 • Power: hand • Bait capacity: 10 -15 lbs • Swath width: 10 -15 ft. • Availability: feed stores • Comments: can be calibrated very accurately, durable, operator can sit on vehicle to cover much more area. Canvas bag model is much more available

Selection of an Application Device: Large Areas (over approx. 5 acres ) Herd Model GT-77 Seeder • Cost: $250 -$320 • Power: 12 V • Bait capacity: 20+ lbs. • Swath width: 25 -35 ft. • Availability: any farm equipment dealer • Options: fixed or adjustable gate (recommended) numerous mounting options (ATV’s, tractor, etc. )

Individual Mound Treatments vs Broadcast Baits: Speed and Duration of Control Individual mound treatment comb. Orthene Untreated Amdro (ind. md) (broadcast) Logic (broadcast) 3 5 October, 1997 13 23 34 60

Broadcast Baits vs Individual Mound Treatments (IMT’s) - When used properly, IMT’s gave (and will give) near-100% control consistently - IMT’s worked quickly, but mounds rebounded within 3 months, probably due to missed mounds - Broadcast Amdro worked almost as quickly as IMT’s, but gave over 7 months of control - Logic (or any IGR bait) when applied in the fall, may take over 6 months to reach full suppression

Individual Mound Treatments vs Broadcast Baits: Per Acre Cost of Treatment $118. 39 $79. 89 $58. 89 $53. 39 $60. 89 $15. 20* $17. 70* Calculations based on 150 mounds per acre. Individual mound treatment costs will vary with density, but will not fall to zero due to mound location costs. * Cost does not change regardless of mound density.

Broadcast Baits vs Individual Mound Treatments (IMT’s) - Just locating mounds to be treated with an IMT can cost more than treating with a broadcast bait. - The labor for IMT’s includes walking, mixing and handling potentially toxic pesticides, and often carrying gallons of water. Broadcast baits require only walking or riding. - The cost of treating with IMT’s varies with the number of mounds, but never goes to zero. - The cost of broadcast baits is fixed on an area basis, regardless of the number of mounds present.

Choosing a Product or Method Baits vs Individual Mound Treatments (IMT) Baits Slow to work IMT Fast to work (weeks to months) (hours to days) Long time to re-infest Can re-infest area almost immediately (months to over a year) Low labor Fixed cost per acre ($15+ per acre regardless of mound density) High labor Fixed cost per mound ($0. 25 or more per mound regardless of density)

Fire Ant Management in Recently Infested Areas - Conclusions • Red imported fire ants are not well adapted to arid environments. They exist, but are not common. Assume, first, that ants you find are not fire ants. • Proper identification and non-treatment of native/desirable ants will help preserve them, thereby lessening the possibility of fire ant invasion • Early detection and reporting can prevent or contain an infestation, preventing quarantine

Fire Ant Management in Recently Infested Areas - Conclusions • In most recently infested areas, individual mound treatments will be the best control option • However, elimination of fire ants from an area is probably best achieved through the use of both broadcast baits and individual mound treatments Most importantly, don’t panic! Over-reaction can make the problem worse. You can live with fire ants.

Questions? http: \fireant. tamu. edu