Florida's TermitesBiology and Control

Prepared by

Jerry E. Gahlhoff Jr.Department of Entomology and Nematology

University of Florida, Gainesville 32611

Termite Damage

Termites cost Floridian's over $500 million per year

Termite vs. AntA Source of Common Confusion

Termite Ant(Isoptera) (Hymenoptera)

1. Constricted waist2. Elbowed antennae3. Dissimilar wing size

1. Broad waist2. Beaded antennae3. Similar wing size

Termite Life Cycle

Three General Categories Of Termites

Subterranean - Over 75% of the problem

Drywood - About 20% of the problem

Dampwood - not of much structural concern in Florida

Subterranean Termites

Most common and damaging termites in Florida

Also includes formosan termite which occurs in several locations in Florida

Workers are most numerous of the three castesColonies may contain from 50,000 to 5 million workersForaging distance of 230 feetWorkers forage for food; tend eggs, young, and reproductives; build tubes

EasternSubterranean

Termite Workers

EasternSubterranean

Termite Worker

Workers have chewing mouthparts and cause all the damage in wooden structuresWorkers are cream colored, soft bodied, and blindThis caste cannot be used for identification

Eastern Subterranean Termite Wood

Damage

Workers feed in the soft portion of the woodCreate galleries lined with a muddy fecal materialLarge colonies consume 1 pound of wood per dayTermites feed on anything composed of cellulose

Eastern Subterranean Termite Feces

Fecal material is usually incorporated into carton tubesFecal material is more moist than that of drywood termites and contain lignin, the relatively indigestible portion of wood

Subterranean Termite Mud

Tubes

Tubes are made of mud and cartonCarton is made of partially chewed wood, feces, and soil packed togetherTubes serve to maintain humidity required for survival and to protect from predators

EasternSubterranean Termite Entry Into Buildings

This occurs around pipes or other utilities that penetrate the concrete slab of a structureWorkers use carton tubes to gain entry and create a "highway" in which they travel to and from the nest to forage

Eastern Subterranean

Termite Soldier

Rectangular shaped, reddish-brown head and cream colored bodySoldiers comprise only 1 to 3% of the foraging termite populationSoldiers preserved in 70% isopropyl alcohol are useful in identification

Head Of Subterranean

Termite Soldier

Smooth mandibles protrude from the front of the soldier's headHead is specialized for defending the colonyUnable to feed due to position of the mandibles, fed by workers

Termite Queen

Subterranean Termite Alates

Winged reproductive termitesSwarm during the dayAfter swarming they drop their wings and look for a nesting siteThis stage is often confused with ants

Subterranean Termite

WinglessReproductive

After swarming, alates break off their wings and search for a site to begin a new colonyBurrow into ground or rotten wood where the queen lays eggs to start new colonyAfter a swarm, de-alated reproductives are often found on the floor or near windows

Formosan Subterranean Termite

Most aggressive and destructive termite in the U.S.

Prevalent in Dade and Broward counties but also found in Orlando, Tampa, and in Florida panhandle

Native Termites Formosan Termite

Soldiers

Identification

Homeowner Prevention

Avoid wood to ground contact

Avoid exterior finishes (i.e. stucco) below grade

Proper installation of gutters and downspouts

Avoid sprinkler system directed toward walls

Avoid disturbing soil directly around structure

Treatment For Subterranean Termites

Traditional chemical barrier around and under home

Termite baiting systems

Treatment of wood with borates

Other

Chemical TreatmentsRepellents: mostly used as pretreatments (before pad is poured)• Talstar - bifenthrin• Demon – cypermethrin• Various others – permethrinNon-repellent: posttreatments (after construction)• Phantom – chlorfenapyr• Termidor – fipronil• Premise – imidicloprid

Typical Subterranean Termite Post Construction Treatment Process – Drilling, Ditching and Foaming.

Where trenching can’t be done in soil such asconcrete pads up against the foundation, like in patios, entry ways and garages, holes need to be drilled to the soil and treated.

Injection of chemical below pad with 4 hole nozzle tip

Filling of holes with rubber bullet and then cement calking.

Bullet plugs are tapped 1 inch into hole with drill bit

Hole is filled in with caulking compound

Ditch all areas outside of foundation walland treat with termiticide.

Injection of chemical into and below ditch

Ditched area is filled with recommened amount of chemical

Use a foam machine to inject termiticide intobathroom water lines and any suspicious outsidewall baseboard

Hand injection of foaminto wall

Advantages of a Typical Chemical Treatment

1. Termites are not repelled by a typical insecticide barrier such as Termidor or Premise.2. They pick up the chemical without detecting it and carry it back to the nest.3. At the nest it is fed to the other workers and the queen.4. Chemical treatments are less expensive than baits. 5. Chemical treatments are proven to last 5 years.

Disadvantages of a Chemical Treatment

1. Environmental impact?2. Tends to be invasive with the hole drilling.

Termite BaitsExterra – diflubenzuron (chitin synthesis inhibitor)Recruit II – hexaflumuron Subterfuge – hydramethylnon (can be placed inground without monitoring – check at one monthand then every three months.Firstline - sulfuramid (intended for above ground)Firstline GT – in ground in specific areasAdvanced Compressed Termite Bait – has a TICon top (diflubenzuron)

Sentricon (DowElanco)

Bait tubes are placed in the ground every 10 feet around the structure to attract foraging termites

Termites consume bait, take it back to the colony, and share food with other termites in the colony

The bait affects the growth and development of termites resulting in termite colony collapse

Sentricon

First Line (FMC)

Bait stations placed in areas where termites are known to be present

Termites feed on bait and feed it to other termites at the colony

The active ingredient is a slow acting stomach poison--direct kill of termites in the colony

Advantages Of Termite Baits

Reduce insecticide usage-- reduce environmental impact

Selective toward termites

Control can be achieved without ever entering the home

Disadvantages Of Termite Baits

No guarantee that termites will feed on bait

More costly than conventional chemical treatment

May require up to a year or longer to gain control

Borate Treatments

Commercially available as Tim-Bor and Bora-Care ( contains boric acid)

Apply liquid sprays directly onto unfinished wood for prevention and control of termites

Boric acid penetrates into the wood and is available for consumption by termites

Other Control Options

* Product not available yet in Florida

Bio-Blast-- spot treatment with parasitic fungi

Insecticide impregnated vapor barrier *

Stainless steel mesh

Sand Barriers

Drywood Termites

Live in dry, sound woodRequire much less moisture than subterranean termites-- do not need to return to the soil for moistureMay infest structural wood as well as furniture

Drywood Termites

Drywood TermiteDamage

Clean, smooth galleries in both spring and summer woodTermites may eat across or with the grain of the woodDo not construct mud tunnelsNot as damaging as subterranean termites

Signs of Infestation

Dry, hard fecal pellets present in galleries or in small piles around infestation

Presence of winged reproductives

Presence of shed wings around window sills, ect...

Identification of Drywood Termites

1. Character of reproductives. a. wing venation b. antennal segments

2. Character of soldiers. a. shape of head. b. mandibles.

3. Presence of fecal pellets.

Drywood Termite PreventionPrevent Swarming Termites From Entering

Exclusion by sealing entry pointsSeal roof vents with screenCaulk cracks and joints

Painting wood surfaces on exterior

Pressure treated lumber

Drywood Termite Treatment Options

Treatment Unit of Coverage Time per UnitFumigation Entire structure 1-2 days

HeatSeveral rooms, attic,

apartment4-12 hours

ColdWall voids between

studs30 min

Electrocution 3-4 ft. of board 2-30 min

Microwaves 1-4 ft. of board 10-30 min

Drill-and-Inject 3-12 ft. of termite gallery 5-20 min

Borate Surface Spray

Raw wood surfaces 10 min-2 hours

Wood Replacement

Remove wood member Highly variable

Fumigation

"Tent the house" -- must vacate structure for at least 24 hours

Very effective-- kills all termites in structure

Does not prevent reinfestation

Heat Treatment

Blow hot air into structure through ducts (150 F for one hour)

Must consider heat sensitive items in building

Very expensive-- does not prevent reinfestation

Cold Treatment

Liquid nitrogen is pumped into walls or voids in walls to kill termites

Limited use and mixed results

May damage pipes and wall coverings

Electro-Gun and Microwaves

Microwaves "cook" the termitesrequires heavy, clumsy equipment limited to spot treatment

Electro-Gun uses high voltage to "fry" termites

poor penetration into wood efficacy?

Conclusions About Termites

Termites are source of much concern to Florida residents

Homeowner can assist by understanding:the basic biology of termites their role in preventiontheir control options

Authors: Jerry E. Gahlhoff, Jr.,University of Florida

Photos: University of Florida

Edited by David Shibles, Polk County Extension

Entomology And Nematology Department

Copyright University of Florida 2000

For more detailed information see the Featured Creatures WWW site at

http://creatures.ifas.ufl.edu/