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/