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Destructive Termites in Florida |
Identification of the main destructive species |
It is critical to identify the species of destructive termites to formulate
an appropriate control program. The main species of destructive
termites in Florida are:
CONTENTS: learn about destructive species of termites - tips on identification
of the timber damage - find out when they swarm in your
local area and how to identify the swarmers, workers and soldiers - learn
about their fascinating biology, life-cycle and behavioural aspects - and receive
professional tips on how best to protect your home from the world's best timber
recycler .... subterranean termites. |
Eastern
subterranean termites
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Identification of Timber Damage
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Eastern subterranean termites are highly destructive to douglas fir and
other common building timbers widely used in the construction of homes in
Florida. In large numbers, the subterranean worker termite will rapidly
devour the internal spring wood sections; preferring to leave the harder
summer wood sections.
As a result, infested timbers are often left as a thin external shell, with
layered "honey-comb" hollow sections (as illustrated) packed with moist
soil. Eastern subterranean termites thrive in a moist dark environment.
Moisture and humidity control are essential for their survival. |
Destructive nature of Eastern
subterranean termites
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The Eastern subterranean termite is a serious economic timber pest causing
millions of dollars of damage throughout Florida. It is estimated that more
than 1 in 5 homes in the urban areas of most Florida cities have been or
will be attacked at sometime by these voracious little insects. |
The life-cycle
of subterranean termites
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Biology of Eastern subterranean
termites
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Eastern subterranean termites are a highly social insect centred around a primary breeding nest. The colony consists of several general castes, each with a different role to perform, and interdependent upon each other for their survival... the queen, king, the winged reproductives (young
kings and queens), soldiers and the destructive workers.
Queen, King and attendant Workers |
Worker Termites - do all the damage |
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THE QUEEN TERMITE
is an egg laying machine, her body is enormous compared to her off-spring
and she can live more than 25 years and produce more than 2,000 eggs
a day. |
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THE KING
and queen live in a central chamber and are feed and attended to by
the worker termites. |
WORKER
termites are by far the largest caste in the eastern
subterranean termite colony and
the one that does all the damage. They carry out all work in the nest,
including gathering food (timber and other cellulose), constructing
tunnels, repairing and enlarging the colony nest, grooming and feeding
the soldiers, the king, queen and young nymphs in the nursery.
IDENTIFICATION: Eastern subterranean worker termites are small in
size, about half the size of match-head or 1/8" long. They are a creamy
translucent colour, soft bodied, have no wings, are sterile, blind
and work 24 hours a day for their entire adult life-span. |
SOLDIER termites
are the defenders of the colony, particularly against marauding ants
- with whom they have been at war for more than 250 million years.
IDENTIFICATION: the soldier termite has an orange coloured, rectangular
armoured head, with mandibulate pinchers which they use to crush the
ants. On their forehead is a fontanelle (frontal gland hole) used
to squirt a sticky latex to ensnare the ants. The soldier's mandible
pincers are curved at about 70 to 90 degrees. The body of the Eastern
subterranean termite is flat, with the width of approx 1/32”.
CONSUMER NOTE: If you open termite
infested timbers or their mud tunnels or shelter tubes, it is the
soldier termites that rush out to guard the area whilst the workers
repair the breach. The identification of these insects as "termites"
means an immediate professional inspection and protective measures
are essential to avoid further ongoing or extensive damage. Remember:
the standard home insurance policy in Florida, does NOT cover the
costs of repairs or replacement of termite infested timbers in a home.
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SWARMERS
or REPRODUCTIVE termites - scientifically called "alates"
are commonly seen by homeowners in Florida, when they swarm in large
numbers, generally in the spring, during daylight. They have eyes,
are poor fliers but can be swept hundreds of yards, by the wind. When
they land, they drop their wings, find a mate to become king and queen
of a new termite colony.
IDENTIFICATION: Eastern subteranean
termite "swarmers" are about 3/8" in length, including wings. They have a
dark brown body and a small fontanelle (frontal opening) on it's
head. Their wings are a brownish grey, with two dark solid veins along
the forefront of the front wings, which are distinctly larger
than hind wings.
WHEN DO THEY SWARM?
In the northern part of their range, swarming takes place in the spring,
but without rain. In the southern areas, swarming usually follows
rain. Occasionally, a few smaller swarms may occur during the summer.
Swarming most often occurs during the morning following a warm rain
shower whereby the soil temperature is around 70°F. The swarmers
are emitted in their thousands when a mature termite nest is large
and well established.
CONSUMER NOTE: If you find swarmer
termites in or around your home, it is a sure sign a large nest is
close by and that your home is at high risk of a termite infestation.
Colony nest development is slow in the first few months, with the
egg-laying capacity of the new queen termite peaking after a few years,
producing up to 10,000 offspring a year. The queen may live for many
years and workers up to two years.
Several years are required
before the termite colony reaches the typically mature size. In some
locations an Eastern subterranean termite colony can contain several
million termites foraging over a wide area (up to 12,000 square feet)
and actively feeding on trees and freestanding poles as well as buildings
and other timber structures.
The colony nests of Eastern
subterranean termites are usually located in the ground below the
frost line, but above the water table. Mud galleries or "shelter
tubes" are constructed across hard objects in order to gain access
to timber food sources.
Eastern subterranean termites
constantly search for new food sources. They are known to enter buildings
through cracks in concrete flooring or to travel under parquetry or
tile flooring through gaps of less than 1/16" wide.
Where moisture regularly
collects inside the wall or other cavities of a building, say from
faulty plumbing or broken roof tiles, the Eastern subterranean termite
can develop a subsidiary colony nest which may not require contact
with the ground to ensure it's survival. |
They build a central colony nest from
which they construct underground tunnels that radiate within a 100 yard
radius from a central colony nest in search of a timber (cellulose) food
source.
The picture on the left shows a termite inspector examining
an above ground termite subsidiary nest built inside a wall
cavity of a home.
Termites often build such nests if moisture is allowed to regularly
collects inside the wall cavity, say from leaking pipes, shower
recess, faulty plumbing, guttering, broken roof tiles, etc.
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Termites
travel in humidified mud-shelter tubes or galleries...
The picture on the left shows a mud shelter tube that subterranean
termites have constructed over a solid object, in this case,
a brick foundation wall in the sub-floor of a cottage.
Subterranean termites travel in these mud shelter tubes as protection
from predators, sun-burn, dehydration and to maintain a high
humidity environment which is essential for their survival.
Eastern subterranean termites are highly
secretive, preferring to enter a building through areas inaccessible
to inspection, such as, through in-fill patios, fire heaths,
expansion joints and cracks in concrete slab (on-ground) flooring.
Eastern subterranean termites can pass through a 1/8" crack
or an expansion joint (eating through the rubber compound) between
adjoining concrete on ground flooring. They can also travel
under parquetry and floor tiles to get to the wall framing timbers.
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Eastern subterranean termites
symbiotic digestive system
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Only the worker termite caste can digest timber by the use of symbiotic
protozoa in their gut. Worker termites feed their partly digested semi-liquid
food, regurgitated from their mouth or passing from their anus, to the other
termites, a process known as trophallaxis.
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Eastern subterranean termites have a well ordered social system with
amazing engineering capabilities and an acute survival instinct; they
obtain moisture from the soil and moist decaying timber, and communicate
using pheromone signals.
The mutual feeding, constant grooming and close
social habits of termites are used to advantage in modern termite
control baiting systems. |
Certain hi-tech termite baits are now on the market that have a delayed
lethal effect on termites which readily pass on the bait to other termites
in the central colony nest during the mutual grooming and feeding.
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Eastern subterranean termites need to maintain a high level of humidity
and temperature (75 to 95°F) in their central colony nest.
Eastern subterranean termites eat through the centre of susceptible
timbers leaving nothing but a thin veneer of timber and/or paint.
They will pack mud in cracks and joints in timber to prevent loss
of humidity and resultant dehydration. |
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As noted above, termites constantly groom and feed each other. A valuable
technique for the termite controller is to instal and monitor a termite
baiting system next to any live activity found in and around the premises
where termite foraging is most likely to occur. Subsequent inspections (preferably
monthly) may reveal dead or sick worker termites, they change colour to
a mottle look, and spread of the termite bait to other termites leading
to elimination of the colony.
The termite baits are designed to be non-repellant to the termites and has
a unique delayed effect. Time enough to be passed onto the other termites
in the colony including the queen, with a sufficient dosage leading to the
elimination of the entire colony. This process is explained in detail in
the Termite Control
section of this website. |
If you find these termites do NOT disturb them
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Eastern subterranean termites have acute survival instincts. If they
are shaken up or disturbed, the termites often will abandon the associated
area and move on to secretly
cause damage in other areas in the building. If you find eastern
subterranean termites in or around your property, it is essential that you
do NOT disturb them and promptly arrange for a professional inspection and
application of a termite bait to the live termites, if present in abundance.
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Subterranean
Termites...
Mother Nature's most prolific builders
This picture shows a large above ground termite nest found in
the Northern Territory of Australia. In the USA, most of the destructive
subterranean termite species build their nest completely below
ground level. A large Eastern subterranean colony in an urban
environment in Florida is most often unseen, until a serious problem
is encountered.
Modern termite control methods include termite baiting systems;
the installation of a treated soil barrier or eradication zone around
the base of a building; and a range of cultural and home maintenance
measures to make your home less susceptible to subterranean termite
infestation.
Find Out
How to Protect Your Home
Click on ... Termite
Control
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Powderpost
drywood termites |
Area of Distribution: Cryptotermes drywood termites are found mainly in
the humid coastal areas of the southern states of the United States from
Virginia to Florida, through the desert southwest, along the Pacific coast
to northern California and in Hawaii.
Cryptotermes drywood termites are sometimes discovered in other states
after being transported in furniture or other timbers.
Cryptotermes drywood termites infest the structural timbers of buildings,
furniture and other dry timbers having less than 12% timber moisture content.
This termite species require no ground contact and obtain their required
moisture intake from the timber they infest.
Cryptotermes drywood termites are sometimes called "powderpost"
termites or "furniture" termites due to their small faecal droppings
and the fact that they commonly attack timber furniture. The average moisture
content of seasoned timbers in service in the United States is 8-12%,
except along the coastal plains where the moisture level can exceed 12%.
Identification of Swarmers and Soldiers: Swarmers are about 7/16-1/2"
long including the wings, with the head width being 1/32-1/16". The
head and body are pale yellowish brown to pale reddish brown and the wings
are hardened and pigmented. The veins are pale yellowish brown in the
outer half of the wing.
The front wings have 3 dark, heavily sclerotized veins in the front half
of the wing. The median vein is un-sclerotized and runs midway between
sclerotized veins above and unsclerotized area below. The area ends near
the wing tip even if branched along its length and is not hairy. The tibia
have spines lacking along their length, apex has 3 spines.
The head of the Cryptotermes drywood termite soldier is short and thick
in front, the front surrounded by a flange and the front part nearly black.
Mandibles re-curved under front of head, with an unequal number of teeth
on each member of pair. The tibia lacks spines along length.
Identification of Timber Damage: The most obvious sign of infestation
is the piles of tiny faecal pellets ejected through temporary holes in
the infested timber. The faecal pellets are hard, elongated and oval with
rounded ends, and have six concave sides.
Cryptotermes drywood termites eat across the wood grain and make chambers
or galleries connected by tunnels. Other signs of infestation include
the presence of swarmers or their shed wings, piles of faecal pellets,
termite plugs which seal all openings in infested wood, and surface blisters
caused by older enlarged galleries very close to the wood surface. Occasionally
they may build shelter tubes constructed of pellets cemented together
to bridge over to an adjacent piece of wood.
Biology and Habits: Cryptotermes drywood termites do not live in the ground.
They obtain all the moisture required from the timber they infest. They
do not require contact with the ground and do not build mud shelter tubes.
Their colonies are located in the wood they eat and are small in size,
containing perhaps a few thousand termites. It is commonplace to have
multiple colonies in the same building.
Cryptotermes drywood termite infestations tend to be localised in buildings,
in doors, window trims, fascias, even picture frames. They eat the springwood
as well as the summerwood. The cavities they excavate in timbers are clean
and smooth, and do not contain any mud packing, in contrast with subterranean
termites.
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Florida
dampwood termites |
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Neotermes castaneus |
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Neotermes connexus |
Area of Distribution: Neotermes species are found in Florida, Hawaii,
Puerto Rico, and the Virgin Islands. The three Neotermes species in Florida
have various extended distributions that include the Bahamas, Cuba, and
Mexico.
Neotermes are common in the subtropical woodlands, mangrove forests, and
urban settings of the coastal peninsula of Florida and the Florida Keys.
Neotermes castaneus has the greatest distribution in Florida with its
northern limits extending to Merritt Island on the eastern coast and Pinellas
County on the Gulf coast. Inland infestations of Neotermes castaneus have
been confirmed in Orlando and along the shore of Lake Okeechobee.
The range of Neotermes jouteli extends from Vero Beach to the Keys, while
Neotermes luykxi, a relatively newly discovered species, has been collected
from eastern Broward County to Key Largo.
Identification of Swarmers and Soldiers: Alates leave
mature colonies via multiple dispersal flights over "swarming"
seasons that can last for several months.
Neotermes jouteli and Neotermes luykxi tend to disperse in the late spring
or summer, while Neotermes castaneus has peak flights in the late fall
or early winter. Flights occur at dusk or at night.
Dampwood termites are relatively strong fliers and, like most nocturnal
flying insects, are attracted to lights. Porch lights, indoor lights,
and video monitors often lure the alates inside, especially when doors
and unscreened windows are opened. When alates are found indoors, their
origin is usually from a yard tree or a woodland colony.
Occasionally, alates found indoors originate from an infestation in the
structure itself. However, alates flying indoors are unlikely to find
the moist wood they need for successful colonization, and are doomed.
A month or two before dispersal flights, nymphs with long wing buds appear
and gradually molt into swarmers (alates). Neotermes swarmers are large
and have two pairs of wings that are lightly creased along their vein
paths.
Fore wings and hind wings are about equal in size and shape. Each fore
wing has five pigmented and enlarged veins near where they attach to the
body. The enlarged median vein distinguishes Neotermes swarmers from all
other termites in Florida.
Neotermes soldiers from the same colony can differ substantially in size,
but all are large (1/3” - 1/2" long) and have at least two
marginal teeth visible on their left mandibles. They differ from other
termites in Florida in that their pronotum is as wide as the head and,
at the same time, the width of the pronotum is much greater than its length.
Identification of Timber Damage: The limited conditions that support colonization
by dampwood termites relegate these termites to minor pest status. Wood
damage, however, can be severe after several years if infestations are
left alone.
Damage to trees and branches may cause weakening but does not appear to
harm tree viability although hollowing from galleries might promote secondary
fungal intrusion. These termites build networks of galleries that meander
through the wood in which they are hidden.
Biology and Habits: Neotermes castaneus, in particular, prefers to nest
in living trees. Colonies are often discovered in trees when they are
pruned or damaged by windstorms.
Robust colonies of N. castaneus apparently live in trees and palms for
years or even decades before they are discovered. In one case, alates
of N. castaneus were emerging from a Ficus tree in an indoor shopping
mall in New Jersey many years after the tree was delivered from Florida.
Although the galleries may weaken trunks and branches, the overall health
of the tree is usually not directly affected. The termites appear to limit
their feeding to the dead xylem tissues while avoiding the cambium.
Because of their moisture requirements, structural infestations of dampwood
termites are associated with sources of free water. These include wood-to-soil
contact, wood exposed to roof leaks, or wooden siding or ornamentation
exposed to rainfall or sprinkler irrigation.
Because these same conditions are conducive to fungal decay and subterranean
termites, it is in the interest of the property owner to correct these
moist conditions.
Neotermes infestations can extend into sound dry wood several yards away
from the moisture source, but once the remote source of moisture is removed,
the colony will gradually decline and succumb to desiccation.
Like drywood termites, dampwood termites produce faecal pellets, but because
of the moist conditions of the gallery system, the pellets loose their
distinctive shape and form amorphous clumps or paste. The degree of shape
degradation is directly related to moisture content.
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Published by Fumapest Group © copyright 1995
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