Within
a termite nest there are members of different castes, each with a different
role to perform and all interdependent upon each other for survival of the
colony. These include the queen, king, the winged reproductive (young kings
and queens), soldier and worker termites.
The king, queen and worker termites. |
Worker termites - thin external skin. |
|
The queen termite is an egg laying machine; her body is enormous
compared to her off-spring; she can live more than 25 years and produce
more that 2,000 eggs a day. |
|
The king and queen live in a central chamber and are tended by
the workers. |
The workers are by far the largest
caste in the eastern subterranean termite colony and
the one that does the damage; they are a creamy translucent colour,
soft bodied and carry out all work in the nest, including gathering
food (timber and other cellulose); constructing tunnels; repairing
and enlarging the colony nest; grooming each other and feeding the
soldiers, the king, queen and also caring for the young nymphs until
mature.
IDENTIFICATION: Eastern subterranean worker termites are small in
size, about half the size of match-head or 1/8" long and are soft
bodied insects. They have no wings, are sterile, blind and work 24
hours a day for their entire 2 year life span. |
The soldiers are the defenders of the
colony, particularly against marauding ants - with whom they have
engaged in a relentless war lasting 250 million years.
IDENTIFICATION: the soldiers have an orange coloured rectangular armoured
head with mandibulate pinchers which they use to crush the ants. On
their forehead is a fontanelle (frontal gland pore) used to emit a
sticky latex to ensnare the ants. Its mandibles are curved at about
70~90 degrees. The body of the Eastern subterranean termite is flat
and almost as wide as the head, with the width of approx 1/32”.
The soldier termite is usually the first to be seen in large numbers
when any active termite workings (mud shelter tubes or damaged timber)
are opened. Soldier termites will rush out to guard the opening whilst
worker termites repair the breach. |
The swarmers (reproductives) are
called "alates"
and are commonly seen when they swarm during daylight; they have eyes;
are poor fliers but are swept along by the wind; they land, drop their
wings, find a mate to become king and queen of a new termite colony.
IDENTIFICATION: The eastern subteranean termite swarmers are about
3/8" long (including wings) with a dark brown body and a small
fontanelle (frontal gland pore) on its head. Their wings are brownish
grey with two dark solid veins along the forefront of the front wings.
The front wing is distinctly larger than hind wing.
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. The swarmers are emitted in their thousands
when a mature termite nest is large and well established.
Eastern subterranean termites swarm in large numbers over a wide area
to find a mate from another colony nest to start up a new colony.
A suitable location for nesting should provide moisture and a readily
available timber food source close by.
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. The swarmers are emitted in their
thousands when a mature termite nest is large and well established.
Swarmers are usually produced after this period and are an indication
a large termite nest is in the vicinity, a sure danger sign and a
warning that professional protection is required.
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.
|
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.
|
|
Eastern subterranean termites symbiotic digestive
system |
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.
|
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.
|
Eastern subterranean termites need to maintain a high level
of humidity and temperature (75 to 95F) 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. |
|
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. |