PLANT PROTECTION 1 – Pests, Diseases and Weeds

PLANT PROTECTION 1 – Pests, Diseases and Weeds
LIST OF SOME
SPECIES
(contd)
Many other
genera/species
Not established
in Australia
COMMON NAME SCIENTIFIC NAME HOST RANGE
(not exhaustive)
DAMPWOOD TERMITES
Nests are small; there may be separate and independent colonies in stumps, rotting
logs or rot pockets in dead or living trees and timber that has a high moisture content.
Often no contact with soil. Rambling tunnels in damp wood.
Dampwood termite Porotermes adamsoni Living trees, mainly eucalypts,
other trees, poles, occasionally
houses. Rarely infests small
diameter trees
Ringant termite
DRYWOOD TERMITES
Neotermes insularis
Largest termite species in
Australia up to 15 mm long.
Colonies in branches and stubs of
wood of living trees, especially
eucalypts. Serious pest of forests
of the east coast of Australia
Nests are small and independent groups in dead branch stubs, stumps, poles on
ground. Attack either dead wood in trees or dry wood in service in houses.
Moisture. They require only the moisture of the atmosphere and of the dry timber in
which they occur. They obtain water from the wood in which they live and have no
contact with the soil, or any other source of moisture.
Rambling galleries in dry wood, They occur in warm tropical areas and in dry areas
of subtropical Australia.
Drywood termites Cryptotermes spp. Furniture, structural timber,
dead wood in trees and poles
West Indian Cryptotermes brevis
drywood termite
BENEFICIAL ACTIVITIES OF TERMITES
RECYCLING OF NUTRIENTS
Buildings, furniture. The world’s
most destructive termite species
Termites play a prominent part in the recycling of plant nutrients through the
disintegration and decomposition of dead wood, plant debris, fungi and animal
droppings. Most termite species eat grass and other surface vegetation and have an
important role in maintaining soil fertility and aeration. Many convert dead trees and
other plant material to organic matter and minerals. They may search for food in the
open on humid nights.
Termite galleries improve soil structure, water entry and storage in soil.
HABITATS FOR WILDLIFE
The excavation of termites alters the structure of trees and provides habitat
spaces for bats, birds, reptiles, etc.
Lace monitors (tree goannas) lay eggs in termite mounds in eastern Australia
which are perfect incubators. After the eggs are laid, the termites quickly repair the
damage imprisoning and protecting the monitor eggs inside the mound for 9
months. Adult monitors return at precisely the right time to dig an escape tunnel for
the hatchlings. Termites pay a heavy price as the effort to re-build their nests year
after year is extraordinary and in some occasions the termite colony may die.
FOOD CHAIN
Termites are an important component of the food chain of many animals, eg birds,
lizards, echidnas, spiders and predatory insects.
DIDJERIDOO
When termites hollow out the center of a log many channels and irregularities are
formed. It is this that alters the resonance of the didgeridoo creating the unique
sound that is distinctive of Aborigine Australian culture.
Fig. 117. Termites. Upper left: Termite galleries on a
timber pole; galleries tend to follow cracks in the wood.
Lower: Small termite mound (Nasutitermes exitiosis).
Portion removed to show internal structure. PhotoNSW Dept of
Industry and Investment.
Fig. 118. Timber damaged by termites. Paper thin
.
PhotoNSW
Dept of Industry and Investment (E.H.Zeck).
176 Insects and allied pests - Isoptera (termites, ‘white ants’)