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Soft Scale Insect


Soft Scale Insect

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Caused By:-     The Scale Insect Coccus hesperidum


There are many kinds of Scale Insects all are specialised, limpet-like, immobile insects attached to some part of a host from which they suck the sap often exuding the sap sugars called honeydew. This honeydew then attracts other insects like ants and bees and can lead to sooty mould being formed. Ants then protect the scale insects from their predators so they can farm the honeydew.
The main families of scale insects are:- Asterolecaniidae(pit scales), Coccidae(soft scales), Dactylopiidae(cochineal), Diaspididae(armored scales), Eriococcidae(felted scales), Kerriidae(lac scales), Margarodidae(cottony cushion scales, giant coccids and ground pearls), Pseudococcidae(mealybugs).
Soft Scales Insects are members of the Coccidae family which have relatively soft-bodied compared to most other scales insects. Soft scales protect themselves by producing a waxy substance which cover their bodies. This waxy material becomes stuck to the insects and protects them from insecticides. Some common soft scales are the Wax scale, Oak Lecanium scale, Cottony Maple Leaf scale and the Tulip Tree scale.
The spread of Soft Scale insects is by the first stage nymph that hatches from the egg. This stage is called a “crawler,” because usually it is the only stage of soft scales that has legs which enables them to move.
Soft Scales on outdoor plants usually have one generation a year and in most species the eggs hatch from June to July. Indoors they reproduce all year round.
Spraying is more effective against the newly hatched nymphs.
The eggs are produced under the insects waxy shell which protects them as they overwinter.
Coccus hesperidium, Picture by Whitney Cranshaw, Colorado State University,
See these other Scale insects Azalea Bark, Azalea Cottony, Beech Bark, Brown, Eucalyptus Gumtree, Euonymus Mussel, Hemispherical, Horse Chestnut, Hydrangea, Juniper, Mussel, Oleander, San Jose, Scale, Viburnum Cushion, Wisteria, Wooly Vine.


In warm environments biological control can be used in greenhouses with a parasitic wasp, Metaphycus helvolus. This attacks two species of scale insect, soft scale (Coccus hesperidum) and hemisperical scale (Saisettia coffeae). The parasitic wasp is available from some mail order suppliers of biological controls methods.
The shell or scale protects the older insects from insecticides, so spraying is only effective against the newly hatched nymphs. With scales on outdoor plants there is usually one generation a year and in most species the eggs hatch from June to July.
Scales insects in greenhouses or on houseplants breed throughout the year so all stages in the life cycle may be present at the same time.
Scale insects can remain attached to the plant long after they are dead but new growth should be free of scales once they have been brought under control.
Systemic insecticide is best as the outer scale usually protects the insects inside.
Horticultural oils, insecticidal soaps and systemic insecticidal soil drenches can be used to control soft scales.
Brushing of the insects with methylated spirits can be tried or if the infestation is light picking off the individual insects along with keeping an eye out for young hatchings.
Blasting outdoor plants with a strong jet of water might work on sturdy plants or trees.

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