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Hydrangea Scale


Hydrangea Scale

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Caused By:-     The Scale insect Pulvinaria hydrangeae


This sap sucking scale insect also attacks other trees such as Prunus and Acer. The scale insects are most noticed in the early spring when the female lays the eggs under the leaves amongst a mass of white cottony waxy fibers. The egg masses are oval, up to 5mm long and there can be many(15+) under one leaf. The eggs hatch in summer and the flat yellowish larvae or nymphs settle down to feed near a leaf vein. In the Autumn they move to the bark and overwinter as immature nymphs. As with many scale species they can excrete honeydew, which attracts ants and encourages the growth of sooty mould on infested foliage. the infestation does not usually kill the plant, but weakens it for the next years flowers and growth and leaves the shrub less able to ward off other pests attack.
See these other Scale insects Azalea Bark, Azalea Cottony, Beech Bark, Brown, Eucalyptus Gumtree, Euonymus Mussel, Hemispherical, Horse Chestnut, Juniper, Mussel, Oleander, San Jose, Scale, Soft, Viburnum Cushion, Wisteria, Wooly Vine.


The best way to deal with them is to spray with an insecticide in early summer when the young nymphs are more prone to the effects of the insecticide. A combination of knock down and systemic insecticide works best. Spraying with insecticidal soap in summer and tree oils in winter is another option. These pests only produce one generation a year so you could get rid of them for good in one year.

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