With a relatively dry hot summer here in Brisbane we are noticing a scale infestation on indoor plants and ornamental vegetation.
Plants infested with scale can have a dirty black or brown appearance and leaves can look withered and unhealthy.
Generally scale insects are small domed sap sucking insects, which look like an inanimate black, brown or white lump. They settle on plants that are struggling or stressed, exuding a honeydew secretion that can lead to a fungus sooty mould or ant infestation. Eventually, blocking sunlight from reaching the leaf and inhibiting growth.
Removal is best by physically wiping the plant (or removing infected branches) and scrub with soap (like Sunlight soap) as a safe and effective alternative to spraying with chemical products ('Yates Scale Gun' are also designed for the control of scale bugs). Spray with neem oil after the soapy rub down.