These are also very common pests of cacti and succulents, but are found only on the roots of infested plants where they do considerable damage. This may lead to the plant rotting where the damage allows fungal or bacterial infections to enter the plant tissues. They produce powdery white or white fluffy deposits in the soil which may sometimes also be seen underneath the pot. Their general appearance is reminiscent of tiny pinkish-brown woodlice (2-3 mm long) in the soil and roots.

Control of root mealy bugs

Use regular applications (weekly for several weeks) of insecticide (read the label to find pests controlled, use and precautions) watered into the soil, or immerse the plant pot up to the top of the soil in a bucket of insecticide with a couple of drops of washing-up liquid to help wetting of the soil. The plant will need to be carefully dried out after a soaking, especially if treatment must be carried out in cold weather.
As a preventative measure, ground up moth balls added to the potting mix seem to discourage infestation by root mealy bug, and probably discourages other insects. However, the chemicals in the moth balls can cause damage to plastic plant pots and are best used with clay pots. ( NB. In the UK, chemicals must be used only as directed on the label: other use could be considered an offence. ) Root mealy bugs also seem to prefer peat-based mixtures to soil-based composts, although not exclusively.