Woodlice

Adult woodlice are slate grey in colour, have 7 pairs of legs and are between 2.5 to 18mm long. They are crustaceans and are closely related to crabs and lobsters. They evolved to live on land but still need damp conditions in order to survive.

Woodlice avoid light and are active at night, feeding mainly on dead or decaying plant material. By day, they are usually found hiding under stones, plant debris or damp wood. In autumn however they may enter homes through air vents or under doors in search of shelter for the winter.

Woodlice do not harm people or damage buildings but can still be a nuisance.

How do they live?

The female lays eggs in a pouch underneath her body. After about three weeks, the eggs hatch and young woodlice emerge. The young look like smaller versions of the adults and regularly shed their shells as they grow.

In the UK Woodlice breed during the summer months only, producing between six to two hundred young in a season and have a lifespan of between one and four years.

Can I treat them?

Woodlice gather in large numbers in dark, damp places, such as under decaying wood or plant debris. Removing potential sheltering places away from your home can help stop woodlice from entering your house.

You can apply a barrier treatment using a suitable insecticide that has been cleared for use against wood lice.  These can be in spray or powder form that is applied to the outside walls of your home. Make sure you treat any small cracks and gaps there may be and in particular the gaps around steps air vents and any damp areas

Please read the label and follow the instructions on any insecticide you use and look specifically for any additional measures you may need to take in respect of children and animals.

Insect Drawings © Bayer 1964