Woodlice are very common harmless insects. The adults are about 15mm long and slate grey in colour. They are very flat and can roll into a tight ball if disturbed. Many types of woodlice are found in the garden and can be seen beneath stones, flowerpots and other types of cover. They usually come indoors during the cold weather, attracted by vegetation and niches outside. A female can produce up to 150 eggs, which she carries on her body in a pouch. A young wood louse is white and only about 2mm long. It may take up to a year for a wood louse to reach the adult stage.