hy do you need to? They don't do any harm, they actually live off debris in damp corners or under conainers! I leave them be....they aren't a menace like snails or slugs.

Spritzhenry, they do sometimes eat tiny seedlings, though my experience leads me to blame crickets before woodlice for that.

They have got to be in huge numbers and very hungry to attack green plant material (leastways the ones in Britain). Clean out the places they like to hide, they need damp and dark spots. Sprinkle talcum powder, they hate the dryness of it. But as said, they are actually useful little critters, in the right place.

I leave woodlice alone to do their job of eating up rotting bits and pieces, they in turn become food for frogs, toads, chickens and other birds. If you get rid of the woodlice you are less likely to see other birds etc.