These creatures do an enormous amount of damage to tender plant foliage, young shoots of delphiniums, pyrethrums and lupins being particularly favoured. The eggs are laid during summer in clusters under garden rubbish or in the soil. They are mainly night feeders and hide during the daytime in any place which is dark and moist, e.g. beneath, stones, , boards. Snails usually on the surface, e.g. at the base of the winter-flowering unguicularis (stylosa), a favourite haunt, but slugs often work underground, eating , bulbs, corms and tubers. One species known as the subterranean slug does serious damage to potato tubers in Lancashire and the Lothians. Slugs are generally less troublesome on light, sandy soils which dry out rapidly. In cool districts and on heavy, damp soils they are more abundant. Note that these pests can excrete a slime which often enables them to get rid of insecticides designed to kill (this is particularly noticeable where very light dressings have been given).
Where slugs and snails have really gained a foothold in a garden, control is often difficult, although they can eventually be eradicated if one persists with the treatment. Alum, dry Bordeaux powder, copper sulphate, lime, salt, soot, naphthalene are among the substances used to control these pests, but metaldehyde is now recognized as the most efficient material and in Scotland as many as 12,000 slugs per acre have been destroyed using this substance, which is available from all seedsmen etc. Note that acid soils seem to harbour more slugs than alkaline land. Liming will therefore help a little towards reducing their numbers. Snails are often more readily found in dry weather and tend to assemble in. clusters.