Many people, it is said, find raw cucumber indigestible. Fortunately slugs and snails do not. A correspondent of a columnist in The Country-man noticed that slugs were attracted to rejected pieces of cucumber in his compost heap, and having a constant glut of cucumber, he cut more slices and laid them as bait on his concrete path. When he went out at dusk to check, he would generally find about half a dozen around each slice.
Later on the same night, revisiting the cucumber, he found about 20 more slugs, all of two common species - the garden slug and the field slug. And they were feeding on the corpses of the slugs which our friend had killed on his first round. The cucumber slices, had already been consumed. Some people, says the writer, prefer not to kill anything that moves and keep off the slugs and snails by surrounding their plants with ash. Ash? Of what? From wood fires, it might work. But who has coal ash? And turf ash probably absorbs damp too easily. Why not try some very sharp grit? It's not always easy to get, but it works.
Some of the people who don't like to kill, says the writer, put their trust in hedgehogs and thrushes. An idealist, or he knows someone who breeds hedgehogs. Certainly nothing can beat them. But you'd need two, wouldn't you? A male and a female, and then, as they bred, if you had a walled, enclosed garden, you can surprise your friend with a pair of hedgehogs as a Christmas present.
Collin's pocket-size Garden Wild Life gives exhaustive coverage of slugs and snails - not only their feeding habits but also their sex-life. Take the Great Grey Slug, for example (harmless in the garden, by the way). After meeting on the ground, they climb up some vertical surface and lower themselves on a rope of mucus. Their "shiny white genitalia entwined (as shown in the picture)". The whole process may take up to an hour. One drops to the ground, while the other climbs up the rope and eats it as it goes. Both lay eggs, for they are, in common with other garden slugs and snails, "hermaphrodite and each individual contains both female and male organs".
The Garden Snail, with its black and tan shell, is probably the most damage-inflicting of all. "Few low-growing plants escape the attentions of this abundant pest". You know that.