Snails are in many respects the same as slugs as far as gardeners are concerned. The main difference - visually - is the fact that a snail ahs a shell, and therefore tend to do most damage above ground. (It would be rather difficult to drag your house through a small gap to get at an underground tuber!)
However, there is one basic difference between slugs and snails that might be important for gardeners in certain areas. Snails tend to live in areas that are alkaline - Chalk or Lime in the soil, which is used by the snail to make its shell (Not many people know that!)
The damage caused to plants by snails is much the same as that caused by slugs, and the control is also similar - ie slug pellets, beer traps and the like - see here. Snails are a little easier to pick up without getting that disgusting mess over your fingers. The problem is, what to do with your snail once you have 'captured' it.
Be aware that snails are thought to have a 'homing' instinct, so simply throwing over the fence does not work in the long term!
The common garden snail - helix aspersa having a meal of parsley!
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