Slugs and snails are two different animals!
Those days when we were still in school, I remembered we had read text books about snails but not slugs. We saw no slugs in Singapore, but snails. We did not pay too much attention to these small animals because we did not see them often. However, these days we see them almost everyday.
According to our handsome Science teacher during our old schooling days:
snails belong to the great group of animals (sub-kingdom) known as the
Mollusca. The molluscs are primarily water animals, many of them have
been taken to the land; and snails and slugs may be found active in
Snails are found both on land and in the water; this animal crawls on a
muscular, boat-shaped foot (below left picture 4). Edible snail and sea snails have large and
long foots. Most of the internal organs are up in the shell, where they
Garden snails (Helix aspersa) and common land snails are small animals mostly found at the following places:
In fact they are almost everywhere. They are the most well known plant pests in all organic gardens.
We have learnt that garden snail has a shell and mostly in brown colour with darker patches (above image 6 at right). You can call those as brown garden snail. There are lines which run parallel with the margin of the shell. Their age are usually be determined by the interval between fine lines of growth. You can see there is sometimes in slight difference of colours; when you look closer.
By watching them everyday, you can see the snail can either extend a large portion of the body beyond the limits of the shell (above left picture 3); or withdraw entirely within it. All the tentacles can be withdrawn into the body by sinking the tip down into the part behind it, and gradually the whole structure disappears in minutes.
We have observed them quite a while, and found them having a flat and
very muscular foot; it is thickening extends along the entire length of
the animal, beginning below the month and reaching nearly as far behind
as in front of the shell; all snails and slugs creep along this organ.
There is a third family intermediate between the snails and slugs proper. It is 'Testacella'!
Testacella is a small shell-bearing snail slug and it is carnivorous (eating live creatures); which eats earthworms; or droppings of birds. They usually burying themselves deeply in the soil. You may find them upon the soil surface and upon walls after heavy rain. Because when the ground has become saturated with moisture, they will face difficulties in breathing; they carry a small but visible shell as a little cap on the hinder part of the body.
One of my girl friend from Denmark said that, the snail slug (above right picture 9) in their garden eats also their own family; the snail slugs are large and difficult to get rid; because there are plenty of them hiding themselves in a forest behind her house; European hedgehog will not eat snail slugs in their garden.
If you know what do snails eat and what plants do slugs eat; and the life cycle of a snail or slug; then you will know how to get rid of slugs and snails and keep them in control.
One said scattering pieces of orange peel over the ground, snails are so found of this delicacy that they will remain clinging to the peel rather than go back to their hiding places at break of day; you may examine the traps every morning and destroy them.
If you spend some time to observe them, you will discover more and more natural ways to avoid them without much troubles.
We discovered that snails have difficulties to climb small hills. If you have plants and vegetables growing on a small hill or a slope will reduce the chances of getting involved with the snails or slugs.
We found neither snails nor slugs are difficult to keep in captivity; they will
treat any vessel with a lid as a cage, so, you will see them often climb
to the top, when they are kept in a container. They stay most of time at a shady spot with a
fair degree of moisture; such as in the rain water barrel; and in the
compost bins. So, you know where you should look; if you wish to destroy them.
Someone said certain flower species are pollinated by snails and slugs; however, a further deep study is very necessary.
When all types of snails and slugs are in control; then you can concentrate fully on your organic gardening.