Worms, Slugs & Snails

What are worms?

An Earthworm

Worms have evolved over millions of years into fast and efficient natural composters. Each worm eats and digests up to half its own body weight in waste every day, greatly reducing its volume. As a result the worms produce high quality compost.

Organic matter eaten by earthworms consists of rotting plant material and animal parts. They also eat soil harmful micro-organisms such as bacteria, fungi, and nematodes. earthworms will feed on roots or other parts of plants that have been decayed by other organisms.

Earthworms are generally found in the top 10 or so few centimetres of the soil. They breath through their skin and therefore need a moist environment, so if the soil dries excessively, they will burrow deeper. They are basically nocturnal up to 2 m (6 ft), coming to the surface at night when temperatures are lower and humidity higher. Sandy and acidic soils are their least favourite habitats.

What are slugs?

A slug

Slugs are hermaphrodites: they all have male and female reproductive systems. They can stretch to 20 times their normal length enabling them to squeeze through openings to get at food. Slugs can also follow slime trails they left from the night before. Other slugs can also pick up on this same trail.

Slugs and snails actually both have shells. Slugs' shells are much smaller and not visible as they are underneath the flesh on their back.

Slug eggs are in the soil just about everywhere. They can be there for years and then hatch when conditions are right. It actually takes moisture to allow them to hatch. Eggs are laid in clusters of two dozen eggs each. Many slug species do not hibernate like many land snail species, and they die in autumn leaving the eggs behind.

What are snails?

A snail

A snail consists of two main parts. A foot, that is mostly muscle, which it can draw into its shell, and the digestive glands and lung, which remain permanently inside the shell.

A snail retreats into its shell when danger threatens, or when the climate gets too cold or dry. In the winter, they find a sheltered place and glue themselves onto a fence or wall, or flowerpot, and wait for the cold weather to pass. They do the same if there is a heat wave. The shell grows larger as the body grows.