Slugs And Snails

Mitigating the menace of maraudingmolluscs.

- Paul Donovan

Slugs and snails are the bane of the gardener, and also wreak havoc on a host of agricultural and horticultural crops. These common pests are classed as gastropods in the mollusca (mollusc) phylum that also includes squid, cuttlefish and octopuses, as well as others. The only difference between a slug and a snail is that the snail has a spiral shell into which it retreats.

Other than the presence of chewed plants, one of the tell-tail signs that slugs and snails have been marauding in your garden is the silvery mucus trail they leave behind. The mucus is secreted by the muscular foot, to aid its movement.

Slugs and snails are hermaphrodites; that is they have both male and female sex organs, so anyone individual you may find has the potential to lay eggs. The eggs are laid in clusters in the soil, beneath leaves or in other areas where the soil is damp. They may be opaque, white or yellowish-brown in colour. Depending on the species, several clusters may be laid during the year. The eggs take 1 – 2 weeks to hatch, depending on the species, but may lay dormant in the soil for months and hatch only when conditions are suitable.

Damage

These marauding molluscs are nocturnal by nature, emerging under the cover of darkness to feast on decaying matter, living plants, flowers, ground fruits such as strawberries and tomatoes, citrus fruits and even the young bark of trees. Evidence of slug or snail damage is large, ragged holes chewed in leaves, leaves with scalloped edges, or seedlings that have been completely stripped of their leaves and reduced to a bare stem.

Control Slug and snail control can be broken down into several approaches:

Mechanical