Slugs

Slugs have an elongated, soft, shell-less body with a pair of upper tentacles bearing eyes, and move on a mucus-lubricated muscular foot. The silvery slime trail left behind as they move and feed is one of the most reliable diagnostic signs of their presence.

• Irregular, ragged holes in leaves, often with smooth edges
• Silvery slime trails on soil, foliage, or fruit surfaces
• Damage to seedlings that can appear suddenly overnight
• Slugs themselves found sheltering under debris or in soil cracks by day

Slugs are hermaphroditic, with each individual having both male and female reproductive organs, though many species still mate. Eggs are laid in clusters in moist soil or under debris, and juveniles resemble small adults, growing through repeated feeding.

Slugs are most active at night or during humid, overcast weather, sheltering in soil cracks, under debris, or in dense vegetation during dry or hot periods. Populations can persist across multiple seasons in consistently moist, favourable habitats.

Feeding produces irregular, ragged holes in leaves and can destroy seedlings outright, while fruit that touches or hangs near the ground can be scarred or tunnelled into. Slime trails and feeding damage can also affect the marketability of leafy salad crops even when the plant otherwise survives.

Hosts include lettuce, cabbage, and strawberry among many other low-growing vegetable and fruit crops.

Field scouting after dusk or during damp weather, when slugs are most active, helps confirm presence and estimate pressure. Baited traps, such as damp boards or shelters checked periodically, are commonly used to estimate populations, particularly before planting susceptible seedling crops.

Slug management focuses on reducing the moist, sheltered conditions slugs favour and protecting the most vulnerable seedling stage.

• Improve field drainage and reduce excessive surface moisture or residue where practical
• Conserve ground beetles and other natural predators
• Monitor with baited traps or shelters ahead of planting to judge risk
• Time tillage and residue management to reduce sheltering sites
• Choose less-palatable crops or timing in fields with a history of high slug pressure