White garden snail

Theba pisana, commonly known as the white garden snail, is a member of the Helicidae family. It is recognized as a significant agricultural pest worldwide, particularly in regions with a Mediterranean climate. Due to its high reproductive rate and tolerance to dry conditions, it can establish large populations in a very short time.

This pest is highly polyphagous and infests a diverse range of crops, including cereals, pulses, citrus orchards, vineyards, and various vegetable gardens. Beyond consuming leaves and stems, their presence creates logistical challenges; large clusters of snails can clog harvesting machinery, significantly complicating agricultural operations.

The biology of the species is marked by a strategy called aestivation. During dry and hot seasons, the snails adhere to plant stalks or fences to avoid desiccation, entering a dormant state. They resume feeding and reproductive activities when moisture levels rise, typically after the first autumn rains, leading to rapid expansion of the population.

The damage caused by the white garden snail includes defoliation, destruction of seedlings, and contamination of harvestable produce with mucus and excreta. This not only causes direct yield loss but also affects the market quality of the crop, making it undesirable for consumers or processing facilities.

Integrated Pest Management (IPM) is essential for controlling this pest. Recommended practices include deep tillage to destroy egg-laying sites, maintaining clean fields free of excess debris and weeds, and using physical barriers. Chemical control involves the application of molluscicides, primarily based on metaldehyde or iron phosphate, applied during periods of active feeding.