Artificial barriers against arionid slug movement

Arionid slugs can be serious pests on horticultural and agricultural crops. Using slug movement barriers is a potentially effective method to control slug damage. We evaluated the performance of waterglass (sodium silicate) and copper foil as barriers against Arion vulgaris movement both in a controlled experiment and in a semi-field validation under natural conditions. We used strawberry fruits as baits behind the barriers and monitored slug movement and damage to the strawberries. In the controlled experiment, copper foil barriers delayed but did not prevent passage, whereas waterglass barriers completely hindered slugs from passing. Barrier width (3, 4 or 6 cm) did not affect the passability of the barriers. In the semi-field validation, there was no difference in slug damage events between pots with and without copper foil barriers. Waterglass barriers applied to the pots reduced slug damage events by 50% compared with pots without a barrier. Using waterglass to hinder slug movement may prove to be a cost-effective method to control slug damage in horticulture without any adverse side effects on non-targeted organisms.