Slug damage in potatoes in The Netherlands

Abstract: At times, slugs are reported causing severe damage in potato tubers on loess soils.Tubers show relatively small holes and larger cavities inside. Slime and occasionally slugs areobserved. Damaged tubers are not saleable and severe affected lots of potatoes are rejected fromthe market. The moment when farmers observe damage is rather late and control actions arelimited. In contrast to the British situation, studies on slug species responsible for potato damagein The Netherlands have been underexposed. Neither control strategies nor factors influencingslug population densities have been investigated regarding the specific species. In 2009 apreliminary study was started aiming at finding the slug species responsible and make aninventory of factors with a possible relation to slug population dynamics. Farmers facingproblems with slugs have been visited and were exposed to an extensive questionnaire. Fieldswhere damaged potatoes were harvested were compared to fields lacking any slug damage.Subsequently farmers suffering no slug damage in potatoes at all have been exposed to the samequestionnaire. Both target growers were questioned on experiences with slugs, control methodsand crop production management. The results with ‘soft’ conclusions are discussed.