Common woodlouse

The common woodlouse (Oniscus asellus) is a terrestrial crustacean belonging to the order Isopoda and the family Oniscidae. Despite their crustacean lineage, they have successfully adapted to life in moist terrestrial environments, frequently infiltrating gardens and glasshouses.

This pest affects a variety of crops, primarily targeting seedlings, young shoots, and fruits that are in contact with the soil. Greenhouse environments are particularly vulnerable, as the high humidity and organic debris provide optimal conditions for the survival and proliferation of Oniscus asellus.

The biology of the common woodlouse is strictly linked to moisture. Since they respire through gills, they require damp habitats to avoid desiccation. They are nocturnal creatures, spending daylight hours in dark, secluded places, which makes early detection of an infestation challenging for the average grower.

Damage occurs when woodlice consume plant tissues, often leaving characteristic ragged holes in leaves and stems. Their feeding activity is most harmful to young, tender plants, as it can cause stunted growth or complete destruction of the seedling root or stem, leading to economic losses.

Integrated pest management strategies include:

• Improving greenhouse ventilation to reduce overall humidity levels.
• Clearing away piles of debris, boards, or decaying organic matter that serve as shelters.
• Using barrier methods such as mulching or raised beds to reduce contact between plants and soil.
• Applying targeted baits or biological controls when population densities reach threshold levels.