Turnip Moth

• It does not devour the whole plant: it cuts it off at the base, so that a single caterpillar can ruin dozens of seedlings in a night while eating almost nothing.
• The damage shows up as gaps in the crop rows, and the culprit is found curled up in the soil a few centimetres from the severed plant.
• The caterpillar curls into a perfect C when uncovered, a defensive posture typical of soil-dwelling noctuids.
• The caterpillar is known as a cutworm, and its damage is characteristic: it mows down seedlings at ground level during the night, cutting through the stem, and in the morning the grower finds the plant lying flat and apparently intact.
• By day it stays buried beside the plant it has cut, curled into a C shape, which makes it hard to find.
• It attacks practically any herbaceous crop: beet, maize, potato, vegetables and cereals.
• It is migratory: the adults travel long distances, and northern European populations are renewed each year by arrivals from the south.
• Control relies on pheromone traps to track the flights and decide when to treat, because the caterpillar is only vulnerable in its early stages.

Skeleton type

Invertebrate - chitin exoskeleton (insect)

Habitat and environment

Arable crops, vegetable plots and disturbed soil

Size at birth

The larva reaches 40-50 mm when fully grown

Litter / clutch size

Several hundred eggs per female, spherical and strongly ribbed, laid in the soil or at the base of the host plants

Sources consulted: CABI Compendium · EPPO · Ministerio de Agricultura de España · Hebrew University of Jerusalem, ficha de plagas mediterraneas · Gianluca Doremi, ficha Agrotis segetum · Hantsmoths · iNaturalist, ficha Agrotis segetum · UKmoths, ficha Agrotis segetum · Gianluca Doremi

Best time: Double generation: the adults fly in May-June and again in August-September; the flights can start in April and go on until November