The Silver-Y Moth [ Autographa gamma]] is a migrant moth and normally migrates from Africa and the mediterrean region to the United Kingdom from June onwards. The moths can be active in the day and the night. The moths are brown to grey with an irregular white mark.They fly from plant to plant or flower to flower and are often observed sitting on leaves with their wings folded back. The moths feed on nectar and the females lay eggs either as individual eggs or in groups. The eggs are grey-white in colour, round and flat. One female can lay up to 2,000 eggs. After about 10-14 days caterpillars hatch from the eggs. The caterpillars are green with a light coloured stripe and they have a looping way of moving. The caterpillars are nocturnal. Once fully grown the caterpillar will eventually pupate as a green to black pupa, often covered in silk threads wrapped in leaves.
Plant damage is caused by the caterpillar stage of the life cycle. They will attack greenhouse grown plants and outdoor crops like Peas and Beans. Growing points on plants are often damaged , sometimes leaves are skeletonized after caterpillar feeding and damage to Pea and bean pods can be severe. They will also leave frass on plants.
How to control Silver Y moth
Pheromone traps with Silver Y pheromone lures can be used to monitor and check for the moths arrival from late May onwards. Caterpillar Killer nematodes can be applied to control the caterpillar stage.