Food Plant: Luzula sylvatica (Greater wood-rush)

Egg; laid on a flower

Mine: July-October (then some continue May-August; others do not feed in their second year)

Notes: Have a complex bienniel life cycle with larvae feeding within the seedhead. In a later instar they make a case from a floret, which surrounds an ochreous case, with a distinct neck. Diapause is spent amongst fallen leaves on the ground. They may pupate in this leaf litter or crawl up tree trunks (to a height of 1.25m). The final case is 5-7mm long and is bicoloured, consisting of a darker flower bract covering two thirds with the light silken case the final third. Larval cases fixed for pupation on a tree trunk growing among Luzula sylvatica. This can be a good way to find larvae in the spring, 28 cases were found in half an hour of searching here, with cases on most tree trunks among a large, continuous patch of Luzula sylvatica.

Data: 01.iv.2023, Bagley Woods, Oxfordshire, VC23

Image:© Will Langdon