Horse-chestnut leaf miner
develop. Trees with a low number of attacked leaves are not greatly affected, but when the entire surface of leaves is covered with mines, the leaves start [...] The pupa is brown and is 2.9-4.5 mm long. The horse-chestnut leaf miner overwinters in the pupal stage in a cocoon in dead leaves. The emergence of adults [...] spread to most of Europe. Since then, in all invaded regions, outbreaks have continued unabated, causing aesthetic damage to horse-chestnut, one of the favourite