The horse chestnut leafminer Cameraria ohridella: chemical control and notes on parasitisation

The efficacy of four different insecticides against Cameraria ohridella, Dimilin, Confidor, Calypso, and Dimilin, was investigated in experiments with potted horse chestnut seedlings and on full-grown trees. The parasitoids found in mines with larvae and pupae of C. ohridella on A. x carnea and A. hippocastanum were also recorded and determined. The expected high efficacy of Dimilin but also good protection by treatment with Confidor and Calypso were demonstrated. Mospilan was less effective. A high mortality of ultimate larval instars of the leafminer and their substantial parasitisation was observed in experiments with potted seedlings when Confidor and Calypso were used. The most abundant parasitoid species was Minotetrastichus frontalis.