INSETTI DANNOSI AL FRASSINO NELL'ITALIA CENTRALE.

Insects causing damage to ash in central Italy - Observations have been carried out over a number of years on the presence and damage caused by insects linked to ash in young pure stands planted in the provinces of Florence and Rome and in stands of adult trees in the Maremma. Among the Homopterans, whiteflies and psyllids were found in all environments, with infestations sometimes leading to summer leaf drop; aphids belonging to the gen. Prociphilus Koch were also present in a young stand, but were never responsible for intense attacks. Severe problems were caused by another Homopteran, the flatid planthopper Metcalfa pruinosa (Say). In recently established plantations considerable damage was also caused by the oviposition wounds of Auchenorrhyncha Homopterans, mainly inflicted by the leafhopper Cicadella viridis (L.) However the most numerous group of insects, causing the most severe damage to ash, consists of defoliators: in ash stands situated in the warmest areas we observed pronounced defoliations caused by adults of the blister beetle Lytta vesicatoria L. and by larvae and adults of the weevil Stereonychus fraxini De Geer. Among Lepidopterans, during the first years of the observation period the geometrid moth Calospilos pantarius (L.) launched intense attacks on specimens of ash growing in the coastal area of southern Tuscany. Sporadic attacks, which were sometimes intense on individual trees, were made by the larvae of Gracillariidae, Tortricidae, Noctuidae, Lymantriidae Lepidopterans and by various other species of Geometriidae such as the polyphagous Operophthera brumata (L.). Gall midges of the gen. Dasineura Rondani were found on ash in the Maremma: of the three species identified, severe infestations were caused above all by D. fraxinea (Kieffer). Throughout all the environments considered, the presence of mines due to the leaf miner fly Aulagromyza fraxini Beiger was detected on leaves.