The scale insects (Homoptera: Coccoidea) of deciduous fruit orchards in some European countries. (Survey of scale insect (Homoptera: Coccoidea) infestations in European orchards No. III.).
During surveys in orchards in Czechoslovakia, Greece, Hungary, Poland, Turkey, the European part of the USSR and Norway, 25 species of scale insects were found in branch and bark samples of fruit trees. The most frequently occurring species, in order of decreasing importance, were Quadraspidiotus perniciosus (Comst.), Lepidosaphes ulmi (L.), Epidiaspis leperii (Sign.), Q. ostreaeformis (Curt.) and Parthenolecanium corni (Bch.). The same species were present in a significant proportion of the areas studied. The species detected in relatively more restricted areas, but in very high abundance, were Parlatoria oleae (Colv.), Pseudaulacaspis pentagona (Targ.), Lopholeucaspis japonica (Ckll.), Q. marani Zahradnik, Q. pyri (Licht.) and Sphaerolecanium prunastri (Boy.). Outbreaks of Partholecanium corni and S. prunastri in 1976 were recorded, the former occurring over large areas and the latter in smaller, isolated localities. Considerable alterations were also established regarding the species composition of scale insects in orchards in various geographical regions.