The dissertation is devoted to the actual pests of spruce under the conditions of Kharkiv city – spruce bud scales. The species composition of phytophages was clarified, and three species of scales have been identified: Physokermes piceae Schrank, 1801; Physokermes hemicryphus Dalman, 1826, Physkermes inopinatus Danzig & Kozаr, 1973 (Hemiptera: Coccidae: Physokermes), the last species was first recorded in the region. The study of biotopic distribution showed that in Kharkiv city, small spruce bud scales prevails and in Kharkiv region, big spruce bud scales prevails.
Detailed studies of the biology and ecology of spruce bud scales were conducted for the first time in the north-eastern part of Ukraine, the main attention was paid to the phenology, forage plants, biology of development, and the influence of abiotic and biotic factors on phytophages.
All three species give one generation during the year, reactivation of winter diapause occurs with a stable temperature transition through + 5 °C. The differences in the phenology of big and small spruce bud scales have been clarified, and it is advisable to use the obtained information when planning protective measures. It has been established that forage plants in the region of research are the following species ‒ European spruce, prickly spruce, Canadian spruce and their decorative forms. It has been proved that the fecundity of spruce bud scales is determined by the conditions of nutrition and the state of air cleanness, on the territories with polluted atmospheric air – along roads, the fecundity significantly decreases.
In regulating the number of spruce bud scales, the most important predator is Anthribus nebulosus Foerster, 1770 (Coleoptera:Antribidae) and parasitoids – incheumonids Microterys lunatus Dalman, 1820 (Hymenoptera:Encyrtidae), their biology and phenology have been clarified. Colonization by entomophages varies significantly and reaches the highest rate in park plantations remote from highways (60-75 %), the lowest in plantations located along highways (10-15 %).
It has been established that the nutrition of spruce bud scales leads to yellowing and falling of needles, a decrease in annual growth, which leads to a weakening of spruce trees and even their death.
It has been proved that the most harmful are larvae of the second age and young immature females. According to our research, it is advisable to carry out chemical protection in nursery gardens at the stage of a young immature female, in the region of research this is the first decade of May.
Systemic (Actara 25 WG water-soluble granules, Movento 100 SK suspension concentrate), complex preparations (Engio 247 SC suspension concentrate, Proteus 110, OD MD) and growth stimulator Megafol were used for chemical protection. All insecticides showed high technical efficiency – from 91% to 98%. Chemical protection for three years made it possible to reduce the level of colonization to single individuals or completely free the spruce from spruce bud scales.
