Urban stands are becoming increasingly important in improving the environmental health and liveability of cities. However, they weaken as a result of technogenic air pollution and become vulnerable to pests, particularly to non-native forest insects. The aim of this research was to assess potential harmfulness (bionomically determined harmfulness [BDH]), environmentally determined harmfulness (EDH) and generally expected harmfulness (GEH) of the gnawing phyllophagous lepidopterous insects in the green stands of Kharkiv (Ukraine). All supplementary parameters were assessed by analysis of publications and the own experience of authors. BDH was evaluated as a product of the duration of larvae nutrition (p1) and an index of larvae nutrition (p2). An index of larvae nutrition (p2) was considered being proportional to their imago wingspan. EDH was evaluated as a product of the value of damaged tree species (p3), location of plant damage (p4), the period of loss decorative effect (p5) and the prevalence of certain insect species in the stands (p6). GEH was estimated as a product of BDH, EDH and the ability of insect species to the outbreaks (p7). A modified approach for evaluation BDH, EDH and GEH was suggested and implemented, considering phyllophagous leaf miner insects and phyllophagous insects with open lifestyle in the deciduous stands of streets, parks, and Forest Park of Kharkiv city. EDH of insects with an open lifestyle depends on their size and prevalence in the stand. EDH and GEH of all revealed insects with an open lifestyle increase from streets to Forest Park. Among the insects with an open lifestyle, Lymantriidae and Notodontidae had the highest BDH due to the large size and long feeding period of larvae. Among the insects with hidden lifestyle, Cameraria ohridella had the highest BDH due to the highest prevalence and the large duration of feeding period with its several generations.

У вуличних, паркових і лісопаркових насадженнях листяних порід м. Харкова виявлено 108 видів гризучих комах-філофагів, які умовно розподілені на групи: комахи з відкритим способом життя (61 вид) із рядів Hymenoptera (2 види) та Lepidoptera (59 видів); комахи з відкритим способом життя з ряду Coleoptera (33 види); комахи з потаємним способом життя (мінери) (14 видів) із рядів Coleoptera (2 види) та Lepidoptera (12 видів). Видовий склад гризучих комах-філофагів у Лісопарку включає 105 видів, у парках 67 видів, а у вуличних насадженнях – 33 види. Розраховані значення індексу Менхініка (DMn) становлять 10,2; 8,2 та 5,7 у насадженнях Лісопарку, парків і вулиць. Найбільшу подібність комплексів комах-філофагів виявлено у парках і Лісопарку (Cj=0,52 для Coleoptera з відкритим способом життя; Cj =0,59 для Lepidoptera та Hymenoptera з відкритим способом життя і Cj =1 для мінерів). Більшість виявлених видів комах траплялися поодиноко або зрідка. Звичайним видом в усіх типах насаджень був Xanthogaleruca luteola, у Лісопарку – Chrysomela populi та два види роду Clytra, у парках – Tomostethus nigritus, у вуличних і паркових насадженнях – Cameraria ohridella.

The results of assessment of phyllophages’ trophic activity in the green stands of the City of Kharkiv with various anthropogenic influences are presented. The proportion of the leaf area removed by phyllophages with an open lifestyle was the highest in elm, ash, and oak, by miners — in oak and linden, by sucking species — in linden, and by gallers — in linden, elm, and oak. The average proportions of leaves with damage caused by phyllophages with an open lifestyle in houses’ yards do not differ from street ones, decrease from a forest park to parks and streets, in well-kept parks it is less than in unkempt ones, in streets in the city center — less than on the periphery, and in streets with heavy traffic — less than with weak one. The indicator of the average removal of leaves by phyllophages with an open lifestyle in the surveyed stands of the City of Kharkiv does not exceed 10%, that is, there is no threat to the sanitary condition of trees.