In 2010-2011, a study of the occurrence of aphids was carried out in three parks in Bydgoszcz, the Balaton Park, the Jan Kochanowski Park and the Park by Unii Lubelskiej. Observations were made every ten days by monitoring trees and shrubs as soon as aphids appeared, i.e. from the end of April to the beginning of August. The counts of aphids were replicated three times, on each plant species where the insects were observed. Based on the collected material, 14 aphid species were found on 16 plant species in the Jan Kochanowski Park, 16 species of aphids on 14 plant species in the Balaton Park and in the Park by Unii Lubelskiej, only 12 species feeding on 16 plant species. In both years of the study, of aphid species feeding on trees and shrubs, Aphis fabae, Aphis sambuci, Aphis spiraephaga and Hyalopterus pruni, occurred most frequently. The Balaton Park was characterized by the largest number of aphids colonizing plants; in contrast, the number of tree and bush species on which they fed was the lowest

Cypripedium calceolus is considered an endangered species in the territory of Poland. Population of this rare species, situated at Lake Kwiecko (Western Pomerania), was regularly monitored in the years 1986-2013. The studied population has been under the permanent influence of the nearby hydroelectric power plant for almost 45 years. The field observations showed that the power plant had no negative impact on the condition of Cypripedium calceolus population. An indication of its good condition was, among others, an increase in the size -from 150 to 350 specimens within the study period.

Some aphid species are important agricultural pests, sometimes also found on plants growing in urban areas. In this work, we set out to identify the plant species, communities or habitats that are more attractive to aphids in order to limit their spread into new green areas. The aim of the study was to determine and compare plant communities and the assemblages of aphids associated with them in different urban park habitats. The research hypothesis assumed that the differences between aphid assemblages depend on plant diversity and hence reflect urban park habitat environmental conditions, in particular the plant communities and the floral structure. The study was carried out in Bydgoszcz (northern Poland), and four parks were taken into consideration. Herein, floristic lists were used to calculate ecological indicator values for each park. The aphid species richness was determined, as well as the relative abundance and dominance structure similarities of the aphid assemblages. Our results demonstrated that Prunusspp. were strongly infested by Hyalopterus pruni, similarly as Philadelphus inodorus by Aphis fabae, Sambucus nigra by Aphis sambuci, and Acerplatanoides and A. pseudoplatanus by Periphyllus testudinaceus. Park plantations of Robinia pseudoacacia were not very attractive to aphids. The most attractive plant communities to aphids were syntaxonomically identifiable as alluvial alder forests in the layer of trees and Cornus sanguinea in the layer of shrubs.