Paper presents a systematic global review of Acer negundo, Fraxinus pennsylvanica, Ailanthus altissima, Robinia pseudoacacia invasions focusing on the Scopus and Web of Science databases. We examined the data on papers, study areas, habitat studied, topic discussed. We hypothesized that these species were studied evenly throughout their invaded ranges and, as such, indexed by international databases. We asked whether four selected species are presented evenly in publications related to their invaded ranges, and whether both selected databases cover well a content of these papers. We found 48 papers for A. negundo, 14 – for F. pennsylvanica, 83 – for A. altissima, 96 – for R. pseudoacacia. A high percentage of the studies were conducted in Central Europe and USA (for A. altissima), while Eastern Europe, Russia, Western United States were poorly represented. Most studies were conducted in forests, and focused on impacts or distribution of aliens in invaded range, and their control and management. We encountered habitat types invaded by trees, factors influencing tree invasions, consequences of invaders’ impact on ecosystems, counteracting measures. We concluded that the use only Web of Science and Scopus is not sufficient to obtain the complete data about the invasion biology.
