During the ALIEN CSI BioBlitz 2022, which took place in Croatia on May 20 and 21, 2022, in the eight counties that participated in the project, a total of 196 findings of invasive alien plant species were reported. Twelve invasive alien plant species and one alien insect pest (oak lace bug) finding have been reported. The most recorded findings were for the following species: Japanese knotweed (61), daisy fleabane (34), tree of heaven (21), milkweeds (21), Virginia creeper (19) and boxelder maple (10). Furthermore, the findings of black locust (9), Japanese creeper (6), ragweed (5), Indian strawberrie (5), desert false indigo (3) and goldenrod (1) were also reported. Most findings were reported in the Zagreb County (70 observations), followed by Krapina-Zagorje County (58 observations), the City of Zagreb (30 observations), Sisak-Moslavina County (24 observations), Virovitica-Podravina County (10 observations), Karlovac County (1 observation), Brod-Posavina County (1 observation) and Bjelovar-Bilogora County (1 observation). Observations of invasive alien plants have also been reported in three protected areas - in the Maksimir Nature Park (city of Zagreb), Samoborsko gorje - Žumberak Nature Park and Lonjsko Polje Nature Park. During the ALIEN CSI Bioblitz Croatian app Invazivne vrste u Hrvatskoj (https://invazivnevrste.haop.hr/novosti/25) was used for recording the species.
Authors: Bozena Mitic and Dinka Matosevic