The invasive Himalayan balsam : Current status in Umeå, Northern Sweden

Abstract: Impatiens glandulifera is an invasive species throughout Europe. It was introduced to the wild in 1918 by escape from private gardens as well as the transport of garden soil and waste. Impatiens glandulifera prefers moist soils with moderate shade and commonly grows in riparian environments. In the Umeå municipality in northern Sweden, where this study is focused, the number of Himalayan balsam observations has dramatically increased over the last few years. This study aimed to determine habitat and anthropogenic land-use factors that may have contributed to the spread of Himalayan balsam in the Umeå municipality. This was done by using data on recorded observations of the species in a database called Artportalen. In order to determine how abundant and in which habitats Himalayan balsam occurs in the Umeå municipality, data on recorded observations in Artportalen from the Umeå municipality region for the period 01-01-2021 to 31-12-2021 was used along with maps from Google Earth Pro and Google maps. It was found that Himalayan balsam is now common in the region and does not show a definitive preference for riparian habitats or for forest or open areas in the Umeå municipality. Human activities seemed to be the main contributor to the spread of Himalayan balsam in the Umeå municipality.