The growing intensity of climate change combined with increased urbanization is causing a modification of weather patterns in Central Europe, specifically the rising temperature and precipitation distribution and intensity in recent decades. These phenomena adversely affect groundwater levels, indirectly affect forest ecosystems, and contribute to declining in tree health. For example, this affects their susceptibility to external pathogens (i.e. insects, fungi, parasites, etc.) that can lead to tree mortality. One of the pathogen examples is common mistletoe (Viscum album L.), a semi-parasitic plant of the sandalwood family that can photosynthesize. Until recently, mistletoe in Central Europe was mainly observed on deciduous species, but in the last few decades, it has begun to spread to coniferous species. The phenomenon was first recorded in the south of Poland, but it has spread to the north in recent decades. The mistletoe activities started during the last 40 years based on the size of the mistletoe on the trees and its estimated age. Mistletoe has recently appeared on a larger scale in forest stands where it was not a significant threat in the past. The most dangerous subspecies of common mistletoe is Viscum album ssp. austriacum, which primarily attacks Scots pine (Pinus sylvestris L.), the main forest-forming species of Central Europe.