- 1University of Agriculture in Krakow, Faculty of Forestry, Department of Ecological Engineering and Forest Hydrology, Krakow, Poland
- 2Cleveland State University, Mechanical Engineering, OH, USA
- 3Cleveland State University, Biological, Geological and Environmental Sciences, OH, USA
- 4Jan Kochanowski University, Institute of Geography and Environmental Sciences, Kielce, Poland
- 5University of Agriculture in Krakow, Faculty of Forestry, Department of Forest Resources Management, Krakow, Poland
- 6University of Agriculture in Krakow, Faculty of Forestry, Department of Ecology and Silviculture, Krakow, Poland
- 7Mendel University, Department of Forest Botany, Dendrology and Geobiocoenology, Faculty of Forestry and Wood Technology, Brno, Czech Republic
Climate changes and biotic responses are increasingly undermining forest health worldwide. One such impact includes the intensification of infestations by semiparasitic plants like mistletoe (Viscum album L.). Mistletoe infestations can significantly disrupt the water balance of forest ecosystems, particularly in commercial forests. In 2023, mistletoe damaged 133.7 thousand hectares of forests in Poland, primarily affecting Scots pine (Pinus sylvestris L.). This study examined the water-holding capacity of tree canopies in mistletoe-infested and healthy stands of Scots pine and silver fir (Abies alba Mill.) in southeastern Poland, where air pollution is minimal, and mistletoe presence was rare before 2019. Using specialized imaging software (WinRhizo® Regular 2021 and WinSeedle® Pro 2022), we quantified the surface area of conifer shoots, needles, and mistletoe foliage, while laboratory simulations under controlled conditions measured water retention capacity.
Results indicate that healthy Scots pine canopies store 2.6 mm of water (20.3% of simulated rainfall), while silver fir retains 1.5 mm (14.8%). Mistletoe on pine and fir canopies stores substantially more water, 3.8 mm (24.9%) and 3.3 mm (29.5%), respectively. These findings suggest that mistletoe infestation increases canopy water retention capacity by up to 15%. The dynamic filling and emptying of this additional 1.5 mm of water storage capacity by mistletoe-infested canopies could result in an additional 5-10 % reduction in water reaching the forest floor, emphasizing the ecological significance of mistletoe in altering interception and infiltration processes.
These findings highlight the need to integrate mistletoe infestation into forest water balance models, especially as drought conditions intensify. A deeper understanding of Viscum album’s role in exacerbating drought stress will enhance predictions of forest resilience and support the development of forest management strategies that safeguard water resources and the economic sustainability of affected stands
How to cite: Klamerus-Iwan, A., Van Stan, J., Kozłowski, R., Netzel, P., Banach, J., Stopyra, M., Słowik-Opoka, E., and Urban, J.: Mistletoe Infestation in Conifer Stands: Implications for Forest Water Balance, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-18171, https://doi.org/10.5194/egusphere-egu25-18171, 2025.
