Subject and Keywords:
The aim of the study was to determine the species composition of microscopic fungi colonizing dead wood of birch, beech, sycamore maple and sorb (Karkonosze Mountains), and black alder, mountain pine, willow, Swiss pine, sorb, sycamore maple and birch in the Tatras. The mycological analysis was conducted in 2015 and 2016 in the foothills and in the lower and upper montane zones of the Karkonosze Mounts, Karkonosze National Park, and in 2016 in the Białka Valley and Chochołowska Valley in the Tatras, Tatra National Park. For both, Karkonosze Mounts and Tatras, the dominant microscopic fungi inhabiting dead wood belonged to the genus Trichoderma. The Mycobiota of dead wood in the lower classes of decomposition was characterized by a higher species biodiversity but the lower numbers of colonies isolated.