Authors: Martikainen, Petri & Penttilä, Reijo & Kotiranta, Heikki & Miettinen, Otto
Journal: Karstenia, Volume 40 (2000), Issue 1-2, pages 79-92.
Full text: PDF
Key words: aspen, conservation implications, Funalia trogii, habitat ecology, Perenniporia tenuis, Polyporus pseudobetulinus, threatened polypores
Abstract: We report the results of three extensive surveys between 1996 and 1999 on the polypore flora of dead aspen trees (Populus tremula L.) in eastern Finland. These surveys yielded several new finds and new information on the habitat requirements of three polypore species classified as endangered in Finland: Funalia trogii (Berk.) Bondartsev & Singer, Perenniporia tenuis (Schwein.) Ryvarden and Polyporus pseudobetulinus (Pilát) Thorn, Kotir. & Niemelä. Our observations confirm that F. trogii is a thermophile preferring sun-exposed habitats. Similarly, all new records of P. tenuis were made in open habitats. P. pseudobetulinus has also been found occasionally on retained aspens in clear-cut areas, although it is usually located in old-growth forests. Our results suggest that these and other threatened species with similar habitat requirements could possibly survive even in a managed forest landscape, provided that potential host trees are retained in sufficient numbers. Most of the new records derive from trees killed by notching or girdling, indicating that suitable host trees for these species can be created even by killing trees. However, notching or girdling should be used with caution because it will reduce the availability of aspen trees in the future.