Wood-inhabiting fungi on pedunculate oak coarse woody debris in relation to substratum quantity and forest age

Abstract

Wood-inhabiting fungi on pedunculate oak (Quercus robur) coarse woody debris (CWD) was investigated in 50 plots of 0.1 ha in oak stands of different ages in Lithuania. In maturing stands (50-120 years) the average volume of oak CWD was 4.7 m³/ha, and in mature stands (over 120 years) – 13.9 m3/ha. Both in maturing and mature stands, the greatest fraction of CWD consisted of fallen oak branches (81 % and 84 % respectively), whereas fallen trunks comprised about 10 % of the total units of CWD. In total 1350 records of 203 species (49 ascomycetes and 154 basidiomycetes) were collected during 2 years of investigation. Species richness and abundance increased significantly with the increase of volume and abundance of CWD. Higher species richness was detected in mature stands than in maturing ones. Wood-inhabiting species composition varied greatly at stand scale, and one third of all detected species occurred only in one plot. Red-listed fungi were found only in mature stands. We conclude that, even in managed oak stands, oak CWD maintains a rather diverse species composition of ascomycetes and basidiomycetes. However, the current practice of forestry in Lithuania of removing dying or dead wood of large volume, e.g. standing and fallen trunks, reduce the distribution of highly specialized, usually rare, and endangered fungi.