Spatial distribution of <Emphasis Type="Italic">Collybia pinastris</Emphasis> sporophores in a <Emphasis Type="Italic">Picea abies</Emphasis> forest floor over a 5-year period

Collybia pinastris is a relatively common litter-decomposing basidiomycete in spruce forests in Hokkaido, Japan. The spatial distribution of sporophores of C. pinastris was investigated for 5 years within a plot of 3m × 10m in size (subdivided into 0.5m × 0.5m subplots) in a pure stand of Picea abies. There were significant differences in the total numbers of sporophores during the sampling years. The total number of subplots in which sporophores occurred were also significantly different during the sampling years. However, the spatial distribution of the subplots with sporophores showed agreement with the distributions in subsequent years. There was no significant correlation between the number of sporophores and the thickness of the litter layer in the subplots, whereas the litter layers in the subplots with sporophores were significantly thinner than those without sporophores. These results suggested that perennial or renewable mycelia of C. pinastris occupied the same or close locations year to year for at least 5 years and that the spatial distribution in this plot was restricted not by a shortage of substrates but by other factors.