Mycofloral succession onPinus densiflora needles on a moder site

Mycofloral succession on decaying pine needles in aPinus densiflora forest on a moder site was investigated in Sugadaira, Nagano Pref., central Japan. Dead needles on the tree, fallen needles obtained from two recognizable sublayers of the L layer and the upper sub-layer of the F₁ layer in the organic horizon were examined for their fungal flora using both washing and surface sterilization techniques. The major interior colonizer in freshly fallen needles varied with the season:Chaetopsina fulva in summer andSelenosporella curvispora in the other seasons.Thysanophora penicillioides was a remarkable external colonizer of freshly fallen needles in summer, while soil fungi were external colonizers of such needles in the other seasons. A possible successional change of major fungi with the needle decay was suggested. The observed seasonal alternation of the species colonizing freshly fallen needles was discussed in relation to climatic conditions. Contributions from Sugadaira Montane Research Center, No. 152.