Fungal and arboreal biomass in a western Oregon Douglas-fir ecosystem: distribution patterns and turnover

The allocation of biomass and the turnover time of various components were measured from August 1976 to August 1977 in a young, second-growth Douglas-fir stand in the Oregon Coast Range. Allocation of biomass among the tree components was 14 732 kg foliage ha −1 , 30 455 kg branches ha −1 , 212 941 kg boles ha −1 , 49 289 kg nonmycorrhizal roots ha −1 , and 15 015 kg host portion of mycorrhizae ha −1 . Biomass allocation of fungal components was 10 009 kg mycorrhizal mantles ha −1 , 2785 kg Cenococcumgeophilum sclerotia ha −1 , 65 kg sporocarps ha −1 , 369 kg litter hyphae ha −1 , and 6666 kg soil hyphae ha −1 . The forest floor was composed of 6970 kg fine (<2 mm) litter ha −1 , 6564 kg coarse (2–25 mm) litter ha −1 , and 5500 kg log (>25 mm) litter ha −1 . Soil organic matter (<0.494 mm) was 87 600 kg ha −1 . Total annual stand throughput was 30 324 kg ha −1 , excluding soil organic matter throughput. Of this total, 50.5% was accounted for by fungal throughput, 39.5% by tree throughput, and 10.0% by forest floor throughput.