Cones of Douglas-fir and ponderosa pine with extensive mold on external portions of scales were sampled for presence of fungi potentially pathogenic to conifer seedlings in nurseries. The major colonizers of cone scales and external seedcoats for both conifer species were Trichoderma spp. Penicillium spp. were also very common. The only potentially pathogenic organisms found on moldy cones were low levels of Fusarium (F. acuminatum and F. oxysporum), Cylindrocarpon (C. tenue, C. didymum, and C. gracile), and Bottytis cinerea. Levels of these potential pathogens were only a fraction of that of the common saprophytes, Trichoderma and Penicillium. Tests to evaluate effects of these fungi on seed germination and seedling establishment are needed. Cones with high levels of external moldiness were not extensively colonized with potentially pathogenic fungi and need not be discarded because of extensive fungal growth.
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