Ubiquity of methanogenic archaea in the trunk of coniferous and broadleaved tree species in a mountain forest.

Wetwood of living trees is a habitat of methanogenic archaea, but the ubiquity of methanogenic archaea in the trunk of various trees has not been revealed. The present study analysed methanogenic archaeal communities inside coniferous and broadleaved trees in a cold temperate mountain forest by culture-dependent or independent techniques. Heartwood and sapwood segments were obtained from the trunk of seven tree species, Cryptomeria japonica, Quercus crispula, Fraxinus mandshurica, Acer pictum, Aesculus turbinata, Magnolia obovata, and Populus tremula.