Abstract: The Larix gmelinii, Sphagnum bog in Xiaoxinganling is a typical oligotrophic bog in China, in which that the forest doesn't grow well, theSphagnum and the evergreen bush grow well is connected with the hydro-logic condition of the bog and the content of nutrient, trace elements ofthe peat. The content of main trace elements such as B, Cu, Co, Mn, Znetc. in different plants is different, The content of main trace elementsof different organs in one plant is also different, that changes along withthe season. The content of main trace elements of Ledum palustre. var.angustum and the changed law of the content in different season are same with that of Chamaedaphne calyculata. The two kinds of Sphagnum are same, which are obviously different from that of Larix gmelinii.

Key words: Bog plant, Trace element, Seasonal change