This is a dry branch covered with lichen and moss. It is not a single organism in itself, but a natural object composed of multiple elements and organisms. Lichens and mosses themselves do not harm healthy trees, they just use the bark as a stable attachment point to collect sunlight and rain. Their presence usually indicates that the branch has died or aged, as they prefer to grow on sunny, slow-growing surfaces.

Rotten wood moss is slender or thick, yellow green or dark green, slightly brownish green in color, and glossy. The stem crawls and branches densely. The leaves are curved, almost sickle shaped, with a long oval base, concave inward, and long pointed; The leaf edge is slightly curled, with fine teeth on the upper part; Middle ribs are often missing. The leaf cells are diamond shaped or elongated diamond shaped, with a yellow base, and the horn cells are relatively swollen and golden yellow. There are a few short cells above them, which are often transparent. Dioecious plants, rare dioecious plants with the same bract, or leaf bearing male bract plants with different bracts. The inner female bracts have longitudinal folds, long haired tips, and fine teeth on the upper edges.

Dead trees in the forests of the Pacific Northwest region in autumn

Warm ground moss is an important medicinal moss plant with good therapeutic effects on cardiovascular diseases. Plants of the genus Bryum in the family Bryaceae. Short and large in size, bright green, slightly glossy, scattered in patches. The stem is full of vigor, creeping and extending. The lower leaves of the upright stem are small and scale like, covered with tiles and sticking to the stem. The top leaves are clustered in a large flower bud shape, long in an inverted or long tongue shape, sharp and pointed; Leaf edge differentiation, upper part toothed, lower part slightly rolled back; The middle rib is single and extends up to the tip of the leaf; The leaf cells are thin-walled, hexagonal, and the base cells are rectangular. Dioecious plant. Capsule stalk grows at the top of a straight stem, clustered in single or multiple clusters. The sporangia are cylindrical, arranged horizontally or heavily inclined.