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.