Common Smoothcap

Common smoothcap, Atrichum undulatum, is a moss of the family Polytrichaceae with dark green, narrow, pointed leaves up to a centimeter long on stems reaching several centimeters, their margins lined with paired teeth and distinctly wavy, or undulate, when moist while crisping up when dry. It forms extensive patches in shaded woodland, on banks, heaths and in humic, moist soil across Eurasia and North America, favoring lowland woodland while avoiding the most acidic or the most calcareous ground.