Polytrichum commune (Syn: Polytrichum uliginosum) (NL: Gewoon haarmos / EN: Common Haircap / DE: Goldenes Frauenhaarmoos / FR: Polytrichum commune) can be found in a wide range of damp, acidic habitats, tolerating shade and moderate amounts of pollution and nutrient enrichment. The species is well-grown, large and hummocks or turfs of this species are unmistakable. They consist of tough, wiry shoots up to 40 cm long (usually about 20 cm). When moist, the 8–12 mm long, narrowly spearhead-shaped leaves spread or strongly curve away from the stem, with a glossy sheathing base, giving a starry appearance viewed from above. When dry, the margins become inrolled, wavy and gently twist around the stems. The margins are sharply toothed and the broad nerve is covered with up to 70 ridges of tissue. The leaves surrounding the base of the seta are longly tapering and toothed above. The 4-angled, box-like capsule, produced in summer, is borne on a long (to 12 cm), reddish seta. It is erect when young, becoming inclined to horizontal with age; its lid is shortly beaked. The young capsule is covered by a long, golden brown, hairy calyptra.
In this image the capusles are still young and the moss is rather dry.

Image: Malle (BE) - 26/03/2013