Polytrichum commune (also known as Common haircap moss, Common hair moss, great gold headed or Great Goldilocks) is a species of moss found in many regions with high humidity and rainfall.

These are also the constant species, together with the moss Polytrichum commune.

Polytrichum commune is a medium to large moss.

Polytrichum commune is an endohydric moss, meaning water must be conducted from the base of the plant.

While mosses are considered non-vascular plants, Polytrichum commune shows clear differentiation of water conducting tissue.

Polytrichum commune var.

Defined by constant Carex echinata, the Sphagnum species and the moss Polytrichum commune.

Common Haircap (Polytrichum commune)

It supports a number of plant communities and a diversity of plant species including cotton grass, bottle sedge and various mosses, especially Polytrichum commune.

The high humidity helps mosses survive underneath including Campylopus flexuosus, Hypnum cupressiforme, Polytrichum commune, Pseudoscelopodium purum and Rhytidiadelphus squarrosus.

Polytrichum commune (also known as Common haircap moss, Common hair moss, great gold headed or Great Goldilocks) is a species of moss found in many regions with high humidity and rainfall.

The Polytrichopsida differ from other mosses in other details of their development and anatomy too, and can also become larger than most other mosses, with e.g. Polytrichum commune forming cushions up to 40 cm (16 in) high.