This is a small moss with a very long name. P. hornschuchianum is a common member of a classic community of small mosses found on well-drained open base-rich ground, for example in gateways and the edge of tracks. Its associates include Bryum argenteum, B. dichotomum, Dicranella varia, Brachythecium mildeanum and Cratoneuron filicinum. It is also very often found with two mosses of the same bright green colour – Barbula unguiculata and Streblotrichum (Barbula) convolutum.
Its leaves are very sharp-looking and make plants look spiky. Although the leaf margins are revolute, when you view leaves from above with a lens, because the laminar edges are raised, the margins actually look inrolled, a little like a Weissia.Read the Field Guide account