Kneel almost anywhere in a shaded British garden, or in a patch of damp woodland, ease the leaf litter aside, and the pale straggling moss laced through it is very often common feather-moss. It ranks among the most abundant bryophytes of the lowlands, running over soil, logs and the shaded feet of walls, yet, being neither bright nor tidy, it passes most eyes without ever collecting a name.
A pale, feathery sprawl
This moss grows in loose, rambling mats of soft pale green, tending to yellowish where a little light reaches it and darkening in deep shade. Hold a length up to the window and it looks matt rather than varnished, a first impression that quietly separates it from the shinier mosses it grows among. The shoots branch in a fairly even, comb-like way, sending side branches off at wide angles, so a well-grown piece really does carry the outline of a small green feather, which is where its name comes to rest. It creeps flat and pegs down here and there by its rhizoids, one of the branching carpet mosses set out in acrocarpous and pleurocarpous mosses.
The two kinds of leaf
What clinches the name rewards a hand lens, and it is unusually clear-cut. The leaves come in two shapes on the one plant. Those clothing the main creeping stems are broad and heart-shaped, close to triangular, and pull up abruptly into a long slender point; those on the fine side branches are much smaller and narrower, a tidy oval drawn out to a tip. This sharp contrast between stem and branch leaves is uncommon among the sprawling mosses alongside it, and it is the most dependable single feature for a name. A faint nerve runs perhaps two-thirds of the way up each leaf. Through autumn and winter the plant may raise curved capsules on thin red-brown stalks that feel minutely rough when you draw a fingertip down them, though it fruits sparingly, so you cannot rely on finding any.
Telling it from its lookalikes
Two other common mats cause most of the muddle. Rough-stalked feather-moss, given its own account in rough-stalked feather-moss, is glossier and a deeper green, its leaves much of a muchness along the whole plant without that stem-and-branch contrast; where common feather-moss reads matt and faintly greyish, its rival gleams. Plait moss shines more still and sweeps every leaf to one side like combed wet hair, something common feather-moss never does. Faced with doubt, wet a scrap, tilt it to the light for the matt-or-shiny test, then hunt for the two leaf shapes; taken together they seldom mislead. Sorting the sprawling mosses in general is the subject of how to identify moss.
Almost anywhere shaded and damp
Little troubles this moss about a home. It sheets over bare shaded soil, threads through leaf litter and humus, climbs the moist bases of trees and hedge banks, cloaks rotting logs and old stumps, and works into lawns, border edges and the gravel of paths that see few feet. Shade and a steady dampness are about all it asks; past that it is thoroughly easy-going, and, like its glossy neighbour, it puts up with the nitrogen of fertile, dug-over and cultivated ground that would sour many choosier species. That tolerance, joined to brisk growth, is why it appears so dependably in gardens, on allotments and along the trodden margins of woodland rides across Britain and much of temperate Europe.
Its quiet work in the wood
Underfoot in a wood this unremarkable moss does more than its looks suggest. Quick to spread across disturbed or freshly opened ground, it knits loose leaf litter and fine soil into a stable green skin that holds the surface against rain-wash while slower plants find their feet, and its damp mats house the springtails, mites and other minute creatures gathered up in the hidden world in a moss cushion. In a garden it asks nothing and spoils nothing; where it strays into a lawn it is merely reporting the damp shade that admits any lawn moss, a case weighed in making, or unmaking, a moss lawn. Should you want it on purpose, for the soft floor of a shaded bed or the aged look of a stumpery, there is rarely any need to plant it: leave a patch of damp, shaded bare soil undisturbed and keep it from drying, and within a season or two it is usually threaded through of its own accord.