Kneel to pull a soft, spongy handful from a tired lawn and this is very often the moss you are holding. Springy turf-moss is the bryophyte most gardeners meet before any other, the loose green stuffing that gathers in damp, shaded grass until the turf gives like a mattress underfoot.
Knowing it on sight
The look is shaggy and star-like. Stout shoots, tinged red or orange-brown along the stem, carry small leaves that bend sharply outward and back, standing away from the stem at almost a right angle so that each shoot bristles like a little bottlebrush. That spreading set of the leaves gives the plant its scientific name, squarrosus meaning turned back at the tip, and it is the surest field mark. The shoots branch loosely rather than in the neat herringbone of the true feather mosses, building a coarse, open, decidedly untidy mat that springs back when you press it. Colour runs from yellow-green to a tired olive depending on light and season.
Where it turns up
Grassland is its home ground. You meet it through lawns and playing fields, in old meadows and on grassy banks, along woodland rides, in churchyards and across the damp hollows of dune systems, right across the cooler temperate world. Unlike many mosses it tolerates a degree of nourishment and will sit happily in grass that has been fed, favouring ground that is neutral to mildly acid and, above all, reliably moist. Light it is easy about, taking open sun where the ground stays damp and shade just as readily.
The lawn invader
No other moss is so tied to lawns, and the reason is that springy turf-moss flourishes in precisely the conditions that leave grass weak. Shade beneath trees and walls, soil packed hard underfoot, a surface that stays sodden, mowing too close and a hungry, sour root-run all thin the sward and open gaps, and this moss moves straight into them. So a lawn turning spongy with it is really reporting on its own ground, a point worked through in moss in the lawn. Blacken it with iron sulphate, as the boxed lawn treatments do, and it darkens within days, yet it returns the moment the underlying damp and shade reassert themselves, which is why removing moss for good means changing the conditions and not merely the moss.
From nuisance to lawn
The same vigour that frustrates the lawn-keeper makes this one of the better mosses to grow on purpose. Because it creeps and branches into continuous, walkable cover rather than sitting in slow tight domes, it knits into a soft green sheet that takes light foot traffic, stays green through winter and drought, and never needs a mower. Where grass has long given up under a tree, letting the turf-moss take the whole patch is frequently the easier and the handsomer choice, and it is one of the carpet-formers leaned on in how to make a moss lawn. A springy turf-moss lawn asks chiefly that you keep autumn leaves swept off it.
Working with it or against it
Whichever side you take, it helps to know what kind of moss you are dealing with. Springy turf-moss is a creeping, branching pleurocarp, the sprawling habit set against the upright cushions in acrocarpous and pleurocarpous mosses, and that spreading growth is exactly why it covers ground so well and why it shrugs off half-hearted raking. To favour the grass, lift the shade, ease the compaction, raise the mower and feed; to favour the moss, do the opposite and simply let the damp shade have its way. Either path works, so long as you commit to one.