Clare's firwood is a small refuge. Outside, there is storm, frost and snow. Under the evergreens, a narrow path runs through a pocket of calm where even a weed stays green. The central idea is that these humble trees, with their needles standing in for leaves, can turn winter into something close to summer. The poem makes this claim carefully, and its honesty is part of its charm.
The key word is "almost," which turns up three times. The trees soften "the roughest tempest almost calm," the loudest winds are "almost as summer's breath," and in the last line "Winter is almost summer where they grow." Clare never pretends the firwood abolishes the season. He measures a gap and lets us see how narrow it has become. Against that cautious word, "ever still and warm" sounds like a small outburst of gratitude, and "rich" appears twice, once in the colour of the trees in line 2 and again in the final couplet. That repetition frames the poem with wealth, which is a surprising thing to find in a bare winter wood.
The form is plain and neat. There are six rhyming couplets in a loose iambic pentameter, and the rhymes are mostly full and unfussy: wear/year, calm/warm, below/snow, show/grow. The exception is "underneath" and "breath," which only half rhyme, and the slight give in the sound suits a line about wind slipping gently through. The most interesting rhythmic moment is line 8, "When others out of doors are lost in frost and snow." It runs to six beats instead of five, so it stretches beyond the pattern just as the snow stretches over the open fields. The phrase "out of doors" also quietly turns the firwood into a house. The trees become a sheltered interior, and everything else is left outside.
The syntax supports this. The first eight lines make one long sentence that unrolls the way the shelter does, from the trees to the path to the weed to the world beyond. Then the poem turns, with "And sweet the music trembles on the ear," and moves from sight and touch to sound. The wind "suthers" through "each tiny spear." Clare's dialect word seems, judging by the context, to describe a soft rushing or sighing, and its hushing consonants do that work themselves. "Spear" is a sharp word, yet here the needles are not weapons but instruments, and the wind plays them. A similar oddity is the verb "towels" in line 5, which I cannot pin down with confidence. Within the sentence, it seems to describe the path running or trailing beneath the trees.
The pivot comes in line 11: "Makeshifts for leaves; and yet, so rich they show." Clare concedes the objection before anyone can raise it. Needles are a poor substitute for real leaves, "makeshifts," and then the "and yet" overturns that judgement. The poem has been moving toward this reversal from the first line, where the trees "taper into twigs" and so seem thin and reduced, but "wear / The rich blue green of summer," as if putting on a coat. Wearing is a good verb for evergreens. It suggests colour that is chosen and kept, not simply grown.
What makes the poem significant is where it looks. Clare gives his attention to a narrow path and a green weed, small things that most poems about winter would overlook in favour of the storm. The weed is the best detail in the poem. It "lingers," as if it has been quietly allowed to stay, and the loudest winds "scarce fan" it. Nothing dramatic happens in these twelve lines, and that is the point. The poem finds comfort in the ordinary, in what survives and what shelters, and it describes that comfort exactly, no more generously than it deserves. For a reader used to nature poems that rise to grand statements, Clare's modest "almost" is a quiet and convincing alternative.