Country diary: Winter finally comes to these woods

Finally, a winter’s day that actually feels like one! Crisp air, blue sky, frost – just what the doctor ordered. For months, it has felt as if the Earth itself has been suffering from a low-grade fever – it was a depressingly record-breaking 16C on New Year’s Day and has been grumbling along in low double figures ever since.

Today, though, the icy air quickens the blood, tautens everything with its astringent sting. I want to feel it against my skin, as you might test a knife’s sharpness with your thumb. At Staple Hill, the footpath skirts the edge of conifer plantations: mostly Scots pine, Norway spruce and the occasional magnificent cedar. There are also oaks, beech and silver birch, and under the trees a tussocky jumble of bracken, moss and brambles. The whole area is a delightful patchwork of evergreen and deciduous, straight rows and rambling woodland, tarmacked pathways and animal tracks, open glades and spooky fairytale forests where a gruffalo would feel right at home.

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The tree trunks look painted in colours squeezed fresh from the tube. A trick of the eye? Surely this much iridescent green belongs in the summer and in the leaves of the canopy, not on the trunks and branches of the naked trees? Lichen reigns supreme at this time of year, in every shade of jade, emerald, pistachio and chartreuse. Each variety is the result of a particular blend of fungus, bacteria and algae.

The sun has been out all day, but in the dips and shadows, frost still lingers. Tiny white globules adorn each blade of grass. I pick one up expecting it to crumble, deliquesce or pop, but it stays on the tip of my finger: a pearl of solid water, supercooled dew. I put it in my mouth and it melts deliciously on my tongue.

I cross a glade of plantation trees, their tall shadows spreading on the grass as precise as a barcode, and enter the forest. Fallen pine needles cushion the ground, putting a spring in my step. The air is drenched with phytoncides. I can almost feel my immune system bucking up.

My walk back is a slow strobe – two steps dark, two steps dazzle – as though the sun has decided this perfect crystal day deserves nothing less than to end in a blaze of glory.

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