he morning air is cold and grey with moisture. Rain patters on the soft, brown leaves and muddy paths between the trees. The woods and heathland seem silent at first, but when I stop and listen, I hear the soft whistles and seeps of small birds – great tits, blue tits, long-tailed tits, goldcrests – roaming through the branches above, looking for food. Four squirrels chase each other like carriages in a toy train, weaving between the trunks, before they scramble up an oak tree and disappear in the canopy. A nuthatch lurches along the bough of another oak. It leaps across to a neighbouring tree, squealing and flapping its broad, grey wings. Another nuthatch rises to meet it, shrieking, and the two birds briefly lock their feet mid-air in combat. Then the second bird retreats and flies off. The first returns to looking for insects and grubs, probing the bark. I continue uphill, past the spiky, upward-sprouting clumps of coppiced birch and hazel. The traditional technique of coppicing on the reserve provides sustainable wood products and also allows light and warmth to reach the ground, encouraging smaller plants and insects to thrive, until the trees grow dense and are harvested once again. At my feet are clumps of a shrubby “reindeer moss”, which is really a type of Cladonia lichen, with pale grey, intricate coral-shaped branches – a specialist of the acid soil found here. Some of the clumps are attached to decaying twigs and trunks, others are growing directly in the soil. More types of lichen, with grey-green scales, cover the trees by the path. The lichens are formed by a symbiosis of a fungus and one or more photosynthetic partners – algae or cyanobacteria – which produce the carbon that the fungi need in the form of simple sugars. In the clearing ahead, two young brown fallow deer look up from grazing to stare at me. Behind them, Highland cattle emerge from the tall pines, also munching on the thin vegetation. The deer wait for several minutes, weighing me up, before running into the woods. A raven flies towards me and passes low over my head, its deep, harsh bark echoing across the heath.