Deadwood is not mess — it is habitat

A fallen branch left across a woodland ride, a stump quietly rotting beside a hedge, a hollowing oak still standing on the edge of a field: these are among the richest wildlife features in the British landscape. Deadwood is not the sad end of a tree. It is the start of an entire food web, one that has been evolving alongside our woods since the last Ice Age, and one that is remarkably easy to bring back.

Around 1,700 species of British invertebrates depend on dead or decaying wood for at least part of their life cycle. Add the fungi that break the wood down, the mosses and lichens that follow, and the birds, bats and small mammals that feed among them, and you have a habitat that punches far above its weight.

What actually lives in a rotting log

A single oak log in a damp corner of a Shropshire wood can hold more species than a whole field of improved pasture. The cast list is varied, and often surprising.

• Beetles: Stag beetle larvae spend three to seven years chewing through buried, crumbling wood in southern and south-eastern England. Lesser stag beetles, rhinoceros beetles and longhorn beetles do similar work at smaller scales.
• Fungi: Beefsteak fungus spills its rusty flesh over old oak; chicken-of-the-woods glows sulphur-yellow on beech; purplepore bracket and candle-snuff fungus each arrive at a different stage of decay. Some species are so specialised that they occur on a single tree species.
• Birds: Great spotted woodpeckers chisel out grubs, nuthatches and marsh tits cache seed in crevices, and treecreepers probe softened bark. Rotting stumps often offer the easiest excavation for a nest hole.
• Bats and mammals: Bats roost in cracks in standing deadwood, while hedgehogs, voles and slow worms use log piles as shelter and as a warm place to hibernate.

Why our woodlands ran short of it

For a century and more, the tradition has been to tidy up. Fallen timber has been extracted, dead trees felled on sight, and wood pasture with its ancient, hollowing veterans largely lost. In a truly natural wood, dead wood might make up a fifth or more of the standing volume. In many of ours it is one or two per cent — and much of that is in uniform, freshly cut pieces that rot too fast, or too dry, to suit the specialists.

The wildlife is still out there, surviving in fragments. Give it wood of the right kind, in the right place, and it usually turns up within a few years.

How to leave deadwood well

Leaving timber in place is easy; leaving it sensibly takes a little thought. Safety comes first, and a few simple habits make the rest straightforward.

• Assess standing trees properly. If a dead tree leans over a path, road or building, ask a qualified arboriculturist about reducing it to a monolith — a stout stump of two or three metres. That keeps most of the habitat value and removes the risk.
• Site log piles in shade. Damp is the whole point. Part-bury the bottom logs, keep the bark on, and stack them loosely rather than tightly so rain and air can get in.
• Mix your material. Oak and beech rot slowly, birch and ash quickly. Vary the diameter too, from finger-thin branches to logs a foot across, because different species move in at different stages. Variety beats volume every time.
• Leave some snags standing. A dead trunk with a hollow top is prime estate for bats and hole-nesting birds.
• Keep deadwood local. Many saproxylic beetles travel only metres in a lifetime, so timber carted in from across the county is unlikely to be recolonised.
• Check before you burn. Build bonfire material fresh rather than leaving it to sit for months, and lift and turn it before lighting. Hedgehogs, frogs and slow worms will thank you.

Small garden, real difference

You do not need a wood. A space about three metres by one metre in a shady corner will do handsomely. Sink a few logs upright to make a miniature stumpery, or simply lay three or four pieces of different species on the ground and let them lie. Add a bucket of woodchip nearby for hoverflies and solitary bees, and leave the leaf litter beneath your hedges where it falls. Even a single decaying stump in a suburban garden will draw beetles and fungi, and eventually its own woodpecker.

Do keep piles away from doors, paths and play areas, and don't feel obliged to inspect them at close quarters — a log pile left undisturbed for years may hold a wasp nest, which is a sign of health rather than a problem.

Patience, and what you will see

The first year, a new log pile looks like little more than a pile of logs. By the second, you will find beetles under loosening bark and a flush of fungus after autumn rain. By the third, the wood is soft enough to crumble in your hand, and something has clearly been digging. That is the point of it: deadwood is not a monument to a tree, but the slow, bustling, brilliant business of turning one generation of woodland into the next.