Why a stack of old logs is worth the space

Dead wood is one of the scarcest habitats in Britain. In a truly wild wood, a good share of the timber on the ground is standing dead, fallen or quietly rotting, and that material supports an enormous web of life. In most gardens we tidy every fallen branch away, so beetles, fungi and amphibians have nowhere to go. A log pile puts a bit of that back. It is free, it takes an afternoon, and within a season you will have tenants you have never seen before. Unlike a pond or a hedge, it needs almost no maintenance at all — the whole point is to leave it alone.

Choosing the right spot

Position matters more than the logs themselves. Aim for dappled shade: the edge of a hedge, under an apple tree, beside a shed wall that only catches morning sun. Full sun bakes the wood and dries it out; deep shade keeps it cold and slow to rot. Damp and half-shaded is the sweet spot.

Other things to weigh up:

• Put it near a pond or a boggy corner if you can — frogs, toads and newts will use it as a daytime refuge only a short hop from water.
• Keep it a metre or so away from house walls and fences, so damp does not travel into timber or masonry.
• Sink the bottom layer slightly into the soil, or press it into the lawn, to hold moisture in.
• Avoid spots that flood in winter or that sit on solid paving.
• If you want a second, smaller pile, put that one in full sun for bees and basking reptiles.

Which woods work best

Any untreated timber will rot down and be used, but some is better than others.

• Best: oak, beech, ash, hornbeam, birch, apple, pear, cherry, hawthorn and sycamore. These are hard, hold their shape for years and rot slowly, which gives a long-lasting home.
• Good and quick: willow, poplar and alder. They break down in two or three years, feeding fungi and beetles fast.
• Perfectly fine: conifer logs, though they are more acidic and slower to colonise.
• Avoid: anything treated with preservative, creosote or stain, plus MDF, chipboard, plywood, painted or varnished timber, and old railway sleepers. These release chemicals that do more harm than good.

Size-wise, logs about 10–30cm across are ideal — thick enough to stay damp inside, small enough to handle. Leave the bark on. A mix of diameters is better than a uniform load, because different beetles want different thicknesses of timber.

Building the pile

Start with the thickest logs on the ground and stack upwards in a loose criss-cross, like a stack of firewood that has given up being tidy. Gaps are the point: they create the tunnels, chambers and humid pockets that invertebrates need.

• Fill the gaps with smaller branches, twigs, bark peelings and a few handfuls of leaf litter.
• Aim for roughly 50–100cm high and about a metre across. Bigger is better if you have the wood.
• Sink two or three logs upright into the soil nearby, half-buried. Stag beetle larvae need buried, rotting wood to feed in.
• Pile fallen leaves around the base and let them stay there.
• If you want to help solitary bees, take one dry log, drill holes 2–10mm wide and about 10cm deep into the end grain, and stand it somewhere sheltered and sunny.

Do not use nails, wire or plastic sheeting to hold it together. If it collapses, that is a feature, not a fault.

Who moves in

The first arrivals are usually woodlice, millipedes, centipedes, earwigs and spiders. Then come the beetles: lesser stag beetles, click beetles, bark beetles and, if you are lucky and in the right part of southern England, the great stag beetle itself. Frogs, toads, slow worms and hedgehogs will use the pile to shelter or hibernate, and queen bumblebees often tuck into the base to wait out the winter. Look for fungi too — King Alfred's cakes, candle snuff and sulphur tuft are all signs that the wood is being broken down properly.

Leaving it alone

Once built, the pile needs nothing from you except patience. Do not top it up with fresh garden waste, do not burn it, and try not to move it between October and March, when something is almost certainly asleep inside. If you really must shift it, do it in late April or May on a mild day, and check slowly for hedgehogs and frogs as you go.

Add a few more logs each autumn as the old ones sink, and within three or four years you will have a soft, crumbly, teeming heap at the bottom and a hard, dry, hollow one on top — two habitats for the price of one.