What is Larch?
The Wood Guide · The wood register
Softwood · referenceLarch
A conifer that goes bare in autumn — the bridge between conifers and broadleaf trees. And the most resinous, most durable wood that Europe's coniferous forests produce.
- Genus Larix
- Up to 40 m tall
- Class 3 — without pressure treatment
European larchLarix decidua
Larch in brief
Family Pinaceae, and the exception within it: larch is the only common conifer that drops its needles in winter.
Shedding its needles is more than a curiosity. It allows the tree to survive extremely cold winters, and it explains why larch grows from the Alps to Siberia. Trees reach 40 metres, with trunk diameters of up to a metre at breast height.
The wood is resinous and dense, with a warm honey to reddish-brown colour. Of the common European softwoods, it is the only one besides Douglas fir to reach durability class 3 — usable outdoors without pressure treatment, at least above ground.
The geographical spread is wide, and you can see it in the wood. Slower-grown Siberian larch has narrower rings and a higher density than fast-grown European or Japanese larch from a plantation.
- European larch
- Larix decidua Mill.
- Siberian larch
- Larix sibirica, Larix gmelinii
- American larch
- Larix laricina, Larix occidentalis
- Japanese larch
- Larix kaempferi
- Dimensions
- up to 40 m tall, up to 1 m in diameter
- Durability
- class 3
To be fair: larch bleeds resin. The wood contains a lot of resin that can run out of knots in warm weather, and it comes through paint and stain. For painted work a stain-blocking primer is no luxury, and on decking in full sun it means sticky patches on hot days.
A conifer that goes bare
Larch is the only common conifer that drops its needles in winter: in autumn they turn golden yellow and fall. That lets the tree survive extremely cold winters — and explains why larch grows from the Alps to Siberia.
Click a chapter or use the arrows · ring widths and trees schematic.
The four larches
| Species | Botanical | Origin and character |
|---|---|---|
| European larch | Larix decidua | Alps and Central Europe; the most common one here |
| Siberian larch | Larix sibirica, L. gmelinii | Russia; slow-grown, denser and more durable |
| American larch | Larix laricina, L. occidentalis | North America; western larch is the heaviest |
| Japanese larch | Larix kaempferi | Widely planted in Europe; faster-grown, wider rings |
Siberian larch is noticeably denser and more durable than fast-grown Japanese larch from a European plantation, yet both are simply sold as "larch". For cladding that has to last thirty years, that difference is worth asking about.
What sets larch apart
Resinous
The resin acts as natural protection against moisture and insects — one of the reasons for class 3.
Dense for a softwood
Around 590 kg/m³, heavier than spruce (450) and pine (520). You notice that in the strength and in the weight.
Warm colour
Honey to reddish-brown heartwood with clearly lighter sapwood. Outdoors it weathers to silver grey.
Deciduous
The only common conifer that goes into winter bare — the reason it grows as far as Siberia.
Class 3 means ten to fifteen years outdoors, but not in the ground. Posts and beams that touch the soil should be pressure-treated or made from a class 1 species. See pressure-treated wood.
What larch is used for
Cladding
Its strongest use: durable enough without treatment, weathering attractively, and fitted vertically the water runs straight off.
Garden timber
Fences, decks and pergolas — more than adequate above ground.
Construction
Stronger than spruce, and in mountain building traditionally the wood for roof trusses and timber frames.
Shipbuilding
A classic choice for hull planking, thanks to its combination of strength and rot resistance.
Both class 3, both usable without pressure treatment. Larch is more resinous and slightly heavier; Douglas fir is calmer in appearance and easier to finish. The full comparison is on larch versus Douglas fir.
Frequently asked questions about larch
Does larch really lose its needles?
Yes. It is the only common conifer that does: in autumn the needles turn golden yellow and fall. Botanically it is still a conifer — the leaf shape and the cones determine the group.
Can larch be used outdoors without treatment?
Above ground, yes, in durability class 3. In ground contact, no: that calls for pressure-treated wood or a class 1 species.
Why is resin leaking from my larch cladding?
Larch is resinous, and in warm weather resin can run out of knots. That is normal and stops after a few seasons. You can wipe off fresh resin with a little white spirit.
What is the difference between larch and mélèze?
None — mélèze is the French name for larch. See our mélèze page for the same species under its French trade name.
Larch in perspective
Europe's most durable common softwood — and the only one that goes into winter bare.
Have a question about your project? Just ask — we're happy to help.
Larix decidua — Philipp Zinger, CC BY-SA 4.0 · Larix decidua — Lumbar, Public domain · Larix sibirica — Cheburgenator, CC BY-SA 4.0 · Photo via Wikimedia Commons: Larix decidua — Uoaei1, CC BY-SA 4.0