Larch

Larch

Larix decidua
Other names: European Larch

General description

Larch is a typical tree found in the Alp mountains in Central Europe with a straight trunk. It grows to a height of about 40 m with diameters ranging from 40 – 70 cm.

Wood description

Sapwood is thin, from 1 to 3 cm and yellow. The clearly demarcated heartwood is light brown to dark red brown and can vary largely, depending on origin and growth conditions. The texture is fine to medium according to growing speed.
The resin canals are smaller than in Pine, but do occur as often.
Softwood shows medium to high density and very good strength properties. Gluing properties are good, if the wood is technically dried, but due to resins it can be more difficult, if the wood is not dried. Sawing properties are good, but due to resin clogging of saw blades may occur. Nailing and screwing properties are good, but pre-boring is necessary.

Common uses

Larch is used for heavy carpentry, exterior paneling, exterior and interior joinery and also for flooring.

Physical characteristics
Density (at 12 % moisture content) 583 kg⁄m3
Total longitudinal shrinkage 0.3 %
Total radial shrinkage 3.3 %
Total tangential shrinkage 7.8 %
Equilibrium moisture content  
(20° C⁄ 37 % rel. humidity) 8.4 %
(20° C⁄ 83 % rel. humidity) 17.1 %
Mechanical characteristics
Modulus of elasticity under bending 13800 N⁄mm2
Modulus of rupture under bending 99 N⁄mm2
Tension strength 107 N⁄mm2
Compression strength 55 N⁄mm2
Brinell hardness perpendicular to the fibres 19 N⁄mm2
Janka Hardness 2,5 kN
Nail withdrawal strength in N per mm depth and mm diameter 12 N⁄mm2
Natural durability and treatability (according to en 350-2)
Fungi Class 3 – 4 moderately to poorly durable
Dry wood borers durable
Termites Class S susceptible
Treatability 4 – not permeable

Natural durability is based on mature heartwood. Sapwood must always be considered as non durable against wood destroying agents.