Dahurian Larch, also known as Asian larch, is a species of larch native
to eastern Siberia, and adjacent northeastern Mongolia, northeastern China
(Heilongjiang) and North Korea. It forms enormous forests in the eastern
Siberian taiga, growing at 50-1,200 meters in altitude on both boggy and
well-drained soils, including on the shallow soils above permafrost.
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It is unique in two respects, being the northernmost tree in the world,
reaching 72° 30' N at Ary-Mas (102° 27' E) in the Khatanga River
valley on the Taymyr Peninsula, and also the most cold-hardy tree in the
world, tolerating temperatures below -70 °C in the Oymyakon–Verkhoyansk
region of Yakutia. One tree in Yakutia is known to have been 919 years
old.
It is a medium-sized deciduous coniferous tree reaching 10-30 m tall,
rarely 40 m, with a trunk up to 1 m diameter.
The wood:
- has
a medium to fine texture, with a silvery cast and an oily feel
- lacks
a distinctive odor or taste
- has
sapwood which is white and narrow (less than 1" wide), and sharply
differentiated from the heartwood
- has
resinous heartwood which is yellow to russet brown (sometimes described
as pale reddish-brown to brick-red)
- is
intermediate in strength, stiffness, and hardness, while moderately
high in shock resistance
- has
a specific gravity of .49 green to .53 dry
- generally
works well
- has
a noticeable blunting effect on tool
- has
a tendency to split when nailed
- is
low in paint retention.
The
wood of larch looks much like the wood of pine, especially in its dry
condition.The lines of the annual ring are very sharp and are clearly
seen by the difference in colour between the light early wood and dark
late wood.
Compared to Norway spruce, larch is seen as rather difficult to work with
because of:
- bad
stem form
- spiral
grain
- higher
density
- larger
amount of latewood
- harder
latewood
- dry
knots
- thicker
bark.
Larch
can have a tendency to split in nailing. Pre-boring is therefore recommended.
Iron nails and screws corrode only weakly in the heartwood of larch, because
of little acid in the heartwood.
Larch is easily glued, except when a high content of resin is present.
It has similar properties to Scots pine, which means that wood with large
contents of resins can cause some problems. It is therefore recommended
to pre-treat the wood with a resin-dissolving product, especially if it
is exposed to high temperatures.
Larch
wood is used when high strength, hardness and durability needed, like
in building of mines, bridges, and heavy constructions. Larch can without
serious problems be worked on with all manual and mechanical tools. When
dry, the wood is relatively easy to work, though growth stresses and compression
wood can cause some problems.
Problems can occur in the sawing process because of the high amount of
resin,especially in fresh wood.The problem can be solved by lubricating
the saw blade with water or light oil, or by sawing the wood in frozen
condition.
Density
= 520-640 kg/m3
Radial shrinkage = 2.3% - 3.3%
Tangential shrinkage = 4-6%
Heartwood
in European larch is almost totally resistant to pressure impregnation.
The sapwood is moderately resistant or satisfactory.
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