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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