Elm - Wych Elm - Ulmus glabra
Uses: Most commonly used in
furniture making (particularly so for burr elm), but can also be used
for interior joinery and for cladding. Elm is very popular with people
who like a natural, wild figure in their wood. It’s also used widely
for turnery and small decorative articles. Elm was once used for
coffins and for boat building - although only for those parts of the
vessel that would be wholly submerged as it’s durable if kept
completely wet.
Scottish Elm: Scottish elm is more
widely available that elm in many other parts of the country due to the
effects of Dutch elm disease. Scottish elm tends to have a wilder
figure and grain than that grown south of the border.
Strength and Structure
Grain: Elm tends to be cross grained, but wych elm is generally straighter grained than English or Dutch.
Density: Around 670 kg per cubic meter at 12 per cent moisture content (compared with 550 kg/m3 for English and Dutch elm).
Structure: Elm has a ring porous
structure with distinct growth rings demarcated by a pore ring of early
wood vessels. Late wood vessels are small and indistinguisheable. Rays
are fine and parenchyma indistinct.
Strength: Not a particularly strong
timber, although wych elm (most common in Scotland) has higher strength
that other species. Wych elm has medium bending and crushing strength
and shock resistance, with low stiffness. English and Dutch elm have
low or very low strength on all these measures.
Durability & Drying: Dries rapidly but with a marked tendency to distort. It doesn’t tend to split or check, but may collapse.
Colour & Figure: Elm is a
colourful timber. The heartwood can be a dull brown of various shades,
but elm often has other colours running through it, especially purples
and greens. The figure of the timber also varies. The figure of plain
elm is dominated by the pattern that arises from contrasting early and
late growth, but elm also has patches of irregular grain. Elm often has
cats paws and other markings. Burr elm is highly valued for its
appearance. Sapwood is distinct from heartwood.
Working Properties:
Machines well, unless grain is irregular. Has
moderate blunting effect and generally saws satisfactorily. Nails,
glues and finishes well.
The Tree
Looks and Leaves: The tree can reach
a height of 38-45 metres. The bark of the young trees is very smooth,
becoming fissured only after the tree has reached a reasonable age.
Branches tend to extend a great distance in trees that grow in
isolation, but in woodland trees, the tree will develop a dome crown on
a fairly clear bole. The flowers open in February and March, with fruit
developing before the leaves emerge. Twigs bear 2 rows of bright green
leaves that are quite hairy, broadest just beyond the middle with the
tip drawn out. They turn yellow before falling.
Habitat: Common in hillside woods in
the Highlands wherever it is shady and damp. Tallest and finest trees
grow in sheltered glens in deep moist soils.
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