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Elm, Common
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Elm, Common
Where To Found It: Britain (not indigenous),
Europe, Asia, North Africa.
The Elms belong to the natural order Ulmaceae and to the genus
Ulmus, which contains sixteen species, widely distributed throughout
the north temperate zone, extending southwards as far as Mexico
in the New World and the Sikkim Himalayas in the Old World.
The Common Elm (U. campestris, Linn.) is a doubtful native
of England, found throughout the greater part of Europe, in North
Africa, Asia Minor and eastwards to Japan.
It grows in woods and hedgerows, especially in the southern part
of Britain and on almost all soils, thriving even in the smoky atmosphere
of a city, but on a rich loam, in open, low-lying situations, attaining
a height of 60 to 100 feet, even rising to 130 and 150 feet. In
the first ten years of its growth the tree grows to 25 or 30 feet.
The branches are numerous and spreading, the bark rugged, the
leaves alternate, ovate rough, doubly toothed and unequal at the
base. The flowers are small and numerous appearing in March and
April before the leaves, in purplish-brown tufts. If one of these
tufts be examined, it will be found to be a short axis with a number
of leaves, beginning two-ranked at the base, and going over to five-ranked
above. There are no flowers in the axils of the lowest ten or twelve,
in the axils of the upper leaves are flowers arranged in small cymes
(in some species), but in U. campestris reduced to the one
central flower. Each flower has a four-toothed, bell-shaped calyx
surrounding four stamens and a onecelled ovary bearing two spreading
hairy styles.
The seed-vessels are green, membraneous, one-seeded and deeply
cleft, but the tree seldom perfects its seed in England, being propagated
by root-suckers from old trees, or by layers from stools.
In age and size, the Elm closely approaches the Oak, but is more
varied, a large number of named varieties being grown.
All parts of the tree, including sapwood, are used in carpentry.
The wood is close-grained, free from knots, hard and tough, and
not subject to splitting, but it does not take a high polish. It
does not crack when once seasoned and is remarkably durable under
water, being specially adapted for any purpose which requires exposure
to wet. To prevent shrinking and warping in drying, it may be preserved
in water or mud, but is best worked up soon after felling. In drying,
the wood loses over 60 per cent of its weight.
Elm wood is used for keels and bilge planks, the blocks and dead
eyes of rigging and ship's pumps, for coffins, wheels, furniture,
turned articles and general carpenter's work. Elm boards are largely
used for lining the interior of carts, wagons and wheelbarrows on
account of the extreme toughness of the wood, and it has been much
employed in the past for making sheds, most of the existing farm
buildings being covered with elm. Previous to the common employment
of cast-iron, Elm was very much in use for waterpipes.
The inner bark is very tough and is made into mats and ropes.
The leaves and young shoots have been found a suitable food for
live stock.
Investigations are at present being carried on as to the cause
of a mysterious disease, known as the Dutch Elm disease, which is
killing trees on many parts of the Continent. It first appeared
in North Brabant in 1919, and spread until it is now all over Holland.
By 1921, the disease was rampant in Belgium and in the same year
it appeared in France, while in 1924 and 1925 it spread widely in
Germany and it is also working havoc in Spain.
The first sign of the disease in trees up to thirty years old
is a mass of dry twigs and leaves in the crown while the other parts
are still green. Within a week, all the leaves of the tree may fall,
or the leaves on one side of the tree may remain fresh, while on
the other side they fall off. No cure has yet been discovered, and
the tree eventually dies. Most investigators consider that the disease
is caused by a fungus (Graphium ulmus), the infection being
carried by spores blown from one tree to another.
To prevent the importation into Britain of this mysterious disease,
the Ministry of Agriculture, early in 1927, prohibited live elms
from the European mainland from being landed in England and Wales.
Analyses of Elm wood show 47.8 per cent of lime, 21.9 of potash
and 13.7 of soda.
A peculiar vegetable principle, called Ulmin or Ulmic Acid, was
first discovered in the gummy substance which spontaneously exudes
in summer from the bark of the Common Elm, becoming by the action
of the air a dark-brown, almost black substance, without smell or
taste, insoluble in cold sparingly soluble in boiling water, which
it colours yellowish-brown, soluble in alcohol and readily dissolved
by alkaline solutions.
The inner bark is very mucilaginous, and contains a little
tannic acid which gives it a somewhat bitter and slightly astringent
taste, it also contains a great deal of starch.
Modern Uses: Tonic, demulcent, astringent
and diuretic. Wasformerly employed for the preparation of an antiscorbutic
decoction recommended in cutaneous diseases of a leprous character,
such as ringworm. It was applied both externally and internally.
Under the title of Ulmus the dried inner bark was official in the
British Pharmacopoeia of 1864 and 1867 directions for the preparation
of Decoc. Ulmi being as follows: Elm Bark 1 part, water 8
parts; boil for 10 minutes, strain, make up to 8 parts.
A homoeopathic tincture is made of the inner bark, and used as
an astringent.
Fluid extract, dose 2 to 4 oz. three or four times daily.
A medicinal tea was also formerly made from the flowers.
- In Persia, Italy and the south of France, galls, sometimes
the size of a fist, are frequently produced on the leaves. They
contain a clear water called eau d'orme, which is sweet
and viscid, and has been recommended to wash wounds, contusions
and sore eyes. Culpepper tells us:
- 'the water that is found in the bladders on the leaves of the
elm-tree is very effectual to cleanse the skin and make it fair.'
Towards autumn, these galls dry, the insects in them die and there
is found a residue in the form of a yellow or blackish balsam, called
beaume d'ormeau, which has been recommended for diseases
of the chest.
Other Names: Ulmi cortex. Broad-leaved
Elm. Ulmus suberosa (var. Orme).
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