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Family Ulmaceae
Ulmus
There are four species of Elm commonly met with
in England. The Wych Elm (Ulmus glabra), the smooth-leaved
Elm (U. carpinfolia), the Plots’ Elm (U.
Platii) and the English Elm (U. procera). In addition
there is the Cornish Elm (Ulmus stricta) confines
to Devon and Cornwall, and hybrids such as the
Dutch Elm (Ulmus hollandica), and the Huntingdon
Elm (Ulmus vegeta). It has been accepted generally
that the English Elm had been introduced by the
Romans; but it proves to be unknown as a wild
tree except in England.
The Wych Elm is also known as Mountain Elm, Scots
Elm and Witch Hazel, under the Latin name montana.
Although the Wych Elm is found at an elevation
of 1,300 feet in Yorkshire, and the English Elm
at 1,500 feet in Derbyshire, they are distinctly
trees of the lowlands and valleys.
The Wych Elm forms a trunk of large size, from
eighty to one hundred and twenty feet or more
in height, with a girth of fifty feet, and covered
with rough bark. Its long slender branches spread
widely with a downward tendency, the downy twigs
bearing their leaves in a straight row along each
side.
The leaves are somewhat oval in general form,
but the two sides of the midrib are unequal in
size and shape. Their edges are toothed, and the
surfaces are rough and harsh to the touch. The
hairs that cover the strong ribs on the under
surface serve to protect the breathing pores from
the dust. On leaves of the pendulous form of this
tree when grown in city parks and gardens these
hairs will often be found to be quite black with
the soot particles gathered from the air. Trees
need carbon, but in a gross form they are often
suffocated by it.
The dark red flowers are produced in bunches,
in February or March, from the sides of the branches.
They are a quarter of an inch long, bell-shaped,
their edges cut into lobes, and finely fringed.
The ovary, with its two styles, is surrounded
by four or five stamens with purple anthers. They
appear before the leaf-buds have opened, and are
dependent on the wind for the transfer of pollen.
The fruit is an oblong samara, about an inch long.
This consists of a single seed in the centre,
invested by a thin envelope, which forms a light
membranous wing, which gives it buoyancy and enables
it to float through the air to a little distance.
These seeds are not produced until about the thirtieth
year of the tree’s life, and although they
are ripened almost annually thereafter, good crops
are biennial or triennial only.
The Wych Elm never or very rarely produces suckers.
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