The Oak is the largest and longest-lived of our
native trees and a very familiar object in the
landscape in most parts of the British Isles.
The sturdy, massive trunk, the broad, rounded
outline of its head, its wide-spreading lower
limbs, the wavy form of its leaves, and the egg-and-cup-shaped
fruit, are characters that cannot be confused
with any other tree.
The human centenarian is regarded with reverence,
although he may have nothing beyond his great
age to commend him; but we think of the long period
of history of which he has been a spectator, possible
an active maker of history. The huge Oak has probably
lived through several such periods. Compared with
the Oak, man is but of mushroom growth. It does
not produce an acorn until sixty or seventy years
old, and even then it is not mature. Not till
a century and a half have passed over its head
is its timber fit for use, and as a rule it is
not felled under the age of two hundred years.
Many oaks are left to a much greater age, or we
should not have still with us so many venerable
specimens, and where they have not been left until
partially decayed, the timber is found to be still
very valuable when finally cut down.
One of these patriarchs of the forest, known as
the Gelenos Oak, and stood about four miles from
Newport, Monmouthshire, cut down in 1810, yielded
2,426 cubic feet of sound timber and six tons
of bark. The timber and bark from this one tree
were about equal to the average produce of three
acres of oak coppice after fifteen years’
The Oak is most abundant on clay soils, but is
at its best when growing in deep sandy loam, where
there is also plenty of humus. Its roots, in such
soil, strike down to a depth of about five feet.
Full-grown, it varies in height from sixty to
one hundred and thirty feet, and difference depending
upon situation; the tallest being those that have
been drawn up in forests, at the expense of their
branches. Trees growing freely in the open are
of less height, and are made to appear comparative
dwarfs by the huge proportions of the bole. In
the forest this may be up to ten feet in girth,
but in isolated specimens, may be as much as thirty-six
The thick, rough bark is deeply furrowed in a
large network pattern, which affords temporary
hiding-places for many kinds of insects. The Oak
is more persistently attacked by insects than
any other tree, and one authority has tabulated
about five hundred that get their living, mainly
or entirely, from their attacks on the foliage,
bark, or timber. With some species this warfare
is waged so extensively that in some years, by
early summer, the trees are almost divested of
their foliage, and a new crop of leaves becomes
a necessity. But the reserve forces of the Oak
are quite equal to this drain, and the tree does
not appear to suffer.
The Oak flowers in April or May and the blossoms
are of two distinct forms – male and female.
The males are borne at intervals along a hanging
stalk, two or three inches in length. They are
green and inconspicuous. The female flowers are
fewer, and will be found on short erect stalks
above the male catkins. Each female flower consists
of a calyx, invested by a number of overlapping
scales, and enclosing an ovary with three styles.
The ovary is divided into three cells, each containing
two seed-eggs. An acorn should therefore contain
six kernels, but, as a rule, only one of the seed-eggs
develops. The overlapping scales at the base of
the female flower become the rough cup that holds
Under the name “Common Oak” two distinct
species, Quercus Robur and Q. petraea are included.
The former is most abundant in the south of England
occurring as a native tree in the deeper, heavier
soils. Q. petraea is common in the west and north
on shallower and sandier soils. Q. Robur may easily
be distinguished by the presence of two lobes
at the base of each leaf and by the absence of
the minute star-shaped hairs which characterise
the under surface of the leaves of Q. petraea.
The stalks of the leaves and acorns vary considerably
in length in both species. Also, the fact that
hybrids between the two are of widespread occurrence
has led to considerable confusion in identification
and to the view that there is only one variable
species of Oak in Britain.
Several Oaks of foreign origin are also grown
in our parks and open spaces; among then the Holm
Oak (Quercus Ilex) whose evergreen leaves have
toothed or plain edges, and occasionally the lower
ones developed holly-like marginal spines. It
has a much thinner, more even bark than out native
Oak, and of a black colour.
The Turkey Oak (Quercus Cerris) is a much larger
tree, attaining similar heights to our British
species, but more pyramidal in form and with thick,
greyish bark. The stalk less acorn-cups are covered
with mossy scales, and the whole tree is of straighter
growth, and the branches are not so gnarled and
twisted as Quercus Robur.