the trees of great britain & ireland - Facsimile Books & other digitally ...

19 The Trees of Great Britain and Ireland
At Dartrey, in co. Monaghan, the Earl of Dartrey planted in 1882 a considerable
area of slightly hilly ground with a mixture of larch, spruce, Douglas fir, and
Thuya. In 1904, twenty-two years after planting, of the four species, all grown
densely under the same conditions, the Thuya had made the most timber, the trees
averaging 40 to 50 feet in height by 4^ feet in girth. The Douglas fir was slightly
taller, but not so stout in the stem, averaging about 3^ feet in girth. 'The Earl of
Dartrey speaks very highly of the timber of Thuya, which he considers to be
superior to that of the best larch.
At Brockley Park, Queen's Co., the residence of Mr. Wm. Young, there are
trees growing on light soil on limestone, which have made 40 cubic feet of timber in
30 years, and 50 feet in 35 years. The tallest tree, 30 years old, was in 1906
64 feet high by 7 feet 9 inches at a foot from the ground, and 3^ feet girth at 24 feet
up; and its branches were 105 feet in circumference.
TIMBER
Sargent says, Garden and Forest, iv. p. 109 : " The wood is very valuable; it
is light, soft, and easily worked, and so durable in contact with the ground, or when
exposed to the elements, that no one has ever known it long enough to see it decay."
The great value of the cedar for shingle-making has long been known, and
several instances were mentioned by reliable people in Vancouver Island of hand
made shingles, or " shakes" as they are called, remaining good 40 to 50 years
on roofs without decaying in the wet climate of this island.
They are now manufactured on a very large scale by machinery in all the
Puget Sound mills, and exported largely to the middle and eastern states in neat
bundles, and I have no doubt that, if carefully selected and laid, such shingles would
be very suitable for roofing in England. Sargent says, ' Garden and Forest, iv.
p. 242, "that nearly 100 mills were in 1891 exclusively devoted to making Red
Cedar shingles, and that the combined output of half of these operated by one
company was 3,500,000 per diem. They are now supplanting the Pine shingle of
Michigan, the Cypress shingle of the south, and the Redwood shingle of
California."
As a rule in the American forests, they begin to decay at the heart long before
they attain their full growth, and the trunk seems to continue growing round the
hollow centre for an almost indefinite time, as in the case of the yew. On drier
land it keeps sound longer, and if cut when 2 to 3 feet in diameter the wood is
probably at its best. It resists decay for an immense time when fallen.
For inside finish the wood is excellent, though not hard enough for flooring and
wainscot, or strong enough for joists. For ceiling and panelling it is most orna
mental when well cut, as I saw in the Hotel at Duncan's, Vancouver Island.
Mr. Stewart has found at Benmore that it is very suitable for all estate
purposes, and prefers it to larch for planking and fencing, as he finds it less liable to
warp and crack. (H. J. E.)
Thuya 191
THUYA OCCIDENTALS, WESTERN ARBOR VIT/E
Thuya ocddentalis, Linnaeus, Sp. PI. 1 002 (1753); Loudon, Arb. el Frut. Brit. iv. 2454 (1838);
Sargent, Silva N. America, x. 126, t. 532 (1896), and Manual Trees N. America, 7 4 (1905);
Masters, Card. Chron. xxi. 213, figs. 67, 68, and 258, fig. 86 (1897); Kent, in Veitch's Man.
Conif. 244 (1900).
Tliuya plicata, Hort. (nan Don).
A tree, attaining a height of 50 to 60 feet, with a stout and buttressed trunk, some
times 6 feet in diameter. It often divides near the base into two or three stems.
In England the branches, short and spreading, form a tree pyramidal in outline,
which is not so dense in foliage as Thuya plicata. Bark of the trunk scaling off in
thin papery rolls, but not so freely or so finely as in Thuya japonica. The branches
when of no great size begin to show scaly bark.
The branch systems are disposed in horizontal planes, resembling those of
Thuya plicata; but their main axes are flattened, being compressed from below
upwards, while the leaves are shorter than in that species, ending in similar long
points. The flat leaves on the main axes are studded with conspicuous large
circular elevated glands. The smaller leaves on the ultimate branchlets vary as
regards the presence or absence of glands; the lateral pairs are shorter than and not
so acutely pointed as in Thuya plicata. The foliage is dark green above, pale green
and not marked with white streaks below.
The male flowers, minute and globose, are composed of three decussate pairs of
stamens. The female flowers are yellow.
The cones become deflected when ripe, as in Thuya plicata. They are oblong,
light brown, and composed of 4 to 5 pairs of scales, of which the 2nd and 3rd pairs are
larger than the others, and fertile. The scales are ovate or spathulate, ending in a
rounded or acute apex, with a minute external process, which is generally much less
developed than is the case in Thuya plicata. The seeds, usually two on each fertile
scale, are scarcely distinguishable from those of the last-named species.
Seedling}—Cotyledons as in Thuya plicata. The caulicle and stem are quad
rangular. The first two true leaves are opposite, spreading, and similar to the
cotyledons, though smaller. These are followed by 5 or more whorls or pseudo-
whorls, each of three similar leaves, linear, acute, and sessile. The ultimate leaves
are opposite, decussate, and adnate for the greater part of their length to branchlets,
which are flattened from above downwards.
VARIETIES
Few trees, except Cupressiis Lawsoniana, show a greater tendency to varia
tion in the seed-bed. Sargent says that if anyone will sow a quantity of seed
he will be sure to find forms among the seedlings as novel and as interesting
1 See Lubbock, Seedlings, ii. 548, 560 (1892).