|
By Thomas Wilkie, Forester,
Ardkinglas, Cairadow.
[Premium—Five Sovereigns.]
In reporting upon the
management of plantations, it is necessary to embrace wholly that system
practised by the reporter, and to state whether the chief object of his
management be ornamental or profitable forestry. Both these classes are,
and ever ought to be, adopted on all properties. A desire, however, seems
to exist at the present time to grow a crop of profitable wood upon ground
which is incapable to carry such a crop, but would, in many cases, carry a
few ornamental trees.
The subject of selection of
plants has been largely discussed, and many useful inquiries made thereon.
Some practical men have been successful in this department, while others
have failed, although acting upon the same principle as the former. The
climate, exposure, state, and class of soil, &c, are so varied that one
often finds himself quite baffled, while others tell of their success.
I find that the best guide
for the planter is to study nature, so far as is within our power, for
wherever we find trees growing naturally, we are sure if we plant the same
species on similar soils, temperature, and exposure, that we will be
successful. I quite believe that we are able to beautify many of our
barren-looking spots with plants, though some of them may be, and are,
quite incapable of producing what I may call a remunerative crop Many of
our mossy hags vary so much in depth and kind that it is difficult to
ascertain with perfect accuracy what class of plants is best adapted for
such soils. From a careful selection, however, if moderately well drained,
a sufficient number might grow to have an ornamental appearance. From
severe droughts, late or early frosts, more especially if on a low
elevation Liable to hoar-frost, the plants suffer, languish, and
ultimately die out, while on a higher elevation they might grow quite
well. Damp soils also are incapable of producing a profitable crop of
timber when the water is stagnant on the ground; but if merely percolating
it, there is no fear of many plants dying if they are judiciously
selected. Draining in a plantation ought always to be carried on to such
an extent as to prevent stagnation of the water, otherwise the water
becomes putrid and putrifies the natural sap of the plants, which I
believe to be the cause, combined with atmospheric influences, of
generating those insects which attack the roots and fibres of the plants.
For high elevations, where hard gravelly till abounds, a careful selection
of plants ought to be made. In such cases I would strongly recommend the
hazel and birch to be plentifully distributed among conifers, embracing
the larch and Scotch fir, as they are almost certain to grow, and would
prove an excellent shelter, while acting as nurses for the conifers. These
classes of plants, along with the mountain pine,—Pinus pumilio synmontana,
- should form a good proportion in plantations upon high bare, or
projecting rocks, to which it would be well to add the mountain ash or
rowan tree. These, mixed with a few larches in the richer hollows, would
present a beautiful aspect during the summer season, and the above ground
is only capable of being made ornamental.
The drains in the
plantation ought to be inspected periodically, and if any places are found
where the water is stagnant, it ought to be carried off either by
deepening the existing drains or forming new ones.
Thinning ought to commence
as soon as the branches begin to meet, and the principle on which it ought
to be conducted ever should be, not to allow the trees to touch one
another.
The margins of plantations,
roadsides, the edges of drains, as well as high projections, should be
well thinned out at first thinnings, so as to allow those left to get well
established in the ground. As soon as thinning operations are completed
for the time being, the drains ought to be examined to see if any branches
have been left in them, if so, to get them cleared out. The hardwood trees
ought to be looked at, and if necessary to foreshorten the heavy branches,
and to cut off or foreshorten all double or treble tops, leaving the one
most closely connected with the main stem. In some cases I adopted close
cutting off, in others I preferred to cut only half-way down the double
top. If the main leader is well branched I adopt the former, and if badly
branched, the latter process. I prefer cutting off any double tops of the
conifers, of whatever kind, during the month of September, as they do not
then bleed. No age can be stated at which thinning of plantations ought to
commence, neither when it should be done periodically, as some parts may
require to be twice thinned before other parts require it at all. I find
the principle of not allowing the trees to touch my safest guide in this
matter. It is an object, however, I always adopt, so far as practicable,
to carry up as many plants as the ground will bear till twenty-five or
thirty years of age, as I find the wood about that time very saleable,
being well adapted for pitwood. Previous to thinning a plantation, say
between the ages of twelve and forty years, I go over it a year preceding,
and after selecting I prune all my standards which I intend to leave,
acting upon the principle of balancing the trees as fairly as possible;
foreshorten all heavy branches, as well as those likely to be broken off
by the wind, and cutting off all superfluous and dead branches at the
smallest part or neck of the branch, afterwards dressing with the pruning
knife.
A great deal of damage is
often done to standing trees by dragging, which I think might be easily
avoided, as I find by attending to the following rule that I get scarcely
any damage done:—I cut places at the roadsides for a centre to drag to for
cross-cutting and loading the carts at; I then fell all the trees at an
angle of not more than 35 degrees either up or down hill from the drag
roads, which run straight up and down hill. These roads, as well as the
drains, after the dragging has been completed, should be attended to, as
they naturally gather water in their courses and carry it into the
hollows, which seriously affects standing trees. The water ought to be
carried off to the nearest drains. Another system I always study in
thinning is, when two trees are allowed to grow closely together rather
too long, as they sometimes are, I cut out, if on a westerly exposure, the
one on the east side, as the other is more likely to resist the wind from
the west; if on an easterly exposure, the opposite, and other exposures
similarly. Though all these rules are duly attended to we cannot get every
tree to grow to like proportions, in fact, one forester plants, but seldom
has charge of his plantations till they become of much value, as one man
sows plants and trains, and another cuts, down at his pleasure. However,
the rule for one and all is to leave that class for a permanent crop that
is showing the most vigour in growth, which can easily be seen. If that is
the case, as it ever ought to be, of the forester, he will act wisely. No
demand and no pecuniary objects ever ought to sway him from this rule,
excepting in a case of necessity for the property use.
As a general rule, thinning
operations ought to be finished in a plantation by the time it reaches say
forty-five to fifty years of age, and have the standards only left, none
of which ought to be cut out unless showing symptoms of decay, or in case
of necessity as above.
The plantation, the
management of which is about to be described, is 205 acres in extent;
altitude, 650 feet above sea-level. Exposure on north side to the sea a
mile distant, on east. side being rather sheltered by a ridge running from
top of hill near to north-east corner, south side open, and the west side
somewhat sheltered by a higher hill further west. Soils various, chiefly
mossy loam, with subsoil of porous gravel on the lower portion. In flats
behind rocks of greyish whinstone, which abound on hill-side, and in some
cases are prominent, the soils are mossy loam and virgin soil, subsoil
being of a porous, sandy nature.
The hill is somewhat
conical in shape, with flat on top of black peat, varying in depth from 9
inches to 2½ feet.
The plants were Scotch fir,
larch, spruce, and silver firs, oak, elm, and ash, and were distributed 4
feet apart, as follows:—
The Scotch fir, larch, and
spruce covered the top and down the sides all round to a distance of 150
yards. On the north side were planted Scotch fir, larch, spruce, and
silver firs, with a few oak, elm, and ash, more of the Scotch fir, larch,
elm, and ash than of the other plants; on the east side were the Scotch
fir, larch, spruce, and ash only; on the south side larch, oak, spruce,
and silver firs; on the west side a mixture of all the above-named plants.
Age at first thinning, eight years.
Measurement of Scotch firs
on tops being 4½ feet in height and 4½ inches in girth at a foot from
ground. Larch and spruce 5½ feet in height and 5 inches in girth. On the
hill-sides all round, the average of Scotch fir being 6 feet in height and
5½ inches in girth; larch and silver firs, 7 feet in height and 6 inches
in girth ; spruce, 6 feet in height and 5½ inches in girth. The oak, elm,
and ash averaged in height 5½ feet, and in girth 4½ inches. The probable
expense of plants, planting, and keeping of same from time of planting to
this date might be stated at £2100.
At this age (eight years) I
observed that the larch and silver firs, together with the ash and elm, on
north side showed signs of most rapid growth; on the east side the larch,
elm, and ash ; on the south and west sides larch, silver firs, and oak. On
the lower section the plants were touching each other. I therefore
commenced thinning operations, endeavouring to relieve those showing signs
of most rapid growth, studying always to take out those post drawn up and
void of branches, strictly adhering to this rule on the north side, it
being exposed to the sea. The plants higher up the hill having still
plenty of room, I resolved not to touch them till three years later. After
the thinning operation was completed I went over the whole plantation,
relieving the main leaders, and foreshortening all heavy lateral branches
of the hardwoods, acting upon the principle already advanced. The
thinnings of the larger larch trees were used for protecting trees which
had been planted singly, and repairing fences round cottagers' gardens,
&c, the remainder being granted to tenants and cottagers on the
understanding that they carried them out of the plantation, stem and
branches entire without pruning.
Three years later I found
fir trees on lower section to gain 3 feet 6inches in height, hardwoods 2½
feet and girth in proportion; on higher sections and hollows on top had
grown 2½ feet, and increased in girth 2½ inches. They required to be
thinned, and I did so, acting upon the principles already adverted to. The
thinnings were disposed of by converting the larch into stabs for repair
of fences and sheep net stakes, and the hard-wood's for fuel wood, which
cost and realised as on table annexed. The remainder were granted, as in
former case, to cottagers, &c.
At sixteen years of age the
conifers on an average were 16 feet in height and 14½ inches in girth,
hardwoods 13 feet in height and 9½ inches in girth. I selected, pruned,
and foreshortened all standard hardwood trees. I again thinned out on
former principles, leaving upon the high tops Scotch firs mostly, as most
likely to resist the exposure, and upon projecting rocks and ridges the
oak and Scotch fir, still studying to leave those trees maintaining the
healthiest appearance and showing signs of most rapid growth. As thinning
was proceeded with I made pollards of a sufficient number of hardwoods
nearest to the margin of the plantation, with the intention to transplant
them the following year into the line of fence to act as stabs. The
thinnings of a few of the larches were used as stabs until the pollards
got established in soil, and the remainder disposed of by sale to a wood
merchant. The cost and realisation of this thinning is also shown in table
annexed.
At twenty-two years of age
I found the conifers avenged 23½ feet in height and 20 inches in girth,
the hardwoods 19 feet and 15½ inches. A good many trees on the higher
portion being unsuitable for pitwood. At this time I only took out those
trees actually necessary with a view to allow the others to grow to a
sufficient size for pitwood; because if there are many! trees that will
not measure 3 inches diameter at 15 feet in length, the value is
considerably reduced. Those suitable for pitwood were sold, and the
smaller trees were used for estate purposes.
At twenty-six years of age
I found the conifers 28 1/6 feet in height and 23½ inches in girth, the
hardwoods 23 feet in height and 20 inches in girth. Having the previous
year gone over the plantation and foreshortened all heavy branches and
double tops, knowing by experience and from observation that hardwoods
about this age are apt to become hidebound when severely thinned or
pruned; because when they are severely thinned they are left more exposed
to the atmosphere, and when pruned too much they are deprived of part of
their respirative organs, both these causes having a tendency to produce
young shoots from the bole of the tree, so that instead of reaping a
benefit from either, they are retarded in their growth. I commenced
thinning at the margin of the wood, acting upon the principles adverted
to, viz., of not allowing the trees to touch; but on coming to the tops of
projecting rocks and high ridges to prevent the conifers being too much
drawn up, I endeavoured to select the best branched ones to stand, because
if allowed to get overmuch drawn up they are apt to be blown down. I found
the Scotch fir and oak on these ridges growing well, and gave them plenty
of room for the above reason.
The elm and ash on the
lower portion, both on north and east sides, as well as the larch,
surpassed the others in growth.
These I endeavoured to
relieve. The oak, silver firs, and larch on the better soils were doing
well. The oak particularly so on the southern exposure, it being partial
to the sunny side, unless openly exposed to the sea. The thinnings were
cut, pruned, and dragged by men and horses on the estate during the autumn
and winter, excepting the oak, which were allowed to stand in order that
they might be peeled during the summer. The whole was sold the March
following, the drains being scoured out, as well as the water cut off the
drag roads.
A heavy gale having
occurred in the autumn, I went carefully over the plantation to see what
damage had been done, and found only twenty trees blown down, and scarcely
a branch of the hardwoods broken. The oaks and conifers on the high ridges
having afforded a perfect protection on either side.
At thirty years of age I
found conifers 33½ feet in height and 30 inches in girth, and the
hardwoods 28 feet in height and 24 inches in girth. I went over the
plantation, thinning out those trees beginning to press upon the
hardwoods, these being cut, lopped, and dragged as formerly. The hardwoods
were used for estate purposes, and the conifers sold. I went over the
drains and drag roads, giving them the necessary repair.
At forty-five years of age
the conifers were 48½ feet in height and 43 inches in girth, the hardwoods
43 feet in height and 38 inches in girth. Believing it to be full time
that the standards only should be left in the wood, I cut down all
excepting them, leaving on an average seventy trees per acre. The
thinnings were cut, lopped, and dragged as formerly during the autumn and
winter seasons, and sold. The heavy-branched hardwoods were lightened, and
the drains and drag roads were carefully gone over as on former occasions.
In the March following
rather a severe gale occurred, but no trees were blown down, and scarcely
a branch of the hardwoods were broken.
I attribute the cause of so
few trees having been blown down to the early as well as the more remote
thinnings of the plantation on the margin, roadsides, drainsides, tops of
projecting rocks, high ridges, and thin soils, the hardwoods having been
early and frequently pruned, as was found necessary, and conifers on
projecting rocks having established themselves in the soil, presenting
rather a bushy appearance, and serving as an excellent shelter to the main
body of the plantation.
The tables are based on the
average prices obtained in the midland counties of Scotland. It will be
understood that there were a sufficient number of roads made before the
ground was planted. The return from woods is considerably increased by
having a sufficient number of roads in plantations, and the expense of
dragging was very much reduced by having the woodmen to carry the felled
trees to the drag roads. I believe that in thinning operations a further
saving would be effected by hoseing or ringing the trees a year prior to
felling, as by that method the wood would be seasoned and fit for
immediate use, and reduce its weight, if conifers, by two-fifths. It would
also retard the propagation of insect life, seeing that the natural sap
would be drained out of the bole and branches of the trees, the reporter
believing that the sap in the green branches, after being lopped off the
tree and allowed to lie upon the ground, become putrefied, and develops
insect life.
Sales of wood ought to be
made in as large quantities as possible, particularly when of a size
requiring to be sawn up, and offered at a time when the market is not over
glutted. Every facility should be given to the purchaser for the
manufacture of the wood on the ground, as the reporter believes foresters
cannot profitably compete with the wood merchant in the manufacture of
timber.
It may be useful to remark
that the pollards introduced into the line of fence have proved an
excellent fence, and one of the most impregnable the reporter has ever
seen, far surpassing in strength and durability for plantation,
enclosures, or divisional fences in fields, the wire fences erected upon
iron standards and batted in with sulphur, commonly in use. The use of
sulphur in batting in of standards in iron fences was suspected by me
years ago to be deleterious to iron. This has been tested and proved by an
eminent and practical analytical chemist. The iron standards, of a size
commonly in use are corroded to such an extent as to render them useless
in the course of sixteen or twenty years when deeply bedded in damp soil,
and I would recommend the use of lead instead. I am experimenting on the
adaptability of pitch and sand, hoping to introduce a cheaper method. |
