Albert Francis Blakeslee.

Trees in winter; their study, planting, care and identification online

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thus increased in thickness each year, but unlike the wood, it is
subjected to the pressure of growth from within and in most spe-
cies eventually dies, cracks and wears away on the outside as rap-
idly as it is renewed on its inner surface.

The annual rings usually give an accurate record of the age and
rapidity of growth of a tree, since defoliation by insect injury or
other influences that would cause a double period of growth in a
single year are of rare occurrence. Trees like the Oak and Ash
produce in the early part of the growing season large tubular cells
which extend vertically up and down the trunk and later form cells
of smaller dimensions. In such trees, therefore, the porous spring
wood can be readily distinguished from the denser summer ivood.

At the end of a log a cr-oss section of the trunk is exposed, and
on it can be seen fine lines radiating out from the center. These
are cut edges of the medullary rays or pith rays, as these narrow
sheets of tissue are sometimes called. A section cut lengthwise of
the log and parallel to the annual rings is called a tangential sec-
tion and shows the extent up and down of the medullary rays as
seen in end view. The radial section is made lengthwise of the
log and parallel to the medullary rays. If extended, it would pass
through the center of the tree. This is the direction in which
lumber is sawed in making "quartered oak." The shiny streaks
■ ^ Oak wood cut in this fashion are called the "silver" and are in



44 TREES IN WINTER

fact medullary rays seen in surface view. In the radial section
the annual rings are evident and the spring wood is seen to be made
up of hollow tubes. In the tangential section the rings^, if they
show at all, form Vs or ellipses due to the saw failing to cut ex-
actly parallel to the grain. Boards are generally sawed off from
parallel sides of a log so that, although the outer cut is tangential
and the median cut is radial most of the boards will be sections
intermediate between these two. The markings on the finished
lumber will accordingly vary in appearance.

To many it is a surprise to learn that the large bulk of a tree
is dead, literally with no more life than the proverbial barn door.
Hollow trees are not infrequently found alive and flourishing.
Except for their liability to be blown over, they often do not seem to
be greatly handicapped by the loss of inner.wood. The older wood,
therefore, is mainly of service as a mechanical means of support
and has no part in the life activities of the tree. In some fonns
the inner wood as it dies, takes on a darker color and under the
name of heartwood is easily distinguished from the younger,
lighter colored sapwood toward the outside. The outer layers of
the bark also are dead. There remains, therefore, as the essential
living portion of the stem, the cambium layer with the inner bark
on its outer side, and the sapwood just within.

Experiments have shown that the ascending currents which
carry water and» dissolved minerals up to the leaves are located in
the sapwood. The inner bark transports the manufactured food
from the leaves. If the inner bark is severed, as by "ringing,"
the descending sap is interrupted and the roots ultimately
will die of starvation. Portions above the ring are still able to
obtain water and raw material through the channels in the sap-
wood so that injury brought about by girdling may not make itself
shown till the succeeding season.

The cambium layer is responsible not only for the regular for-
mation of wood and bark but also for their regeneration. An in-
jury which exposes the cambium will excite this layer to increased
growth and a formation of wound tissue or callus will result.
Callus spreads gradually in all directions from the exposed cam-
bium where it first makes its appearance. Bark forms on its outer
surface as it slowly seals over the wound. Unless destructive
wood fungi gain entrance through the wound, the healing pro-



PLANTING AND OARE OF TREES 45

cess may be completed without injury to the tree. Scars, more or
less entirely covered by callus, are familiar objects on trees that
have been pruned. They are shown in figures 44 and 47. The pro-
cess of grafting depends upon the growing together of this wound
tissue found on two different twigs when their cambium layers are
held in contact.

Reproductiofi — A tree is a flowering plant. Except for
a few forms like our fruit trees, Magnolias, Horse-chestnut, Catalpa,
Locust and Tulip Tree the flowers are generally inconspicuous
and consequently often overlooked. From perfect flowers come
seed, and seeds are the natural means of reproduction in flowering
plants. Most species have both sexes upon the same individual,
with male and female organs in the same flower, or in separate
blossoms on the same tree. The Willows, Poplars, and Ashes,
however, have the different sexes on separate individuals, and are
called, therefore, dioecious. A single tree of a dioecious species
will bear flowers of only a single sex. Cuttings carry the sex of
the tree from which they were made. Forms like the Lombardy
Poplar which produce only male flowers never set seed and can be
multiplied, therefore, only by nonsexual methods such as by
cuttings.

Trees do not bear with equal abundance every year. Thus, al-
though a few cones may be produced each season, the White Pine
in the northeastern states has a good seed year but once in about
six years. Eeproduction in relation to propagation is further dis-
cussed in the following chapter.



46 TREES IN WINTER

CHAPTEE II
THE PROPAGATION OF TREES.

PROPAGATION FROM SEEDS.

Nature's Way — The natural way for trees to reproduce
their kind is by seeds. The trees in the virgin forest
have been produced from seeds and without the aid of man. The
moist iloor of the forest offers favorable conditions for the germi-
nation of seed and the growth of the seedlings. There is not
room for the development of all the trees that commence growths
Only the strongest and most favorably situated individuals survive
and the less fortunate ones are overshadowed and are lost in the
struggle.

Since there is room in the forest for the development of only
a limited number of trees, nature has adopted wonderful methods
for the desemination of seeds far beyond the limits of the forest.
Some specimens that commonly grow along streams make use of
the water to carry their seeds to distant places down stream. This
probably accounts for the rows of Carolina Poplars and Sycamores
along certain river banks and on areas that are usually flooded in
the spring. The seeds of many other species are scattered by
animals. Is it not probable that the Hickories and other nut trees
commonly found growing along stone walls have come from the
nuts accidentally dropped by squirrels on their way to their nest-
ing places? Birds are often responsible for the desemination of
fleshy or berry-like seeds of such species as the Mulberry, Hack-
berry, Sassafras, Dogwood, Mountain Ash, Hawthorn, Shadbush,
Holly, Juniper, Cedar and the Cherries.

The most common agency for the desemination of seeds is the
wind. The seeds of many species are equipped with peculiar de-
vices by which they may be carried various distances from the
parent trees. The Hop Hornbeam seeds carry balloons (see p. 277)
and the Sycamore seeds parachutes. The seeds of the Catalpa fly
in a monoplane (see p. 429) and those of the Elm and Ailanthus
sail through the air on flimsy rafts, (see p. 391). The seeds of the
Birches are constructed in the form of tiny birds (see p. 287), while
those of the Maples (see p. 403) are supplied with wings resem-



PLANTING AND CARE OF TREES 47

bling those of certain insects. The Ashes have dart-like seeds that
shoot through the air in great profusion (see p. 423), and the Bass-
wood seeds (see p. 417), are suspended from a leafy shield by means
of which they are carried long distances.

While nature's method of seeding is truly unique, it is also
remarkably extravagant. A very small percentage of the seeds
that are formed ever germinate and develop into trees. Many of
them after falling to the ground are destroyed by forest fires.
A large nimiber are eaten by insects and other animals. Many
more fail to find suitable locations for their germination and
growth. To allow for this great waste and to keep up
the supply of the various species, tree seeds are bourn in
great profusion. It is interesting- to estimate the number of seeds
bourn by a single tree of the more prolific species like the
Mulberry, the Catalpa, the Sycamore, the Poplars, the Birches, and
some of the Evergreens.

It may be plainly seen that in the economic production of tim-
ber, natural seeding is not to be depended upon. Although in
the hands of an expert forester the natural seeding of cleared land
from adjacent forests, may often produce satisfactory results.
Direct planting with nursery-grown trees is likely to give quicker
and more certain results and furnish only the desired kinds of
timber.

The Forest Nursery — While it is possible to obtain
seedlings for forest planting at a reasonable price, there is no rea-
son why the farmer or forest planter cannot grow his own trees
from seed. To encourage the planting of forest trees some states
are furnishing young trees at prices but slightly in excess of the
cost of production. Even at these low rates the planter would find
it more satisfactory to grow his own trees. To do this successfully
he needs to know only a few general principles. The method em-
ployed in the growing of some species may differ slightly from that
used in others, but the principles are very much the same with all.
The work now is largely in the hands of specialists, but when farm-
ers and others come to realize the ease with which trees may be
grown and to appreciate the saving in money, there will be more
planting done.

Collectfng Seeds for Planting — On accoimt of the drffi-^
culty of collecting and the exacting requirements in the



48 TREES IN WINTER

handling and storing of tree seeds^ the price usually is very high.
According to the reports of the United States Bureau of Forestry,
a pound of Larch seed costs from $12.00 to $16.00, White Pine
from $1.50 to $3.00, Sugar Maple .75c to $1.00, and White Oak
from 10c. to 25c. The forest planter, therefore, would do well
to collect his own seed and thus obviate this unnecessary expense.

In the collecting of seeds it is usually necessary to climb the
trees. The seeds are either picked by hand or are shaken or beaten
off and collected in large sheets on the ground. The practice of
cutting down trees for the purpose of obtaining their seed should
be discouraged. Some species, like the Chestnut, the Beech, the
Hickories, the Oaks, the Walnuts, and the Butternut, are more
easily gathered after severe frosts. The work of gathering seed,
however, extends from April to November, according to the spe-
cies. The season for some species, like the Birches, the Maples,
the Elms, the Poplars and the Willows, is very short, while that for
others, like the Common and Honey Locusts, the Catalpa, the Box
Elder, the Kentucky Coffee Tree, the Sycamore, and the Ashes,
is more extended and may stretch far into the winter. It is diffi-
cult to state definitely the exact time when seeds of the various
species should be collected. Of course they should not be gath-
ered until they are ripe, and to avoid loss it is usually advisable
to collect them as promptly as possible after they reach this con-
dition. Some species must be gathered promptly after reaching
maturity if they are to be saved at all. Others if left either on the
tree or on the ground are likely to be carried away by squirrels.

Storing Seeds — As a rule, seeds that mature before mid-summer
should be sown when gathered. Those that mature later
than August first should be stored until spring. Large seeds like
the nuts and acorns may be stored in earth outside or in a cold
cellar. The smaller seeds, except those of Evergreens, may be
stored in boxes in thin layers between layers of sand. The boxes
should be buried outside in the ground or placed in a cold cellar.
The seed of Evergreens requires a cool, dry place and is usually
placed in sacks and hung in cold sheds or barns. Some seeds need
to be subjected to frost before they will germinate and develop
properly. Others require two or more years contact with the
soil before they will germinate. These cases aie exceptions.



PLANTING AND CARE OF TREES 49

however, and are mentioned here to show that all kinds of seed
cannot be treated in exactly the same manner.

Some seeds require special treatment before storing for the
winter. During the early fall most kinds should be spread out in
thin layers in some cool, airy place, such as under a shed on the
north side of other buildings or on the upper shelves of a cool, dry
cellar. Nuts and acorns are best kept on the ground in a cool
shed. Most kinds require close attention to keep them from
heating and moulding. If the layers are too deep the seed is
likely to mould, and if too shallow it is likely to dry out. The
more succulent seeds should be in thinner layers than the dryer
kinds. With some of the quickly drying sorts it is sometimes nec-
essary to cover them with straw, chaff, or a thin cloth. Some
of the Evergreen cones require excessive drying before they will
open and release their seeds. The fleshy fruits of the Mulberry,
the Cherry, the Hawthorn, and the Plum, require macerating in
water until the seeds can be sep'arated readily from the pulp. The
shucks of Black Walnuts, Butternuts and Hickory nuts should be
removed within a few days after gathering. The most import-
ant point to be observed in the storing of seeds of any kind is to keep
them in a cool, dry place to prevent germination and at the same
time avoid excessive drying.

Testing the Vitality of Seeds — Some seeds will remain
viable for many years while others must be planted within
a few weeks to insure a good growth. Seedsmen frequentlv mix
their "left-over" seed with their fresh stock and this sometimes
accounts for the low degree of germination of some samples. It is
well, therefore, to test a sample of seed before buying large quan-
tities. The only strictly reliable test to determine the vitality of
seeds is germination, but this often requires many days or weeks
for results. With a little experience in examining fresh and stale
seed, one may expect to determine fairly accurately whether a given
sample will grow. The examination consists in cutting open about
fifty seeds of a sample and in observing whether the kernels are de-
cayed, moldy, abnormally shrunken or completely dried out. If a
large percentage of those examined are firm, plump, and normally
moist, the sample probably may be relied upon. The seeds of some
species, like the Ashes and Locusts, may be extremely dry and yet
be reliable.



uU TREES IN WINTER

The seed of a large proportion of the species will germinate
within ten to thirty days and the vitality of these may be definitely
determined by germination tests. A definite number of seeds of
any sample may be covered with sand or moss at a depth equivalent
to the diameter of the seed. The box containing the sample un-
der test should be kept in a place where the temperature ranges
from 60 degrees to 70 degrees F., and the soil or moss kept in a
moist condition. For the smaller seeds the use of sand will give
the best results and for the larger kinds either moss alone or a mix-
ture of moss and sand is recommended.

Planting Seeds — Seed beds should be located on moder-
ately light, well-drained soil. Whenever possible, it is also wxll
to locate the bed on the north or east side of a building, forest, or
other windbreak. A common and convenient width for seed beds
is four feet. The length may be extended according to the
amount of seed to be planted. The rows run crosswise of the bed.
In very large plantations it is usually advisable to sow the seed
in long rows or drills clear across the field, in much the same way
that vegetable seed is planted. This arrangement admits of horse
cultivation and lessens the hand work.

The soil should be well prepared by previous cultivation. Its
physical and chemical condition may be greatly improved by tne
addition of well rotted stable manure. Ground that has been un-
der cultivation for at least one year is not so likely to be infested
with injurious insects and will give better results than newly broken
land.

The best time for planting most species is early spring. Some
species, like Red and Silver Maple, River Birch, Elms, Poplars and
Willows, mature their seeds in June and these must be planted
immediately, but most species are carried over winter and planted
as soon as the soil can be properly worked. If the soil is too wet
the seeds are likely to rot, while if it is too dry the seeds will not
germinate until late in the season and may possibly remain in the
ground until the following season.

The seed of the species that make a small growth during the
first season, like Conifers, Birches, Elms, and Sugar Maple, may
be planted in rows about eight or twelve inches apart. It is some-
times sown broadcast in well prepared seed-beds and the seedlings
transplanted in nursery rows the first or second year following. The



PLANTING AND CARE OF TREES 51

seed of the rapid-growing species, like the Soft Maples, Hickories,
Oaks, Black Walnut, Butternut, Ashes, Elms, Locusts and Catalpas,
should be given more room and should be planted in rows two to
three feet apart. The seeds should be so spaced in the row that
the seedlings will not require thinning. Medium sized seeds and
those that have tested high in germination may be planted from
one to two inches apart, while the smaller ones and those that have
proven to be low in vitality should be spaced somewhat closer. The
larger seeds like nuts and acorns may be spaced about three inches
apart. For very small seeds it is customary to use a board on
which to stand and thus avoid trampling the soil. The rows in
which the seed is to be planted may be marked off by running a hoe
handle along the edge of the board.

The amount of covering that should be given seeds depends upon
their size and upon the character of soil. Large seeds should be
planted deeper than smaller kinds. A common rule is to cover all
seeds about three or four times their own depth. On light soil, and
especially during dry weather, they should be covered more deeply,
while on heavy soil twice their own depth would be sufficient. In
order to bring the soil moisture up to the level of the seeds and to
prevent the seed from being washed out by rain it is well to roll the
ground or firm it by walking on a board placed along the row.
The loss of moisture and the baking of the surface may be pre-
vented by scattering chaff on the seed bed after planting.

Care of Seedlings — The young seedlings of most species
will require shade for the first season and of the conifers for
the first two seasons. The necessary shade may sometimes be
supplied by the use of evergreen boughs, but the common practice
is to use frames made of lath. (See hg. 28.) The latter are placed
about their own width apart and nailed on end strips about two
inches in thickness and five to six feet in length. The frames are
supported eighteen inches above ground for conifers, and from two
to three feet for other seedlings. The screens are removed only
on cloudy days and during gentle rains. When the soil is suffi-
ciently moist the frames serve a useful purpose by shedding part
of the water that falls. With broad leaved seedlings it is usually
unnecessary to keep the shades on after the first of August.

When it is necessary to water seedlings the water should be
applied gently, allowing it to soak in. When good cultivation is



52



TREES IN WINTER



supplied it is seldom necessary to apply water. The cultivation
should be so frequent and thorough that no weeds will develop and
that a loose soil mulch will be maintained on the surface.

Transplanting — Most trees are large enough to be taken
from the seed bed after one year's growth. Conifers and a few
other species make a very slow growth and should be left in the
seed bed for tw^o years. The seedlings of some of the most rapid-
growing species are occasionally planted in their permanent loca-
tions at the end of the first season, but the usual practice is to trans-
plant them in the nursery for at least one season. The transplant-




Fig. 23. A one-year-old Cedar cutting.



ing is usually done in the spring, from the first of April till the
middle of May. The length of time that they remain in the nur-
sery depends upon the growth and this is largely influenced by the



PLANTING AND CARE OF TREES 53

character of the soil and the kind of treatment. In the moving of
young trees from one position to another^ great care should be
exercised in preventing the roots from drying out. This precaution
is especially necessary in the handling of conifers.

PROPAGATION BY CUTTINGS

It is a common thing to find willow twigs that have fallen from
trees and taken root. The branches of some species of willow are
so brittle that they are broken off by the wind. Some of these fall
in the water and are carried down stream for many miles and are
finally washed ashore^, where they find conditions favorable for
rooting.

From nature, therefore, man has learned that trees may be
propagated by cuttings. Most woody plants when given proper
conditions may be propagated in this way. Species differ greatly
in respect to their amenability to this method of propagation.
Poplars and Willows are very easily propagated from cuttings, and
the desired result often may be attained more readily by this means
than by the collecting and planting of seed. Some species, on
the other hand, are quite difficult to propagate in this way, and with
such the practice is to grow them from seed. The chief advan-
tage in propagation by cuttings is the saving of time. Many trees
started from cuttings are large enough at the end of the second
or third season for planting in their pennanent positions on lawns
or along roadsides. Furthermore, there are many horticultural va-
rieties, like the wee23ing forms, that do not come true from seed
and these must be propagated either from cuttings or grafted on
seedlings of the same or some closely-related species.

Mahing Cuttings — Cuttings from woody plants are usually
gathered in the late fall or early winter. There are three distinct
kinds employed in the propagation of trees, namely: simple, heel,
and mallet. (See fig. 24).

The simple cutting is employed generally with such trees as the
Willow and Poplar. It consists of a straight portion of a shoot
from six to twelve inches in length, nearly uniform in size
throughout, and containing tw^o or more buds. At the lower end
it is usually cut off just below a bud, because roots develop more
readily at the joints. Some species, like the Apple, Pear, Plum,
Cherry, Hawthorn, Mountain Ash, Elm and Ailanthus, are more



54



TREES IN WINTER



easily propagated from root cuttings than from cuttings taken
from above ground. These are also of a simple type and are
obtained from young trees that have been grown from seeds. The




Fig. 24. Hard wood cutting-s. A simple cutting- on the left; a heal
cutting in the center and a mallet cutting- on the right.



root from one of these trees may often be divided into from three
to twelve pieces.

Heel cuttings are made by severing twigs close to their bases and
in such a manner as to carry with them portions of the parent
branchy forming the so-called heel. Heel cuttings are usually
not more than six inches in length and are frequently used for
the propagation of spruces and firs.

Mallet cuttings are made by severing the parent branch
above and below a short side-branch so as to leave a mallet-like
piece of the former at the base of the latter. They are usually
from five to eight inches in length and are commonly used in the
propagation of Junipers and Arbor Vitaes.

Setting Cuttings — The various kinds of cuttings are handled
in much the same way. After being cut they are usually
tied in bundles of fifty, or more, with all the tops pointing in the
same direction. The bundles are packed in sand or soil and



PLANTING AND CARE OF TREES. 55

either buried on the north side of a building or stored in a cool
cellar until spring, when they are ready for planting. During the
winter the lower ends of the cuttings should become callused.



Online LibraryAlbert Francis BlakesleeTrees in winter; their study, planting, care and identification → online text (page 4 of 31)