Pollination 286-298
General Requirements 287
Methods 291
Crossing of Flowerless Plants 297
[Illustration]
NURSERY.--_An establishment for the rearing of plants. In America the
word is commonly used in connection with the propagation of woody
plants only, as fruit-trees and ornamental trees and shrubs. This is
erroneous. The word properly includes the propagation of all plants by
whatever means, and in this sense it is used in this book._
Tabular Statement of the Ways in which Plants are Propagated.
_A._ By Seeds.--_Seedage._
{ { { Root-tips.
{ { { Runners.
{ { 1. By { Layers proper:
{ { undetached { Simple.
{ { parts.-- { Serpentine.
{ { _Layerage._ { Mound.
{ { { Pot or Chinese.
{ {
{ I. On their { { 1. By undivided parts.--
{ own roots. { { _Separation_ (Bulbs, corms,
{ { { bulbels, bulblets,
{ { { bulb-scales, tubers, etc).
{ { {
{ { 2. By detached { { Division.
{ { parts. { 2. By divided { Cuttings
{ { { parts.-- { proper:
{ { { _Cuttage._ { Of tubers.
_B._ { { { { Of roots.
By Buds. { { { { Of stems.
{ { { { Of leaves.
{
{ { { I. Budding: Shield, flute,
{ { { veneer, ring, annular,
{ { { whistle or tubular.
{ { {
{ { { II. Grafting:
{ { { Whip.
{ II. On roots { { Saddle.
{ of other { 1. By detached { Splice.
{ plants.-- { scions. { Veneer.
{ _Graftage._ { { Cleft.
{ { { Bark.
{ { { Herbaceous.
{ { { Seed.
{ { { Double.
{ { { Cutting.
{ { 2. By undetached scions.--Inarching.
CHAPTER I.
SEEDAGE.
=Seedage.=--The process or operation of propagating by seeds or spores,
or the state or condition of being propagated by seeds or spores.
There are three external requisites to the germination of
seeds--moisture, free oxygen, and a definite temperature. These
requisites are demanded in different degrees and proportions by seeds
of different species, or even by seeds of the same species when
differing widely in age or degree of maturity. The supply of oxygen
usually regulates itself. It is only necessary that the seeds shall not
be planted too deep, that the soil is porous and not overloaded with
water. Moisture and temperature, however, must be carefully regulated.
[Illustration: Fig. 1. Double Seed-Pot.]
=Regulation of Moisture.=--Moisture is the most important factor
in seedage. It is usually applied to the seeds by means of soil or
some similar medium, as moss or cocoanut fiber. Fresh and vigorous
seeds endure heavy waterings, but old and poor seeds must be treated
sparingly. If there is reason to suspect that the seeds are weak,
water should not be applied to them directly. A favorite method of
handling them is to sow them in a pot of loose and sandy loam which
is set inside a larger pot, the intermediate space being filled with
moss, to which, alone, the water is applied. This device is illustrated
in Fig. 1. The water soaks through the walls of the inner pot and is
supplied gradually and constantly to the soil. Even in this case it
is necessary to prevent soaking the moss too thoroughly, especially
with very weak seeds. When many pots are required, they may be simply
plunged in moss with the same effect. The soil should be simply very
slightly moist, never wet. Moisture is sometimes supplied by setting
the seed-pot in a shallow saucer of water, or it may be sufficient to
simply place it in the humid atmosphere of a propagating-box. Large
seeds may be laid upon the surface of the soil in a half-filled pot,
covered with thin muslin, and then covered with loose and damp loam.
Every day the pot is inverted, the covering taken off and fresh soil
is added. A modification of this plan for small seeds can be made by
placing the seeds between two layers of thin muslin and inserting them
in damp loam, which is frequently renewed to avoid the extremes which
would result from watering or from allowing the soil to become dry.
In these last operations, no water is applied to the seeds and they
constitute one of the most satisfactory methods of dealing with seeds
of low vitality. They are essentially the methods long ago used by
Knight, who laid such seeds between two sods cut from an old and dry
pasture.
Even sound and strong seeds should be watered with care. Drenchings
usually weaken or destroy them. The earth should be kept simply damp.
To insure comparative dryness in in-door culture, some loose material,
as pieces of broken pots or clinkers, should be placed in the bottom of
the pot or box to afford drainage. It should be borne in mind, however,
that the seed bed should be approximately equally moist throughout its
depth. The waterings should therefore be copious enough to moisten the
soil throughout. A wet or moist surface over a dry substratum should
always be avoided. Error is common here. It is usually best to apply
water with a watering-pot, as watering with a hose is apt to wash out
the seeds and to pack the soil, and the quantity of water is not so
easily regulated.
At first thought, it would appear that the apparently good results
following soaking of seeds in many cases, are a contradiction of these
statements that seeds may be over-watered. But soaking is usually
beneficial only when practiced for a comparatively short time. It is
not good practice to soak delicate seeds before sowing, and it is of
doubtful utility in most other cases, unless it is necessary to soften
the integuments of hard-shelled species, as discussed on page 17. The
gain in rapidity of germination following soaked, as compared with dry
seeds, is really fictitious, inasmuch as germination actually begins in
the soaked seeds before the dry samples are sown. The soaked seeds are
sown in water rather than in soil, and as conditions are more uniform
there, a gain apparently due to soaking may result. In the case of
strong seeds which must be planted out-doors in cold or uncongenial
soil, a preliminary soaking of from 12 to 24 hours may be beneficial,
as it lessens the period which the seeds would otherwise pass in
untoward conditions. But soaked seeds, unless of very hardy species,
should never be sown out-doors until the soil has become rather dry and
warm.
To prevent too rapid drying out, the soil should be firmly pressed
about the seeds. The pot or box should be given a shady place, or some
covering may be applied to check evaporation. A pane of glass is often
placed over the box, being tilted a little at intervals to allow of
ventilation and to prevent the soil from becoming soggy or "sour." A
seed-case, with a glass cover, as shown in Fig. 2, is neat and handy in
the treatment of small seeds. A thin covering of fine moss is sometimes
given, or a newspaper may be thrown over the soil.
[Illustration: Fig. 2. Seed-Case.]
In out-door culture, only a naturally dry and well-drained soil should
be chosen for all ordinary seeds, especially for such as are sown
in the fall or remain in the ground a long time before germinating.
Soils which contain a liberal amount of sand or gravel are especially
valuable for this purpose.
To prevent drying in out-door culture, it is important that the earth
be well firmed over the seeds. Walking on the row, placing one foot
directly ahead of the other, is usually the most expeditious and
satisfactory operation, at least with large seeds. Or the earth may
be firmed with a hoe or the back of a spade, or a board may be placed
upon the row and then be thoroughly settled by walking over it. In
the sowing of celery and other small and slow seeds, it is a frequent
practice to leave the board on the row until the seeds appear in order
to hold the moisture. This is a doubtful expedient, however, for the
young plants are apt to be quickly dispatched by the sun when the board
is removed. If the board is employed, it should be raised an inch or
two from the ground as soon as the plants begin to appear. But the
shade of the board is too dense and plants do not grow stocky under it.
It is better to use brush or lath screens if protection is desired;
or fine litter, if free from weed seeds, may be used. In most cases,
however, screens will not be needed by celery and similar seeds if the
ground is in the proper condition and is well firmed at planting time.
It is always advisable, nevertheless, to place the beds for slow and
small seeds where they can be watered occasionally.
[Illustration: Fig. 3. Lath Screen.]
There are many kinds of screens in use to prevent the drying out of
small seeds in out-door seedage and to protect the young seedlings.
These are used also in the shading of cuttings. The common lath screen
(Fig. 3) is the most useful for general purposes. It is simply a square
frame made from common laths laid at right angles in a double series.
The interstices between the laths are equal in width to the laths
themselves. These screens are laid horizontally upon a light frame-work
a few inches above the seeds. The passage of the sun constantly moves
the shadows over the bed, and sufficient shade is afforded while
thorough ventilation is allowed. This and all other elevated screens
are useful in shading and protecting the young plants as well, but when
used for this purpose they are usually raised a greater distance above
the beds. A brush screen consisting of a low frame covered with boughs,
is often used, as shown in Fig. 4. This is cheaper than the lath
screens, and is equally as good for most purposes. The brush is often
laid directly upon the ground, especially in large beds. This answers
the purpose of shading, but it does not allow of weeding and it must
be taken off soon after the seeds germinate, or slender plants will be
injured in its removal. Brush screens are sometimes raised three or
four feet to allow of weeding. A screen for frames is shown in Fig.
5. It is a simple covering of muslin stretched over the top and sides
of a rough frame-work. The cloth is usually omitted from the front
side. This style of screens is much used by nurserymen, especially for
cutting beds. Whitewashing the sashes also affords good shading. A more
elaborate and permanent screen is shown in Fig. 6. It is built of
slats, usually 3-inch stuff. This shed screen is oftenest used for the
protection of tender plants, but it affords an exceedingly useful and
convenient place for the storage of pots and boxes of slow-germinating
seeds.
[Illustration: Fig. 4. Brush Screen.]
[Illustration: Fig. 5. Screen for Frames.]
[Illustration: Fig. 6. Shed Screen.]
Various frames and covers are employed for in-door seedage, but
they are designed to regulate atmospheric moisture and to control
temperature. They are more commonly employed in the growing of
cuttings, and are therefore described in Chapter IV.
=Requirements of Temperature.=--Variations in temperature exercise less
influence upon seeds than variations in moisture. Yet it is important
that the extremes of temperature should not be great, especially in
small, delicate or weak seeds. Seeds will endure greater extremes of
temperature when dry than when moist. This indicates that germinating
seeds must be kept in a comparatively uniform temperature. For this
reason it is poor practice to place seed-boxes in a window in full
sunlight. Partial or complete shade serves the double purpose of
preventing too great heat and too rapid evaporation. Various covered
seed-boxes are used for the purpose of maintaining approximately the
required temperature, but as they are oftener used in bud-propagation,
they are discussed in that connection.
Bottom heat is helpful to germination in most seeds, but, except in
the case of certain tropical species, it should not be strong. It is a
common practice to place the seed-boxes on moderately cool pipes under
benches in a greenhouse. Seeds of hardy annuals and perennials do not
require bottom heat, although they may be benefitted by it. If the
soil in seed beds should become too cool, watering with warm or tepid
water will be found helpful.
It is impossible to give rules for the determination of the proper
temperature for different kinds of seeds. In general, it may be said
that seeds germinate most rapidly at a temperature a few degrees above
that required for the best development of the plant itself. Hardy
plants require a temperature of from 50° to 70°, conservatory plants
from 60° to 75° or 80°, and tropical or stove plants from 75° to 95°.
The plantlets should be removed from these highest temperatures, as a
rule, as soon as germination is completed.
In out-door culture, depth of planting has a direct relation to
temperature. Seeds may be planted deeper late in the season than early,
when the soil is cold and damp. Deep planting probably as often kills
seeds because of the absence of sufficient heat as from the lack of
oxygen or the great depth of earth through which the plantlet is unable
to push.
=Preparatory Treatment of Seeds.=--Many seeds demand some treatment
preparatory to sowing. Nearly all hard and bony seeds fail to
germinate, or at least germinate very irregularly, if their contents
are allowed to become thoroughly dry and hard. The shells must also be
softened or broken in many cases before the embryo can grow. Nature
treats such seeds by keeping them constantly moist under leaves or
mold, and by cracking them with frost. This suggests the practice
known to gardeners as _stratification_, an operation which consists in
mixing seeds with earth and exposing them to frost or to moisture for a
considerable time.
Stratification is practiced, as a rule, with all nuts, the seeds of
forest trees, shrubs, the pips of haws and often of roses, and in
many cases with the seeds of common fruits. It should be performed as
soon as possible after the seeds are mature. Small seeds are usually
placed in thin layers in a box alternating with an inch or two of sand.
Sometimes the seeds are mixed indiscriminately in the sand, but unless
they are large it is difficult to separate them out at sowing time.
The sand is often sown with the seeds, however, but it is difficult
in such cases to distribute the seeds evenly, and in sowing large
quantities the handling of the sand entails a considerable burden and
becomes an item of expense. It is advisable to pass the sand through a
sieve of finer mesh than the seeds, and the seeds can then be sifted
out at sowing time. If the seeds are very small or very few in number
they may be placed between folds of thin muslin, which is then laid
in the sand. Any shallow box, like a gardener's "flat," is useful in
making stratifications, or with small lots of seeds pots may be used.
A flat four inches deep might contain two or three layers or strata of
seeds the size of peas.
The disposition of the boxes when filled varies with different
operators. Some prefer to bury them. In this case a well-drained sandy
slope is chosen. The flats are placed in a trench from one to two feet
deep, covered with a single thickness of boards, and the trench is
then filled with earth. The seeds usually freeze somewhat, although
freezing is not considered necessary unless in the case of nut-like
seeds. The object attained in burying is to keep the seeds moist and
fresh, inducing the rotting or softening of the coverings, while they
are buried so deep that they will not sprout. Seeds of most forest
trees should be treated in this manner. They are commonly left in the
ground until the second spring, when they are taken up and sown in
drills in mellow ground. If good loam to which has been added a little
well-rotted manure is used, the seeds or nuts of hardy trees and shrubs
may be allowed to germinate and grow for one season in the flats. At
the end of the season or the next spring the plants can be transplanted
without losing one. This is, perhaps, the best way to handle rare and
difficult subjects.
Many growers place the boxes on the surface in some protected place, as
under trees or in a shed, and cover them a foot deep with clean straw
or leaves. This is a good method for all seeds which are to be sown the
following spring, as those of many fruits. If boxes are piled on top
each other they should be mulched with moss, else the under ones may
become too dry. Or the boxes may be placed without covering in a shed,
but they must be examined occasionally to see that they do not become
too dry. Precaution must also be taken to keep away mice, squirrels,
blue-jays and other intruders.
Large nut-like seeds or fruits, like peach-pits, walnuts and
hickory-nuts, are usually buried in sand or light loam where they will
freeze. Or sometimes the large nuts are thrown into a pile with earth
and allowed to remain on the surface. Freezing serves a useful purpose
in aiding to crack the shells, but it is not essential to subsequent
germination, as is commonly supposed. All seeds, so far as known, can
be grown without the agency of frost if properly handled.
Fall sowing amounts to stratification, but unless the soil is mellow
and very thoroughly drained the practice is not advisable. The seeds
are liable to be heaved or washed out, eaten by vermin, and the soil is
apt to bake over them. Under proper conditions, however, the seeds of
fruits and many forest trees thrive well under fall sowing. The seeds
should be sown as soon as they are ripe, even if in mid-summer; or if
the ground is not ready for them at that time, they may be temporarily
stratified to prevent too great hardening of the parts. It is best,
however, to allow all green or moist seeds to dry off a few days before
they are stratified. Fall sown seeds should always be mulched.
Some seeds rarely germinate until the second year after maturity,
even with the best of treatment. The thorns, mountain ash, hollies,
viburnums, some roses, and many others belong to this category. Some
growers sow them regularly as soon as they are ripe and allow the beds
to remain until the seeds appear. This is a waste of land and of labor
in weeding, and the best way is to stratify them and allow them to
remain until the second spring before sowing.
Partial substitutes for stratification are soaking and scalding the
seeds. Soaking may be advantageously practiced in the case of slow and
hard seeds, which are not enclosed in bony shells, and which have been
allowed to become dry. Seeds of apple, locust and others of similar
character, are sometimes treated in this manner. They are soaked for 24
or 36 hours, and it is commonly supposed that if they are exposed to a
sharp frost in the meantime, better results will follow. While still
wet the seeds are sown. Scalding water may be poured over locust and
other seeds to soften their covering. But seeds should not be boiled,
as sometimes recommended.
[Illustration: Fig. 7. Bored Seed.]
The germination of bony seeds is often facilitated by filing or cutting
away the shell very carefully near the germ, or by boring them. A bored
nelumbium seed is shown in Fig. 7.
Treatment with various chemicals has been recommended for the purpose
of softening integuments, and also for some power which strong
oxidizing agents are supposed to exert in hastening germination
itself, but the advantages are mostly imaginary. Secret and patented
"germinator" compounds had better be avoided.
Pulpy and fleshy coverings should be removed from seeds before sowing.
Soft fruits, like berries, are broken up or ground into a pulp and
the seeds are then washed out. This separation may be performed
immediately in some cases, but when the pulp adheres to the seed,
the whole mass is usually allowed to stand until fermentation and
partial decay has liberated the seeds. The pulp will then rise, in
most instances, leaving the seeds at the bottom of the vessel. Seeds
can be liberated quickly by adding a stick of caustic potash to each
pail of water. After the mass has stood an hour or so, the seeds can
be rubbed out easily. Even tomato seeds can be cleaned with safety in
this manner. Seeds which have thin coverings, as the viburnums and many
haws, can be prepared by rubbing them through the hands with sharp
sand. Or the scant pulp of such seeds may be allowed to rot off in the
stratification box. Fleshy coverings of hard and bony seeds may be
removed by maceration. Allow them to stand in water at a temperature
of about 75° for one to three weeks, and then wash them out. Resinous
coverings are sometimes removed by mixing the seeds with fresh ashes or
lime, or by treating them with lye. Hard, thick-walled seeds are rarely
injured by the decay of the pulpy covering, but thin-walled seeds
should be cleaned, to avoid the possibility of damaging them.[A]
[A] An admirable paper upon the propagation of hardy trees and shrubs
from seeds and the treatment of the young seedlings, by Jackson Dawson,
may be found in Trans. Mass. Hort. Soc. 1885, part 1, 145, and also in
Rep. Sec. Mass. Bd. Agr. 1885, 468.
=Sowing.=--The soil in which seeds are sown, especially in in-door
culture, should be such as to allow of perfect drainage and at the same
time to hold moisture. Good potting soil, with a liberal allowance of
sharp sand, is the best for general purposes. Pure sand becomes too
dense, and leaf mold alone is usually too loose and open. A proper
combination of the two corrects both faults. It is impossible to
describe a good potting or seed-bed soil. Some experience is essential
to the best results in preparing it. It should be of such character
that when a damp portion is firmly compressed in the hand it will fall
apart when released. It should never bake. Good old garden loam, to
which an equal quantity of sand has been added, is usually a good soil
for common in-door seedage. There should be no manure in soil used for
seeds which produce a delicate growth, as rhododendrons and kalmias. In
all such cases, rotted sod or leafy peat forms the best basis. The soil
should be sifted and thoroughly fined before seeds are put into it.
Seeds usually require lighter soil than that in which the growing plant
will flourish. Cocoanut fiber is sometimes used in place of the soil,
as it holds moisture, allows of almost perfect drainage, and does not
become "sour." Fine dead sphagnum moss may also be used. Orchid seeds
are usually sown on the live moss in which the parent plant is growing;
or they may be sown on damp wood or cork. (See under Orchids, Chap.
VI.) Small seeds, like those of cineraria and calceolaria, germinate
well in very old cow-dung obtained from a pasture; the unctuous
matters have disappeared, leaving a fibrous remainder. But all things
considered, well-prepared soil is the most satisfactory medium which
can be used. Seeds of aquatic plants which are to be sown in a pond may
be placed in a ball of clay and dropped into the water.
Shallow boxes or "flats" and earthen seed-pans and lily-pans are
usually preferable to pots in which to grow seeds. They give more
surface in proportion to their contents and require less attention in
drainage. If pots are used, the four to six inch sizes are best.
If delicate seeds are sown out-doors, they should be given some
protection, if possible. An ordinary hot-bed frame gives the best
results. In warm weather or a sunny exposure it will be found desirable
to substitute a cloth screen for the sash. A thin or medium water-proof
plant cloth, either commercial or home-made, is excellent for this
purpose. It may be tacked upon a simple and light rectangular frame
which is strengthened at the corners by iron "carriage-corners." These
cloth-covered frames are handy for many purposes, particularly for
protecting and supplying some warmth to seed-pans and young seedlings.
It is essential that good drainage be given all in-door seed-pots or
seed-beds. A layer of broken pots or other coarse material is placed on
the bottom. Many growers place a thin layer of fine dead sphagnum moss
or of peat over this drainage material, and it certainly makes a useful
addition. It is particularly useful in isolated pots or small boxes,
as it holds enough moisture to prevent too rapid drying out, while all
surplus water is quickly taken off by the coarse material beneath. Over
the moss coarse siftings from the soil may be placed, while on top only
the finest and best soil should be used. The smaller the seeds, the
more care must be exercised in the sowing.
The proper depth for sowing varies directly with the size of the seed.
The chief advantage of very fine soil for small seeds is the greater
exactness of depth of covering which it allows. Very small seeds should
be sown upon the surface, which has previously been well firmed and
levelled, and then covered with a very thin layer of finely sifted soil
or a little old and dead moss rubbed through a sieve. This covering
should be scarcely deeper than the thickness of the seeds; that is, the
seeds should be barely covered. Many prefer pressing the seeds into the
soil with a block. Or if one has a close propagating-box, the seeds
may remain upon the surface and sufficient moisture will be supplied
from the atmosphere. Such fine seeds are rarely watered directly, as
even the most careful treatment would be likely to dislodge them. The
soil is usually well watered before the seeds are sown, or moisture may
be supplied by inserting the pot in water nearly to its rim for a few
moments. If water is applied from a hose, a thin cloth should first
be spread on the soil to hold it. Celery seeds, in out-door beds, are
often sown upon a nicely prepared surface and are then pressed in by
means of the feet or a board. Some cover to prevent evaporation should
be given all small seeds. This may be a board or a slate slab at first,
but as soon as the plants appear glass should be substituted to admit
light. (See pp. 11 to 14.)
Large seeds demand much less care as to depth of covering, as a rule.
One-fourth or one-half inch is a good depth for most coarse seeds
in-doors. If one wishes to gauge the depth accurately, the drills
may be made by a planting stick, like that shown in Fig. 8. Its
flange is made of the required thickness, and it is pressed into the
soil until the cap strikes the surface. This is a useful implement
in seed testing. Another device for regulating the depth of sowing,
particularly in seed testing, is the Tracy planter, shown in Fig. 9.
It consists of two strips of heavy tin plate about three inches wide,
hung upon two wire pivots or hinges some two inches long. At their
upper edges and equidistant from either end, the plates are joined by
a firm spiral spring, which serves to throw the upper edges apart, and
to cause the lower edges to join. This trough is now filled with the
required number of seeds, and is then inserted into the earth to a
given depth, when the fingers push inward on the spring and the trough
opens and delivers the seeds.
[Illustration: Fig. 8. Planting Stick.]
=Miscellaneous Matters.=--The influence which light exerts upon
germination is not definitely understood. It is known, however, that
seeds will often germinate in full sunlight, if the proper conditions
of moisture and temperature can be maintained. Seeds sown upon a
moist surface and covered with a glass present an interesting study.
But it is well known, on the other hand, that some seeds will not
germinate, or will at least appear unevenly, if subjected to sunlight.
At least some of the delphiniums, papavers and adonises germinate very
imperfectly, if at all, in direct light. It is always advisable to keep
germinating seeds in shade or partial darkness, especially as there is
nothing to be gained by exposing them. Of course the soil itself is
sufficient protection if the seeds are covered.
[Illustration: Fig. 9. Tracy Planter.]
It is a common statement that seeds can never revive if allowed to
become thoroughly dry after they have begun to sprout. This is an
error. Wheat, oats, buckwheat, maize, pea, onion, radish and other
seeds have been experimented upon in this direction, and they are found
to re-germinate readily, even if allowed to become thoroughly dry and
brittle after sprouting is well progressed. They will even re-germinate
several times. Wheat, peas and other seeds have been carried through so
many as seven germinations after the radicle had grown a half inch or
more and the seeds had been sufficiently dried in each trial to render
them fit for grinding.
Damping-off is a common ailment of young seedlings and cuttings. The
stem becomes brown and constricted at or near the surface of the
soil, and it soon rots and falls over. The top of the plant often
remains alive and fresh for several days after it has fallen. A
fungus is supposed to cause damping-off. The conditions which seem to
particularly favor the development of this fungus are a moist and close
atmosphere, crowding and careless watering. Plants are particularly
liable to damp-off if only sufficient water is applied to keep the
surface moist while the under soil remains dry. Hot sand, sifted over
the plants, will check it, but there is no complete remedy. Attention
to the above suggestions will serve as a preventive.
The transportation of certain kinds of seeds over long distances,
especially on sea voyages, is often beset with difficulties.
Thick-meated or soft seeds may become too dry if stored in a warm
place or too moist if stored in a cool one. The humid atmosphere of
the ocean is fatal to some seeds unless they are well protected, and
the moist and hot climates of some tropical countries destroy many
seeds of cooler regions before they can be planted. Thin-coated seeds
demand dryness and air, and bony seeds usually need moisture and a
more confined atmosphere. Most seeds may be sent dry and loose in
coarse paper packages under all ordinary circumstances; but if they
are to traverse very hot and moist climates, they should be sealed in
tin cases or very securely wrapped in oiled paper, in which case the
seeds should be thoroughly dried before being packed. Small seeds which
are liable to become moldy may be packed in finely powdered charcoal.
Apple and pear seeds are often imported in this manner. The seeds or
fruits of woody plants require more careful management. They should
generally be transported in some sort of stratification. A favorite
method is to place them in boxes or jars, mixed with naturally moist
sand or sawdust, or slightly moist dead sphagnum moss. Some prefer to
seal the packages hermetically, but under ordinary conditions this is
unnecessary. In transit, the packages should be stored in a medium
and uniform temperature. Even acorns, which are often difficult to
transport over long voyages, may be carried in this manner with safety.
It is important that the soil should not be wet. Natural soil from a
dryish and loamy pasture is excellent. In some cases it is better to
sprout the seeds in the native country and ship the seedlings in a
closed or Wardian case.
It should be borne in mind that actual plantings rarely give so good
results as seed tests, from the fact that conditions are more variable.
There is often a variation of over fifty per cent. even when the
planting has been carefully done. This is proof that liberal seeding
should always be practiced.
=Spores.=--Ferns, lycopodiums and selaginellas are often grown from
spores. The general conditions adapted to the germination of seeds are
also suitable for the germination of spores, but extra care must be
taken with the drainage. If a pot is used, it should be half or more
filled with drainage material, and the soil should be rendered loose
by the addition of bits of brick, charcoal, cinders or other porous
materials. The surface soil should be fine and uniform. Some place a
thin layer of brick dust upon the surface, in which the spores are
sown. It is a frequent practice to bake the soil to destroy other
spores which might cause troublesome growths. The spores should be
sprinkled upon the surface and should not be covered. The pot should be
set in a saucer of water and it should be covered by paper or a pane
of glass if the sun strikes it. Better results are obtained if the pot
or pan is placed inside a propagating-frame or under a bell-glass. In
place of earth, a block or small cubes of firm peat or sandstone may
be employed. The block is placed in a saucer of water and the spores
are sown upon its surface. Water should not be applied directly to the
spores, as it is apt to dislodge them.
The period of germination varies in different species, but three to six
weeks may be considered the ordinary limits. While still very small,
the plantlets should be pricked out, and for some time thereafter they
should be subjected to the same conditions as before. Spores are so
exceedingly small and light that the greatest care must be exercised in
growing them. In order to gather them, the fronds may be cut as soon as
the sori or fruit-dots turn brown, and stored in close boxes or paper
bags.
Note.--For tables of weights and longevities of seeds and quantities
required for given areas, consult Horticulturist's Rule-Book.
CHAPTER II.
SEPARATION.
=Separation.=--The act or process of multiplying plants by means of
naturally detached asexual organs, or the state or condition of being
so multiplied.
Separation is effected by means of bulbs, bulbels, bulb-scales,
bulblets, corms, tubers, offsets, crowns and sometimes by buds.
Bulbs of all kinds are specialized buds. They are made up of a short
and rudimentary axis closely encased in transformed and thickened
leaves or bulb-scales. These thickened parts are stored with nutriment
which is used during subsequent growth. Bulbs occur only in plants
which are accustomed to a long period of inactivity. Many bulbous
plants are peculiar to dry and arid regions, where growth is impossible
during long periods. A bulb is, therefore, a more or less permanent and
compact leaf-bud, usually occupying the base of the stem underground
and emitting roots from its lower portion. Bulbs are conveniently
divided into two great classes--the scaly, or those composed of narrow
and mostly loose scales, as in the lily, and laminate or tunicate, or
those composed of more or less continuous and close-fitting layers or
plates, as in the onion.
[Illustration: Fig. 10. Bulb of Lilium candidum.]
Bulbs often break up or divide themselves into two or more nearly equal
portions, as in _Lilium candidum_, shown one-third natural size in
Fig. 10. The parts may be separated and treated as complete bulbs for
purposes of propagation. This division or separation of bulbs proceeds
in a different manner in nearly every species, yet it is so obvious
that the novice need not be perplexed by it. Almost any breaking apart
of these loose bulbs, if only a "heart" or central axis remains in each
portion, is successful for purposes of slow multiplication; but when
flowers are desired it is usually inadvisable.
Bulbous plants multiply most easily by means of _bulbels_--often also
called bulbules and offsets--or small bulbs which are borne about a
large or mother bulb. In some lilies, as _Lilium candidum_, the bulbels
form at the top or crown of the mother bulb, and a circle of roots
will be found between them and the bulb; in others, as _L. speciosum_
and _L. auratum_, they form on the lower part of the flower stalk.
In some species the bulbels are few and very large, or even single,
and they bloom the following year. In such cases the bulb undergoes a
progressive movement from year to year after the manner of root-stocks,
the bulb of one year forming a more or less distinct one above and
beyond it which continues the species, while the old one becomes weak
or dies. This method of bulb formation is seen in the cut of _Lilium
pardalinum_, Fig. 11. In the hyacinth the bulbels form at the base of
the bulb.
[Illustration: Fig. 11. Bulb of Lilium pardalinum.]
Bulbels vary greatly in size and frequency in different species.
Sometimes they are no larger than a grain of wheat, and in other plants
they are as large as hickory-nuts. In some species they are borne
habitually underneath the scales of the mother bulb. These bulbels
are often removed when the mother bulbs are taken up, and they are
usually planted in essentially the same manner as the bulbs themselves,
although it is desirable to place them, at least for the first year,
in a bed or border by themselves. Or if they are especially small and
delicate they may be planted in pots or flats and be treated about the
same as single eye cuttings. In some lilies the bulbels are allowed
to remain attached and the whole mass is planted in the fall in close
drills. Sometimes the larger lily bulbels will produce flowers the
following season, but they usually require the whole of the season in
which to complete their growth. The second fall they are ready to be
permanently planted. Bulbels of some plants require a longer time in
which to mature into bulbs.
[Illustration: Fig. 12. Cut Hyacinth Bulb.]
[Illustration: Fig. 13. Hollowed Hyacinth Bulb.]
Bulbels are often produced by an injury to the bulb. Growth of stem
and leaves is prevented or checked and the energy is directed to the
formation of minute buds, or bulbs, in the same manner as adventitious
buds form upon a wounded stem. Advantage is taken of this fact to
multiply some bulbous plants, and in the case of the hyacinths, at
least, the mutilation of bulbs for this purpose is practiced to a
commercial extent. Hyacinth bulbs are cut in two, or are slashed
in various ways. The favorite method is to make two or three deep
transverse cuts into the base of the bulb. The strongest bulbs should
be chosen and the operation is performed in spring or early summer
when the bulb is taken up. The bulbs are sometimes hollowed out from
the under side for half or more of their length. This operation is
sometimes performed later in the season than the other, and precaution
should be exercised that the bulbs do not become too moist, else they
will rot. Hollowed bulbs should be well dried before being planted.
Both methods of preparing hyacinth bulbs are shown in Figs. 12 and 13
which are adapted from Gardeners' Chronicle. Fig. 14 shows a portion
of the base of a cross-cut bulb, with the adventitious bulbels. The
mutilated bulbs are stored during summer, and are planted in fall or
spring. The wounded bulbs produce very little foliage, but at the end
of the first season the bulbels will have formed. The bulbels are then
separated and planted by themselves in prepared beds. Several years
are required for the bulbels to mature into flowering bulbs. Some of
the strongest ones may produce flowering bulbs in three years, but
some of them, especially those obtained from the hollowed bulbs, will
not mature short of six years. This method of propagating hyacinths is
confined almost entirely to Holland.
[Illustration: Fig. 14. Cross-Cut Bulb.]
The scales of bulbs are often employed to multiply scarce varieties.
From ten to thirty of the thicker scales may be removed from the
outside of the bulb without serious injury to it. These are treated
in the same manner as single eye cuttings. They are usually handled
in flats or propagating-frames, and are pressed perpendicularly into
a light and loose soil--half sharp sand and half leaf-mould--for
nearly or quite their entire length, or are scattered in damp moss.
Keep the soil simply moist, and for hardy and half-hardy species keep
the temperature rather low--from 45° to 60°. Slight bottom heat may
sometimes be given to advantage. In from three to ten weeks a little
bulbel, or sometimes two or more, will appear at the base of the scale,
as shown in Fig. 15.
[Illustration: Fig. 15. Bulb-Scale.]
These pots or flats may be plunged out-doors during summer if the
planting was done in winter, or the scales may be potted off or
transferred to the open border as soon as rootlets have formed. It is
the common practice with most hardy species to allow the scales to
remain in the original flats during summer and to cover them the next
fall, allowing them to remain out-doors over winter. The succeeding
spring they are shifted into a bed or border, and by the next
fall--having had two summers' growth--most species will be ready for
permanent planting in the flower border.
A _bulblet_ is a small bulb borne entirely above ground, usually in the
axil of a leaf or in the inflorescence. Familiar examples occur in the
tiger lily and in "top" onions. In the former instance the bulblets are
direct transformations of buds, while in the onion they are transformed
flowers. It is impossible to draw any line of separation between
bulblets and buds. In some plants, certain buds detach themselves
and fall to the ground to multiply the species. Sometimes these buds
vegetate before they fall from the plants, as in the case of various
ferns. For purposes of propagation, bulblets are treated in the same
way as bulbels, and like them, they reproduce the variety upon which
they grow. They will develop into full grown bulbs in from one to three
years, according to the species.
[Illustration: Fig. 16. Gladiolus Corm.]
A _corm_ is a bulb-like organ which is solid throughout. Familiar
examples occur in the gladiolus and crocus. Cormous plants are
multiplied in essentially the same manner as bulbous species. As a
rule, a new corm is produced each year above the old one, and this
commonly bears flowers the following season. This renewal is well
shown in the gladiolus, Fig. 16. The illustration shows a gladiolus
bottom, half size, when taken up in November. At the base are seen the
withered remains of the corm which was planted in the spring, and above
it the new corm which will furnish bloom the following season. A number
of _cormels_ or "spawn" have also appeared. These may be planted out in
a border or bed and will produce mature bulbs in one or two seasons.
The larger ones, under good treatment, will often produce bulbs an inch
in diameter the first season. Some growers keep the cormels a year and
a half before planting them out, as they are thought to vegetate more
evenly under such treatment; in this case they should be placed in sand
to prevent too great drying out.
Adventitious cormels may be produced by various methods of wounding the
mother corm, and this practice of exciting them is often necessary,
as some varieties do not produce cormels freely. Each bud on the top
or side of the corm may be made to produce a separate corm by cutting
a deep ring around it, so as to partly divide it. Or the corm may be
directly cut into as many separate pieces as there are buds or eyes,
after the manner of cutting potatoes, but these pieces are usually
handled in flats where temperature and moisture can be controlled.
Almost any injury to such vigorous corms as those of the gladiolus and
crocus will result in the production of cormels, if care is taken that
the corms do not become so cold and wet that they will rot.
A _tuber_ is a prominently thickened portion of a root or stem, and it
is usually subterranean. The potato, sweet potato and dahlia furnish
good examples. Tuberiferous plants are multiplied by planting these
tubers whole, or the tubers may be cut into small portions as described
in Chapter IV, in the descriptions of cuttings. In hardy species, the
tubers may be allowed to remain in the ground during winter, but they
are generally dug in the fall and stored in a dry and cold place, but
where they will not freeze.
An _offset_ is a crown or rosette of leaves, usually borne next the
surface of the ground, which detaches itself and forms an independent
plant. The best examples occur in the house-leeks, plants which are
more familiarly known as "hen and chickens" and "man and wife." These
offsets take root readily, and in propagating there is no other care
necessary than to remove and plant them.
A _crown_ is a detachable portion of a root-stock bearing roots and
a prominent bud. Rhizomes or root-stocks multiply individuals and
extend the distribution of the species by means of a progressive
movement of the crowns. The root-stock grows during summer, and at the
end of the season each branch develops a strong terminal bud which
usually produces a flowering stem the following season. The root-stock
gradually dies away at its old extremity, and in a few years a single
individual gives rise to a considerable patch. This is well shown by
the common May-Apple or podophyllum.
[Illustration: Fig. 17. Lily of the Valley Crown.]
In some species these crowns are removed in the autumn and are planted
and handled in much the same manner as bulbs. The crown or pip of the
lily of the valley, shown half size in Fig. 17, is obtained in this
manner.
CHAPTER III.
LAYERAGE.
=Layerage.=--The operation or practice of making a layer, or the
state or condition of being layered.
=Layer.=--A shoot or root, attached to the parent plant, partially or
wholly covered with earth with the intention that it shall take root
and then be severed from the parent.
=Stolon.=--A decumbent shoot which, without the aid of man, takes
root and forms an independent plant.
Many plants habitually propagate by means of decumbent shoots and
runners. These shoots become more or less covered with earth or leaves,
and roots are emitted, usually at the joints. In many cases, the old
shoots die away and an entirely independent plant arises from each mass
of roots. In other plants, the shoots remain attached to the parent,
at least for a number of years, so that the plant comprises a colony
of essentially distinct individuals. Great numbers of plants which
do not propagate naturally by means of layers are readily increased
by this means under the direction of the grower. In most cases it is
only necessary to lay down the branches, cover them with earth, and
allow them to remain until roots are well formed, when they can be
severed from the parent. Layering is one of the simplest methods of
propagation, as the mother plants nurse the layer plants until they
can sustain themselves. It is a ready means of multiplying hard-wooded
plants which do not grow well from cuttings.
All vines, and all plants which have runners or long and slender shoots
which fall to the ground, may be multiplied readily by layerage. Among
fruits, the black-cap raspberry is a familiar example. The canes of
the current year bend over late in summer and the tips strike the
earth. If the tip is secured by a slight covering of earth, or if it
finds lodgment in a mellow soil, roots are emitted and in the fall a
strong bud or "crown" or "eye" is formed for next year's growth. The
parent cane is severed in the fall or spring, some four or six inches
above the ground, and an independent plant, known as a "root-tip," as
shown in Fig. 18, is obtained. In this instance, as in most others,
it is immaterial at what point the parent stem is severed, except
that a short portion of it serves as a handle in carrying the plant,
and also marks the position of the plant when it is set. The black
raspberry propagates itself naturally by means of layers, and it
is only necessary, in most cases, to bring the soil into a mellow
condition when the tips begin to touch the ground in order that they
may find anchorage. This layering by inserting the growing point has
the advantage of producing very strong "crowns" or plants in autumn
from shoots or canes of the same year, and it should be more generally
practised. Even currants, gooseberries, and many other plants can be
handled in this way.
[Illustration: Fig. 18. Raspberry tip.]
[Illustration: Fig. 19. Covered Layer of Viburnum.]
In most cases of layerage it is necessary to lay down the branches
and to cover them. The covering may be continuous, as in Fig. 19, or
it may be applied only to the joints or restricted portions of the
shoot, as illustrated in Fig. 20. In either case, the covering should
be shallow, not exceeding one to three inches. If the shoot is stiff a
stone or sod may be placed upon it to hold it down; or a crotched stick
may be thrust down over it, as in the "pegging down" of propagators.
[Illustration: Fig. 20. Layered Shoots.]
The strongest plants are usually obtained by securing only one plant
from a shoot, and for this purpose the earth should be applied only
at one point, preferably over a bud somewhere near the middle of the
shoot. If the buds are close together, all but the strongest one may
be cut out. If more plants are desired, however, _serpentine layering_
may be practiced, as shown at A in Fig. 20. The shoot is bent in an
undulating fashion, and from every covered portion roots will form and
a plant may be obtained. The covered layer also possesses the advantage
of giving more than one plant, but the roots are apt to form so
continuously that definite and strong plants are rarely obtained; these
rooted portions may be treated as cuttings, however, with good results.
The grape is sometimes propagated by serpentine layering.
Stiff and hard-wooded plants do not often "strike" or root readily, and
in order to facilitate rooting the branch is wounded at the point where
a new plant is desired. This wounding serves to induce formation of
adventitious buds at that point, and to check the growth of the branch
at the tip. It is a common practice to cut the branch about half in two
obliquely, on the lower side. This operation is known as "tongueing."
"Ringing" or girdling, twisting, notching, and various other methods
are employed, none of which, perhaps, possess any peculiar advantages
in general practice. Some propagators cut all the buds from the covered
portion. In this case the free and protruding end of the layer is
expected to form the top of the new plant. "Arching," or very abrupt
bending, as in serpentine layering, serves the same purpose and is the
only attention necessary in most vines.
When large numbers of plants are desired, as in commercial nurseries,
it is often necessary to cut back the parent plant to the ground,
or very nearly so, for the purpose of securing many shoots fit for
layering. A plant which is cut back in the spring will produce shoots
fit for layering the following spring; or some species will produce
them in abundance the same year if layers of green or immature wood are
desired. These parent or stock-plants are called "stools" by nurserymen.
[Illustration: Fig. 21. Mound Layering of Gooseberry.]
In many species layerage is performed to best advantage by heaping
earth over the stool and around the shoots. This is known as _mound_ or
_stool layering_. The shoots send out roots near the base and straight,
stocky plants are obtained. The English gooseberries are almost
exclusively propagated in this manner in this country. Fig. 21 shows a
row of mound-layered gooseberries. The shoots are allowed to remain in
layerage two years, in the case of English gooseberries, if the best
plants are wanted, but in many species the operation is completed in
a single season. Quinces and Paradise apple stocks are extensively
mound-layered. The practice is most useful in those low plants which
produce short and rather stiff shoots.
As a rule, the best season for making layers is in spring when the
leaves are forming. Rooting progresses rapidly at that season. Many
plants "bleed" if layered earlier in the season. Hardy shrubs may
be layered in the fall, either early or late, and if an incision is
made, a callus will have formed by spring. If rapid multiplication is
desired, the soft and growing shoots may be layered during the summer.
This operation is variously known as "summer," "herbaceous," "green"
and "soft" layering. Comparatively feeble plants usually result from
this practice, and it is not in common favor.
[Illustration: Fig. 22. Pot layerage.]
_Pot layering_, _circumposition_, _air layering_ and _Chinese layering_
are terms applied to the rooting of rigid stems by means of surrounding
them, while in their natural position, by earth or moss, or similar
material. The stem is wounded--commonly girdled--and a divided pot or
box is placed about it and filled with earth (Fig. 22). The roots start
from above the girdle, and when they have filled the pot the stem is
severed, headed back, and planted. Pot layering is practiced almost
exclusively in greenhouses, where it is possible to keep the earth
uniformly moist. But even there it is advisable to wrap the pot in moss
to check evaporation from the soil. Some plants can be readily rooted
by wrapping them with moss alone. Pot layering is employed not only
for the purpose of multiplying plants, but in order to lower the heads
of "leggy" or scraggly specimens. The pot is inserted at the required
point upon the main stem, and after roots have formed abundantly the
top may be cut off and potted independently, the old stump being
discarded.
[Illustration: Fig. 23. Layering pot.]
[Illustration: Fig. 24. Layering cone.]
[Illustration: Fig. 25. Layering cup.]
[Illustration: Fig. 26. Layering cup.]
[Illustration: Fig. 27. Compound layering pot.]
The French have various handy devices for facilitating pot layering.
Fig. 23 shows a layering pot, provided with a niche in the side to
receive the stem, and a flange behind for securing if to a support.
Fig. 24 represents a layering cone. It is made of zinc or other metal,
usually four or five inches high, and is composed of two semi-circular
wings which are hinged on the back and are secured in front, when the
instrument is closed, by means of a hinge-pin. A cord is inserted
in one side with which to hang it on a support. A cup or pot with a
removable side is also used. This is shown open in Fig. 25 and closed
in Fig. 26. An ingenious compound layering pot is shown in Fig. 27. The
main stem or trunk of the plant is carried through the large opening,
and the branches are taken through the smaller pots at the side. Kier's
layering boxes or racks are shown in Figs. 28 and 29. The trays are
filled with earth and the branches are laid in through the chinks in
the border and are treated in the same manner as ordinary out-door
layers. These racks supply a neat and convenient means of increasing
greenhouse plants which do not readily strike from cuttings.
[Illustration: Fig. 28. Kier's layering rack.]
It is well to bear in mind that when layers do not give strong plants,
they can be divided into portions and treated as ordinary cuttings.
This is an important operation in the case of rare varieties which
are multiplied by means of soft or green layers, as some of the
large-flowered clematises and grapes. The weak small plants are handled
in a cool greenhouse or under frames, usually in pots, and they soon
make strong individuals.
[Illustration: Fig. 29. Kier's circular layering rack.]
CHAPTER IV.
CUTTAGE.
=Cuttage.=--The practice or process of multiplying plants by means of
cuttings, or the state or condition of being thus propagated.
=Cutting.=--A severed portion of a plant, inserted in soil or water
with the intention that it shall grow; a slip.
Cuttings, particularly of growing parts, demand a moist and uniform
atmosphere, a porous soil and sometimes bottom heat.
[Illustration: Fig. 30. Hand-glass.]
[Illustration: Fig. 31. Small Propagating-box.]
[Illustration: Fig. 32. Propagating-box.]
=Devices for Regulating Moisture and Heat.=--In order to secure a
uniform and moist atmosphere, various propagating-frames are devised.
Whatever its construction, the frame should be sufficiently tight
to confine the air closely, it should admit light, and allow of
ventilation. The simplest form of propagating-frame is a pot or box
covered with a pane of glass. To admit of ventilation the glass is
tilted at intervals, or two panes may be used and a space be allowed to
remain between them. A common bell-glass or bell-jar (_cloche_ of the
French) makes one of the best and handiest propagating-frames because
it admits light upon all sides and is convenient to handle. These are
in universal use for all difficult and rare subjects which are not
propagated in large numbers. A hand-glass or hand-light (Fig. 30)
answers the same purpose and accommodates a larger number of plants. A
useful propagating-box for the window garden or amateur conservatory is
shown in Fig. 31. A box two or three inches high is secured, and inside
this a zinc or galvanized iron tray, _a_, is set, leaving sufficient
space between it and the box to admit a pane of glass upon every side.
These panes form the four sides of the box, and one or two panes are
laid across the top. The metal tray holds the soil and allows no water
to drip upon the floor. One of the best boxes for general purposes
is made in the form of a simple board box without top or bottom,
and fifteen or eighteen inches high, the top being covered with two
sashes, one of which raises upon a hinge (Fig. 32). Four by three feet
is a convenient size. An ordinary light hot-bed frame is sometimes
constructed upon the bench of a greenhouse and covered with common
hot-bed sash. Propagating houses are sometimes built with permanent
propagating-frames of this character throughout their length.
[Illustration: Fig. 33. Simple Propagating-oven.]
[Illustration: Fig. 34. Propagating-oven.]
In all the above appliances heat is obtained from the sun or from the
bench-pipes or flues of a greenhouse. There are various contrivances
in which the heat is applied locally, for the purpose of securing
greater or more uniform heat. One of the simplest and best of these
is the propagating-oven shown in Fig. 33. It is a glass covered box
about two feet deep, with a tray of water beneath the soil, and which
is heated by a lamp. A similar but somewhat complicated apparatus is
illustrated in Figs. 34, 35, 36. This is an old form of oven, which
has been variously modified by different operators. Fig. 34 shows a
sectional view of the complete apparatus. The box, A A, is made of wood
and is usually about three feet square. L is a removable glass top. B
represents a zinc or galvanized iron tray which is filled with earth in
which seeds are sown or pots are plunged. C is a water tray to which
the water is applied by means of a funnel extending through the box.
A lamp, D, supplies the heat. A funnel of tin, _e e_, distributes
the heat evenly. Holes should be provided about the bottom of the box
to admit air to the flame. A modified form of this device is shown
in Figs. 35 and 36. The water tray, G, slides in upon ledges so that
it can be removed, and the heat funnel, L D L, slides in similarly
and is made to surround the flame like a chimney. The front side of
the apparatus is removable, and the top of the frame, K, is made of
metal. The cover for this apparatus is figured in Fig. 36. The ends,
_a a_, are made of wood, with openings, indicated by the arrows, to
allow of ventilation. The front and top, _g g_, are made of glass. The
frame-work, _c c c_, is made of metal. The cover is hinged on, or held
with pegs, I I, Fig. 35.
[Illustration: Fig. 35. Modified form of Fig. 34.]
[Illustration: Fig. 36. Cover for Fig 35.]
Chauvière's propagating-frame, an apparatus used by the French, is
shown in Fig. 37. It is essentially a miniature greenhouse. The sashes
are seen at _c c_, and above them is a cloth or matting screen. The
sides below the sashes are enclosed, preferably with glass. The bottom
or floor is moveable, and it is sometimes divided into two or three
sections to allow for the accommodation of plants of different sizes
and requirements. These sections are raised or lowered and are held
by pegs. At a is shown a section of floor elevated, and at the left
another section occupying a lower position. Heat is supplied usually
by hot water in the tubes, _d d_. A very elaborate circular French
device, known as Lecoq's propagating-oven, is illustrated in Fig. 38.
It is an interesting apparatus, and is worth attention as showing
the care which has been taken to control the conditions of vegetation
and germination. It is too elaborate for common purposes, and yet for
the growing of certain rare or difficult subjects it might find favor
among those who like to experiment; and it affords an accurate means of
studying plant growth under control. The apparatus is sold in France
for about $6. All the portion below the glass top, _P p_, is made
of earthenware. The base, _a a_, holds a lamp, _d_; _e_ is a water
reservoir to which water is supplied by means of the funnel, _j_. A
vase or rim, _b b_, rests upon the base, and upon it a plate or disc,
_c c_, is fitted. Above this is a glass top, _P p_. Air is admitted
to the apparatus at _i_, _K K_, and between the vase and plate, as at
_c_ on the right. The plate contains two circular grooves, _g g_ and
_h h_. In these grooves the soil is placed or pots plunged. The heat
circulates in the valleys _m_ and _n n n n_, and supplies a uniform
temperature to both sides of the plants.
[Illustration: Fig. 37. Chauvière's Propagating-oven.]
[Illustration: Fig. 38. Lecoq's Propagating-oven.]
[Illustration: Fig. 39. Barnard's Propagating-tank.]
Barnard's propagating-tank, Fig. 39, is a practicable device for
attachment to a common stove. A similar apparatus may be attached to
the pipes of a greenhouse. The tank consists of a long wooden box made
of matched boards, and put together with paint between the joints to
make the box water-tight. The box should be about three feet wide and
ten inches deep, and may be from ten to thirty feet long, according to
the space required. In the middle of the box is a partition, extending
nearly the whole length of the box, and on the inside, on each side,
is a ledge or piece of moulding to support slates to be laid over the
entire surface of the box. The slates are supported by the ledges and
by the central partition, and should be fastened down with cement to
prevent the propagating sand from falling into the tank. One slate is
left out near the end, next the fire, to enable the operator to see the
water and to keep it at the right level. On the slates sand is spread,
in which the cuttings may be struck, the sand nearly filling the box.
At one end of the box is placed a common cylinder stove, with pipe
to the chimney. Inside the stove is a lead or iron pipe (iron is the
best) bent in a spiral. This coil, which is directly in the fire, is
connected by iron pipes with the tank, one pipe leading to one side
of the partition and the other to the opposite side, as shown in the
drawing. If water is placed in the tank it will fill the pipes and form
a continuous circulating system through the pipes and up one side of
the box past the end of the partition, and down the other side. A fire
in the stove causes the water to circulate through the tank and impart
to the bed a genial warmth.
[Illustration: Fig. 40. Zinc Propagating-tank.]
There are various tanks designed to rest upon the pipes in a
greenhouse. The principle of their construction is essentially the
same as of those described in previous pages--bottom heat, a tray of
water, and a bed of soil. Earthenware tanks are commonly employed, but
a recent English device, Fig. 40, is made of zinc. It is about seven
inches deep, and holds an inch or two of water in the bottom. A tray
five inches deep sets into the tank. The water is supplied through a
funnel at the base.
Cuttings usually "strike" better when they touch the side of the pot
than when they are wholly surrounded by soil. This is because the
earthenware allows greater uniformity in moisture than the earth, and
supplies air and a mild bottom heat. Various devices are employed for
the purpose of securing these advantages to the best effect. These are
usually double pots, in one of which water is placed. A good method
is that represented in Fig. 41, which shows a pot, _b_, plugged with
plaster of Paris at the bottom, placed inside a larger one. The earth
is placed between the two, drainage material occupying the bottom,
_a_, and fine soil the top, _c_. Water stands in the inner pot as high
as the dotted line and feeds uniformly into the surrounding soil. The
positions of the water and soil are frequently reversed, but in that
case there is less space available for cuttings. Neumann's cutting-pot
is shown in Fig. 42. This contains an inverted pot in the center, _a_,
designed to supply drainage and to admit heat into the center of the
mass of soil.
[Illustration: Fig. 41. Forsyth's Cutting-pot.]
Some kind of protection, commonly combined with bottom heat, is always
given cuttings made from the soft and growing parts. In in-door work,
any of the devices named above may be employed, but a box like that
shown in Fig. 32 is one of the most useful for common operations. Or
the greenhouse itself may afford sufficient protection, especially if
the cuttings are shaded when first set to check evaporation from the
plant and soil, and to prevent too great heat. This shading is usually
supplied by whitewashing the glass, or a newspaper may be laid over the
cutting bed for a few days. A greenhouse table or bench prepared for
the growing of cuttings is known as a "cutting bench." If the cuttings
become too dry or too hot, they will wilt or "flag." In out-door
work soft cuttings are usually placed in an ordinary cold-frame, and
these frames must be shaded. They may be placed under trees or on the
shady side of a building, or if they are numerous, as in commercial
establishments, a cloth screen should be provided as shown in Fig. 5,
page 13.
[Illustration: Fig. 42. Neumann's Cutting-pot.]
=Soils and General Methods.=--Soil for all cuttings should be
well-drained. It should not be so compact as to hold a great quantity
of water, nor should it be so loose as to dry out very quickly.
It should not "bake" or form a crust on its surface. As a rule,
especially for cuttings made of growing parts, the soil should not
contain vegetable matter, as such material holds too much water and
it is often directly injurious to the cutting. A coarse sharp, clean
sand is the best material for use in-doors. Very fine sand packs too
hard, and should not be used. Some propagators prefer to use fine
gravel, composed of particles from an eighth to a fourth of an inch
in diameter, and from which all fine material has been washed. This
answers well for green cuttings if a propagating-frame is used to
check evaporation and attention is given to watering, because drainage
is so perfect and the material so quickly permeable that uniformity
of treatment is secured. Damping-off is less liable to occur in
such material than in denser soils. The same advantages are to some
extent present in sphagnum moss and cocoanut fibre, both of which are
sometimes used in place of earth. The "silver sand" used by florists
is a very clean and white sand which derives its particular advantages
from the almost entire absence of any vegetable matter. But it is
not now considered so essential to successful propagation as it was
formerly, and fully as good material may often be found in a common
sand-bank. Cuttings which strike strongly and vigorously may be placed
in a soil made of light garden loam with twice its bulk of sand added
to it. All soils used for in-door cuttage should be sifted or screened
before using to bring them to a uniform texture.
Hard-wood cuttings are commonly planted out-doors in mellow and light
loam, well trenched. Only fine and well-rotted manure should be applied
to the cutting bed, and it should be well mixed with the soil. In most
cases, a well-drained soil gives best results, but some cuttings root
and grow well in wet soils or even in standing water, as poplars,
willows, some of the dogwoods, plane-tree and others.
Bottom heat is always essential to the best success with cuttings.
In out-door work this is supplied by the natural heat of the soil in
spring and summer, and it is often intensified by burying hard-wooded
cuttings bottom end up for a time before planting them. This operation
of inverting cuttings is often practiced with grapes, particularly with
the Delaware and others which root with some difficulty. The cuttings
are tied in bundles and are buried in a sandy place, with the tops
down, the butts being covered two or three inches with sand. They may
be put in this position in the fall and allowed to remain until the
ground begins to freeze hard, or they may be buried in spring and
allowed to remain until May or June and then be regularly planted. In
out-door cuttage, the cuttings which are of medium length, from six to
eight inches, derive more bottom heat than the very long ones, such
as were formerly used for the propagation of the grape. In in-door
work bottom heat is obtained artificially. Cutting benches should
have abundant piping beneath, and in the case of many tropical and
sub-tropical species the bottom heat may be intensified by enclosing
the benches below so that no heat can escape into the house. Doors can
be placed in the partition alongside the walk to serve as ventilators
if the heat should become too intense. In all cuttings, bottom or root
growth should precede top growth, and this is aided by bottom heat.
[Illustration: Fig. 43. Grape cutting.]
As a rule, roots arise most readily from a joint, and it is therefore
a common practice to cut off the base of the cutting just below a
bud, as shown in the grape cutting, Fig. 43. Sometimes the cutting is
severed at its point of attachment to the parent branch, and a small
portion, or "heel," of that branch is allowed to remain on the cutting.
This heel may be nothing more than the curved and hardened base of the
cutting at its point of attachment, as in the cornus cutting, Fig. 44.
Sometimes an entire section of the parent branch is removed with the
cutting, as in the "mallet" cuttings of grapes, Fig. 45. Of course,
comparatively few heel or mallet cuttings can be made from a plant,
as only one cutting is obtained from a branch, and it is advisable,
therefore, to "cut to buds" rather than "cut to heels;" yet there are
many plants which demand a heel, if satisfactory results are to be
obtained. The requirements of the different species in this direction
can be learned only by experience, but it may be said that in general
the hardest or closest wooded plants require a heel or a joint at
the base. Willows, currants, basswoods, and others with like soft
wood, emit roots readily between the buds, yet even in these cases
propagators quite usually cut to buds.
[Illustration: Fig. 44. Heel cutting of Cornus.]
Wounds upon plants begin to heal by the formation of loose cellular
matter which gives rise to a mass of tissue known as a _callus_. This
tissue eventually covers the entire wound, if complete healing results.
As a rule, the first apparent change in a cutting is the formation of
a callus upon the lower end, and it is commonly supposed that this
process must be well progressed before roots can form. But roots do
not necessarily arise from the callus, and in many plants they appear
to bear no relation to it in position. In willows, for instance,
roots arise from the bark quite irregularly and at some distance from
the callus. Yet, as a matter of practice, best results are obtained
from callused cuttings, particularly if the cuttings are made from
mature wood, but this is probably due quite as much to the fact that
considerable time is required for the formation of the adventitious
buds which give rise to the roots as from any connection between the
callusing and rooting processes themselves. Hard-wood cuttings give
better results when kept dormant for some time after they are cut. They
are usually made in the fall, and stored during the winter in sand,
sawdust or moss in a cool cellar, or buried in a sandy and well-drained
place. This, at least, is the practice with hard-wood cuttings of
deciduous plants. Hard-wood evergreen cuttings, when taken in the fall,
are usually set at once, as their foliage will not allow them to be
buried with safety; but in this case, the cuttings are kept "quiet"
or dormant for a time, to allow callusing to progress. If cuttings
are buried so deep that they cannot sprout, callusing may be hastened
by placing them in a mild temperature. Single-eye grape cuttings are
sometimes packed between layers of sand in a barrel and the barrel is
set under a forcing-house bench where the temperature is about 50°.
Eight or ten inches of sand is usually placed over the top layer. In
this manner, cuttings which have been obtained in winter or spring can
be callused before planting time.
[Illustration: Fig. 45. Mallet cutting of grape.]
It is a singular fact that the lower end of the cutting, as it stood
upon the parent plant, produces roots and the upper end produces leaves
and shoots, even if the cutting is inverted. And if the cutting is
divided into several parts, each part will still exhibit this same
differentiation of function. This is true even of root-cuttings, and of
other cuttings which possess no buds. The reasons for this localization
of function are not yet clearly understood, although the phenomenon has
lately been the subject of study. Upon this fact depends the hastening
of the rooting process in inverted cuttings by the direct application
of heat to the bottoms, and it likewise indicates that care must be
taken to plant cuttings in approximately their natural direction if
straight and handsome plants are desired.
The particular method of making the cutting and the treatment to which
it should be subjected, must be determined for each species or genus.
Some plants, as many maples, can be propagated from wood two or three
years old, but in most cases the wood of the previous or present
season's growth is required. Nearly all soft and loose wooded plants
grow readily from hard-wood cuttings, while those with dense wood are
often multiplied more easily from soft or growing wood. Some plants,
as oaks and hickories, are propagated from cuttings of any description
only with great difficulty. It is probable, however, that all plants
can be multiplied by cuttings if properly treated. It often happens
that one or two species of a closely defined genus will propagate
readily from cuttings while the other species will not, so that the
propagator comes to learn by experience that different treatment is
profitable for very closely related plants. For instance, most of the
viburnums are propagated from layers in commercial establishments, but
_V. plicatum_ is grown extensively from cuttings.
=Particular Methods--Kinds of Cuttings.=--Cuttings are made from all
parts of the plant. In its lowest terms, cuttage is a division of the
plant itself into two or more nearly equal parts, as in the division
of crowns of rhubarb, dicentra, and most other plants which tend to
form broad masses or stools. This species of cuttage is at times
indistinguishable from separation, as in the dividing of lily bulbs
(page 25), and at other times it is essentially the same as layerage,
as in the dividing of stools which have arisen from suckers or layers.
This breaking or cutting up of the plants into two or more large parts
which are already rooted is technically known as _division_. It is
only necessary, in dividing plants, to see that one or more buds or
shoots remain upon the portions, and these portions are then treated in
the same manner as independent mature plants; or sometimes, when the
divisions are small and weak, they may be handled for a time in a frame
or forcing-house in the same manner as ordinary cuttings.
Cuttings proper may be divided into four general classes: 1, of tubers;
2, of roots and root-stocks; 3, of stems; 4, of leaves.
=1. Tuber Cuttings.=--Tubers are thickened portions of either roots
or stems, and tuber cuttings therefore fall logically under classes
2 and 3; but they are so unlike ordinary cuttings that a separate
classification is desirable. Tubers are stored with starch, which is
designed to support or supply the plant in time of need. Tuber cuttings
are therefore able to support themselves for a time if they are placed
in conditions suited to their vegetation. Roots rarely arise from the
tubers themselves, but from the base of the young shoots which spring
from them. This fact is familiarly illustrated in the cuttings of
Irish and sweet potatoes. The young sprouts can be removed and planted
separately and others will arise from the tuber to take their places.
This practice is employed sometimes with new or scarce varieties of the
Irish potato, and three or four crops of rooted sprouts can be obtained
from one tuber. The tuber is cut in two lengthwise and is then laid in
damp moss or loose earth with the cut surface down, and as soon as the
sprouts throw out roots sufficient to maintain them they are severed
and potted off. Sweet potatoes are nearly always propagated in this
manner.
In making tuber cuttings, at least one eye or bud is left to each
piece, if eyes are present; but in root-tubers, like the sweet potato,
there are no buds, and it is only necessary to leave upon each portion
a piece of the epidermis from which adventitious buds may develop. The
pseudo-bulbs of some orchids are treated in this manner, or the whole
bulb is sometimes planted. A shoot, usually termed an off-shoot, arises
from each pseudo-bulb or each piece of it, and this is potted off as an
independent plant. (See Orchids, in Chapter VI.)
Cuttings made from the ordinary stems of some tuberiferous plants will
produce tubers instead of plants. This is the case sometimes with the
potato. The cutting produces a small tuber near its lower extremity,
or sometimes in the axil of a leaf above ground, and this tuber must
be planted to secure a new plant. Leaf cuttings of some tuberiferous
or bulbiferous plants produce little tubers or bulbs in the same way.
Hyacinth leaves, inserted in sand in a frame, will soon produce little
bulblets at their base, and these can be removed and planted in the
same manner as the bulbels described in Chapter II.
[Illustration: Fig. 46. Root-cutting of Blackberry.]
Many tubers or tuber-like portions, which possess a very moist or soft
interior and a hard or close covering, vegetate more satisfactorily if
allowed to dry for a time before planting. The pseudo-bulbs of orchids,
crowns of pine-apples and cuttings of cactuses are examples. Portions
of cactuses and pine-apples are sometimes allowed to lie in the sun
from two to four weeks before planting. This treatment dissipates the
excessive moisture and induces the formation of adventitious buds.
[Illustration: Fig. 47. Root-cutting of Dracæna.]
=2. Root Cuttings.=--Many plants can be multiplied with ease by means
of short cuttings of the roots, particularly all species which posses
a natural tendency to "sucker" or send up sprouts from the root. All
root-stocks or underground stems can be made into cuttings. True root
cuttings possess no buds whatever; the buds develop after the cutting
is planted. Roots are cut into pieces from one to three inches long and
are planted horizontally in soil or moss. These cuttings thrive best
with bottom heat, but blackberries and some other plants, grow readily
with ordinary out-door treatment. A root-cutting of the blackberry is
shown in Fig. 46. (See Blackberry, in Chapter VI.) A growing dracæna
cutting is exhibited in Fig. 47. The cuttings of this plant are handled
in a propagating-frame or on a cutting bench in a warm greenhouse. The
bouvardias and many other plants can be grown in the same manner. Many
of the fruit-trees, as peach, cherry, apple and pear, can be grown
readily from these short root-cuttings in a frame. Variegation cannot
always be transmitted by root-cutting, _e. g._, _Symphytum asperrimum,
variegatum_. Among kitchen garden plants, the horse-radish is the most
familiar example of propagation by root-cuttings. The small side roots,
a fourth inch or so in diameter, are removed when the horse-radish is
dug in fall or spring, and are cut into four to six inch lengths, as
seen in Fig. 48. These cuttings are known as "sets" among gardeners.
(See Horse-radish, Chapter VI.) When the crowns of horse-radish are
cut and used for propagation, the operation falls strictly under
division, from the fact that buds or eyes are present; and the same
remark applies to rhubarb, which, however, is not propagated by true
root-cuttings.
[Illustration: Fig. 48. Horse-radish root-cuttings.]
=3. Stem Cuttings.=--Cuttings of the stem divide themselves into two
general classes: those known as cutting of the ripe, mature or hard
wood, and cuttings of the green, immature or soft wood. The two classes
run into each other; no hard and fast lines can be drawn.
_Hard-wood cuttings_ are made at any time from late summer to spring.
It is advisable to make them in the fall in order to allow them to
callus before the planting season, and to forestall injury which
might result to the parent plant from a severe winter. They may be
taken as early as August, or as soon as the wood is mature, and be
stripped of leaves. Callusing can then take place in time to allow
of fall planting. Or the cuttings taken in early fall may be planted
immediately and be allowed to callus where they stand. All fall cutting
beds should be mulched to prevent the heaving of the cuttings. As a
rule, however, hard-wood cuttings are buried on a sandy knoll or are
stored in moss, sand or sawdust in a cellar until spring. (See page 50.)
There is no general rule to govern the length of hard-wood cuttings.
Most propagators prefer to make them six to ten inches long, as this is
a convenient length to handle. Two buds are always to be taken, one bud
or one pair at the top and also at the bottom, but in "short-jointed"
plants more are obtained. Sometimes all but the top buds are removed
to prevent the appearance of too many shoots. Grape cuttings are now
commonly cut to two or three buds (Fig. 43), two being the favorite
number for most varieties. (See Grape, Chapter VI.) Currant and
gooseberry cuttings (Fig. 49) usually bear from six to ten buds. All
long hard-wood cuttings are set perpendicularly, or nearly so, and only
one or two buds are allowed to stand above the surface.
[Illustration: Fig. 49. Currant cutting.]
When the stock is rare, cuttings are made of single eyes or buds.
This is particularly the case with the grape (see Chapter VI), and
currants and many other plants are occasionally grown in the same
manner. Fig. 50 shows a single eye grape cutting. These cuttings,
whatever the species, are commonly started under glass with bottom
heat, either upon a cutting bench or in a hot-bed. The soil should be
kept uniformly moist, and when the leaves appear the plants should be
frequently sprinkled. In from thirty to forty days the plants are ready
to pot off. Single eye cuttings are usually started about three or
four months before the season is fit for out-door planting, or about
February in the northern states. The most advisable method of treatment
varies with the season and locality as well as with the species or
variety. It is well known, for instance, that the Delaware grape can
be propagated more easily in some regions than in others. A common
style of single eye cutting is made with the eye close to the top end,
and a naked base of an inch or two. This is inserted into the soil
perpendicularly, with the eye just above the surface. It is much used
for a variety of plants.
[Illustration: Fig. 50. Single-eye Grape cutting.]
Many coniferous plants are increased by cuttings on a large scale,
especially retinosporas, arbor-vitæs, and the like. Cuttings are made
of the mature wood, which is planted at once (in autumn) in sand under
cover, usually in a cool greenhouse. Most of the species root slowly
and they often remain in the original flats or benches a year, but
their treatment is usually simple. In some cases junipers, yews and
_Cryptomeria Japonica_ will not make roots for nearly twelve months,
keeping in good foliage however, and ultimately giving good plants.
(For more explicit directions, see Thuya and Retinospora in Chapter VI.)
Most remarkable instances of propagation by means of portions of stems
are on record. Chips from a tree trunk have been known to produce
plants, and the olive is readily increased by knots or excrescences
formed upon the trunks of old trees. These excrescences occur in many
plants and are known as _knaurs_. They are often abundant about the
base of large plane-trees. But they are not often used for purposes of
propagation. Whole trunks will sometimes grow after having been cut for
many months, especially of such plants as cactuses, many euphorbias
and yuccas. And sections of these spongy trunks will grow, also. Even
saw-logs of our common trees, as elm and ash, will sprout while in the
"boom," or water.
_Green-wood cuttings_ are more commonly employed than those from
the mature wood, as they "strike" more quickly, they can be handled
under glass in the winter, and more species can be propagated by them
than by hard-wood cuttings. "Slips" are green-wooded cuttings, but
the term is often restricted to designate those which are made by
pulling or "slipping" off a small side shoot. All soft-wooded plants
and many ornamental shrubs are increased by green cuttings. There
are two general classes of green-wood cuttings: those made from the
soft and still growing wood, and those made from the nearly ripened
green-wood, as in _Azalea Indica_, oleander, ficus, etc. House plants,
as geraniums, coleuses, carnations, fuchsias, and the like, are grown
from the soft young wood, and many harder-wooded plants are grown in
the same way. Sometimes truly hard wood is used, as in camellia.
[Illustration: Fig. 51. Tough and brittle wood.]
In making cuttings from soft and growing shoots, the first thing to
learn is the proper texture or age of shoot. A very soft and flabby
cutting does not grow readily, or if it does it is particularly liable
to damp-off, and it usually makes a weak plant. Too old wood is slow
to root, makes a poor plant and is handled with difficulty in many
species. The ordinary test for beginners is the manner in which the
shoot breaks. If, upon being bent, the shoot snaps off squarely so
as to hang together with only a bit of bark, as in the upper break
in Fig. 51, it is in the proper condition for cuttings; but if it
bends or simply crushes, as in the lower portion of the figure, it is
either too old or too young for good results. The tips of the shoots
of soft-wooded plants are usually employed, and all or a portion of
the leaves are allowed to remain. They are inserted in sharp sand
to a sufficient depth to hold them in place, and the atmosphere and
soil must be kept moist to prevent wilting or "flagging". The cuttings
should also be shaded for the first week or two. A propagating-frame
is often employed. Soft cuttings are commonly cut below a bud or
cut to a heel, but this is unnecessary in easily rooted plants like
geranium, coleus, heliotrope, etc. Fig. 52 shows an oleander cutting
at _a_, a carnation at _b_, and a geranium at _c_. A coleus cutting is
illustrated in Fig. 53. Sometimes the growth is so short or the stock
so scarce that the cutting cannot be made long enough to hold itself in
the soil. In such case a toothpick or splinter is tied to the cutting
to hold it erect, as in the cactus cutting, Fig. 54, or the geranium
cutting, Fig. 55. In the window garden, soft cuttings may be started
in a deep plate which is filled half or two-thirds full of sand and
is then filled to the brim with water, and not shaded; this method,
practiced on a larger scale, is sometimes useful during the hot summer
months. If bottom heat is desired, the plate may be set upon the back
part of the kitchen stove. Oleanders usually root best when mature
shoots are placed in bottles of water.
[Illustration: Fig. 52. Soft cuttings.]
[Illustration: Fig. 53. Coleus cutting.]
Cuttings from the nearly mature green-wood are employed for hard-wooded
trees and shrubs, as diervillas (weigela), roses, hydrangeas, lilacs,
etc. They are cut in essentially the same manner as the hard-wood
cuttings described on page 55. They are often taken in summer when the
buds have developed and the wood has about attained its growth. They
are cut to two to four or five buds and are planted an inch or two deep
in shaded frames. They are kept close for some days after setting,
and the tops are sprinkled frequently. Care must be taken not to set
them too deep; they are rarely put in over an inch, if the cutting
is six or seven inches long. "June stock cuttings" are sometimes
advantageously made; here the young shoots of hardy shrubs are taken,
when about two to three inches long, the leaves partly removed, and
they are planted under glass, precisely as the geranium is treated in
the autumn. Several weeks are required for rooting, but good plants are
obtained which, when wintered in a cold-frame, can be planted out in
beds the next spring. Great care must be given to shading and watering.
_Hydrangea paniculata_ var. _grandiflora_, and _Akebia quinata_ are
examples; or any deutzia or more easily handled plant of which stock is
scarce may be cited.
[Illustration: Fig. 54. Cactus cutting held by splinter.]
[Illustration: Fig. 55. Cutting held by toothpick.]
Part of the leaves are removed, as a rule, before the cuttings are set,
as shown in the rose cutting, Fig. 56, and the hydrangea cutting, Fig.
57. This is not essential, however, but it lessens evaporation and the
tendency to "flag" or wilt. In most species the top can be cut off the
cutting, as seen in Figs. 44 and 57, but in other cases it seriously
injures the cutting. Fig. 58 shows a weigela cutting from which the top
was clipped. An unusually large callus formed at the bottom, but the
leaves shrivelled and the cutting is dead. This frequently occurs in
what some nurserymen call "end growers," among which may be mentioned
weigelas (properly diervillas), the shrubby altheas, _Cercis Japonica_,
and such spireas as _S. cratægifolia_, _S. rotundifolia_ var. _alba_
and _S. Cantonensis_ (_S. Reevesii_ of the trade) var. _robusta_.
[Illustration: Fig. 56. Rose cutting.]
These hardened cuttings, about two inches long, are often made in the
winter from forced plants. This is particularly the case with roses
(which see in Chapter VI). Cuttings taken in February, in the north,
will be ready to transfer to borders or nursery beds when spring opens.
Stout, well-rooted stock-plants are used from which to obtain these
cuttings, and they are cut back when taken to the house in the fall
in order to induce a good growth. Many hardy shrubs can be easily
propagated in this way when the work is difficult in the open air, _e.
g._, _Spiræa Cantonensis_ (_S. Reevesii_ of the catalogues) and _S. Van
Houttii_. Stock plants of the soft species, like coleus, lantanas and
geraniums, are obtained in like manner.
[Illustration: Fig. 57. Hydrangea cutting.]
=4. Leaf Cuttings.=--Many thick and heavy leaves may be used as
cuttings. Leaf cuttings are most commonly employed in the showy-leaved
begonias, in succulents, and in gloxinias, but many plants can be
propagated by them. Even the cabbage can be made to grow from leaf
cuttings. The whole leaf may be used, as shown in Fig. 59. It is simply
laid upon moist sand in a frame and held down by splinters thrust
through the ribs. The wound made by the peg induces the formation of
roots and a young plant arises. A half dozen or more plants can be
obtained from one leaf. Some operators cut off the ribs, instead of
wounding them with a prick. Many gardeners prefer to divide the leaf
into two nearly equal parts, and then set each part, or the better one,
upright in the soil, the severed edge being covered. This is shown in
Fig. 60. Fewer plants--often only one--are obtained in this manner, but
they are strong.
[Illustration: Fig. 58. Clipped Weigela cutting.]
[Illustration: Fig. 60. A upright Begonia leaf cutting.]
When stock is scarce the leaf may be cut into several fan-shaped
pieces. The whole leaf may be divided into as many triangular portions
as can be obtained with a portion of the petiole, a strong rib, or vein
at the base; these inserted and treated like coleus cuttings will all
root and make good plants within a reasonable time, say six months.
This form of cutting should be two to three inches long by an inch or
inch and one-half wide. Ordinarily, in this style of leaf-cutting,
the petiole or stalk is cut off close to the leaf and the lower third
or fourth of the leaf is then cut off by a nearly straight cut across
the leaf. This somewhat triangular base is then cut into as many
wedge-shaped pieces as there are ribs in the leaf, each rib forming the
center of a cutting. The point of each cutting should contain a portion
of the petiole. The points of these triangular portions are inserted in
the soil a half inch or so, the cutting standing erect or nearly so.
Roots form at the base or point in the ordinary manner.
[Illustration: Fig. 59. Begonia leaf cutting.]
Leaf cuttings are handled in the same manner as soft stem-cuttings
so far as temperature and moisture are concerned. There are
comparatively few species in which they form the most available means
of multiplication. In some cases, variegation will not be reproduced by
the rooted leaf. This is true in the ivy-leaved geranium L'Elegante; a
good plant can be obtained, but it reverts to the plain-leaved type.
CHAPTER V.
GRAFTAGE.
=Graftage.=--The process or operation of grafting or budding, or the
state or condition of being grafted or budded.
=Grafting.=--The operation of inserting a bud or a cion in a stock.
It is commonly restricted to the operation of inserting cions of
two or more buds, in distinction from budding, or the operation of
inserting a single bud in the stock; but there are no essential
differences between the two operations.
=Stock.=--In graftage, a plant or part of a plant upon which a cion
or bud is set. A _free stock_ is a seedling, in distinction from a
grafted stock.
=Cion or Scion.=--A portion of a plant which is mechanically inserted
upon the same or another plant (stock) with the intention that it
shall grow.
GENERAL CONSIDERATIONS.--Graftage is rarely employed for the
propagation of the species, as seedage and cuttage are more expeditious
and cheaper. Its chief use is to perpetuate a variety which does not
reproduce itself from seeds and which cannot be economically grown from
cuttings.
Nearly all the named varieties of tree fruits and many of those of
ornamental trees and shrubs are perpetuated by means of graftage. In
some species which present no marked varieties, however, propagation
by seeds or cuttings is for various reasons so difficult or uncertain
that recourse must be had to graftage. This is particularly true in
many of the firs and spruces which do not produce seeds to any extent
in cultivation. In other cases graftage is performed for the purpose
of producing some radical change in the character or habit of the
plants, as in the dwarfing of pears by grafting them upon the quince,
the elevation of weeping tops by working them upon upright trunks, and
the acceleration of fruit-bearing by setting cions in old plants. It is
sometimes employed to aid the healing of wounds or to repair and fill
out broken tops. And it has been used to make infertile plants fertile,
by grafting in the missing sex in diœcious trees, or a variety with
more potent pollen as practiced in some of the native plums. All these
uses of graftage fall under three heads: 1. To perpetuate a variety.
2. To increase ease and speed of multiplication. 3. To produce some
radical change in nature or habit of cion or stock.
Probably all exogenous plants--those which possess a distinct bark and
pith--can be grafted. Plants must be more or less closely related to
each other to allow of successful graftage of the one upon the other.
What the affinities are in any case can be known only by experiment.
As a rule, plants of close botanical relationship, especially those
of the same genus, graft upon each other with more or less ease; yet
this relationship is by no means a safe guide. A plant will often
thrive better upon a species of another genus than upon a congener.
The pear, for instance, does better upon many thorns than upon the
apple. Sometimes plants of very distinct genera unite readily. Thus
among cacti the leafless epiphyllum grows remarkably well upon the
leaf-bearing pereskia. It should be borne in mind that union of tissues
is not a proof of affinity. Affinity can be measured only by the
thrift, healthfulness and longevity of the cion. The bean has been
known to make a union with the chrysanthemum, but it almost immediately
died. Soft tissues, in particular, often combine in plants which
possess no affinity whatever, as we commonly understand the term.
Neither does affinity refer to relative sizes or rates of growth of
stock and cion, although the term is sometimes used in this sense.
It cannot be said that some varieties of pear lack affinity for the
quince, and yet the pear cion grows much larger than the stock. In
fact, it is just this difference in size and rate of growth which
constitutes the value of the quince root for dwarfing the pear. When
there is a marked difference in rate of growth between the stock and
cion, an enlargement will occur in the course of time, either above or
below the union. If this occurs upon the stem, it makes an unsightly
tree. If the cion greatly outgrows the stock a weak tree is the result.
Graftage can be performed at almost any time of the year, but the
practice must be greatly varied to suit the season and other
conditions. The one essential point is to make sure that the cambium
layers, lying between the bark and wood, meet as nearly as possible
in the cion and stock. This cambium is always present in live parts,
forming woody substance from its inner surface and bark from its outer
surface. During the season of greatest growth it usually occurs as a
soft, mucilaginous and more or less unorganized substance, and in this
stage it most readily repairs and unites wounded surfaces. And for this
reason the grafting and budding of old trees are usually performed in
the spring. Later in the season, the cambium becomes firmer and more
differentiated, and union of woody parts is more uncertain. It is
also necessary to cover the wounds in order to check evaporation from
the tissues. In out-door work wax is commonly used for all species of
graftage which wound the wood itself, but in budding, the loosened
bark, bound down securely by a bandage, affords sufficient protection.
It is commonly supposed that an ordinary cleft-graft cannot live if
the bark of the stock immediately adjoining it is seriously wounded,
but the bark really serves little purpose beyond protection of the
tissues beneath. A cion will grow when the bark is entirely removed
from the stub if some adequate protection can be given which will not
interfere with the formation of new bark. The cion must always possess
at least one good bud. In most cases, only buds which are mature or
nearly so are used, but in the grafting of herbs very young buds may
be employed. These simple requirements can be satisfied in an almost
innumerable variety of ways. The cion or bud may be inserted in the
root, crown, trunk or any of the branches; it may be set under the bark
simply or inserted into the wood itself in almost any fashion; and the
operation may be performed either upon growing or dormant plants at any
season. But in practice there are comparatively few methods which are
sufficiently simple and expeditious to admit of general use.
Graftage may be divided into three general divisions, between which,
however, there are no decisive lines of separation: 1. Bud-grafting or
budding, in which a single bud is inserted upon the surface of the wood
of the stock. 2. Cion-grafting or grafting proper, in which a detached
twig bearing one or more buds is inserted into or upon the stock. 3.
Inarching or grafting by approach, in which the cion remains attached
to the parent plant until union takes place. Each of these divisions
can be almost endlessly varied and sub-divided, but in this discussion
only the leading practices can be detailed. The following enumeration,
after Baltet, will give a fair idea of the kinds of grafting which have
been employed under distinct names:
1. Bud-Grafting or Budding.
1.--Grafting with shield-buds.
Bud-grafting under the bark, or by inoculation.
" " ordinary method.
" " with a cross-shaped incision.
" " " the incision reversed.
" " by veneering.
Bud-grafting, the combined or double method.
2.--Flute-grafting.
" " common method.
" " with strips of bark.
2. Cion-Grafting or Grafting Proper.
1.--Side-grafting under the bark.
" " with a simple branch.
" " with a heeled branch.
" " in the alburnum.
" " with a straight cleft.
" " with an oblique cleft.
2.--Crown-grafting.
Ordinary method.
Improved method.
3.--Grafting _de precision_.
Veneering, common method.
" in crown-grafting.
" with strips of bark.
Crown-grafting by inlaying.
Side-grafting by inlaying.
4.--Cleft-grafting, common single.
Cleft-grafting, common double.
" " oblique.
" " terminal.
" " " woody.
" " " herbaceous.
5.--Whip-grafting, simple.
" " complex.
Saddle-grafting.
6.--Mixed-grafting.
Grafting with cuttings.
When the cion is a cutting.
When the stock is a cutting.
When both are cuttings.
Root-grafting of a plant on its own root.
" " " " the roots of another plant.
Grafting with fruit buds.
3. Inarching or Grafting by Approach.
1.--Method by veneering.
" " inlaying.
English method.
2.--Inarching with an eye.
" " a branch.
=Particular Methods.=--_Budding._ Budding is the operation of inserting
a single bud, bearing little or no wood, upon the surface of the stock.
The bud is nearly always inserted under the bark of the stock, but in
flute-budding a piece of bark is entirely removed and the bud is used
to cover the wound. There is no general rule to determine what species
of plants should be budded and which ones cion grafted. In fact, the
same species is often multiplied by both operations. Plants with thin
bark and an abundance of sap are likely to do best when grafted; or
if they are budded, the buds should be inserted at a season when the
sap is least abundant to prevent the "strangulation" or "throwing out"
of the bud. In such species the bark is not strong enough to hold the
bud firmly until it unites; and solid union does not take place until
the flow of sap lessens. Budding is largely employed upon nearly all
young fruit-trees, and almost universally so upon the stone-fruits. It
is also used in roses, and many ornamental trees. Budding is commonly
performed during the growing season, usually in late summer or early
fall, because mature buds can be procured at that time and young stocks
are then large enough to be worked readily. But budding can be done in
early spring, just as soon as the bark loosens; in this case perfectly
dormant buds must have been taken in winter. Budding is always best
performed when the bark slips or peels easily. It can be done when the
bark is tight, but the operation is then tedious and uncertain.
Shield-budding.--There is but one style of budding in general use in
this country. This is known as shield-budding, from the shield-like
shape of the portion of bark which is removed with the bud.
Technically, the entire severed portion, comprising both bark and bud,
is called a "bud." A shield bud is shown natural size in Fig. 61. This
is cut from a young twig of the present season's growth. It is inserted
underneath the bark of a young stock or branch, and is then securely
tied, as shown in Fig. 65.
[Illustration: Fig. 61. Shield-bud.]
The minor details of shield-budding differ with nearly every operator.
In commercial practice, it is performed in the north from early July
until the middle of September. In the southern states it usually begins
in June. As a rule, apples and pears are budded before peaches. This
is due to the fact that peach-stocks are nearly always budded the same
season the pits are planted, and the operation must be delayed until
the stocks are large enough to be worked. Most other fruit-stocks,
especially apples and pears, are not budded until two years after the
seeds are sown. The plants grow for the first season in a seed-bed.
The next spring they are transplanted into nursery rows, and budded
when they become large enough, which is usually the same year they are
transplanted. The nurseryman reckons the age of his stock from the time
of transplanting, and the age of the marketable tree from the time when
the buds or grafts begin to grow. The young stocks are "dressed" or
trimmed before being set into the nursery. This operation consists in
cutting off a fourth or third of the top and the tap root. This causes
the roots to spread and induces a vigorous growth of top because it
reduces the numbers of shoots; and such stocks are more expeditiously
handled than long and untrimmed ones.
Stocks should be at least three-eighths inch in diameter to be budded
with ease. Just before the buds are set, the leaves are removed
from the base of the stock so that they will not interfere with the
operation. They are usually rubbed off with the hand for a space of
five or six inches above the ground. They should not be removed more
than two or three days in advance of budding, else the growth of the
parts will be checked and the bark will set; any branches, too, as
in the quince, which might impede the work of the budder, are to be
cut off at the same time. The bud is inserted an inch or two above
the surface of the ground or as low down as the budder can work. The
advantage of setting the bud low is to bring the resulting crook or
union where it will not be seen. It is a common and good practice,
also, to place the bud upon the north side of the stock to shield it
from the sun.
[Illustration: Fig. 62. A stick of buds.]
The buds are taken from strong and well-hardened shoots of the season's
growth and of the desired variety. Usually the whole of the present
growth is cut, the leaves are removed, but a part of the petiole or
stalk of each leaf is left (as in Figs. 61 and 62) to serve as a handle
to the bud. This trimmed shoot is then called a "stick." A stick may
bear two dozen good buds when the growth has been strong, but only
ten or twelve buds are commonly secured. The upper buds, which are
commonly not fully grown and which are borne on soft wood, are usually
discarded. The buds are cut with a thin-bladed sharp knife. Various
styles of budding knives are in use, and the budder usually has decided
preferences for some particular pattern. The essentials of a good
budding-knife are these: the very best steel, a thin blade which has a
curved cutting end (as shown in Figs. 63 and 66), and lightness. The
curved end of the blade is used for making the incisions in the stock.
The handle of the budding-knife usually runs into a thin bone scalpel
at the end, and this portion is designed for the lifting or loosening
of the bark on the stock. Some budders, however, raise the bark with
the blade. A good form of blade, but one seldom made, has a rounded
end, the upper side of the curve being ground simply to a thin edge.
This blade may be used both for cutting the bark and loosening it,
thus overcoming the necessity of reversing the knife every time a bud
is set. If this form of blade were commonly known it would undoubtedly
soon come into favor. The blade of a common budding-knife can be ground
to this shape.
The bud is usually cut about an inch long. Most budders cut from below
upwards, but some prefer to make a downward incision. It does not
matter just how the bud is cut, if the surfaces are smooth and even
and the bud is not too thick. On a stick a fourth or three-eighths
inch through, the cut, at its deepest point just under the bud, is
about one-fourth the diameter of the twig. A bit of wood is therefore
removed with the bud, as shown in Fig. 61. There is some discussion
as to whether this wood should be left upon the bud, but no definite
experiments have been made to show that it is injurious to the
resulting tree. Some budders remove the wood with the point of the
knife or by a deft twist as the bud is removed from the stick. But
buds appear to live equally well with wood attached or removed. Some
propagators cut the buds as they go, while others prefer to cut a whole
stick before setting any, letting each bud hang by a bit of bark at the
top and which is cut off squarely when wanted, as shown in Fig. 62.
The wound or matrix which is to receive the bud is made by two
incisions, one vertical and one transverse (Fig. 63). These are light
cuts, extending only through the bark. The vertical slit is usually
made first and by the rounded end of the blade. This is an inch or
inch and a half long. The transverse cut is made across the top of
the vertical cut by one rocking motion of the blade towards the body.
The corners of the bark may be lifted a little by an outward motion
of the blade so as to allow the bud to be pushed in, but unless the
bark slips very freely it will have to be loosened by the end of the
blade or by the scalpel on the reverse end of the handle, as previously
described. The bud is now inserted in the cleft of the bark. It is
pushed down part way by the fingers, as in Fig. 64, but it is usually
driven home by pushing down upon the leaf-stalk handle with the back
of the knife-blade. The entire bud should pass into the cleft; or if a
portion of it should project above it should be cut off. If the bark
peels freely, the bud will slip in easily and will follow the cleft,
but if it sticks somewhat, more care is necessary to prevent the bud
from running out. If the bark is very tight, it may have to be loosened
with the knife throughout the length of the cleft; but budding should
be performed, if possible, when such pains are not necessary.
[Illustration: Fig. 63. Preparing the stock.]
The bud must now be tied. The whole matrix should be closed and bound
securely, as represented in Fig. 65. The dotted lines parallel with the
cleft show the extent to which the bud projects under the bark. The
string is usually started below the bud, the end being held by lapping
the second course over it, and the upper end being secured by drawing
a bow through under the upper course. Care should be taken not to bind
the string over the bud itself. The strings are previously cut the
required length--about a foot--and the tying is performed very quickly.
Any soft cord can be employed. Yarn and carpet warp are sometimes used.
The most common material, at least until the last few years, has been
bass matting. This is the inner bark of the bass-wood or linden. The
bark is stripped in early summer, and the inner portion is macerated
or "rotted" in water for four or five weeks. It is then removed, cut
into the desired lengths, and stripped into narrow bands--one-fourth to
one-half inch wide--when it may be sorted and stored away for future
use. If it is stiff and harsh when it comes from the maceration,
it should be pounded lightly or rubbed through the hands until it
becomes soft and pliable. The best tying material which we now have
is undoubtedly raffia. It is an imported article, coming from the
eastern tropics (the product of the palm _Raphia Ruffia_), but it is
so cheap that it will probably supersede even bass-bark. It is strong
and pliable, and is an excellent material for tying up plants in the
greenhouse, or small ones out-doors. The greatest disadvantage in its
use in the budding field is its habit of rolling when it becomes dry.
[Illustration: Fig. 64. Bud entering matrix.]
In two or three weeks after the bud is set it will have "stuck" or
united to the stock. The bandage must then be removed or cut. It is
the common practice to draw a budding-knife over the strings, on the
side opposite the bud, completely severing them and allowing them
to fall off as they will. If the strings are left on too long they
will constrict the stem and often kill the bud, and they also have a
tendency to cause the bud to "break" or begin to grow. The bud should
remain perfectly dormant until spring, for if it should begin to grow
it will be injured and perhaps killed by the winter. It should remain
green and fresh; if it shrivels and becomes brown, even though it
still adheres to the stock, it is worthless. Advantage can be taken,
when cutting the tyings, to rebud any stocks which have failed. If
the bud should begin to grow, because of a warm and wet fall or other
reasons, there is little remedy except perhaps to head the shoot back
if it should become long enough. If the stocks are protected by snow
during winter, some of the buds at the base of the shoot may pass the
cold in safety.
[Illustration: Fig. 65. The bud tied.]
The next spring the stock should be cut off just above the bud (Fig.
66), in order to throw the entire force of the plant into the bud. If
the root is strong and the soil good, the bud will grow two or three
feet the first year; or peaches and cherries will grow from two to
three times that height. All sprouts should be kept rubbed off the
stock, and the bud should be trained to a single stem. In some weak and
crooked growers, the new shoot must be tied, and some propagators in
such cases cut off the stock five or six inches above the bud and let
it serve as a stake to which to tie. The stock, of course, must not be
allowed to grow. Late in the season the stock is cut down close to the
bud, as in Fig. 66. Peaches and some other fruits are sold after having
made one season's growth from the bud, but pears, apples, and most
other trees are not often sold until the second or third year.
"June budding" is a term applied to the budding of stocks in early
summer while they are yet growing rapidly. It is employed mostly at
the south where the stocks can be grown to sufficient size by the last
of June or first of July. Small stocks are usually employed--those
ranging from one-fourth to one-third inch being preferred. A few strong
leaves should be left on the stock below the bud, and after the bud has
"stuck" the whole top should not be cut off at once, else the growing
plant will receive a too severe check. It is best to bend the top over
to check its growth or remove the leaves gradually. The bandages should
not be left on longer than six to ten days if the stock is growing
rapidly. To prevent the constriction of the stem, muslin bands are
sometimes used instead of bass or raffia. In hot and dry climates the
bud should be set an inch or two higher in June budding than in the
ordinary practice, to escape the great heat of the soil. June budding
is used upon the peach more than any other tree, although it can be
employed for any species which will give large enough stocks from seed
by the June following the sowing. In peaches, the bud will produce a
shoot from three to five feet high the same season the buds are set,
so that marketable budded trees can be produced in one season from the
seed.
[Illustration: Fig. 66. Cutting off the stock.]
A different kind of early summer budding is sometimes performed upon
apples and other fruit-trees. In this case the stocks are one or two
years old from the transplanting, and dormant buds are used. These
buds are cut the previous fall or winter in the same manner as cions,
and when spring approaches they are put on ice--in sawdust, sand or
moss--and kept until the stocks are large enough to receive them. The
particular advantage of this method is the distributing of the labor
of budding over a longer season, thereby avoiding the rush which often
occurs at the regular budding time.
Budders usually carry a number of "sticks" with them when they enter
the nursery. These may be carried in the pocket, or thrust into the
boot-leg; or some budders carry four or five sticks in the hand. The
budder follows a row throughout its length, passing over those trees
which are too small to work. It is a common practice to rest upon one
knee while budding, as shown in Fig. 67, but some prefer to use a low
stool. The tying is usually done by a boy, who should follow close
behind the budder in order that the buds shall not dry out. An expert
budder will set from 1,000 to 3,000 buds a day, in good stock, and with
a boy (or two of them for the latter speed) to tie. Peach stocks are
more rapidly budded than most others, as the bark is firm and slips
easily, and some remarkable records are made by skillful workmen.
[Illustration: Fig. 67. Budder at work.]
Budding is sometimes employed the same as top-grafting for changing
over the top of an old tree from one variety to another. The buds
cannot be easily inserted in very old and stiff bark, but in all smooth
and fresh bark they work readily. Sometimes old trees are severely
pruned the year before the budding is to be done, in order to obtain
young shoots in which to set the buds. In fruit-trees six or seven
years old or less, budding is fully as advantageous as grafting. New
varieties are also budded into old branches in order to hasten bearing
for the purpose of testing the variety. Here budding has a distinct
advantage over grafting, as it uses fewer buds, and the wood of new
sorts is often scarce.
Flute-Budding.--An occasional method of budding is that known under the
general name of flute-budding. In this method the bud is not covered by
the bark of the stock as in shield-budding. Fig. 68 illustrates it. A
portion of bark is removed entirely from the stock, and a similar piece
is fitted into its place. When the wound extends only part way about
the stem, as in the illustration, the operation is sometimes known as
veneer-budding. When it extends entirely around the stem it is called
ring or annular-budding. Flute-budding is usually performed late in
spring. It is best adapted to plants with very thick and heavy bark.
The bud is tied and afterwards treated in essentially the same manner
as in shield-budding.
[Illustration: Fig. 68. Flute-budding.]
A species of flute-budding in which a ring of bark is slipped down upon
the tip of a shoot, which has been girdled for the purpose, is called
whistle-budding or tubular-budding.
_Grafting._--Grafting is divided in various ways, but chiefly with
reference to the position of the union upon the plant and to the method
in which the scion and stock are joined. In reference to position,
there are four general classes: 1. Root-grafting, in which the stock is
entirely a root. 2. Crown-grafting, which is performed upon the crown
or collar of the plant just at the surface of the ground, an operation
which is often confounded with root-grafting. 3. Stem-grafting, in
which the cion is set on the trunk or body of the tree below the limbs,
a method occasionally employed with young trees. 4. Top-grafting, or
grafting in the branches of the tree. Any method of inserting the cion
may be employed in these classes. The best classification, particularly
for purposes of description, is that which considers methods of making
the union. Some of these kinds of grafting are catalogued on page 66.
For our purposes, we shall need to consider only the whip, saddle,
splice, veneer, cleft and bark-grafting.
Whip-Grafting.--Whip or tongue-grafting is employed only on small
stocks, usually upon those one or two years old. Both the cion and
stock are cut across diagonally, the cut surface extending from one
to two inches according to the size of the part. A vertical cleft is
then made in both, and the two are joined by shoving the tongue of
the cion into the cleft of the stock. The operation can be understood
by reference to Figs. 69, 70 and 71. Fig. 69 shows the end of a cion,
cut natural size. The stock is cut in the same manner, and the two
are joined in Figs. 70 and 71. The parts are held firmly by a bandage
passed five or six times around them. If the graft is to stand above
ground, the wound must be protected by applying wax over the bandage.
(Recipes for wax can be found at the end of this chapter.)
[Illustration: Fig. 69. Whip-graft.]
[Illustration: Fig. 70. Whip-graft in position.]
Root-grafting, especially of fruit-stocks, is performed almost entirely
by the whip-graft. This operation is performed in winter. The stocks,
either one or two years old, are dug and stored in the fall. In January
or February the grafting is begun. In true root-grafting, only pieces
of roots are used, but some prefer to use the whole root and graft at
the crown. In piece-root-grafting, from two to four trees are made from
a single root. A piece of root from two to four inches long is used,
as shown in Fig. 71. The parts are usually held by winding with waxed
string or waxed bands. The string should be strong enough to hold the
parts securely and yet weak enough to be broken without hurting the
hands. No. 18 knitting cotton answers this purpose admirably. It should
be bought in balls, which are allowed to stand for a few minutes in
melted wax. The wax soon saturates the ball. Waxed bands are made by
spreading melted wax over thin muslin, which is cut into narrow strips
when dry. The string is the more useful for rapid work. The grafts are
packed away in sand, moss or sawdust in a cool cellar until spring,
when the two parts will be firmly callused together. Some propagators
are now discarding all tying of root-grafts. The grafts are packed away
snugly, and if the storage cellar is cool--not above 40°--they will
knit together so that they can be planted without danger of breaking
apart. If the cellar is warm the grafts will start into growth and be
lost.
Cions are cut in fall or winter, or any time before the buds swell in
spring. Only the previous year's growth is used in all ordinary cases,
but in maples and some other trees older wood may be used. In the
grafting of peaches--which is very rarely done--the best cions are
supposed to be those which bear a small portion of two-year-old at the
lower end. This portion of old wood probably serves no other purpose
than a mechanical one, as the recent wood is soft and pithy. It is a
common opinion that cions are worthless if cut during freezing weather,
but this is unfounded. The cions are stored in sand, moss or sawdust in
a cool cellar, or they may be buried in a sandy place. Or sometimes,
when a few are wanted for top-grafting, they are thrust into the ground
beside the tree into which they are to be set the following spring.
Only well-formed and mature buds should be used. Sometimes flower-buds
are inserted for the purpose of fruiting a new or rare variety the
following year.
[Illustration: Fig. 71. Root-graft.]
In common root-grafting in the east and south, the cion bears about
three buds, and the root is about the same length, or perhaps shorter.
The variable and unknown character of these roots as regards hardiness,
renders it important in very severe climates that roots should be
obtained from the same plant as the cion, the hardiness of which is
known. It is, therefore, the practice in the prairie countries to use
a very long cion--eight inches to a foot--and to set it in the ground
to the top bud. The piece of root serves as a temporary support, and
roots are emitted along the cion. When the tree is ready for sale the
old piece of root is often removed, or sometimes it falls away of
itself. In this manner own-rooted trees are obtained, and it is for
this reason that root-grafting is more universally practiced west of
the Great Lakes than budding. Even cions of ordinary length often emit
roots, as seen in Fig. 72, but the cions are not long enough to reach
into uniformly moist soil. Some varieties of fruit-trees are found in
practice to root more readily than others.
[Illustration: Fig. 72. Growing Root-graft.]
There is much discussion as to the relative merits of budding and
root-grafting fruit-stocks, but the observations are usually so
indefinite or irrelevant that safe conclusions cannot be drawn
from them. We have seen that root-grafting serves an indispensable
purpose in the cold prairie regions by enabling nurserymen to secure
own-rooted trees of known hardiness. Aside from this it may be said
that root-grafting is cheaper than budding, as it is performed when
labor is cheap and two or more trees are made from one stock, Budded or
crown-grafted trees possess a greater root and usually make a stronger
growth, at least the first year or two, and it has been said that their
roots are more numerous and more symmetrically disposed. But there is
not yet a sufficient knowledge of the subject in all its details to
allow of dogmatic expressions upon it.
Saddle-Grafting.--Saddle-grafting is a simple and useful method for the
shoots of small, growing plants. The stock is cut to a wedge-shaped
end by two cuts, and the cion is split and set upon the wedge (Fig.
73). The union is then tied and waxed in the same way as exposed
whip-grafts. It is oftenest employed when a terminal bud is used, as
the wood in such cions is usually too weak to work well with a tongue.
[Illustration: Fig. 73. Saddle-graft.]
[Illustration: Fig. 74. Splice-grafting.]
Splice-Grafting.--The simplest form of grafting is that shown in Fig.
74, in which the two parts are simply cut across diagonally and laid
together. The parts are held only by the string, which, together
with the wax, is applied in the same way as upon the whip-graft.
Splice-grafting is frequently used upon soft or tender wood which will
not admit of splitting. It is adapted only to small shoots.
Veneer-Grafting.--Fig. 75 shows a style of grafting which is much
used, particularly for ornamentals and for rare stocks which are grown
in pots. An incision is made upon the stock just through the bark
and about an inch long (_A_, Fig. 75), the bit of bark being removed
by means of a downward sloping cut at its base. The base of the cion
is cut off obliquely, and upon the longest side a portion of bark is
removed, corresponding to the portion taken from the stock. The little
tongue of bark on the stock covers the base of the cion, when it is
set. The cion is tied tightly to the stock (_B_, Fig. 75), usually
with raffia. This method of grafting makes no incision into the wood,
and all the wounded surfaces are completely covered by the matching
of the cion and stock. It is not necessary, therefore, to wax over
the wounds, as a rule. The parts grow together quickly and uniformly,
making a solid and perfect union as shown at _D_, Fig. 75. So far as
the union of the parts is concerned, this is probably the ideal method
of grafting. This method, which is nothing but the side-graft of the
English gardeners with the most important condition of the longer
tongue on the stock, is known by various names, but it is oftenest
called veneer-grafting in this country.
[Illustration: Fig. 75. Veneer-grafting.]
Veneer-grafting is employed mostly from November to March upon potted
plants. Stocks which are grown out-doors are potted in the early fall
and carried in a cool house or pit. The cion is applied an inch or two
above the surface of the soil, and the stock need not be headed back
until the cion has united. (See Fig. 76.) Both dormant and growing
cions are used. All plants in full sap must be placed under a frame in
the house, in which they can be almost entirely buried with sphagnum,
not too wet, and the house must be kept cool and rather moist until
the cions are well established. Some species can be transferred to the
open border or to nursery rows in the spring, but most plants which are
grafted in this way are handled in pots during the following season.
Rhododendrons, Japanese maples and many conifers are some of the plants
which are multiplied by veneer-grafting. This method, when used with
hardy or tender plants, gives a great advantage in much experimental
work, because the stock is not at all injured by a failure and can
be used over again many times, perhaps even in the same season; the
manipulation is simple and easily acquired by inexperienced hands.
Cleft-Grafting.--In cleft-grafting the stock is cut off squarely
and split, and into the split a cion with a wedge-shaped base is
inserted. It is particularly adapted to large stocks and is the method
universally employed for top-grafting old trees. Fig. 77 represents
the operation. The end of the stock, technically called a "stub,"
is usually large enough to accommodate two cions, one upon either
side. In fact, it is better to use two cions, not only because they
double the chances of success but because they hasten the healing of
the stub. Cleft-grafting is at best a harsh process, especially upon
large limbs, and its evils should be mitigated as much as possible. In
common practice, the cion (Fig. 78) contains three buds, the lowest
one standing just above the wedge portion. This lowest bud is usually
entirely covered with wax, but it pushes through without difficulty. In
fact, being nearest the source of food and most protected, its chances
of living are greater than those of the higher buds. The sides of the
cion must be cut smoothly and evenly. A single draw cut on each side
with a sharp blade is much better than two or three partial cuts. A
good grafter makes a cion by three strokes of the knife, one to cut off
the cion and two to shape it. The outer edge of the wedge should be a
little thicker than the inner one so that the stock will bind upon it
and hold it firm at the point where the union first takes place. These
cions are taken in late fall or winter, and kept in the same manner as
directed for whip-grafting on pages 77 and 78.
[Illustration: Fig. 76. Veneer-graft.]
[Illustration: Fig. 77. Cleft-grafting.]
The stock or stub must be cut off squarely and smoothly with a sharp
and preferably fine-toothed saw. If one desires to be especially
careful in the operation, the end of the stub, or at least two opposite
sides of it, may be dressed off with a knife so that the juncture
between the bark and the wood may be more easily seen. Professional
grafters rarely resort to this practice, however. The stub is then
split to the depth of an inch and a half or two inches. Various styles
of "grafting-knife" are used to split the stub. The best one is that
shown in Fig. 79. It is commonly made from an old file by a blacksmith.
The blade is curved so that the bark of the stub is drawn in when the
knife is entering, thereby lessening the danger of loosening the bark.
Upon the end of the knife is a wedge, about four or five inches long,
for opening the cleft. The wedge is driven into the cleft and allowed
to remain while the cions are being placed. If the cleft does not open
wide enough to allow the cions to enter, the operator bears down on the
handle of the knife. The cions must be thrust down to the first bud, or
even deeper, and it is imperative that they fit tightly. The line of
separation between the bark and wood in the cion should meet as nearly
as possible the similar line in the stock. The cions are usually set a
trifle obliquely, the tops projecting outwards, to ensure the contact
of the cambium layers. Writers usually state that it is imperative to
success to have the exact lines between the bark and wood meet for
at least the greater part of their length, but this is an error. The
callus or connecting tissue spreads beyond its former limits when the
wounds begin to heal. The most essential points are rather to be sure
that the cion fits tightly throughout its whole length, and to protect
the wound completely with an air-tight covering.
[Illustration: Fig. 78. Cleft-graft cion.]
The wounds must now be covered with wax. Fig. 80 illustrates a stub
after the covering has been applied. If the grafting is done in early
spring when the weather is cold, the wax will have to be applied with
a brush. The wax is melted in a glue-pot, which is carried into the
tree. But if the weather is warm enough to soften the wax, it should
be applied with the hands. The hands are first greased to prevent the
wax from sticking. The two side or vertical portions are applied first.
The end of the mass of wax in the hand is flattened into a thin portion
about a half inch wide. This portion is then laid over the bud and held
there by the thumb of the other hand, while the wax is drawn downwards
over the cleft, being pressed down firmly upon the bark by the thumb
of the first hand. The wax gradually tails out until it breaks off
just below the lowest point of the cleft. The flattened upper part is
then wrapped around the cion upon either side, completely and tightly
encircling it. A simple deft wrapping of the wax about the cion makes
a tighter joint than can be secured in twice the time by any method of
pinching it into place. Another portion of wax is now flattened and
applied over the end of the stub. Many grafters apply a bit of wax to
the tops of the cion also. All the wounds must be covered securely.
[Illustration: Fig. 79. A cleft grafting-knife.]
[Illustration: Fig. 80. A waxed stub.]
The top-grafting of large trees is an important operation, and there
are many men who make it a business. These men usually charge by the
stub and warrant, the warrant meaning that one cion of the stub must
be alive when the counting is done late in summer. From two to three
cents a stub is a common price. A good grafter in good "setting" can
graft from 400 to 800 stubs a day and wax them himself. Much depends
upon the size of the trees, their shape, and the amount of pruning
which must be done before the grafter can work in them handily. Every
man who owns an orchard of any extent should be able to do his own
grafting. The most important factor in the top-grafting of an old
tree is the shaping of the top. The old top is to be removed during
three or four or five years and a new one is to be grown in its
place. If the tree is old, the original plan or shape of the top will
have to be followed in its general outlines. The branches should be
grafted, as a rule, where they do not exceed an inch and a half in
diameter, as cions do better in such branches, the wounds heal quickly
and the injury to the tree is less than when very large stubs are
used. The operator should endeavor to cut all the leading stubs at
approximately equal distances from the center of the tree. And then, to
prevent the occurrence of long and pole-like branches, various minor
side-branches should be grafted. These will serve to fill out the new
top and to afford footholds for pruners and pickers. Fig. 81 is a good
illustration of an old apple tree just top-grafted. Many stubs should
be set, and at least all the prominent branches should be grafted if
the tree has been well-trained. It is better to have too many stubs
and to be obliged to cut out some of them in after years, than to have
too few. In thick-topped trees, care must be exercised not to cut out
so much the first year that the inner branches will sunburn. All large
branches which must be sacrificed ought to be cut out when the grafting
is done, as they increase in diameter very rapidly after so much of
the top is removed. One horizontal branch lying directly over or under
another should not be grafted, for it is the habit of grafts to grow
upright rather than horizontally in the direction of the branch. It is
well to split all stubs on such branches horizontally, that one cion
may not stand directly under another.
[Illustration: Fig. 81. Top-grafted old tree.]
Top-grafting is performed in spring. The best time is when the leaves
are pushing out, as wounds made then heal quickly and cions are most
apt to live. But when a large amount of grafting must be done, it is
necessary to begin a month or even two before the leaves start. On the
other hand, the operation can be extended until a month or more after
the leaves are full-grown, but such late cions make a short growth,
which is likely to perish the following winter. Professional grafters
usually divide their men into three gangs, one to do the cutting of
the stubs, one to set the cions, and one to apply the wax. The cions
are all whittled before the grafter enters the tree. They are then
usually moistened by dipping into a pail of water and are carried in a
high side-pocket in the jacket. The handiest mallet is a simple club
or billy, a foot and a half long, hung over the wrist by a loose soft
cord (Fig 82). This is brought into the palm of the hand by a swinging
motion of the forearm. This mallet is always in place, never drops
from the tree, and is not in the way. The knife shown in Fig. 79 is
commonly used. A downward stroke of the mallet drives the knife into
the tree and an upward motion immediately following strikes the knife
on the outer end and removes it. Another downward motion drives in the
wedge. The sharpened nails and sticks commonly pictured as wedges in
cleft-grafting are useless for any serious work. And the common style
of grafting-knife sold by seedsmen, comprising a thin, broad blade set
in a heavy back piece, is also worthless. The blade is too thin to
split the stub. The various combined implements which have been devised
to facilitate cleft-grafting are usually impracticable in serious
operations. A very good grafting-knife for small stocks or trees in
nursery row is shown in Fig. 83. This is the Thomas knife. The larger
arm is made entirely of wood. At its upper end is a grooved portion
into which the blade closes. This blade can be made from the blade of a
steel case-knife, and it should be about two and a half inches long. It
is secured to an iron handle. The essential feature of this implement
is the draw cut which is secured by setting the blades and the pivot
in just the positions shown in the figure. The stock is cut off by the
shears, and the cleft is then made by turning the shears up and making
a vertical cut. The cleft is therefore cut instead of split, insuring a
tight fit of the cions. This tool is particularly useful upon hard and
crooked-grained stocks.
[Illustration: Fig. 82. Grafting-mallet.]
Cleft-grafting is often employed for other purposes than the
top-grafting of old trees. It is in common use on soft and fleshy
stocks, as cactuses, and various fleshy roots. Fig. 84 shows a
cleft-graft on cactus. The cion is held in place with a pin or cactus
spine, and it is then bound with raffia or other cord. Waxing is
not necessary. Fig. 85 illustrates a cleft root-graft of peony. The
cleft in the thick root is cut with a knife, and the stock is bound
up securely, usually with wire, as cord, unless waxed, rots off too
quickly. Wax is not used, as the graft is buried to the top bud. The
peony is grafted in summer. Dahlias are often grafted after the same
fashion, although some operators prefer, in such fleshy subjects, to
cut out a section from the side of the stock to receive the cion,
rather than to make a cleft. Hollyhocks, ipomœas, gloxinias and other
thick-rooted plants may be similarly treated.
Bark-grafting.--A style of grafting suited to large trees is shown in
Fig. 86. The stock is not cleft, but the cions are pushed down between
the bark and wood.
[Illustration: Fig. 83. Thomas' grafting-knife.]
[Illustration: Fig. 84. Cleft-graft of cactus.]
The cion must be cut very thin so that they will not break the bark
on the stock. Fig. 87 represents a good style of cion. It is cut to
a shoulder upon either side. Several cions can be placed in a single
stub, and as no splitting is necessary, it is a useful method for very
large limbs. It is especially useful in repairing trees when very
large branches are broken off. A dozen or more cions may be set about
the broken portion, after it is dressed off, and a few of them may
be allowed to remain after the wound has been healed. Bark-grafting
can be performed to advantage only when the bark peels readily. The
cions should be held in place by a tight bandage, as seen in Fig. 86,
and then wax should be applied in essentially the same manner as for
cleft-grafting. (See Fig. 80.) This is sometimes called crown-grafting,
and is useful under certain conditions.
A special form of bark-grafting is sometimes employed for covering
girdles about the base of an old tree, made by mice, gophers or
rabbits. The edges of the bark are trimmed, and cions are cut a couple
inches longer than the width of the girdle. These are sharpened at
both ends. One end is inserted under the bark below the girdle and the
other above it. The cions are placed close together entirely around the
tree. This operation is said to be necessary to keep up the connection
between the root and the top, but this is in most cases an error. A
good dressing of cow-dung, wax or clay, held on with stout bandages, is
much better than the grafting. This method of grafting is sometimes,
but erroneously, called inarching. A complete girdle made during the
spring or early summer will usually heal over readily if it is well
bandaged; and in some cases even the bandage is not necessary.
[Illustration: Fig. 85. Peony root-graft.]
Herbaceous-grafting.--In the preceding pages, the discussions have had
to do with cions which are dormant or at least well-hardened, and with
stocks which contain more or less hard woody substance. But herbaceous
shoots can be grafted with ease. All such plants as geraniums,
begonias, coleuses and chrysanthemums can be made to bear two or more
varieties upon the same individual. Almost any style of grafting can be
employed, but the veneer, cleft and saddle-grafts are preferred. Shoots
should be chosen for stocks which are rather firm, or in the condition
for making good cuttings. The cions should be in a similar condition,
and they may be taken from the tips of branches or made of a section
of a branch. The union should be bound snugly with raffia, and the
plant set in a propagating frame, where it must be kept close for a few
days. It is not necessary, in most cases, to use wax, and upon some
tender stocks the wax is injurious. Moss may be bound about the graft,
but unless the union is first thoroughly covered by the bandage, roots
will start into the moss and the parts will fail to unite. The growing
shoots of shrubs and trees can also be grafted, but the operation is
rarely employed. In various coniferous trees (as pines and spruces) the
young shoots are sometimes cleft or saddle-grafted in May, the parts
being well bandaged with waxed muslin or raffia, and shaded with paper
bags. The walnut and some other trees which do not work readily are
sometimes treated in this manner.
[Illustration: Fig. 86. Bark-grafting.]
A little known species of herbaceous-grafting is the joining of parts
of fruits. It is easily performed upon all fleshy fruits like tomatoes,
apples, squashes and cucumbers. When the fruit is half or more grown,
one-half is cut away and a similar half from another fruit is applied.
Better results follow if the severed side of the parent or stock fruit
is hollowed out a little, so as to let the foreign piece set into
the cavity. The edges of the epidermis of the stock are then tied up
closely against the cion by means of bass or raffia. The two parts are
securely tied together, but no wax is required. This operation succeeds
best under glass, where conditions are uniform and winds do not blow
the fruits about.
Even leaves may be used as stocks or cions. Any such succulent and
permanent leaves as those of the house-leeks, crassula, and the like
may have young shoots worked upon them, and leaves which are used as
cuttings can often be made to grow on other plants.
Seed-grafting.--A novel kind of grafting has been described in France
by Pieron, which consists in using a seed as a cion. This has been
used upon the grape. A seed is dropped into a gimlet-hole made near
the base of the vine while the sap is flowing in the spring. The seed
germinates, and after a time the plantlet unites with the stock.
[Illustration: Fig. 87. Cion for bark-grafting]
Double-grafting.--Grafting upon a grafted tree is known as
double-grafting or double-working. It is employed for the purpose of
growing a variety upon an uncongenial root or of securing a straight
and vigorous stock for a weak and poor grower. Some sorts of pears do
not unite well with the quince, and if it is desired to secure dwarfs
of these varieties, some variety which unites readily with the quince
must first be put upon it. The Angouleme takes well to the quince, and
upon Angouleme dwarfs the Seckel and some other varieties are often
worked. The last cion is usually set after the first one has grown one
season, although both may be set at the same time. Double-grafting
for the purpose of securing a better growth is often practiced. The
Canada Red apple, for instance, is such a poor grower that it is often
stem-worked or top-worked upon the Northern Spy or some other strong
stock. The Winter Nelis and the Josephine de Malines pears are often
double-worked for the same reason.
Cutting-grafting.--Cuttage and graftage are combined in various ways.
Cuttings of plants which root with difficulty are sometimes grafted
upon those which root easily. When the plants are transplanted, the
following autumn or spring, the nurse or stock can be removed, the
cion having taken root. Root-grafting with a long cion, described on
a previous page (78), is virtually a grafting of cuttings. In other
cases, union with an uncongenial stock is facilitated by allowing the
cion to project downwards beyond the point of union and to stand in
the soil or moss or a dish of water. Fig. 88 is a good illustration
of the practice. The cion extends into the soil nearly as far as the
root itself. After union has taken place, the lower part of the cion
is removed. This method can be used for some magnolias, mulberries,
birches, and many other plants of which some kinds root with more or
less difficulty. Bottle-grafting, described in most of the books, is
essentially this method, modified by letting the end of the cion drop
into a bottle of water. Sometimes a portion of the bandage is allowed
to hang in water, to keep the cion fresh until the parts join.
[Illustration: Fig. 88. Cutting-grafting.]
=Inarching.=--Inarching or grafting by approach is the process of
grafting contiguous plants or branches while the parts are both
attached to their own roots. When the parts are united, one of them is
severed from its root. Fig. 89 explains the operation. In this case,
the larger plant is designed for the stock. When the smaller plant has
united, it is cut off just below the union and it thenceforth grows
upon the other plant. Limbs of contiguous trees are sometimes grafted
in this way. It is the process employed by nature in what is called
natural grafting. Grape-vines are often inarched. A thrifty young
branch may be inarched into the stem of a fruit upon the same tree,
thus supplying the fruit with additional food and causing it to grow
larger than it might if undisturbed.
To join the parts, it is only necessary to remove the barks between
the stock and cion and then tie the two together snugly. If out-doors,
the junction should be waxed over; and it is then necessary, also, to
secure the branches in such manner that the wind cannot loosen them.
The parts are sometimes joined by a tongue, after the manner of a
whip-graft, but this is rarely necessary. Oranges and camelias were
often propagated by inarching in the old practice, but this work is now
much more easily done by the veneer-graft.
=Grafting-waxes.=--There are great numbers of recipes for waxes or
mastics for protecting grafts and covering wounds upon trees. In this
country the resin and beeswax waxes are most used, although some of the
alcoholic waxes are popular in some regions. In Europe, many clay and
pitch waxes are in common use. For most purposes, the wax No. 1 in the
following list will be found one of the best, especially for applying
by the hand. In making the resin and beeswax waxes, the materials are
first broken up finely and melted together. When thoroughly melted,
the liquid is poured into a pail or tub of cold water. It soon becomes
hard enough to handle, and it is then pulled and worked over until it
becomes tough or "gets a grain," at which stage it becomes the color
of very light-colored manilla paper. When wax is applied by hand, the
hands must be well greased. Hard tallow is the best material for this
purpose. In top-grafting large trees it is well to carry a supply of
tallow when waxing by smearing the backs of the hands before entering
the tree.
[Illustration: Fig. 89. Inarching.]
_1. Common Resin and Beeswax Waxes._
1. Resin, 4 parts by weight; beeswax, 2 parts; tallow, 1 part.
2. Resin, 4 lbs.; beeswax, 1 lb.; tallow, 1 lb.
3. Resin, 6 lbs.; beeswax, 2 lbs.; linseed oil, 1 pt.
4. Resin, 6 lbs.; beeswax, 1 lb.; linseed oil, 1 pt.; apply hot
with a brush, one-eighth of an inch thick over all the joints.
5. Resin, 4 lbs.; beeswax, 1 lb.; and from half to a pint
of raw linseed oil; melt all together gradually, and turn into
water and pull. The linseed oil should be entirely free from
cotton-seed oil. For use in warm weather.
6. Resin, 6 parts; beeswax, 1 part; tallow, 1 part. To be
used warm, in the house.
7. Resin, 4 or 5 parts; beeswax, 1-1/2 to 2 parts; linseed oil,
1 to 1-1/2 parts. For out-door work.
_2. Alcoholic Waxes._
8. Lefort's Liquid Grafting Wax, or Alcoholic Plastic.--Best
white resin, 1 lb.; beef tallow, 1 oz.; remove from the fire
and add 8 ozs. of alcohol. Keep in closed bottles or cans.
9. Alcoholic Plastic with Beeswax.--Melt 6 parts white resin
with 1 part beeswax; remove from stove and partially cool by
stirring, then add gradually--with continued stirring--enough
alcohol to make the mixture, when cool, of the consistency of
porridge. In the temperature of the grafting-room it will
remain sufficiently plastic to permit applying to the cut
surfaces with the finger.
10. Alcoholic Plastic with Turpentine.--Best white resin,
1 lb.; beef tallow, 1 oz.; turpentine, 1 teaspoonful; add enough
alcohol (13 to 15 fluid ozs. of 95 per cent. alcohol) to make the
wax of the consistency of honey. Or, less alcohol may be
added if the wax is to be used with the fingers.
_3. French and Pitch Waxes._
11. Common French.--Pitch, 1/2 lb.; beeswax, 1/2 lb.; cow-dung,
1 lb. Boil together, melt and apply with a brush.
12. Common French Bandage Wax.--Equal parts of beeswax,
turpentine and resin. While warm spread on strips of
coarse cotton or strong paper.
13. Grafting Clay.--1/3 cow-dung, free from straw, and 2/3
clay, or clayey loam, with a little hair, like that used in plaster,
to prevent its cracking. Beat and temper it for two or three
days until it is thoroughly incorporated. When used it should
be of such a consistency as to be easily put on and shaped with
the hands.
14. Resin, 2 lbs. 12 ozs.; Burgundy pitch, 1 lb. 11 ozs. At
the same time, melt 9 ozs. of tallow; pour the latter into the
former, while both are hot, and stir the mixture thoroughly.
Then add 18 ozs. of red ochre, dropping it in gradually and stirring
the mixture at the same time.
15. Black pitch, 28 parts; Burgundy pitch, 28 parts; beeswax,
16 parts; grease, 14 parts; yellow ochre, 14 parts.
16. Black pitch, 28 lbs.; Burgundy pitch, 28 lbs.; yellow
wax, 16 lbs.; suet or tallow, 14 lbs.; sifted ashes, 14 lbs.
When used, warm sufficiently to make it liquid, without being
so hot as to injure the texture of the branches.
17. Melt together 1-1/4 lb. of clear resin and 3/4 lb. of white
pitch. At the same time melt 1/4 lb. of tallow. Pour the
melted tallow into the first mixture, and stir vigorously. Then
before the stuff cools add, slowly stirring meantime, 1/2 lb.
of Venetian red. This may be used warm or cold.
_4. Waxed String and Bandage._
18. Waxed String for Root-grafting.--Into a kettle of melted
wax place balls of No. 18 knitting cotton. Turn the balls
frequently, and in five minutes they will be thoroughly saturated,
when they are dried and put away for future use. This material
is strong enough, and at the same time breaks so easily as not to
injure the hands. Any of the resin and beeswax waxes may be
used. When the string is used, it should be warm enough to
stick without tying.
19. Waxed Cloth.--Old calico or thin muslin is rolled on
a stick and placed in melted wax. When saturated it is allowed
to cool by being unrolled on a bench. It is then cut in strips
to suit. Or the wax may be spread upon the cloth with a brush.
_5. Waxes for Wounds._
20. Any of the more adhesive grafting waxes are excellent for
dressing wounds, although most of them cleave off after the
first year. Stiff and ochreous paints are also good.
21. Coal-tar.--Apply a coating of coal-tar to the wound, which
has first been pared and smoothed. If the wound contains a
hole, plug it with seasoned wood.
22. Hoskins' Wax.--Boil pine tar slowly for three or four
hours; add 1/2 lb. of beeswax to a quart of the tar. Have
ready some dry and finely sifted clay, and when the mixture of
tar and wax is partially cold, stir into the above named quantity
about 12 ozs. of the clay; continue the stirring until the mixture
is so stiff, and so nearly cool, that the clay will not settle. This
is soft enough in mild weather to be easily applied with a knife
or spatula.
23. Schæfell's Healing Paint.--Boil linseed oil (free from
cotton-seed oil) one hour, with an oz. of litharge to each pt. of
oil; then stir in sifted wood ashes until the paint is of the
proper consistency. Pare the bark until smooth. Paint the
wound over in dry weather, and if the wound is very large, cover
with a gunny-sack.
24. Tar for Bleeding in Vines.--Add to tar about 3 or 4
times its weight of powdered slate or some similar substance.
Apply with an old knife or flat stick.
25. Hot Iron for Bleeding in Vines.--Apply a hot iron to the
bare surface until it is charred, and then rub into the charred
surface a paste made of newly-burnt lime and grease.
26. Collodion for Bleeding in Vines.--It may be applied with
a feather or small brush. In some extreme cases two or three
coats will be needed, in which case allow the collodion to form
a film before applying another coat. Pharmaceutical collodion
is better than photographic.
CHAPTER VI.
THE NURSERY LIST.
=Aaron's Beard.= See Hypericum.
=Aaron's Rod.= See Verbascum.
=Abelia.= _Caprifoliaceæ._
In spring by layers under a frame, and in summer by
cuttings.
=Abies= (Fir, Spruce). _Coniferæ._
Propagated by seeds, which are usually kept dry over
winter and sown in spring in frames or in protected borders.
Cones should be fully matured before being gathered. If
they hold the seeds tightly they should be placed in a dry
place, sometimes even in an oven, until the scales spread.
In order to obtain stocky plants, the seedlings should be
transplanted the following spring. The named varieties and
the species which do not produce sufficient seed are winter-worked
upon seedling stocks which are potted from the seed-beds
in the fall. One-year-old stocks are commonly used,
but in some cases the requisite size is not reached until the
second year. Any of the common operations of grafting
may be employed. The conifers are not difficult to graft.
The European silver fir (_Abies pectinata_) may be used as a
stock, but the common Norway spruce is now the most
popular stock for species of both Abies and Picea.
=Abobra.= _Cucurbitaceæ._
Propagated by seeds, or rarely by soft cuttings.
=Abroma.= _Sterculiaceæ._
By seeds sown in March. By cuttings made in spring
from half-ripened wood, and placed under a bell-glass.
=Abronia= (Sand Verbena). _Nyctaginaceæ._
Propagated by seeds sown in autumn or spring, after the
outer skin has been peeled off. Sow in pots of sandy soil,
and keep in a frame until the following spring; then place in
their flowering quarters. By young cuttings, set in spring,
in sandy soil.
=Abrus.= _Leguminosæ._
Propagated by seeds raised in heat or by cuttings under
a hand-glass, in sand.
=Abuta.= _Menispermaceæ._
Propagated by cuttings planted in a pot of sand, with a
hand-glass placed over them, in heat.
=Abutilon.= _Malvaceæ._
Sow seeds in pans, with same soil and temperature as for
cuttings. By cuttings from young wood, at almost any
season; the best time, however, is spring or fall. Insert
in pots, in a compost of equal parts peat, leaf-mould, loam
and sand, and place in a temperature of 65° to 75°.
=Acacia.= _Leguminosæ._
Propagate by seeds sown as soon as ripe, in sandy peat;
about one-fourth inch deep, or a little more for large
seeds. Soak in hot water 24 hours if seeds are not fresh.
Keep temperature about 55° or 60° and pot off when large
enough to handle. By cuttings of the half-ripened wood,
put in with a heel, in equal parts peat and sand, covered
with pure sand. Insert the cuttings as soon as made; water,
and leave them in the shade till dry. Place under a bell-glass,
shade and water to prevent flagging. Pot off when
rooted and keep in a close pit or house until the plants are
thoroughly established. _A. pubescens_ and some others strike
readily from root-cuttings.
=Acæna.= _Rosaceæ._
Propagated by seeds, divisions, creeping rootlets and
cuttings.
=Acalypha.= _Euphorbiaceæ._
Propagated by cuttings in sandy soil under a glass, in stove
heat, during late winter or in spring.
=Acanthephippium.= _Orchideæ._
Propagated by dividing the pseudo-bulbs as soon as
growth commences. (See under Orchids.)
=Acantholimon.= _Plantagineæ._
Propagated by seeds sown carefully on a warm but rather
shaded border; by very carefully made divisions; and by
cuttings made in late summer and placed in frames to remain
during the winter.
=Acanthophœnix.= _Palmæ._
Propagated by seeds, sown in a moist bottom heat, in
a well decomposed compost of one part loam, one of peat,
one of leaf-mould, and one of sand.
=Acanthorhiza.= _Palmæ._
Propagated by seeds in a moist hot-bed in spring.
=Acanthostachyum.= _Bromeliaceæ._
Propagated by suckers, which strike readily in bottom
heat.
=Acanthus= (Bear's Breech). _Acanthaceæ._
Propagated by seeds sown in gentle heat, or by division of
the root in autumn or early spring. Also by root-cuttings.
Water carefully.
=Acer= (Maple). _Sapindaceæ._
Stocks are grown from stratified seeds, which should be
sown an inch or two deep. Some species, as _A. dasycarpum_,
come readily if seeds are simply sown as soon as ripe.
Varieties are often layered, but better plants are obtained by
grafting. The Japanese sorts are winter-worked on imported
_A. polymorphum_ stocks, either by whip or veneer grafting.
Varieties of native species are worked upon common native
stocks. Maples can also be budded in summer, and they
grow from cuttings of soft and ripe wood.
=Aceras.= _Orchideæ._
Propagated by carefully made divisions of the tubers.
(See under Orchids.)
=Aceratium.= _Tiliaceæ._
Propagated by ripe cuttings, which root readily in sand,
in heat, under a hand-glass.
=Achania.= See Malvaviscus.
=Achillea.= Including Ptarmica (Milfoil), _Compositæ_.
Propagated by seeds, root divisions and cuttings, during
spring.
=Achimenes=, including Scheeria. _Gesneraceæ._
Propagated by seeds, carefully sown in well-drained pans,
which are filled nearly to the rim, levelled, and well watered
with a fine rose. Sow seed and cover lightly with sand, and
place in shady position. Keep moist and apply water very
lightly. Place a sheet of glass over the seed-pan. After
large enough to be pricked off, treat like rooted cuttings.
The best time for all modes of grafting is early spring. By
scales from the corms, carefully rubbed off and sown like
seeds, in pots or pans of the same compost, barely covered
with sand, and placed in bottom heat. By leaves, severed
from the stems, and pricked into pots of similar soil to the
cuttings, placing all the petiole below the surface, and placed
in bottom heat. By cuttings from any portion of the stem;
insert in a soil of equal parts of peat and sand, in well-drained
pots, and place in bottom heat.
=Achras.= See Sapota.
=Achyranthes.= See Iresine.
=Achyronia.= See Priestleya.
=Aciphylla.= _Umbelliferæ._
Propagated in spring by seeds or divisions.
=Acis.= See Leucoium.
=Acisanthera.= _Melastomaceæ._
Increased by cuttings, which root freely in a mixture of
loam, sand and peat, in stove temperature.
=Acmadenia.= _Rutaceæ._
Increased by cuttings pricked in a pot of very sandy soil,
covered with a bell-glass.
=Acmena.= _Myrtaceæ._
Propagated by placing half-ripened cuttings in sand under
a glass without heat.