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mercial fertilizers, the material and quantities suggested for
the experiment are suitable for the average soil.



PRUNING AND TRAINING OF GRAPES



GENERAL CONSIDERATIONS

34, Pruning and training of the vines are perhaps the
most complex operations having to do with grape culture.
So many systems are in vogue for these operations that an
inexperienced person may easily become confused. However,
if one typical system in each general class is thoroughly mas-
tered the others in the class should not be diflScult.

35. Purposes of Pruning and Training. — Grapes are
pruned and trained for a ntmiber of purposes. They are pruned
to maintain the vigor of the vines, to obtain good size and



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§ 14 GRAPE CULTURE 29

quality in the fruit, to prevent overbearing, and to keep the
vines within proper boimds so that they will occupy a minimiun
area of groimd and not be in the way of vineyard operations.
Grapes are trained particularly for the purpose of keeping the
vines in manageable shape.

36. Time for Pruning. — ^The time for pruning grapes
extends from the dropping of the leaves in the fall to just before
the swelling of the buds in the spring. Some vineyardists
prune in the spring after a vigorous flow of sap has begun,
and daim that no serious injtiry results, but the so-called bleed-
ing of the vines that follows late pruning is no doubt devital-
izing to the plants. There is considerable sap flow in a vine
even before weather conditions appear favorable for it, so that
it is best not to delay pruning until vegetation starts in the
spring.

In sections where it is necessary, in order to prevent freezing,
to cover the vines in position or to lay them on the groimd for
covering, pruning is done before the vines are covered. In
this case it is advisable to leave more wood than is actually
needed for the next year's crop, as there is danger of some of
the buds being broken off or the canes being injured by the
covering and uncovering.

It is seldom advisable to prune vines when they are frozen,
as frozen canes are brittle and easily broken during handling.
Except for this, there is no reason why pruning should not be
done at any time dtuing the dormant season.

37. Definition of Terms- — Unfortunately, the nomen-
clature pertaining to vine pruning and training is not imiform
throughout the coimtry. This applies particularly to the terms
used to designate different parts of ti vine, and makes it some-
what difficult to describe the operations of pruning and train-
ing so that they will be readily understood in all sections.
In the following explanation of pruning and training systems,
the nomenclature advocated and used by Prof. U. P. Hedrick,
of the New York Agricultural Experiment Station, and Prof. L.
H. Bailey, of Cornell University, noted viticultural authorities,



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30 GRAPE CULTURE §14

will be used. No doubt this nomenclattu'e is as much in accord
with common usage, or more so, than any other.

In order that the nomenclature just referred to may be
understood, the principal terms will be defined. These terms
are: trunk, arm, spur, cane, and shoot. By trunk is meant the
body of a vine when 2 years old or more. In Fig. 9 the trunk
is shown at a. An ainn is a branch from the trunk that is
2 years old or more. Arms are shown in the illustration at h.
A spur is a very short division of an arm or of the trunk,
annually lengthening unless cut back, from which cane renewals




Pig. 9



are made. In the illustration, spurs are shown at c. A can«
is a 1-year-old branch of an arm or the trunk. Canes are
shown in the illustration at d. A shoot is a growing; 1^^
branch of the current season's growth.

38. Relation of Wood Growth to Fruit Bearing.

No matter what method of pruning and training is adopted,
a grower must keep in mind the relationship of wood growtn
to fruit bearing. Grapes are borne on the base of shoots oi
the current year's growth that spring from canes of the pre-
ceding year's growth. As an example of how knowledge of tius



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§ 14 GRAPE CULTURE SI

fact should be applied in pruning, the following specific case is
given: The average )deld for a Concord grape vine is about
15 pounds of fruit. In order for a vine to produce this yield,
from forty to sixty clusters of grapes are required. As each
shoot bears from two to three clusters, usually two, from twenty
to thirty buds must be left on the canes of the previous year's
growth to furnish the required number of clusters. These
buds might be left on a single cane, but usually two, three, or
more canes that are variously distributed on one or two main
arms, depending on the system of pruning and training adopted,
are selected to be retained. Good pruning, then, consists of
removing all wood except canes or spurs suflBcient to fiunish
the shoots necessary for the desired ntunber of clusters.



PRUNING AND TRAINING SYSTEMS

39. Pruning is more important than the training of vines
to any particular system; but there necessarily exists a relation-
ship between pruning and training. When the conditions of
a vine permit, it may be pruned for training to a definite sys-
tem, but, in many instances, the vigor of a vine, as shown by
the wood produced, will not permit the pruning necessary to
train it to a desired system. Hence, pruning and training are
largely matters to be governed by individual judgment. A
vineyardist should decide how much pruning each vine in his
vineyard should receive and then choose a system of training
by which the wood can be handled to the best advantage.
If the vines are in a vigorous condition, the system of training
to be adopted is, of course, somewhat optional with the grower;
although there is no doubt that certain varieties do best when
trained in a particular way. For example, it is generally
agreed that strong-growing varieties such as the Concord and
the Niagara do best when trained with the shoots drooping;
and that weaker, slower-growing varieties such as the Delaware
do best when trained with the shoots upright, other conditions
being the same in each case.

40. Drooping Systems. — In the so-called drooping sys-
tems of priming and training the shoots are allowed to droop

249—17



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32



GRAPE CULTURE



§14



and hang free, not being tied. These systems have the advan-
tage of being economical, as no summer tying is necessary,
and the clusters hang in such a way that there is Uttle liability
of sun scald. The first drooping system was originated by
William Kniffen, whose name is perpetuated in all modifications
of the system.

The following drooping systems are in common use: the
single-stem, four-cane Kniffen system; the two-stem, four-cane
Kniffen system; the Y-stem Kniffen system; the umbrella Kmffen




Pig. 10

system; and the one-wire, or low, Kniffen system. Other mod-
ifications of the drooping system have been devised, but for
one reason or another they are no longer in use in commercial
vineyards.

41. In the single-stem, four-cane Kniffen S3rstem

of pruning and training, which is illustrated in Fig. 10, a two-
wire trellis is used, the lower wire being from 3 to 3| feet above
the ground and the top wire about 2| feet above the lower wire.
If the vines are strong, training by this system can be begun



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§14



GRAPE CULTURE



33



the third year after setting, but if they are weak, it should be
deferred until the fourth year after setting. A single trunk,
or stem, is carried to the top wire and is tied to this and also
to the bottom wire; the trunk is kept in this position per-
manently. Two canes at the level of or just below each wire
are selected for leaving, and these are tied to the right and the
left along each wire. The two upper canes are left longer and
with more buds than the two lower. In the case of strong-
growing varieties like the Worden, each of the upper canes may
bear ten buds and each of the lower ones five, making thirty




Pic. 11

buds to the vine. Some growers prefer to have twelve buds
on each of the upper canes and only four on each of the lower.
These canes produce the fruiting shoots of the current year;
these shoots will mattire and form the canes from which the
four strongest will be selected for the succeeding year's growth.
At the winter pruning the four old canes of the previous year
should be cut away and with them all new growth except four
canes. It is not necessary that the canes left should be those
nearest to the tnmks, for it may be that these are the weakest;
but, other things being equal, these canes are preferable because
their selection keeps the spurs short. Each spring the four



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34 GRAPE CULTURE § 14

canes left after pruning should be tied to the right and the left
of the trunk along each wire. The spurs will lengthen rapidly,
consequently it will be necessary to remove them entirely
every 5 or 6 years. This can be done if well-placed shoots
that arise from time to time from the trunk are selected to be
. retained.

42. The two-stem, four-cane Knlffen system, which
is illustrated in Fig. 11, is very similar to the system just
described, the difference being that two permanent stems, or
trunks, are used instead of one. One stem is carried to the
top wire and two canes are taken off, one to the right and one to
the left, the canes being tied ; the trunk is tied to both wires and
kept in this position permanently. The other stem is carried to
the lower wire and tied, two canes being taken off and tied as




Fig. 12

in the case of the first stem. Some vineyardists prefer to tie
the two stems together in order to make them stiffer. In the
two-stem method of training, the canes taken off from each
stem may be the same length and have the same number of
buds, each stem being considered a distinct vine. Subsequent
pruning is the same as in the single-stem system.

43. The Y-stem Kniffen system differs from the two-
stem system in that instead of two stems being brought up from
near the groimd, one stem is taken from the other at a height a
little below the lower wire, and carried to the top wire where it is



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§ 14 GRAPE CULTURE 35

tied. This makes a Y-shaped joint in the vine, whence the
name of the method. The ntimber of canes laid down and the
subsequent treatment are the same as in the other systems
so far described.

44, In the umbrella Kniffen system, which is illus-
trated in Fig. 12, but two canes are used. The stem is carried
to the top wire, where it is tied. Two canes with from eight
to twenty buds each are taken from the spurs on the trunk
at the height of the top wire, and are tied to the right and the
left along this wire and then bent down to the lower wire and
secured. The canes are renewed yearly from spiu^.




Pig. 13

45. The one-wire Kniffen system, sometimes called the
low Kniffen system, which is illustrated in Fig. 13, is a modi-
fication of the umbrella Kniffen system. The trellis has but
one wire, which is placed 3 or 4 feet above the ground. The
single stem extends up to the wire, at which point two canes
with from 10 to 12 buds each are taken off and laid down to the
right and the left of the stem. The cane renewal each year, as
in the other systems so far discussed, is from spurs. The
quality of the fruit produced and the cheapness of the trellis
commend this system of training.

46. Upright Systems. — In the upright systems of pru-
ning and training, two or more canes or arms are carried



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§ 14 GRAPE CULTURE 37

horizontally along the wires or obliquely across them and the
shoots, as they develop, are tied to wires above. The follow-
ing upright systems are in common use: the high-renewal sys-
tem, the Keuka system, the horizontal-arm spur-renewal system,
the Chautauqua spur-renewal system, and the fan system.

47. The high-renewal system, which has much to
commend it, is illustrated in Fig. 14. An unpruned vine is
shown in (a), and the same vine is shown pruned in (6). The
trellis is usually made with three wires, the lower wire being
placed from 18 to 30 inches above the groimd, the second wire
18 inches above the first, and the third wire 20 inches above
the second. The main trunk, or stem, of the vine is carried
up to or just below the first wire, and two canes, each bearing
from six to ten buds, are taken off, preferably a little below the
level of the wire. One cane is tied to the right and the other
to the left. The bearing shoots that grow from the buds on
these canes are tied to the second wire when they have reached
a sufficient length, and to the third wire as soon as growth will
permit. When they reach above the upper wire, they may be
cut off or pinched back. The next year the vine should again
be cut back to two canes, cutting being as close to the head
as possible. Near the base of each cane, but on older wood
at the head of the stem, short spurs carrying two or three buds
are maintained, from which shoots develop and which in turn
are used to furnish the fruiting shoots of the following year.
Thus, the spurs are the means of renewing the fruiting wood.
From these statements it will be seen that the quantity of old
wood retained is reduced to a minimum, but that the work of
tying is much greater than in any of the drooping systems.

48. The Keuka system, which is practiced in the Keuka
Lake district of New York, is a modification of the high-renewal
system. The method of pruning and training vines by this
system is illustrated in Fig. 15; in (a) is shown a pruned but
unstripped vine, and in (6) the same vine is shown stripped. The
first year after being set the vines are allowed to grow at random
on the ground. At the beginning of the second year they are
pruned back to two buds. If the vines are strong growers



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38



GRAPE CULTURE



§14



they are tied this season to the lower wire of the trellis, which
is from 18 to 20 inches above the ground. At the b^;inning
of the third year the vines are cut back to a stem, or trunk,
from 10 to 20 inches high and are then tied to the lower wire.
The fourth year the vines consist of a short trunk and two or




three canes, each of from five to eight buds; these canes are
laid along the lower wire and tied. The shoots from these are
carried perpendicularly to the second wire, which is about
20 inches above the first wire, as fast as the growth will per-
mit; they are then carried to the third wire, which is about
20 inches above the second. The following year all the wood



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40 GRAPE CULTURE §14

is cut away except two or three canes that have grown from
the buds nearest the head of the trunk. These canes cany
from five to eight buds. K two canes are left they are tied
to the right and the left along the lower wire; if three are left,
the third is carried to the second wire and then tied, as shown
in the illustration. As there is a tendency for long spurs to
result from the repeated renewals secured in this maimer, buds
from the head of the stem are allowed to develop and fruiting
wood is secured from them. Thus, the fruiting wood arises
from near the head of the trunk, and as this is usually short,
almost the entire vine is renewed annually. When the trunk
approaches the end of its usefulness, a shoot is allowed to
grow from the ground and this eventually becomes the trunk,
the old one being cut away. The advantages of this method
of training are the low head, the reduction of the old wood to
a nMnimtun, and the ease of getting a complete renewal.

49. The horizontal-arm spur-renewal system is illus-
trated in Fig. 16. In (a) is shown a vine trained by this systan
before it was pruned, and in (6) is shown the same vine after it
was pruned. The trellis used in this system of pruning is prac-
tically the same as that used in the high-renewal system. The
trunk is taken up to a point at or just below the lower vine.
Two canes are taken from the head of the trunk and laid along
the lower wire, one to the right and the other to the left. The
number of buds to leave on each cane will depend on the vigor
of the vine and the distance between adjoining vines. These
canes are to become permanent arms and do service for several
years. The shoots that develop from buds on these canes
the current year are cut back in the fall or winter to two buds.
Two shoots are allowed to grow from each of the spurs thus
formed and are tied to the upper wires. In the fall the cane
developed from the upper bud of each spur is cut entirely away
and the other cane is cut to two buds as before. The spitfs
lengthen rapidly and become crooked, consequently it is advis-
able to cut them away entirely every few years and grow others
from shoots that arise from the arms. The spiu^ may be
distributed from 5 to 21 inches apart on the arms. ;_



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§ 14 GRAPE CULTURE 41

60. The Chautauqua spur-renewal system, which is
used by the grape growers of the Chautauqua district of New
York, is a modification of the horizontal-arm sptir-renewal
sjrstem. Permanent amfis are maintained to support the canes,
which are tied yearly to a two- or a three-wire trellis; the canes
may be tied obliquely or perpendicularly. If a two-wire trel-
lis is used, the wires are usually placed 34 inches apart; if a
three-wire trellis is used, they are placed about 20 inches apart.
The canes for tying up each year develop directly from the
old wood of the arms, or from spiu^ on the arms, or from the
base buds of the previous season's canes. The old arms should
be renewed at frequent intervals, as in time they -become
crooked and gnarled, and the extremities reach to a consider-
able distance from the head of the vine. The Concord grape
is well adapted for training by this system.

61. The fan system of training, although still used in a
few localities, is not nearly so popular as it was some years ago.
In this system, the renewals are made yearly from spurs near
the grotmd, very little old wood being retained. The shoots
are tied to the wires in the direction that they naturally assume ;
they may be tied vertically, horizontally, or obliquely across
the wires. In regions where grapes are grown for home use
and the climate necessitates winter protection, the fan system
may be used to advantage. One serious objection to the sys-
tem, however, is the tendency of the spurs to become long and
crooked.

62. Horizontal Training System. — Horizontal train-
ing is little used at the present time, as the cost of the trellis
and the labor required for tying the vines render it prohib-
itive. An ordinary two-wire trellis is used, but a strong stake
reaching to the top wire is driven at the side of each vine and
four perpendicular slats, which do not touch the ground, are
fastened to the trellis, two on each side of the vine and from
12 to 15 inches apart. Woven-wire fencing of narrow width
is sometimes used in place of slats. The vine is annually
renewed back to the trunk, which is from 1 to 2 feet high,
and a single cane and spur are left at each pruning, the cane



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42 GRAPE CULTURE § 14

being tied to the stake at the top. About six bearing shoots
on each side of this cane are left to grow; these shoots are tied
horizontally to the slats. One advantage of this system is
that the vines of varieties that are likely to overbear, or vines
that are weakened and need careful nursing, may be easily
controlled.

63. Pruning Systems for Vlnlfera Grapes. — ^Vinifera
grapes are commonly tied to stakes, although there are some
varieties that do better when trellised. Tieing to stakes, in
the case of varieties that will allow of it, has two great advan-
tages over trellising: First, staking is less expensive than trel-
lising; and, second, staking allows cultivating to be done in
both directions. Two general systems of pruning Vinifera
grapes are in vogue on the Pacific slope. These are known as
the short-pruning system and the long-pruning system. In the
short-pruning system the vines are tied to stakes; in the long-
pruning system they are sometimes tied to stakes and some-
times to trellises, depending largely on the variety. It should
be understood, however, that a great many modifications of
these general S3rstems are found in different localities.

54. The short-pruning system, which is known also
as the spur system and the stool system, is in general use on
the Pacific slope for stocky varieties. It is the simplest and
cheapest method of pruning and tieing vines. The vines
are usually staked, as has already been explained, at the end
of the first season's growth. The pruning at this time con-
sists of removing all but the strongest cane and cutting this
back to 12 inches in length, all lateral branches being cut away.
In Fig. 17 (a) is shown the appearance of a 1-year-old vine after
being pruned and tied.

The following season shoots are permitted to grow from only
the two uppermost buds. The two resulting canes are cut
back in winter to spurs of two buds each. The appearance of
a vine at this stage is shown in Fig. 17 (6). The following
year the two spurs are allowed to produce growth and the
resulting canes are again cut back to spurs and all of them
allowed to remain if the vine is ^rong. The appearance of a



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§ 14 GRAPE CULTURE 43

vine at this stage is shown in Fig. 17 (c). Thus a vine,
tmder ordinary conditions, consists, at the beginning of the
fourth year after planting, of a trunk from which spring four
or five arms, on each of which a cane has been cut back to
a sptir of from one to fotu* buds. When the vine is pruned the
following winter, all or nearly all of the canes that have grown
from the spurs are entirely removed. The spurs of the last
season are cut off just outside the inner canes, which are cut
back to spurs. The pruning each winter after this is to pro-
mote a regular system of sptir renewal. As the vines become
older and stronger and can stand more cropping, more spurs
are left to increase the fruiting capacity of the plant.



(d} (h)

Pig. 17

In the course of time the arms of the respective spurs are
renewed, and entirely new arms and spurs are grown. In the
case of some varieties in which the lower buds are not suf-
ficiently productive, the length of the spurs should be increased
and each sptir allowed to have four or even five buds.

Sometimes two or more trunks are allowed to come from the
same root; this is very imdesirable, as it increases the cost of
pruning and has no compensating advantage. When from
5 to 8 years old, a vine does not need the support of a stake,
consequently this may be removed.

66. The long-pruning system is used for strong-grow-
ing varieties such as Thompson's Seedless and the Sultana.



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44 GRAPE CULTURE § 14

Thompson's Seedless variety does best when trellised as shown
in Fig. 18. This is a modification of what is known as the
Guyot system of pruning, and is not only theoretically cor-
rect, but is easy to explain to pruners. The horizontal posi-
tion of the canes has a tendency to promote the starting of
numerous shoots and the consequent production of a large
number of fruit clusters. At the same time the buds on the
wood spurs are forced to start, and not being shaded they tend
to grow vigorously. It is best to tie the shoots from the wood
spurs in a vertical position to the stake, and they should not



-^



^!^



Pig. 18

be topped. These shoots are retained for fruit canes at the
winter pruning, and new wood spurs are then left for the next
year. This trellising system is now being used extensively
in the best vineyards of California where Thompson's Seedless
variety is grown.

A great many methods are in vogue for tieing long-pruned
vines to stakes. Perhaps the commonest method is to retain
from two to six fruit canes each year and an equal ntunber of
renewal spurs of two buds each, the canes being tied to a stake,
as shown in Fig. 19. The fruit is borne on shoots that arise
from these canes. A vine should not be drawn up close to the



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§ 14 GRAPE CULTURE 45

stake in the middle, but should be allowed to bulge out, as this
will cause the buds to push out better and render them more
fruitful. The stakes are retained permanently. Owing to
the fact that various modifications of this method are practiced



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