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Pruning Other Fruit Trees
The general purpose of pruning fruit trees is to regulate growth,
increase yields, improve fruit size and quality, and reduce
production costs. Pruning is necessary to shape trees for
convenience of culture and repair of damage. |
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Most pruning is done during the dormant season,
preferably just before active growth begins in the spring but can
continue through flowering, however bees may become problematic.
At this time pruning wounds heal quickly, flower buds can be
easily recognized, and injury from low winter temperature is
avoided. Summer pruning may be done to help train trees to the
desired form and maintain small tree size. It should be
remembered, however, that all pruning has a dwarfing effect. For
maximum yield of high quality fruit, prune only as needed to
establish a tree with a strong framework capable of supporting
heavy crops annually without damage and to maintain a tree
sufficiently open to allow penetration of sunlight, air, and spray
material for good fruit development and pest control. |
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Pear trees are trained as a central border tree along
the same general lines as those recommended for apples. Pears have
a very upright growth habit and must be spread early in training.
Tipping or heading back the long shoots slightly will encourage
development of side branches. Heading back after the framework has
been developed is undesirable because of the tendency of the tree
to throw out soft terminal shoots, which are highly susceptible to
fire blight. It is best to limit pruning to thinning-out cuts.
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Sweet cherry and apricot trees are trained to the
modified leader system that is similar to the one recommended for
the apple except for annual thinning back of the central leader to
a less vigorous, upright side shoot should be done. Special
attention should be given to the selection of scaffold limbs
because sweet cherry is subject to winter injury and splitting at
the point where the limbs join the main stem of the tree. It is
essential that the crotch angles be as wide as possible to ensure
a strong framework, because sweet cherries have an upright growth
habit. This must be done by spreading early in training sweet
cherry trees. Apricots are fairly easy to train and prune.
Thinning out of crowded branches and those blocking light into the
center of the tree should be removed. |
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A sour cherry tree, with no strong branches at the time
of planting, should be headed to about 24 inches above the ground.
Selection of laterals can be made at the beginning of the second
years growth. If it has some good laterals when planted,
remove those lower than 16 inches from the ground. Select about
three or four permanent lateral or scaffold limbs along the
leader, 4 to 6 inches apart and not directly over one another. Do
not head them back, since this tends to stunt terminal growth. |
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In the following years, select side branches from the
leader until there is a total of 5 or 6 scaffold limbs well
distributed above the lowest branch along 3 or 4 feet of the main
stem. The leader is then usually modified by cutting to an
outward-growing lateral. After fruiting begins, pruning consists
mainly of thinning out excessive and crowded growth each year to
allow sunlight to filter through the tree. |
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Peach and nectarine trees are usually trained to the
open-center system. Newly planted trees should be headed to about
30 inches in height, just above a lateral branch or bud. If the
tree is branched when it comes from the nursery, select 3 to 5
laterals, 4 being ideal, well-spaced up and around the trunk, for
the permanent scaffold limbs. The lowest limb should be about 15
inches and the highest about 30 inches from the ground. Cut these
back to two buds each, and remove all other laterals. A shoot
should not be allowed to grow into the center of the tree. |
If no desirable laterals are available, head the tree
to the desired height and cut out all side branches to one bud. A
number of shoots will develop during the season, from which you
can select scaffold limbs. Selection can be made during the summer
or delayed until just before growth begins the second season. |
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Once the scaffold system of the young peach tree is
established, prune as little as possible until the tree begins to
bear. Remove all strong, upright shoots growing in the center of
the tree, and lightly head back terminal growth on the scaffold
limbs to outward-growing laterals. This aids in the development of
an open-center tree. |
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As fruit is borne on wood of the previous years
growth, it is necessary that the peach be pruned annually to
stimulate new growth and maintain production near the main body of
the tree. Pruning of the mature peach tree consists mainly of
moderate thinning and heading back to outward-growing laterals to
keep the tree low and spreading. A height of 8 or 9 feet is
usually preferred. |
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The plum may also be pruned in a manner similar to the
apple. European and prune types generally develop into well-shaped
trees, even if little pruning is done. Thinning out excessive
growth constitutes the bulk of pruning after heading back to 30 to
36 inches at the time of planting. Varieties of the Japanese type
are usually a little more vigorous and may not be pruned to an
open-center. They may need some heading back as well as thinning
of excessive growth after they come into bearing. |
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Special Training System
The foregoing suggestions for pruning fruit trees are concerned
with training for maximum production of high quality fruit. In
addition, many home gardeners prune for decorative purposes. |
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Numerous training systems, based on the art of
espalier, which originated in France and Italy about 400 years
ago, have been devised. Some are quite elaborate, requiring
considerable time and patience as well as detailed knowledge of
the plants growth characteristics. The easiest espalier
system is the horizontal cordon. Apples, pears, and plums adapt
well to this system. The trees are usually supported by a wall,
fence, or wire trellis. Training to the four-tier cordon or
four-wire trellis is relatively easy. |
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An espalier system can serve to separate yard areas and
to provide an effective way of producing a large volume of high
quality fruit in a limited area. Trees trained in this fashion
should be grafted on dwarfing rootstock. Otherwise, they tend to
grow too large and are difficult to hold within bounds. |
First Winter
Second Winter
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A simple, four-wire trellis may be constructed by
setting 8-foot posts 2 feet in the ground, spacing them 12 feet
apart, and running wires through the posts at heights of 18, 36,
54, and 72 inches. Plant two unbranched whips of the desired
variety 6 feet apart between each two posts. |
Before growth begins in the spring, cut off the whip
just above the first bud, below the point where the whip crosses
the lowest wire. Usually three or more shoots will develop near
the point of the cut. Retain the uppermost shoot and develop it as
the central leader. The other two can be developed into main
scaffold branches to be trained along the lower wire, one on each
side of the central stem. Remove all other growth. The two shoots
selected for scaffold limbs should be loosely tied to the wire as
soon as they are 10 to 12 inches long. Twine, plastic ties, or
other suitable material may be used. Tie the shoots so that they
are nearly horizontal. This reduces vegetative vigor and induces
flower bud formation. If the end of the shoot is tied below the
horizontal, however, new growth at the end will stop, and vigorous
shoots will develop along the upper side. At the end of the first
season, the lateral branches on the lower wire should be
established and the central leader should have grown above the
second wire. |
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During the dormant pruning at the end of the first
winter, cut the central leader off at a bud just below the second
wire. Repeat the process of the previous spring by developing two
scaffold branches to tie to the second wire and allow the central
leader to grow above the third wire. |
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This process is repeated during the next two seasons,
at which time a total of eight scaffolds, four on each side of the
tree, should be firmly established. The leaders should be bent to
form one of the scaffolds, rather than being cut off at the top
wire. |
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By the end of the fourth season, the trees should be in
heavy production. All pruning is then done during the spring and
summer months. After new growth in the spring is about 2 inches
long, cut it off, and also removing about 1/4 of the previous
seasons growth. Terminals of the scaffold are left
untouched. |
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About the first of August, or as soon as new growth
reaches 10 to 12 inches in length, cut it back to two or three
buds. Repeat about a month later, if necessary. This encourages
fruit bud formation and prevents vigorous growth from getting out
of bounds. |