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Training & Pruning Fruit
Trees
AG-29
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Growers
often neglect the annual training and pruning of fruit trees. Without
training and pruning, however, fruit trees will not develop proper
shape and form. Properly trained and pruned trees will yield high
quality fruit much earlier in their lives and live significantly
longer.
A primary
objective of training and pruning is to develop a strong tree
framework that will support fruit production. Improperly trained
fruit trees generally have very upright branch angles, which result
in serious limb breakage under a heavy fruit load. This significantly
reduces the productivity of the tree and may greatly reduce tree
life. Another goal of annual training and pruning is to remove dead,
diseased, or broken limbs.
Proper tree training also opens up the tree canopy to maximize light
penetration. For most deciduous tree fruit, flower buds for the
current season's crop are formed the previous summer. Light
penetration is essential for flower bud development and optimal fruit
set, flavor, and quality. Although a mature tree may be growing in
full sun, a very dense canopy may not allow enough light to reach 12
to 18 inches inside the canopy. Opening the tree canopy also permits
adequate air movement through the tree, which promotes rapid drying
to minimize disease infection and allows thorough pesticide
penetration. Additionally, a wellshaped fruit tree is aesthetically
pleasing, whether in a landscaped yard, garden, or commercial
orchard.
Table of Contents
Pruning vs. Training
Historically, fruit tree form and structure have been maintained by
pruning. Tree training, however, is a much more efficient and
desirable way to develop form and structure.
Pruning is the removal of a portion of a tree to correct or maintain
tree structure. Training is a relatively new practice in which tree
growth is directed into a desired shape and form. Training young
fruit trees is essential for proper tree development. It is better to
direct tree growth with training than to correct it with pruning.
Pruning is most often done during the winter, commonly referred to as
dormant pruning. Training includes summer training and summer pruning
as well as dormant pruning. The goal of tree training is to direct
tree growth and minimize cutting.
Dormant Pruning vs. Summer Pruning
Trees respond very differently to dormant and summer pruning. Dormant
pruning is an invigorating process. During the fall, energy is stored
primarily in the trunk and root system to support the top portion of
the tree. If a large portion of the tree is removed during the
winter, while the tree is dormant, the tree's energy reserve is
unchanged. In the spring, the tree responds by producing many new
vigorous, upright shoots, called water sprouts, which shade the tree
and inhibit proper development. Heavy dormant pruning also promotes
excessive vegetative vigor, which uses much of the tree's energy,
leaving little for fruit growth and development.
Historically, much of the vigorous, upright vegetative growth has
been removed during the dormant season; heavy dormant pruning results
in a yearly cycle with excessive vegetative growth and little or no
fruit production.
Timing of dormant pruning is critical. Pruning should begin as late
in the winter as possible to avoid winter injury. Apple and pecan
trees should be pruned first, followed by cherry, peach, and plum
trees. A good rule to follow is to prune the latest blooming trees
first and the earliest blooming last. Another factor to consider is
tree age. Within a particular fruit type, the oldest trees should be
pruned first. Younger trees are more prone to winter injury from
early pruning.
Summer pruning eliminates an energy or foodproducing portion of the
tree and results in reduced tree growth. Pruning can begin as soon as
the buds start to grow, but it is generally started after vegetative
growth is several inches long. For most purposes, summer pruning
should be limited to removing the upright and vigorous current
season's growth; only thinning cuts should be used. To minimize the
potential for winter injury, summer pruning should not be done after
the end of July.
Types of Pruning Cuts
Thinning Cut - removes an entire shoot back to a side shoot.
Thinning cuts do not invigorate the tree in comparison to some of the
other pruning cuts.
Heading Cut - removes only the terminal portion of a shoot.
This type of cut promotes the growth of lower buds as well as several
terminal buds below the cut. When lateral branches are headed into
oneyearold wood, the area near the cut is invigorated. The headed
branch is much stronger and rigid, resulting in lateral secondary
branching. Older trees can be held in their allotted space by mold
and hold cuts, which are devigorating heading cuts made into
twoyearold wood. Young trees and branches where heading cuts are made
will be referred to as headed.
Bench Cut - removes vigorous, upright shoots back to side
branches that are relatively flat and outward growing. Bench cuts are
used to open up the center of the tree and spread the branches
outward. This is a major cut and should only be used when
necessary.
When making pruning cuts, it is important to use techniques that will
allow the cut surface to heal quickly. Rapid healing minimizes the
incidence of disease and insect infection. Pruning cuts should be
flush with the adjacent branch without leaving stubs. Also, when
large horizontal cuts are made, they should be slightly angled so
that water does not set on the cut surface, allowing the growth of
rot and disease organisms.
Many compounds are available as wound dressing or pruning paints. But
the best treatment is to make proper pruning cuts and allow the tree
to heal naturally. If preferred, tree paints and wound dressing may
be used for aesthetic reasons, but they will not promote healing.
Training Systems
One of the most frequently asked questions is, "To what shape should
I train my fruit tree?"
It is difficult to give one answer. You can choose from many
different training shapes and forms with multiple variations on each
form. This bulletin focuses primarily on the central leader and open
center training systems for mediumdensity orchards. A list of fruit
trees conventionally trained to each system is also included. A fruit
tree may be trained to any system. Depending on the form and function
of the desired shape, you may want to train a tree to a
nontraditional system.
Whatever system is chosen, keep in mind that the objectives of
training and pruning are to achieve maximum tree life and
productivity.
Central Leader Training - Apple,
Cherry, Pear, Pecan, Plum
A central leader tree is characterized by one main, upright trunk,
referred to as the leader. Branching generally begins on the leader
24 to 36 inches above the soil surface to allow movement under the
tree. The first year, 3 to 4 branches, collectively called a
scaffold whorl, are selected. The selected scaffolds should be
uniformly spaced around the trunk, not directly across from or above
one another. Above the first scaffold whorl, leave an area of
approximately 18 to 24 inches without any branches to allow light
into the center of the tree. This light slot is followed with another
whorl of scaffolds. Alternating scaffold whorls and light slots are
maintained up the leader to the desired maximum tree height. See
Figure 1.
The shape of a properly trained central leader tree is like that of a
Christmas tree. The lowest scaffold whorl branches will be the
longest and the higher scaffold whorl branches will be progressively
shorter to allow maximum light penetration into the entire tree.
Developing a Central Leader Trained Tree At Planting
Fruit trees are frequently purchased as whips, which are unbranched
trees ranging from 1/2 to 3/4 inch diameter. The tree should be
planted in early winter with the graft union 2 inches above the soil
surface. Just before the buds start to grow in the spring, the tree
should be headed, or cut off, at 30 to 34 inches above the soil
surface. The height at which the tree is headed depends upon where
you want the first whorl of branches. Once the tree is headed,
permanent branches will be selected from buds growing within 4 to 12
inches below the heading cut. See Figures 1 and 2.
Figure 1. Pruning a central leader tree
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At Planting
As the buds begin to swell, head the tree at 30 to 34 inches
above the soil surface.
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Dormant Pruning
Head the tree at 24 to 30 inches above the highest branch of
the first scaffold whorl.
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Top View
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First-Year Summer Pruning
Summer prune when new growth is 3 to 4 inches long. Leave
a as the new leader, and remove b and
c. Select four uniformly spaced laterals for the
first scaffold whorl, and remove the remaining lateral
branches.
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After pruning the third year
Three scaffold whorls have been developed with three to four
branches uniformly spaced around the tree in each whorl. A
light slot of 18 to 24 inches is left between each scaffold
whorl. Note the Christmas-tree shape that allows light
penetration to the lower branches and interior of the tree.
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Steps in Pruning:
- Leave only one trunk for the central leader.
- Remove branches with crotch angles less than 60
degrees.
- Remove all branches directly across from one another
on the leader.
- Space lateral branches uniformly around the leader to
prevent crowding as the limbs grow in diameter.
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Figure 2. Newly planted apple tree headed back
Summer Pruning
After the new vegetative growth has reached 3 to 4 inches in length,
summer pruning should begin. The first step is to select one upright
shoot near the top of the tree to be the leader. After selecting the
leader shoot, remove all other competing shoots for approximately 4
inches below it; rehead the tree above this leader. See Figures 3 and
4.
Figure 3.
Left: Heading an apple tree at planting
results in several competing
shoots
below the cut.
Right: For central leader tree, a
single leader needs to be selected by
removing
the undesired shoots.
Figure 4. Central leader plum trees must also have competing
shoots removed.
At this time, side shoots (laterals) should be spread out to form an
angle of 60 to 70 degrees between the leader and the side shoot. This
angle is referred to as the branch or crotch angle. Branches that do
not have a wide branch angle are overly vigorous and have a weak
point of attachment to the leader. These branches frequently break
under a heavy fruit load. Spreading the lateral branches will also
slow the growth of the branches to a manageable level and promote the
development of secondary or side shoots on the scaffolds. When growth
is only 3 to 4 inches, toothpicks or spring clothespins can be used
to spread branches. See Figure 5. After a proper branch angle is
attained, clothespins can be moved to the ends of longer limbs to
weigh down the branches as they start to grow upward.
Figure 5. Central leader apple trees. Toothpicks are used to
spread the lateral branches outward during the first growing
season.
During the first year, minimize further summer pruning. Limit it to
the removal of shoots growing upright or downward. Summer is the
optimal time to select the leader and scaffold branches and remove
undesirable growth. Branches lower than the desired height should
also be removed. A young orchard or tree should be summer trained and
pruned once a month through July to remove unwanted growth and to
properly orient young branches. Summer pruning will greatly reduce
the amount of dormant pruning needed.
Failure to summer prune the first year will result in an
improperly trained tree, and drastic dormant pruning will be required
to correct tree structure.
Succeeding Years
Managing the central leader is one of the most important aspects of
dormant pruning. The leader should be headed at approximately 24 to
30 inches above the highest whorl of scaffolds to promote continued
branching and scaffold whorl development. Dormant pruning should also
eliminate dead, diseased, and damaged wood. Unwanted growth, such as
upright growing shoots and laterals with sharp branch angles not
removed during summer pruning, should also be removed at this time.
Unbranched lateral branches should be headed back by approximately
1/4 of their length to encourage side branches and to stiffen lateral
branches.
Summer pruning in succeeding years should eliminate competing shoots
where dormant heading cuts were made (on the central leader and
laterals) as in the first year. Summer is also the optimal time to
remove unwanted side shoots and excessive growth. All laterals should
have a wide branch angle, and spreading of lateral branches is
essential for many varieties. Lateral branches will need to be spread
for about the first five years, using a larger spreader each
year.
Spreaders can be made with 1inchsquare wood pieces with a finishing
nail driven in the end and cut off at an angle. Spreaders are
frequently made in lengths of 6, 12, and 18 inches. See Figure 6.
Figure 6. Wooden limb spreaders can be made from wood and
finishing nails in various lengths.
Spreading branches in later years reduces vigor and promotes fruit
development on the lateral branches. The reduced growth rate and the
weight of the crop load will also help pull the branches down to a
proper angle. However, it is important that the young tree is not
allowed to crop too early where the weight of the fruit pulls the
branches below horizontal. Once the branches are below horizontal,
they are weak and nonproductive and need to be removed and replaced.
See Figure 7.
Figure 7. Well-trained apple trees. Note the branch angles and the
development of scaffold whorls.
Another objective of dormant pruning is to control the length of the
lateral branches. In order to maintain the Christmastree shape
(Figure 1), lateral branches need to be cut back. Once the tree has
reached its desired height and lateral spread, it will be necessary
to mold and hold the lateral branches and the central leader with
heading cuts. This can be done by cutting the laterals and leader
back into twoyearold wood to a sidegrowing shoot. It is a good rule
to cut back to a side shoot that is close to the same diameter as the
lateral or leader being cut.
Mature Trees
Mature trees that have been properly trained and summer pruned will
require minimal pruning. The first step would be to remove dead,
diseased, and damaged wood and then upright shoots and shoots below
horizontal. To prevent shading, it is important to maintain the
Christmastree shape by heading lateral branches with mold and hold
cuts. See Figure 8. For quality fruit production, it is also
essential that the light slots between the scaffold whorls be
maintained.
Figure 8. Mature, well-trained apple trees, left, and pecan
trees, right. Note that the distance between branches needs to be
increased for larger trees.
Mature fruit trees that have not been properly trained frequently do
not have a true central leader shape. For those trees, the objectives
of training and pruning as discussed earlier must be considered. In
many cases, too many lateral branches and upright limbs (some may be
6 or more inches in diameter) have been left and need to be removed
to allow proper light penetration. This pruning needs to be done
during the dormant season.
Neglected trees often have overgrown tops that act as an umbrella,
shading the rest of the tree. The tops of these trees need to be cut
back or removed. Remember, if the principles of pruning are followed,
there are no perfect cuts and no incorrect cuts. However, do not
remove more than 30 percent of the tree top to avoid shifting the
tree into an excessively vegetative state with little fruit
development.
Pecan Tree Consideration
Pecan trees should be trained to a central leader. The lateral
branches, however, should be spiraled up the leader. Approximately 12
to 15 inches should be left between branches for adequate light
penetration initially. As the tree matures it will be necessary to
remove branches to prevent crowding and allow light penetration. See
Figure 8, above.
Modifications of the Central Leader
Multileader Tree
A multileader tree is the goal of another training system and an
ideal option for pear varieties that are susceptible to fireblight.
With a multileader tree, if one leader is infected with fireblight,
it may be removed without loss of the major portion of the tree. See
Figure 9.
Figure 9. An apple tree trained to a multileader system. This
would be an ideal training system for pear trees in North Carolina
where fireblight is a threat.
The multileader tree uses the same concept as the central leader tree
except there are several leaders in the center of the tree. Each
leader is maintained the same as an individual central leader tree.
The only difference in training a multileader from the central leader
is that in the first and second year instead of removing the
competing leaders, several should be left and maintained. On the tree
in Figure 1, it would be necessary to leave shoots a, b, and c for a
multileader tree. However, it would be necessary to put spreaders
between the selected leaders to get the shape of the tree in Figure
9.
HigherDensity Central LeaderTraining Systems
In the commercial apple industry, there is much interest in
higherdensity orchards with 1,000 or more trees per acre. The first
requirement for higherdensity systems is smaller trees, which is
accomplished with sizecontrolling rootstocks. Two of the betterknown
higherdensity training systems are the slender spindle and vertical
axe. Both are modified central leader trees with branches continually
along the central leader to the top of the tree. Light penetration is
not a problem as the maximum height of the tree is limited to
approximately 6 to 12 feet, with a canopy spread of 3 to 4 feet
outward from the leader.
There are many other types of higherdensity training systems, some
with elaborate trellis systems. The slender spindletype tree is the
most popular highdensity training system. Highdensity training
systems, however, will not be discussed in this bulletin because of
the differences in management practices.
OpenCenter or Vase Training - Peach,
Nectarine, Plum
With the opencenter system, the leader is removed, leaving an open
center. Instead of having a central leader, the opencenter tree has 3
to 5 major limbs, called scaffolds, coming out from the trunk. This
training system allows for adequate light penetration into the tree,
which minimizes the shading problem prevalent in highervigor trees
such as peach.
At Planting
At planting, peach trees should be set so that the graft union will
be 2 inches above the soil surface. As the buds begin to swell, the
unbranched trees (whips) are generally headed approximately 30 to 34
inches above the soil surface. As discussed with the central leader
system, new branches will come from the buds that are 6 to 9 inches
below the heading cut.
Trees that are branched at planting are handled differently than the
whips. The work that needs to be done under the tree determines the
appropriate height for branching, which is usually 24 to 32 inches.
Remove branches that are too low. If there are 3 to 4 uniformly
spaced branches around the tree that can be selected as scaffolds,
the tree is headed just above the highest selected scaffold. Any
remaining branches not selected as scaffolds should be removed.
However, if there are less than 3 scaffolds the tree should be cut
back to a whip and the side branches removed. See Figures 10a and
10b.
Summer Pruning
After the new vegetative growth is approximately 3 to 4 inches long,
it is time to select the shoots that will become the major scaffolds.
The lowest scaffold should be 24 to 32 inches above the soil surface
to avoid interfering with cultural work under the tree, such as
harvesting and weed control. It is best to select 3 to 4 scaffolds
that are uniformly spaced around the tree, with wide branch angles,
and not directly across from another scaffold. See Figure 10a.
Figure 10a. Training and pruning young peach trees.
Left: Well-branched peach tree to be
trained to an open-center system
Right: 3 to 5 well-spaced scaffolds re
selected and the tree is headed
above the highest scaffold.
During the summer, these shoots should be spread out to a 45 to 60
degree angle and held in place with a toothpick or clothespin. All
other upright growth should be removed. It is best to come back
through every month during the summer to remove upright growth that
is shading the primary scaffolds and to make sure that the scaffolds
have been spread to a proper angle. Many times the crotch angle is
proper initially, but as the scaffolds grow, they turn upright. A
spring clothespin placed on or near the end of a shoot will pull the
scaffold down to a proper angle. Extreme care must be taken when
using the clothespins as weights. Periodic checking is essential to
assure that the scaffolds are not too flat.
Figure 10b. Training and pruning young peach trees.
Left: Tree after heading, branches
lower than 24 inches are also removed.
Right: Top view of uniformly spaced
scaffolds.
Succeeding Years
After the first year of growth, the primary scaffolds should be
selected and properly trained outward. Scaffolds should be headed
during the dormant season of the first three years to promote
continued lateral branching on the scaffolds and to stiffen and
strengthen the scaffold. Scaffolds should be headed to outwardgrowing
shoots similar in angle to those being removed. Bench cuts should be
avoided. See Figure 11a.
Figure 11a. Dormant pruning a mature open-center peach
tree.
Left: Tree before pruning.
Right: Heading a scaffold to an outward
growing shoot.
If summer pruning is being practiced, undesirable shoot growth can be
removed as soon as growth is 4 to 6 inches long. Summer pruning can
also be used to direct scaffold growth outward to the desired growing
points instead of waiting until the dormant season.
For bearing trees, the goal of dormant pruning is to remove vigorous
upright growth on the scaffolds and trunk that was not removed during
the summer. See Figure 11b.
Figure 11b. Dormant pruning a mature open-center peach
tree.
Left: Removal of vigorous upright
shoots in the center of the tree.
Right: Tree after pruning.
The upright growth left in the tree during the growing season may
shade out lateral growth near the trunk. This shading causes lateral
fruiting wood only on the ends of the scaffolds, which results in
broken scaffolds under a heavy fruit load. It is best to keep the
fruiting wood on the scaffolds as close to the tree trunk as possible
to reduce tree breakage and to produce the highestquality fruit.
Also, during the dormant season, damaged, dead, and diseased wood,
such as cankers, should be removed from the tree. Shoots with
shriveled and dried fruit from the previous season, called mummies,
should also be removed from the orchard to reduce disease pressure
for the coming season.
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Commercial Horticulture ] [ Educational
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Prepared by
Michael L. Parker, Extension Horticulture Specialist
AG-29
