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The Complete Guide to Landscape Design, Renovation,
and Maintenance
by Cass Turnbull
FRUIT TREES
Ask five knowledgeable gardeners how to prune fruit trees and you
may well get five very different answers. This is because fruit
trees have grown for centuries as food sources rather than ornamental
trees. Therefore, everybody and his brother have developed a system
to maximize fruit production and to make it simple to pick all the
fruit, fast, and to make it easy to spray and to do more intensive
pruning to produce more and more fruit.
If You Only Want Fruit Production
If you want to maximize your fruit production, most County Extension
Services have inexpensive bulletins. They will explain early training
of young trees, pruning for production, and what to do with that
ugly old apple tree to bring it back into good shape. You will learn
the single leader method, the open center method, and the modified
central leader method. You will learn about Type IV tip bearers
with "blind wood." You will learn how to spread open young
limbs (some people use clothes pins) or to shore up old limbs with
2 x 4's to keep them from breaking. All the information in these
bulletins will help you produce lots of fruit, but if it seems like
too much work and you don't want to learn that much, try the Turnbull
method of pruning fruit trees. It is less work and you don't have
to concentrate as hard. It makes your tree look good and will produce
enough fruit to feed all your friends and family before it all rots.
But first, let's go over what not to do. The two most common errors
in pruning fruit trees are: (1) topping and (2) creating umbrella
trees with ugly sucker-laden crowns.
Pruning Errors
Topping is unequivocally bad for any tree, including fruit trees.
The suckers that shoot back up from a topped fruit tree will not
only be ugly, they are too busy trying to get enough leaves back
in order to feed the tree to make much fruit.
However, many orchardists will radically reduce the height of apple
and pear trees using the dropcrotch method of lowering trees. Dropcrotching
means you selectively head back to a side branch of a decent size,
say one-half the diameter. This is hard on the health of old trees
and opens them up to rot. Younger (fifteen years or less) trees
withstand this height reduction better. Dropcrotching reduces the
amount of sucker regrowth, as compared to topping, but does not
eliminate it. Do not use it as a way to keep your ornamental tree
small. More on that later.
Don't prune too much (no more than one-fourth total leaf surface)
in any one year. And, don't try to fix it all in one year. If you
have a tree that needs a lot of work, do it over several years.
The second error is the creation of umbrella trees. This happens
when the pruner cuts to an outside branch year after year--something
you might be tempted to do if you already know something about pruning.
This is called "bench-cutting."
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Two common errors in fruit tree pruning.
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Apical Dominance
We now need to understand apical dominance. This is the only hard,
technical part. Attention! Here is some basic tree and plant biology
which, when you get it, will make everything else clear to you,
and you can also impress your friends with some fancy words.
First, we will talk about the last bud on the end of a branch (the
terminal bud). It releases a chemical that, moving via gravity,
keeps the buds on down the line rather subdued. Think of it as the
boss-bud. When you cut off the end boss-bud, or even pull it over,
the chemical flow is disturbed and the other buds begin to grow.
Umbrella trees have terminal (boss buds) that are too low. Gravity
prevents the chemical from reaching buds down the line, so a crown
of suckers develops at the top.
To help keep your old apple tree from excessive crown suckering,
thin back low branches (they look like hooks) to a branch facing
more up and out.
Pick out a major scaffold branch and follow it with your eyes. Does
it dip down quite far, crossing other, lower scaffold branches and
cluttering things up? Then you may selectively head back (prune)
to one of its side branches that faces more upward and outward (forty
to sixty degrees is ideal). The scaffold branch now ends in a boss
bud with greater apical dominance (less gravity pull). This will
reduce the number of returning crown suckers farther back as well
as improve the looks of your tree. If you head back all the branches
(commonly done in old orchards) you involve yourself in a lot of
additional sucker work and the tree ages rapidly.
Keep in mind apical dominance if you attempt to reduce the height
of your apple or pear tree. It is a good idea to cut back a tall
vertical branch to a shorter branch which also faces upward. Basically
you are not trying to eliminate all vertical branches. You are simply
replacing them with shorter, younger, and fewer vertical branches.
This retains some apical dominance and allows the tree to grow a
little every year. It's like a volley ball game--you rotate out
a few of the tallest old suckers every year.
You may have a forest of suckers that are the result of previous
bad pruning. If you remove all of the suckers, they all come back.
Leave some to apically dominate the rest; shorten some to create
a second story up, and thin out the rest.
Note that the natural state of many old fruit trees is an umbrella,
which is all right if the umbrella is low down on the tree where
you can get the fruit, and if you don't care how it looks. But,
often the umbrella occurs high up on the tree, shading out the fruit
below, and spoiling the overall good looks of the tree.
Click here to see Apical Dominance.
 Pruning
Fruit Trees
So, how do you prune a fruit tree? The easiest way is just to prune
it like other trees: for health and good looks. First, and always,
take out the dead wood. Be thorough. Then take out some of the worst
crossing or rubbing branches, the worst branches going the wrong
way. These are the ones that start on one side of the tree, head
the wrong way through the center, and come out on the other side.
Also, thin back some of the branches, especially toward the top
(even a few big branches) to increase light penetration and to lower
your tree. This helps ripen the fruit lower down. It increases air
circulation, too, which is important in order to discourage the
numerous bacterial and fungal diseases that spoil the fruit. Look
for narrow, weak big-branch crotches. Heavy, fruit-laden branches
need to be strong. Narrow crotches are the ones that break.
Now, you could stop here and you would have a pretty good looking
apple or pear tree without too much trouble. It will have fruit.
But, if you want to do more, read on.
Pruning for Fruit Trees
Certain kinds of branches make more fruit buds or spurs than others.
These are the ones that are situated in a not-too-horizontal position.
You can pull or push new branches into such a position, or you can
just start cutting out the ones that aren't in the right place and
leave the ones that are. Nature makes fruit by sending up a young,
straight-up soft branch. It flowers on the tip and the flower turns
into a fruit. The weight of the fruit pulls this supple branch over.
As a branch gets older, it stiffens in a more horizontal position.
As the branch tips over, the apical dominance of the terminal bud
weakens and buds farther down the branch are released to form nice
little side branches (laterals) and on them, teeny, tiny one-quarter-inch
branches called spurs. These tiny spurs have fat flower buds (fruiting
buds) on them rather than skinny leaf buds. We want the laterals
and spurs.
 In
the winter, it is the fat-budded spurs that you see on trees that
make you think it might be a fruit tree you're looking at. You can
encourage some, but not all, of your side branches (laterals) to
make spurs by heading (also called tipping back) to two or three
buds. This works on pears and apples, but it doesn't work on cherries.
Now, if your main branch gets pulled too far over--past ninety degrees,
you start to release too many buds from apical dominance, and those
miserable suckers start charging back up.
 In
some senses pruning fruit trees breaks all the rules for ornamental
tree pruning. You try to keep your tree small, something which should
never be done to other trees. Pruners often reduce fruit trees dramatically--which
would be extremely bad pruning on a maple or oak. We also head a
lot. We head side branches (laterals) to force them to make spurs.
We shorten major scaffold branches with heading, especially young
ones, so that they won't swing in the wind and lose fruit. Heading
causes these branches to get fatter or stouter. We need stout branches
to hold up heavy fruit. On apples and pears, especially, we do a
lot of heading. Peaches, nectarines and Japanese prunes really like
it when we whack and whale. However, don't do it to your cherries
or European plums.
Let's recap what we've gone over thus far. Prune your fruit tree
like any other tree:
1) First, and always, take out all of the dead wood.
2) Take out the worst crossing, rubbing branches.
3) Take out the worst wrongway branches.
4) Take out some, not all, of the suckers.
5) Remove weak crotches if they are or will become part of the main
framework (scaffold) branches.
6) Thin (not strip) all these branches rather than head, and do
more thinning on the top to encourage light penetration and air
circulation.
When dealing with suckers on your fruit tree, remember to: 1) cut
some out altogether; 2) leave some alone (don't cut off the tips),
since they will flower and fruit and be pulled over and produce
more spurs later; 3) head back some suckers to thicken them up into
second story branches. Try to head back to another upright, side
branch and not to a horizontal branch which would sucker back madly.
If you want to encourage more fruiting on your apples and pears,
you can prune for more horizontal branches. You can head back laterals
to force more spurs to form. See, you're an expert already!
More About Fruit Trees
Here is more information about fruit trees.
(1) Pruning of young trees (under six years) is done to develop
strong, low framework branches and not much else. In fact, it may
take a while longer for your tree to fruit. Go easy in the early
years. There are some newer varieties that fruit earlier.
(2) Old trees can be invigorated by heavy pruning to produce new
wood and spur systems, although you may experience a temporary drop
in production when you cut off older and lower limbs or "hooks."
(3) Summer pruning of fruit trees is all right if the tree is
vigorous and healthy and well watered. Summer pruning can be useful
for spotting dead wood (no leaves). It can be useful in reducing
the spread of fungus-bacterial diseases which like damp weather,
and it will help reduce suckering. It generally slows the growth
rate and will help restrict the size of your tree. It is harder
on the plant, however, so go easy, and never prune during a drought.
(4) Proper horizontally placed branches are only one factor in
fruit production. Many fruit trees need a cross-pollinator tree
in the neighborhood. The Cooperative Extension Service in your area
has lists of what type of tree pollinates what for you and which
fruit trees do well. Cross pollinators are something to consider
when you are planning your orchard.
(5) New dwarf varieties called "spur type" apples don't
need to be pruned to make them set up spurs. They do it themselves.
In fact, be careful that you don't prune them off.
(6) Bee activity is needed for pollination. If it has been a very
wet spring, you may not get enough bee activity. Bees, like some
Park Department workers I know, won't work in the rain. On the other
hand, if you don't see any bees and it has been sunny, it may be
that someone in your neighborhood has inadvertently killed them
with pesticides. Misapplication of some commonly used pesticides
can wipe out entire hives. If your neighbor doesn't read the label
and applies something like Sevin on plants in bloom during the middle
of the day, a bee might bumble into a flower and then carry the
poison back to the hive and kill the entire hive. This is a tragedy
for the orchardist as well as the bees.
(7) Fruit trees need sun in order to flower and fruit. If your
tree never sets fruit, stand next to it and look up. If you see
big trees or condominiums, this may be your problem. You're in too
much shade. Try removing your fruit tree and planting a vine maple,
Japanese maple or other understory tree. They look nice and do well
in these conditions.
(8) Fruit trees, especially Gravenstein apples, sometimes get
into an every-other-year routine, which can be modified by pruning.
If you wish, you can ignore it. Your tree may be too young. You'll
have to wait, be patient! Your tree may be too old. You'll have
to prune it or remove it and replace it with something you like
better.
(9) You can improve the size and quality of your fruit by thinning
branches so more light gets to the interior of the tree. Also, you
can thin spurs and baby fruit, so that more energy gets put into
the remaining branches or buds for bigger, tastier fruit. Don't
go overboard though, you might get "bitter pit," "cork,"
or other fruit tree maladies. Now that you know the basics, and
how to be patient and moderate, you can develop your own best method
of pruning.
(10) There is a difference in the severity of pruning of European
and Japanese plums. Japanese plums should be pruned heavily, like
peaches; the strong upper wood should be cut back to weaker branches.
Whack! Whack! Whack! Japanese plums and European plums will not
cross pollinate each other.
(11) These days you don't have to suffer with big fruit trees,
nurseries now have new dwarfing rootstocks. So, if you want fruit
and less work, chop down that old tree and plant a new dwarf one.
Dwarfing rootstocks come in small, smaller, and very small. Check
it out with your Extension Service. A really smart sized fruit tree
is about four feet tall. Unless, of course, you love that old tree--then
keep it.
(12) Do not try to make your cherry tree small again by topping
it. It won't work. They have yet to develop a really good dwarfing
rootstock for cherry trees. That's why that big bucket truck with
the seventy foot extension is called a "cherry picker."
(13) People often want to lower cherry trees because they cannot
stand the waste of the fruit on the top they cannot reach. Removing
the top would not actually increase cherry production down low.
Other people welcome the day when the tree gets tall enough that
the birds leave the lower cherries alone.
If after reading this chapter it all seems very confusing and self-contradictory,
well, it is. Even people who specialize in fruit tree pruning are
often unsure and easily swayed to other methods and ways. Take heart,
teachers send students out to practice on apples and pears because
these trees are so forgiving. In eastern Washington, machines mow
them to force fruit production. Stay away from topping--especially
your cherry tree, and you'll do okay.
SUMMARY
Fruit trees, like roses, are for people who like to prune and spray
a lot. Try buying very, very dwarf, disease resistant trees to reduce
these maintenance chores. You can, if you like, prune fruit trees
like ornamentals, for health and good looks, and leave it at that.
Horizontal branches bear more fruit than vertical branches.All fruit
trees are not created equal.
Group A:
Peach Head a lot
Apricot Prune hardest
Nectarine
Japanese Plum
Group B:
Apples Keep young trees short
Pears Head laterals to encourage fruit spurs Prune medium
Group C:
Cherries Hard to keep trees short with pruning.
European No topping
Plums No heading laterals
Least pruning
Train early by bending branches.
Forward to How to Prune a Tree Limb
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