An
Alternative to Tree Staking
Many arborists now agree that the disadvantages of staking and guying
trees far outweigh the advantages. The current trend in thinking is
that staking impedes normal tree growth and is detrimental to tree health.
In his
article, "Should Newly Planted Trees Be Staked and Tied?" William
R. Chaney answers the question simply. "In most cases, no. It is
crucial that trees experience movement caused by the wind to develop
properly."
Chaney,
who is a professor at Purdue University's Department of Forestry and
Natural resources, notes that supporting trees with stakes and guys
can go beyond unnecessary to detrimental.
Blowing
in the Wind
Jay Banks, arborist with the town of Leesburg, VA, explains. "Research
has shown that by staking trees you reduce the development of trunk
taper, which means the tree's ability to grow in response to the prevailing
winds. Staking can also lead to a tree snapping in half if the guy wires
are placed too low on the trunk."
Marianne
C. Ophardt, an area extension agent with the Washington State University
Cooperative Extension, says that staked treesespecially those
improperly staked, which happens all too oftentend to develop
smaller root systems and thinner trunks. "The movement of the tree
trunk in the wind stimulates plant hormones that, in turn, stimulate
root and trunk growth. When a tree is staked in a manner that prevents
any movement of the trunk, the tree doesn't establish and grow as strong.
This is why young trees that are staked are often unable to stand upright
when the staking is removed."
Staking
Is Easy At First, But Requires Follow-up
Paul Wray of the Iowa State university Forestry Extension agrees with
Ophardt that small trees less than six-feet tall or less than one-inch
in caliper or diameter should not need staking to support them. Ideally,
though, the tree should be watched after planting to make sure.
"As
tree planting stock gets larger, their root system, ball-and-burlap,
or pot size may not be sufficient to support them without tipping or
transferring top movement of the root system. With trees that may be
able to support themselves, plant them and watch the planting hole for
several days after planting. If the tree tips or leans, it needs support."
For landscape
firms unable to watch tree plantings closely, automatic staking can
seem like the best alternative. But Dennis Patton, horticulture agent
with the Johnson County, Kansas, State Research and Extension says automatically
staking and guying is a big mistake.
"Trees
across the country are shamelessly being killed by acts of kindness
or neglect. The culprit is improper staking when the tree is planted
and the failure to remove the mechanisms."
Patton notes that staking problems normally are the result of three
incorrect practices:
- Improper
staking at the time of planting, particularly staking highon
the upper two thirdsof the tree trunk;
- Leaving
braces on past the first growing season;
- Fitting
the stakes too tightly on the trunk to allow for natural growth.
"Staked
trees should be checked often during the growing season to help prevent
this problem. Wire guys that are too tight or left in place for extended
periods will girdle the tree, restricting the movement of nutrients
and water. The tree can be choked to death."
What To Do?
Jim Mancini, vice president of Tree Staple, Inc., has a better idea.
In 1997,
Mancini, who is a landscape professional, was on a job when he devised
the concept of a below-grade tree and shrub stabilizing system that
doesn't need to be removed. He tested the product for four years before
bringing Tree Staple to market. Here's how it works. Guy wire
systems rely on trunk stabilization. Tree Staple stabilizers secure
the tree's root ball.
"Tree
Staple looks like the number seven.' The longer part of
the staple is placed against the outside of the root ball; the cross
member stretches across the top of the root ball, and there's a shorter
prong that goes into the root ball. The product is basically hammered
down on the longer prong until the cross member is slightly recessed
into the root ball and the shorter prong, as well is into the root ball
itself. To adjust, simply alternate back and forth from the longer prong
to the short prong until it's completely in."
Advantages
Over Staking
John King, the company's CEO, says the product has many advantages over
stake and guy wire systems. "Root ball stabilizing puts no restriction
on the trunk of the tree, so there's no risk of chafing, strangulation
or undo stress involved. This allows the tree to grow normally, swaying
in the wind, which everyone agrees allows better development of the
trunk and the tree itself."
Commercial
users are especially drawn to the labor-saving advantages. Tree Staple
stabilizers can be installed in about one minute by one person (versus
the 10 to 20 minutes or more required to install stake and wire) and
requires only a sledgehammer for installation. "This tool is almost
what a power-nailer is to hammering. It involves about one-twentieth
of the time as stake and wire."
There's
more. Because the system is below ground, landscape firms don't need
to return to the site for post-planting maintenance, retrieval or disposal
which saves even more time.
King also
notes that community liability is reduced, because there are no above-ground
obstructions; hence no risk of people or pets being injured by poles
or wires. The system deters random theft, too, since new plantings aren't
so noticeable.
From an
aesthetic standpoint, architects love Tree Staple. "When
architects design projects, they don't design them for stake-and-wire.
They use stake-and-wire only for as long as they must in order to secure
the trees. With Tree Staple, they get instant aesthetic gratification."
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This article
offers an opinion regarding a new concept in tree planting procedures.
Staking
The recommendation for staking trees has changed in recent years as
the result of studies on the effect of wind sway on trees and what happens
to staked trees. Trees tied to tall stakes at a point just below the
crowns are still a common sight, however this practice, that was once
thought to discourage vandalism and support the tree, is no longer recommended.
Trunk stabilizing systems that rely on stakes and/or guy wires require
a considerable amount of time to install properly, need to be adjusted,
and must be removed within 12 to 18 months after installation to prevent
long-term tree damage.
If a tree
is staked and tied just below the crown, the stem cannot sway, and little
increase in stem diameter occurs from base to crown. The stem may in
fact become thicker above the tie than below it, because diameter growth
increases in response to the movement of the crown. A supported tree
will initially gain height faster than the unsupported tree, but the
stem will be thin and weak up to the tie, and then taper rapidly. As
the tree can flex only over the height of the crown, it is all too easy
to snap the crown off by using the tie as a pivot. There are other disadvantages
to staking. Regular maintenance will be needed to check on the ties,
as these can abrade and even strangle the stem if not adjusted from
time to time. Stakes and ties also cost money. Where possible, it is
usually better to use smaller trees that do not need staking. Furthermore,
nursery grown trees have a relatively limited root-spread that makes
them vulnerable to wind-throw or vandalism when they are planted in
cultivated soil.
The stem
diameter growth of a tree is stimulated when it sways in the wind. If
a tree is left unstaked, the whole tree, including the stem, will sway,
stimulating maximum diameter growth at or near the root collar. Over
time, this swaying will help form a stout, firm tree with a stem that
tapers evenly from base to crown. The unstaked tree will thus develop
a structure that can flex under the force of wind or vandalism. As roots
at the root collar also increase in diameter from the movement of the
stem, the tree is given added stability.
Stapling
A new, below-grade system that secures new plantings by the root-ball
has been designed to be left alone. The concept is simple. A long "staple"
is placed through the root ball to hold the ball in contact with the
bottom of the planting pit and hold the root system in place. One person
using a simple sledge hammer can install the product in less than 2
minutes; significantly less than the time it takes for traditional guying
and staking methods.
It's what
you can't see that is a key benefit of below-grade stabilizers. There
are no above ground stakes, wires, or exposed components, whatsoever.
Immediately upon installation, the staple stabilizes the tree to provide
a finished look to a new landscape. And if the aesthetics alone are
not enough of an enticement, think in terms of safety for children or
pets where the danger of exposed stakes and wires is eliminated. The
faster installation, no maintenance, better appearance, and reduced
liability are all benefits to this new concept.
This new
invention was developed by Jim Mancini, a veteran landscaper, who has
patented this innovative way to stabilize newly planted trees. His company,
Tree Staple, Inc.
Sells the new below-grade stabilizing system under
the Tree Staple brand. The product and its concept have captured
the interest of the ANLA who is encouraging all municipalities, landscape
architects, state governments and landscape installers to consider alternatives
to traditional staking and guying specifications.
The ANLA
recommendations refer to research that proves that trunk stabilization
may be detrimental to a tree's growth and development. Trees need natural
movement to grow properly. Traditional trunk stabilizing creates unnatural
stress and wears on the tree's trunk. When secured by the root-ball,
trees flex from the root collar through the length of the trunk. They
develop a better overall taper and become more tolerant of wind and
vandalism. Trunk damage and girdling are inherent dangers of traditional
systems that use guy wires. The tree staple system eliminates these
problems and promotes better growth.
References:
ANLA Memorandum, W. Quinn; "Should Newly Planted Trees Be Staked
and Tied?" FNR-FAQ-6, Dept. of Forestry and Natural Resources, Purdue
University Extension Service, June 21, 2002.
British Trust for Conservation Volunteers, "Tree Planting and Aftercare",
www.btcv.org/skills
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