The Top 10 Myths of Tree Care
For Immediate Release
For Further Information Contact Sonia Garth:
(217) 355-9411 Ext 217
Top 10 Myths of Tree Care
CHAMPAIGN, IL- Should you prune your trees in the Spring? How deep must fertilizer be applied to reach the roots of your trees? Which species of trees should be topped to keep them from falling on your house? Most homeowners treasure the trees on their property but know little about how to care for them. Much of what you may have heard about tree care is actually incorrect, based on myths and misconceptions. Here are the top 10 myths of tree care.
MYTH #1: When a tree is planted it should be securely staked to
ensure the development of a stable root system and a strong trunk. Although
it is sometimes necessary to stake trees to keep them upright and allow
establishment, there are some adverse effects of staking. Compared to staked
trees, unstaked trees tend to develop a more extensive root system and better
trunk taper. Allowing a small amount of movement can help root and trunk
development. Of course, the worst effect of staking is the possibility of trunk
damage from the staking wires or ties. Staking materials usually should be
removed after one year to avoid "girdling" the tree.
MYTH #2: Newly planted trees should have their trunks wrapped with
tree wrap to prevent sunscald and insect entry. Studies using most
common tree wraps have shown that they do not prevent extreme fluctuations in
temperature on the bark. In some cases, the temperature extremes are worse.
Also, tree wraps have proven quite ineffective in preventing insect entry. In
fact, some insects like to burrow under it.
MYTH #3: Trees should be pruned back heavily when they are planted
to compensate for the loss of roots.Tree establishment is best with
unpruned trees. Although pruning the top can reduce the amount of water that
evaporates from the leaves, the tree needs a full crown to produce the
much-needed food and the plant hormones that induce root growth. The tree will
develop a stronger, more extensive root system if it has a fuller crown. Limit
pruning at the time of planting to structural training and the removal of
damaged branches.
MYTH #4: When removing a branch from a tree, the final cut should be
flush with the stem to optimize healing. First of all, trees don't
"heal" in the sense that wounds on people heal. Our bodies regenerate tissues
in much the same form of the tissues that were removed (to a limited extent).
Trees compartmentalize wounds, generating woundwood over the wounded area.
Flush cutting removes the "branch collar," creating a larger wound than if the
branch were removed outside the collar. Also, it is likely that some of the
parent branch tissue will be removed. The spread of decay inside the tree is
greater with flush cuts.
MYTH #5: Pruning wounds greater than three inches in diameter should
be painted with a wound dressing. Research has shown that the common
wound dressings do not inhibit decay, do not prevent insect entry, and do not
bring about faster wound closure. In fact, many of the commonly used dressings
slow wound closure.
MYTH #6: Certain fast-growing, weak-wooded trees such as silver
maple and Siberian elm should be "topped" to make them less hazardous in the
landscape. While topping these trees may reduce the potential hazard at
first, they will likely be more dangerous in the future. Topping stimulates
growth of twigs below the cuts. Growth of many, vigorous shoots leads to
branches with weak attachments. Also decay spreads inside the stubs and
branches that were topped. Within 2-5 years after topping, the tree will have
regained its height, but will be more hazardous than before the topping.
Besides, topping makes trees ugly. Alternatives to topping include thinning,
cabling, or removal and replacement with a more suitable species.
MYTH #7: If certain species of trees are pruned early in the spring,
they will "bleed," stressing the tree and causing health problems. True,
some trees such as maples and birches will "bleed" or lose sap from pruning
cuts made early in the spring. This bleeding does not hurt the tree, and the
loss of sap is inconsequential. With a few exceptions, most routine pruning can
be done anytime of year. The worst time is just as the tree has leafed out in
the spring. The best time is when the tree is dormant. To maximize flowering
for the following year, prune just after bloom this year.
MYTH #8: The root system of a tree is a mirror image of the top.
Many people envision a large, branching taproot growing deep into the soil.
Actually, taproots are very uncommon in mature trees. If taproots do develop,
they usually will be forced into horizontal growth when they encounter hard
subsoils beneath the surface. The entire root systems of most trees can be
found within three feet of soil. The spread of the root system however, can be
very extensive, often extending 2-3 times the spread of the crown.
MYTH #9: Trees require "deep root fertilization" to reach their root
system. In most U.S. soils, the vast majority of trees' fibrous,
absorbing roots are in the top eight inches of soil. Roots grow where
conditions are best for root growth, where water and oxygen are available. When
we place fertilizer 12" - 18" deep in the soil, we are putting it too deep.
MYTH #10: When a tree has lost a significant portion of its root
system such as in construction damage, the crown should be cut back to
compensate for root loss. While this is a common recommendation,
research has not supported it. Following root loss, unpruned trees seem to
respond better than pruned trees. Obviously, any removal of branches will
reduce the capacity of the tree to produce food in the leaves. Although the
tree will probably lose some branches as a result of the root damage (if the
tree survives the trauma), it is best to let the tree decide which ones. Thus,
pruning should be limited to hazard reduction at first. Later, after the tree
has responded to the damage, further pruning would be in order.
Get advice from an arborist- An arborist is a professional
in the care of trees. A qualified arborist can give you sound advice and can
provide the services your trees may need. Good arborists will perform only
accepted practices. When choosing an arborist, look for ISA Certification,
membership in professional associations, and ask for proof of insurance. Be
weary of individuals who go door-to-door offering bargains for doing tree work.
Don't be afraid to check references.
Be an informed consumer- One of the best ways to be assured
you are making wise decisions regarding your trees is to educate your self on
some of the basic principles of tree care. The International Society of
Arboriculture offers a number of brochures designed to inform consumers about
trees. For a free set, write to ISA at P.O. Box 3129, Champaign, IL 61826.
The International Society of Arboriculture (ISA) is a nonprofit
organization supporting tree care research around the world. Headquartered in
Champaign, Ill., ISA is dedicated to the care and preservation of shade and
ornamental trees. For more information contact a local ISA certified arborist
or visit www.isa-arbor.com