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 seven myths of tree care according to the International Society of Arboriculture:
MYTH #1: When a tree is planted it should be securely staked.
Fact: Although it is sometimes necessary to stake trees to keep them upright and allow establishment, there are some adverse effects of staking. 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.
Fact: Studies using most common tree wraps have shown that they do not prevent extreme fluctuations in temperature on the bark which cause sunscald. In some cases, the temperature extremes are worse. And tree wraps have also proven quite ineffective in preventing insect entry. In fact, some insects like to burrow under it. However, wrapping may protect your trees from injury from animals gnawing or rubbing against it, but should always be removed before it begins girdling the tree.
MYTH #3: Trees should be pruned back heavily to compensate for the loss of roots.
Fact: Trees can lose roots during the planting process or when construction and other activities go on around them. 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. Or, if your tree has survived trauma from construction or other damage, it is best to let the tree decide which branches it is going to lose. Pruning should be limited to hazard reduction at first. Later, after the tree has responded to the damage, further pruning would be in order.
MYTH #4: When removing a branch from a tree, the final cut should be flush with the stem to optimize healing.
Fact: First of all, trees don’t “heal” in the sense that wounds on people heal. 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: Certain fast-growing, weak-wooded trees should be “topped” to make them less hazardous in the landscape.
Fact: 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 two to five 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 #6: If trees are pruned in early spring, they will “bleed,” stressing the tree and causing health problems.
Fact: True, some trees such as maples and birches will “bleed” or lose sap from pruning cuts made during early 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 any time 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 #7: The root system of a tree is a mirror image of the top.
Fact: 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 two to three times the spread of the crown. This means you don’t need to perform “deep root fertilization” to reach their root system-most of the trees’ fibrous, absorbing roots are in the top eight inches of soil.
Get advice from an arborist. When choosing an arborist, look for ISA Certification and membership in professional associations. Ask for proof of insurance, too. Be wary of individuals who go door-to-door offering bargains for doing tree work. Don’t be afraid to check references. To find an ISA Certified Arborist, along with more tree care information, visit www.treesaregood.org.