Most homeowners treasure the trees on their property but know little about how to care for them. However, much of what people may have heard about tree care is actually incorrect, based on myths and misconceptions. Here are some top myths of tree care, according to the International Society of Arboriculture:
MYTH: When a tree is planted, it should be securely staked to ensure the development of a stable root system and a strong trunk. Actually, unstaked trees tend to develop a more extensive root system and a better trunk taper than staked ones. A small amount of movement can help root and trunk development. Staking wires or ties can also cause trunk damage. It's important for staking materials to be removed after one year to avoid "girdling" the tree.
MYTH: Newly planted trees should have their trunks wrapped with tree wrap to prevent sun scald and insect entry. Studies have shown that tree wraps 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: Trees should be pruned heavily when they are planted to compensate for the loss of roots. Although pruning can reduce the amount of water that evaporates from the leaves, the tree needs a full crown to produce the much-needed food and plant hormones that induce root growth. The tree will develop a stronger, more extensive root system if it has a fuller crown. At the time of planting, limit pruning to structural training and the removal of damaged branches.
MYTH: When removing a branch from a tree, the final cut should be flush with the stem to optimize healing. Trees compartmentalize wounds, generating woundwood over the wounded area. Flush cutting removes the "branch collar," creating a larger wound and decay inside the tree than if the branch were removed outside the collar.
MYTH: Certain fast-growing, weak-wooded trees, such as silver maple and Siberian elm, should be "topped" to make them less hazardous in the landscape. 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 regain its height, but will be more hazardous than before. Topping also makes trees unattractive.
MYTH: If certain species of trees are pruned early in the spring, they will "bleed," stressing the tree and causing health problems. Some trees, such as maples and birches, "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 any time of year.
MYTH: 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 uncommon in mature trees. If taproots do develop, they are usually forced into horizontal growth when they encounter hard subsoils beneath the surface. The root systems of most trees can be found within 3 feet of soil. However, the spread of the root system can be very prolific, often extending two to three times the spread of the crown.
MYTH: Trees require "deep root fertilization" to reach their root system. In most U.S. soils, the majority of trees' fibrous, absorbing roots are in the top 8 inches of soil. When we place fertilizer 12 inches to 18 inches into the soil, we are putting it too deep.
If you are unsure of proper tree care, consult an arborist - a professional in the care of trees. When choosing an arborist, look for ISA Certification, membership in professional associations, and ask for proof of insurance. Be wary of individuals who go door-to-door offering bargains for doing tree work. Don't be afraid to check references.
The International Society of Arboriculture offers consumer information about trees at www.treesaregood.com. Or, to contact a local ISA certified arborist in your area, visit www.isa-arbor.com.