Like a voice of warning, the recent snowstorms made a crashing statement for the need for good tree care.
One voice that has been leading the chorus for good tree care is Tony Dietz, urban forestry coordinator for the Utah Division of Forestry, Fire and State Lands. He has preached good tree care principles in his 29 years with the agency. His mission is to educate professionals and homeowners on how to care for their trees.
The storm that broke the trees and knocked down the power lines is not unusual. Early storms spell disaster when they drop wet snow that hangs on leaves that are still on the trees. As bad as that combination is, it is made much worse by a tree-destroying practice called topping.
Topping is indiscriminate cutting back of tree branches or trunks to stubs or lateral branches that are not big enough to be central leaders or trunks. Other names for topping include "heading," "tipping," "hat-racking" and "rounding over." Whatever the name, the practice destroys trees.
Many trees that came down and knocked out power lines in this recent storm had been topped. This process makes them weak, and they are easily broken. The irony of the topping scenario is that most people mistakenly believe that topping will reduce the storm hazard of falling branches. In fact, it has the opposite effect. Topped trees are potential liabilities.
Topping is an unacceptable pruning practice without any scientific basis. Any damage caused by branches failing from a topped tree could lead to a negligence suit.
According to Dietz, people think topping trees makes them grow better.
"When trees shoot up dozens of new shoots around the topping cut, they are going into survival mode. This comes at great expense to the tree," he said. "The shoots develop from buds near the surface of the old branches. Unlike normal branches that are joined to the continuous wood of strong trunks and branches, these new shoots are only anchored in the outermost layers of the parent branches."
The new shoots grow as much as 20 feet in one year in some species, he said. Unfortunately, the shoots are prone to breaking during snowy, icy or windy conditions. The irony is that while the goal was to reduce the tree's height to make it safer, topping makes it more hazardous.
Another topping problem is tree decay. The preferred place to make a pruning cut is just beyond the branch collar at a 45- to 60-degree angle to the branch bark ridge. Leave the branch collar intact to help prevent decay from entering the trunk. These thinning cuts stimulate growth throughout the tree and discourage water sprout development.
The tree can close a wound made there if it is not too large. Cuts made along limbs, between lateral branches, create stubs with wounds that the trees are not able to close. The exposed wood tissues begin to decay.
Normally a tree "walls off" or compartmentalize the decaying tissues. Most trees cannot ever close the severe wounds left by topping. Decay organisms are then free to move down through the branches.
Dietz points out that topping stresses trees because it removes 50 to 100 percent of the leaf-bearing crown of a tree. Since the leaves are the "food factories" of a tree, this starves a tree. The severe pruning triggers a survival mechanism. The tree activates latent buds, forcing rapid growth of multiple shoots below each cut. Trees must put out a new crop of leaves as soon as possible. If a tree does not have the stored energy reserves to do this, it is seriously weakened and may die.
Dietz admits he is not certain why this practice is so widespread in the state. As someone who grew up and was educated in Indiana and Illinois, he seldom saw the trees there being treated this way. His theory is that many people in Utah are used to the desert, not to trees that grow higher than the house.
"I often hear the people remark that their trees are out of control, that they are growing way too tall and they are likely to fall down. They want to get them down where they can reach them."
Dietz suspects the practice got started a hundred years ago. "Thirty or 40 years ago people thought if it was good enough for Dad and good enough for Grandpa, it is good enough for me. The practice of cutting the trees off at the top continued and even got worse."
Another problem, he says, was that the power company uniformly cut the trees below the power lines. Everyone figured if the power company did it, then they should, too. Utilities have stopped this kind of pruning, but it still persists and continues to destroy trees.
A stressed tree is more vulnerable to insect and disease infestations. Large, open pruning wounds expose the sapwood and heartwood to attack.
The tree may lack sufficient energy to close wounds and defend them against an invasion.
The problem is also one of aesthetics. Topping, simply put, makes trees ugly. Trees have beautiful, natural branching structures that are biological wonders. Their wonderful variety of shapes and growth habits display their leaves to the sun. Topping removes trunks and branches, leaving ugly stubs.
Topping destroys the natural tree form. In temperate climates from November through March, there are no leaves on the tree. Without leaves, a topped tree shows its disfigured and mutilated skeleton. With the leaves, it is a dense ball of foliage that does not show its true beauty or shape. Once a tree has been topped, it can never fully regain its natural form.
Dietz also points out that the cost of topping a tree is not limited to what you pay to have it done. "Topped trees will require pruning again within a few years," he said. "The only choice is to cut them down again or clean up after them when a storm breaks them down. This is often very expensive. Trees often die after they are topped, and if the tree dies it must be removed."
Taking out trees is often a very expensive operation. Another problem is the reduction in property values. Healthy, well-maintained trees add 10 percent to 20 percent to the value of a property. Disfigured, topped trees can reduce property values and are considered liabilities.
"If you must prune a large tree, hire a certified arborist," said Dietz. "Every year individuals are killed trying to prune large trees. Many are killed by contacting live electrical wires. An arborist can determine what type of pruning is necessary to improve the health, appearance and safety of your trees. A professional arborist can provide the services of a trained crew, with all of the required safety equipment and liability insurance."
When selecting an arborist, look for these qualifications. Never let anyone prune your trees without proof of liability and workers compensation insurance. Select those who are members in professional organizations such as the International Society of Arboriculture (ISA), the National Arborist Association or the American Society of Consulting Arborists. Competent arborists are happy to provide references if asked.
"Avoid using the services of any tree company that advertises topping as part of its service," said Dietz. "Knowledgeable arborists know topping is harmful to trees and don't practice it."
Have a gardening question? E-mail it to us at features@desnews.com (subject Larry Sagers) and we'll forward it to Larry for his consideration for a future column.