Removing trees and shrubs
Removing trees and shrubs becomes necessary when the plants are severely injured by storms, when they outgrow their sites or when they become maintenance problems.
Large trees are best removed by professional tree services. Their employees have the proper equipment and training to fell trees safely and avoid damaging property. Most cities require licensing of tree services; homeowners are required to select from licensed companies. Call your city hall for a list of licensed tree services. Before authorizing any work, check the company's service record with your local Better Business Bureau. Ask the tree service for proof of insurance. Also, ask neighbors and friends for recommendations, and check references the tree service furnishes.
Once a tree is removed, its stump may be ground out, pulled, or left alone. You must specify the depth to which you wish the stump ground, as tree services may not automatically dig the stump out adequately. Grind the stump out to a depth of 12 inches if the area is to be sodded. If the tree was large with a massive stump and another tree is to be planted nearby, grind the stump deeply enough to remove most, if not all of it.
Soil type also plays a role in grinding depth. Trees growing in sandy loam soil have quite extensive and vigorous root systems. Root systems are more restricted in soils with hardpan clay a few feet beneath the surface.
Mushrooms and other fungi that feed on decaying organic matter in the soil may become a temporary problem until roots and large concentrations of wood chips have thoroughly broken down. Microorganisms that feed on decaying wood need nitrogen to help them decompose the wood. They compete with roots of nearby plants for nitrogen. Monitor replacement plants for signs of nitrogen deficiency and fertilize them if necessary.
When stumps are ground out, collect as many of the wood chips as possible for use as mulch around trees and shrubs. Wood chips from the deeper part of the stump are heavily mixed with soil and don't make an attractive mulch. Compost them for future use in garden beds. Wood chips from trees diagnosed with Verticillium Wilt disease should be composted before being used as a mulch.
If a tree has been dead for a long time, its replacement may be planted as close as 6 to 8 feet from the old trunk. (Uneven areas in the lawn near the old tree stump result from the total decomposition of large lateral roots and indicate the tree has been dead for a long time.) You may also use this close spacing if replacing a newly removed, healthy tree. When replacing a diseased tree, use a variety that is resistant to the disease that killed its predecessor. Some diseases persist in the soil for decades.
Grinding has replaced pulling stumps in urban areas. If a stump is to be pulled, leave a foot or more of the tree trunk intact so a chain can be wrapped around it and hooked to a tractor or truck with adequate horsepower to pull it out.
Stumps rot over a number of years without special treatment. You can accelerate the process by covering a stump with a few inches of soil and keeping it moist. There are also chemical stump removers but label directions often include burning the stump. This is usually not legal in metropolitan areas.
New shoots that sucker up from the stump can be snipped off as soon as they appear. Or you can spray or paint them with a woody brush killer containing the active ingredient triclopyr. An herbicide containing glyphosate, often sold as Roundup, is also effective on some woody plants. Triclopyr and glyphosate are systemic herbicides, which means they travel internally throughout the plant's vascular system. Make sure to dilute these herbicide products before spraying them onto foliage. Undiluted product will burn leaves but not move into the vascular tissue, so they're a waste of time and money.
If you are trying to preserve the best of several suckers from the same stump, do not apply herbicide as you will kill all of them. Just cut the unwanted suckers off with pruning shears. Most tree stumps will cease to sucker after a year or two.
Some trees, such as poplar, spread by means of suckers that arise from their roots. Suckering from these trees is actually more profuse once the parent tree is removed. Because poplar suckers originate from a common parent plant, they share a vascular system. Herbicides cannot be used to kill only one of a group.
When the same kinds of trees grow close together, their roots cross underground and fuse. The vascular systems of the trees are then shared and any herbicide applied to one may injure or even kill the other, if herbicide is drawn up across the root graft.
The best way to avoid herbicide injury to trees that share a vascular system is to sever the roots so herbicide can't travel. This is best done by professionals with experience using a vibratory plow, a machine that slices the soil deeply around the trees to be removed.
Some shrubs, such as sumac, also spread from suckers. If you treat the suckers with a woody brush killer, you may kill the entire planting. Suckering can be controlled on a number of woody plants by applying plant growth regulators such chloflurecol-methyl (Maintain-A) or naphthalene acetic acid (Tre Hold) to pruning cuts on the stems. This will help control the size of the planted area but not kill the plants. These materials are available in garden centers. Be sure to read and follow label directions carefully.
Many suckering shrubs can be killed using an herbicide containing triclopyr. Spray the foliage once the shrubs are fully leafed out. A brush killer sprayed on the foliage, trunks and branches will cause wilting in 2 to 6 weeks. Be sure to follow the label directions explicitly.
Shrub stumps can be ground out if necessary. Some tree services have small, portable grinders which can be used alongside homes and in small spaces. Small shrubs can be dug out of the ground by hand. Shrubs can also be pulled out using a winch or suitable vehicle. Leave enough of the stems to wrap a chain around or to serve as handles if they are dug out by hand.
H446R Reviewed 10/98
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