Tree Preservation Education For Builders and Developers in Charlotte, North Carolina

Tree Value

Trees have value for aesthetics, shade, noise reduction, control of wind and water erosion, reduction of air pollution, defining space, screening objectionable views, providing privacy and other benefits. Trees also add monetary value to real estate. Although trees are not without problems, their presence usually results in quicker and higher priced sales for real property. We give an example of a large white oak in front of a local bank buiding and use a tree evaluation formula to demonstrate the value added to the property by that tree. We also show the visual impact trees make on basically the same type of house without trees. Lastly, we discuss the potential for energy conservation in heating and cooling created by having trees around a building.

Tree physiology

Under this section we diagrammatically show the functions of tree roots (feeder and the supporting and conducting ones), xylem, phloem, cambium, and leaves, plus the extent of tree roots, and the movement of nutrients, water, and manufactured food materials.

This is followed by a discussion of a soil profile and its relation to rooting habits. We note how changes in environment, from natural to landscaped conditions, as well as soil compaction affect the growth and functioning of trees. Also, at this point we emphasize how destroying large roots really destroys many miles of feeding roots which are necessary to the continued health of the trees.

Preventing andcorrecting construction damage

This section, the longest one of the program, is really a potpourri of types of damage, their prevention and correction. Although damage to trunk and limbs is covered, major emphasis is placed on root damage and how to prevent it.

First, we talk about how to and how not to prune broken, dead or interfering limbs. We show the proper types of tools and the proper technique to be utilized. The reasons for the recommended procedure is explained in terms of the tree physiology that has already been covered.

The second item of business is bark damage and its ultimate result, and if not treated, rotten cavities. Again, proper tools, techniques, and physiological reasons are emphasized.

Root damage, its consequences, prevention, and reduction, is the next and the most important part of the whole program. We begin with a review of root distribution and extent which is followed by explaining how certain construction activities intrude upon that root system. This type of information is intermixed with showing how proper barricading can protect the root systems and thus the trees, both singly and in groups. We also point out how retaining walls, when properly built, may save trees that would otherwise be lost to grade changes.

Another aspect of the root damage problem that builders tend to overlook is the damage underground which appears to be solved when backfilling is completed, e.g. construction of storm drains, curbing, sewer lines, watermains, etc. The ultimate consequence of this type of work, particularly in the Charlotte area, is the invasion of the untreated root system by rootrotting fungi, especially the Polyporus group. Once this happens, there isn’t much hope of saving a tree.

Another critical issue we cover in regard to roots is the matter of filling over them. We illustrate how to install an adequate drainage system prior to filling so the trees can have a good chance of surviving the construction.

The compaction of soil over tree roots is our next concern. We not only talk about the compaction caused by heavy equipment and material storage but also discuss the effect of pH alteration which may result from such things as discarding concrete next to a tree.

As a final subject in this section, we stress the need for tree fertilization following construction activity in order to stimulate feeder root production for overcoming some of the damage.

Tree removal during construction

An unusual aspect of our program is the stressing of poor tree risk removals prior to construction. Trees in poor health and/or condition are examples. The major emphasis, however, is on the removal of certain species, which, when in weakened condition, are very prone to attacks by pests and diseases that are difficult to control. The two species groups in our area that fit this description are the hard pines (Southern pine beetle) and elms (Dutch elm disease). Recognition of these problems is covered as well.

Tree planting

The important procedures involved in successful tree planting are discussed to encourage the planting of more desirable species on the new home sites. Presently, silver maple is the most popular tree to plant for the builders. We give reasons for not planting it, besides covering a number of species and varieties that do well in our area. We also try to point out how to avoid some of the pitfalls involved in the actual planting techniques and the species selection for the sites involved.

Damage to streettrees

In this last unit, primarily for the public sector, we show what happens if care is not taken in working around street trees, such things as using backhoes up against tree trunks and severe root cutting for curb and sidewalk replacement. All of these items lead to basal and/or root rot with the subsequent premature loss of the trees. The end result is often property damage or even loss of life.

In conclusion, we in Charlotte feel that the most positive way to regulate tree problems, both public and private, is first by education, and second, by reasonable and practical regulation. Our ultimate goal is to have all who work around trees to be aware of their value to our City and how to exercise proper care in preserving them.