Tree Preservation

We just bought a tree-covered lot on which to build a new home. What can Exterior Worlds tell us about tree preservation?
We always remind our clients that trees are more delicate than most people realize and, unfortunately, construction kills a lot of them. Because trees are large organisms, it takes a while for them to die. Five years or more can pass before they finally do die and by then your builder is long gone. Their chances for survival are much greater with a little TLC.

What can be done to save the trees we want during construction?
We see three main offenders when it comes to the survival of trees during construction:

• Soil compaction. The main killer of trees during and after construction is soil compaction. The most common, yet overlooked, cause of compaction is foot traffic—in fact, compaction from foot traffic is the main killer of trees on a construction site. Additional soil compaction occurs when construction vehicles drive over the root zone and when construction materials are set down on the roots. If soil is piled onto the root zone that also compacts the soil and suffocates the tree by cutting off the exchange of gases in and out of the soil.
• Root damage. Root damage usually happens when digging for foundations, swimming pools, landscaping, irrigation systems, drainage systems and landscape lighting.
• Soil contamination. Soil contamination is normally due to construction materials, such as paint, turpentine, lime, cement, or acid, leaching into the soil.

What tree preservation method can builders use during construction?
Preconstruction:
One tree-saving action is to fence off the root zone to force traffic and storage away from the trees. Trees also benefit from deep root fertilization prior to construction so that they have as much nutrition as possible during building. If you know a tree’s roots will be cut or damaged due to the construction, have the roots trimmed beforehand. This measure is much less stressful on the trees than having the roots ripped and torn. Paths and bridges made of eco-friendly materials reduce the impact of the construction. Sometimes a temporary irrigation system is installed, especially if construction is expected to go on for a year or so.

Construction:
Hand-digging for utilities, electrical, plumbing and irrigation systems goes a long way in tree preservation efforts. Compressed air can be used to blast the soil away from tree roots. It allows contractors to see the roots and run underground conduits without cutting them. During construction, root barriers can be used to prevent damage due to installing new conduits for hardscapes, such as outdoor water fountains and outdoor kitchens.

How can Exterior Worlds help us after construction?
After construction, we suggest another deep root fertilization to ensure health. We also advise that trees be inspected and treated for insect infestations. Insects can kill really quickly when Houston’s weather turns hot and the trees are stressed from construction. Aeration is another important tool in tree preservation as it promotes root growth and combats compaction.