Beautiful, large trees are often what attracts potential buyers to home sites. Years after the construction’s finished, though, these owners may begin noticing that the trees around which they built their home are declining and dying. That’s when they call me, a Board Certified Master Arborist (BCMA).
The time for that call was when they were first considering that site. Tree protection should’ve begun long before the first shovel of dirt was turned. Trees may be the largest living organisms on earth but they’re still sensitive to environmental changes, especially the upheaval and trauma that construction can cause.
Like all aspects of a construction project, tree preservation should begin with a plan. That plan should address all risks the tree(s) can be subjected to on the construction site and steps to prevent damage. Your consulting arborist is the most qualified person to write that plan. Then it should be presented to the owner, architect, building contractor and landscape contractor for review. If any of them can’t work within the plan, even after negotiating any tweaks or modifications that can be made without endangering the trees, my best advice is to search for replacements who can work within the plan.
The first step in implementing the plan should for the owner, arborist and architect to walk the property. At this time, select the trees that you prefer be saved and those you’d like saved if possible. The arborist should then inspect these trees to be sure they’re sound and healthy. If any on the “must save” list aren’t safe to keep, they should slated for removal.
The architect should then sketch the house’s footprint on the plot plan and the arborist check it to be sure that the home’s orientation won’t cause changes, such as adversely changing the light or wind pattern. This could result in the wrong tree in the wrong place, and a stressed tree can become the target for insect and diseases. It will then be a liability rather than an asset. This problem may be eliminated by just changing the house’s orientation slightly.
Before the first builders enter the property, an area around the base of the tree should be fenced off with bright colored material. The critical root zone (CRZ) for the fencing is one foot out from the trunk for every inch of trunk diameter. Penalties for contractors and others who violate this area with people, building materials or vehicles should be written into the contract.
Heavy weights in the CRZ compacts the soil, reducing the amount of water and air that can reach the roots. Stacking building materials and parking vehicles in the CRZ can also break branches and damage bark. The resulting tree health problems may not become apparent for several years.
Changing the grade near the trees even a few inches can disrupt their life functions. If there’s no choice but to change the grade, it’ll be necessary to build a retaining wall if you’re lowering the grade and a tree well where the fence is if you’re raising the grade. One more precaution: Don’t let the contractors running your utility lines to the house trench inside the fence. They’ll sever roots. Insist that they drill. That’ll move the roots out of the way, rather than sever them.
Trees may be the largest organisms on earth, but they don’t fare very well when the status quo is disturbed. You paid a premium for the lot because of these trees that were there long before you, and retaining a qualified arborist for your team and following the advice presented here will help to assure that those trees will be healthy and magnificent long after you’re gone.