construction | Gardening in the Panhandle

New Home Construction and Impacts of Existing Plants

by Stephen Greer | May 27, 2021

As we have all observed communities are growing in the Panhandle through new home construction or through renovation of existing properties. This article will address new home construction. Many questions come to mind as construction begins with some of these questions needing to be addressed prior to start of construction. Determining impacts on the plant resources that already exist on the site should be included in the planning, design, construction and post-construction phases to be successful in achieving a healthy vibrant landscape for all to enjoy.

Photo Courtesy: Stephen Greer

Homes in community developments are being located on smaller lots in groups with conservation areas saved for the open spaces for all to enjoy. An older term for this was new urbanism and now is often referred to as conservation or clustered development. This type of development identifies and encourages environmentally friendly habitats for plants and animals creating a biodiversity within a walkable neighborhood designed to protect yet allow residence to enjoy some of the Northwest Florida beauty.

How can the objectives of building the new home desired, manage to protect the healthy plants already existing on the site? These challenges are difficult to answer but there are steps to accomplish both. For this article I will address construction and tree protection.

Protecting existing trees during the construction and post-construction phases takes expertise and a plan. First, consider hiring a professional arborist or urban forester to assist in this plan development. Understanding the existing trees on site prior to construction from the variety, location, visual impacts, size, overall health and location on the property are a good start. How do you protect the selected trees? First identify the trees that will need to be removed. Look for unhealthy stressed trees, significant limb death already occurring, poor crown growth (thinning) and other observations.

Photo Courtesy: Stephen Greer

The next step is to make a sight plan that needs to include grading needs for the home, drainage on the property, existing trees and surrounding vegetation, property lines, set back requirements, driveway location, utility placements and site of home. Flag trees that will be impacted and will need to be removed during the construction.

Following the sight plan, a tree protection plan needs to occur. This must happen before construction begins and include all parties involved to make sure all are in agreement. This is the stage where the group can identify conflicts involving tree protection and construction. Oversight by the owner, contractor and equipment operators is critical. A tree protection zone must be identified and implemented before construction. This typically involves setting up a fence around the protected trees and vegetation to restrict access of equipment and potential damage to the root system. A rule of thumb is to maintain a radius of at least 1.25 feet of protected area for each 1 inch of tree trunk diameter. An example would be a 12-inch diameter tree trunk with good protection at 15 feet to best protection at 30 feet of radius.

Photo Courtesy: Stephen Greer

The point is to give the best chance of a health survival of the tree during this soil and site disturbance as the construction process progress all the way to post construction with the removal of the protective fencing. Difficult decisions may need to be made of selecting trees to protect but will be needed. Enjoy the successes and plan for creating a new landscape that includes part of conserving plants that were there before and going forward.

Leaving the Tree Isn’t Saving the Tree

by Sheila Dunning | May 19, 2016

As cities expand, wooded lands and property with mature trees are being developed into commercial and residential sites. Unfortunately, the construction process can be deadly to nearby trees. In most cases, the trees don’t die immediately. Several years later as symptom development occurs in the declining trees, most people don’t associate it with the previous construction.

However, it is possible to preserve trees on building sites if the right measures are taken. Trees and their root systems must be protected from damage during the construction process. Roots absorb the water and nutrients that are essential to tree health. Damage to the roots can lead to the death of a tree. Compaction of the soil from equipment operation can hinder the tree’s absorption of nutrients.

The single most important action is to set up sturdy construction fences around the tree. The fence should be placed at least at the dripline of the tree’s canopy. As a general guideline, allow 1 foot from the trunk for each inch of the trunk diameter. Even with this method, 50% or more of the roots will be impacted by construction. No vehicles, building materials, waste, or soil should be allowed within the fenced area. No digging, trenching, or soil disturbance should be performed in that space. If construction equipment is allowed to operate close to the fencing, root pruning should be performed. A 4-5 inch deep trench should be dug on the outside of the tree protection zone with an air spade and then cut the roots cleanly with a saw. This root pruning technique will limit extensive damage to the roots.

The next step that will help the survival of a protected tree is irrigation during the construction phase. Stressed trees need plenty of water throughout the process. This means watering each tree about 2-3 times per week to a soil depth of 4-6 inches. Additionally, an application of 3 inches of organic mulch within the tree protection zone would help maintain soil moisture. But, do not place mulch against tree trunks because it could cause fungus growth to the trunk. If roots are not pruned at the edge of the protection zone, mulch should be placed over any roots that could possibly be driven over to reduce compaction.

Following construction the fencing can be removed, but irrigation needs to continue. However, the frequency should be reduced while the duration needs to be increased, to ensure that the tree receives enough water to maintain moisture in the top 12-18 inches of soil for the next year.

Simply keeping a tree on site does not mean it will survive the construction process. If measures to protect the tree cannot be taken, the most practical approach is to remove the tree prior to construction. But, for some of the historical mature trees it is probably worth the effort to preserve some horticultural heritage of the area.