Construction of an in-ground can have severe and often long-lasting negative effects on trees. To minimize stress and long-term damage, protecting trees before construction begins and continuing throughout the entire process is generally necessary. Although there are many things to consider, we always start with the most important factor: how close are the trees to the pool and where will the crews be entering the yard for the duration of the construction process?
Location
Trees need to be a minimum of 2½ times the trunk diameter away from the lip of the pool to be within the threshold of safety with respect to anchoring roots. Trenching can only occur a certain distance from the trunk without not only compromising the overall health of the tree, but also compromising the tree’s ability to hold itself up.
Equipment access and usage
Another important factor not always considered is the access to the backyard for the heavy equipment and construction crews. Often crews don’t keep to only one access point, or pick access through wooded areas when other pathways to the back yard are readily available. Compaction to the root zones of existing trees often not associated with the pool itself can occur when moving equipment and crews to and from the back yard.
Often, tall backhoes damage trees when moving them into and out of the construction area. Backhoe width, height and access needs to be closely scrutinized with respect to tree limb and trunk damage. If tree limbs need to be removed in order to get the backhoe into the back yard, it should be done before damage occurs. Broken limbs from heavy equipment damage can often cause major wounds to trees that cannot be repaired.
Tree types and resiliency
Certain native species, such as live oaks, are often more resilient and resistant to construction stress than other species. Knowing this, it is also important to identify the species the pool will surround and the crew is working around and the overall health of the tree(s) in question. For example, you would probably would not want to build a pool around a large hackberry tree. Hackberry trees are prone to splitting when they are sizeable, are not considered to be very long-lived trees, and can be quite damaging when these heavy limbs fall.
Installation time
Time of year can also be very important when scheduling pool installations. For maximum survivability, often a winter as opposed to a summer pool installation can be the difference between life and death for affected trees. Summer heat stress certainly takes its toll on trees, and when construction compaction and/or root damage is added, it can have disastrous effects.
Root damage
The way roots are severed or cut when trenching occurs is also important. Roots should be cut cleanly. Torn or ripped roots are prone to uneven regeneration and rot. They often do not grow back properly and are significantly more prone to damage from insects and disease. We are often make clean cuts to large exposed woody roots after trenching has been done.
Above-ground pool concerns
Above-ground pools pose different challenges. Some above-ground pools are temporary and some are left up for years. In either case, most above ground pools have a non-porous vinyl bottom which restricts oxygen and has the weight of the water pushing down on the soil below. If tree roots are in the soil under the pool, they can be oxygen deprived and compacted by the weight of the water.
We recommend putting the above ground pools as far away from trees as possible. If you have a smaller yard, and want to put up an above ground pool, we recommend putting it in the area of the yard with the least amount of absorbing tree roots. The further from the base of the tree, the less dense the absorbing roots are. Additionally, if you just put the pool up for the hottest summer months and take it down in the fall, the damaged absorbing roots have a chance to regenerate over the fall and spring months, reducing tree stress.
Overall there are many things to consider. Deep root fertilization before and after pool construction is generally recommended to help counter the effects of construction stress. It is always better to contact us prior to construction than after irreversible damage has been done. You don’t want the investment you made in a beautiful new pool to be overshadowed by a dead or dying tree!