To be healthy and structurally safe, trees need healthy and robust root systems – but when construction and renovation projects are planned, the potential damage to nearby trees and their roots is often overlooked or misunderstood. Root damage to trees caused by building construction and landscaping disturbances can have profound and long-lasting consequences to a tree’s health, its appearance, as well as its structural integrity and safety.
Very often root injury can be avoided if proper measures and precautions are taken to protect a tree’s root system before construction starts. One of these solutions is a non-invasive procedure that involves a process called pneumatic (or air) excavation. This is an invaluable tool that can resolve many conflicts between tree roots and construction projects without compromising the health and structural integrity of a tree – presenting a win-win scenario that meets development objectives while preserving a tree’s long-term survivability.
In this article we will outline some of the most common situations where construction and development may harm trees and describe how air excavation can be a lifesaving asset - protecting your trees while helping you achieve your home and property improvement goals.
Looking below ground - Understanding how tree roots grow
There is a common misconception that a tree’s roots mirror its width and height underground, growing deeply into the earth but not extending beyond the perimeter of its canopy. In fact, the opposite is true - tree roots grow wide and shallow - so wide that a tree’s root system usually extends outwards to two to three times the width of its branches.
Meanwhile, below ground, the vast majority of a tree’s roots usually only reach down to a depth of just 12-18 inches, even with tall and mature shade trees. Most of a tree’s root system is made up of fine absorbing roots which are vitally responsible for taking up the water, minerals, and air that a tree needs to grow and survive. While very expansive, these roots also tend to be very thin and fragile – which make them especially vulnerable to injury inflicted by the underground disturbances caused by landscaping, construction, and underground utility installations.
Keeping this in mind let’s take a look at some of the most common problems that occur with tree root and construction conflicts.
Digging and cutting roots harms trees
When construction or landscaping projects require digging near mature trees, protecting their root systems becomes crucial. Removing just one major tree root can result in the loss of one quarter of a tree’s root system, which is enough to jeopardize its health and structural safety. The use of invasive construction excavation machinery, such as shovels or backhoes, can sever significant portions of a tree’s root system and cause substantial and irreversible damage, leading to long-term harm or even tree death and eventual failure.
Regrading and soil compaction damage tree roots
Other common construction activities, such as regrading a slope and tamping down soil, can also harm the roots of a tree. Burying roots in just a few added inches of soil can suffocate them by blocking their access to oxygen and gas exchange. Soil compaction that results from installing a building foundation or driveway, as well as the weight of heavy equipment, can crush tree roots and destroy air pores in soil that are vital to gas exchange and water infiltration.
Improper planting also endangers trees
Unfortunately, especially in new housing and commercial developments, trees are often planted improperly with their roots and trunk bases buried too deep in soil. This presents a scenario where the trunk flare and roots of a tree are smothered and unable to access the air they require. As a response, new roots will grow adventitiously, but they tend to circle around the tree’s base - eventually strangling it – which will stress a tree and often cause branch dieback and the eventual death of the tree.
How does air excavation work?
A pneumatic excavation tool, often called an air spade, creates a jet of compressed air that removes soil from around – or underneath - tree roots without severing them, protecting trees from the type of damage that traditional digging equipment often inflicts. This non-invasive method significantly reduces the risk of root injury, disease, or stress, which helps maintain the overall health and stability of the tree.
Air spades can be used for a variety of purposes including
- Air tunneling under tree roots allows communication and utility lines, pipes, and conduit to be run underground below a tree’s root system without inflicting damage.
- Air spading loosens compacted soil around tree roots.
- Radial trenching around trees allows organic matter and soil amendments to be incorporated within the root zone of a large tree.
- Root collar excavations uncover buried root crowns and remove excessive soil and organic debris that have been piled against tree trunks.
- Air excavations can also be used for investigative purposes to examine and potentially prune out strangling and problematic tree roots that may be causing health issues that can affect the entire tree.
Monster Tree Service offers a full range of pneumatic excavation services prescribed and performed by our certified arborists and expert tree care professionals. If you are planning new construction or renovations for your home and landscape, giving us a call can be one of the most important steps you can take to save the lives of your trees – keeping them healthy and beautiful - while making improvements to your home and property.