Root Collar & Root Excavation and Pruning
Root collars are located at the base of a tree where the roots and the main trunk join together. It is the recognizable and iconic flare you see in paintings and photos which displays the glory and beauty of the mightiest of the plant kingdom. Where the above meets the below, the trunk grows much wider before disappearing under the soil’s surface where it branches out to form the root system.
Some background
The survival of a tree weighs on the survival of the collar, which requires an exchange of carbon dioxide and oxygen in and out of the inner bark (phloem). If this coming and going of gas is restricted by excess soil or mulch, and exacerbated by the presence of moisture, the phloem cells begin to die and the movement of food is restricted or halted. Another risk appears when the bark of a tree and collar rots from being left alone for too long. They cannot withstand the conditions existing in the soil like the roots of a tree can. Root dieback mixed with rotting of the trunk will greatly weaken and eventually, kill a tree if left untreated over many years. Tree death from collar or root issues can take approximately 5-20 years.
In an urban environment, tree root and collar excavation don’t have the popularity they should. However, the importance of a healthy root system and properly exposed collar are as important to the health, maintenance, life span, and stability of a tree as a proper crawl space, footing, and foundation are to a house’s ability to stand in a safe, rot-free condition. Although arguably more important to human lives (because, well, oxygen), trees are not held in the same regard as homes. Too often, the root cause (no pun intended) of a tree's decline goes misdiagnosed for what can be observed above the soil level without a second thought given to parts unseen. As they say, “Out of sight, out of mind.”
Reasons for Excavation & Root Pruning
Buried collar: Too often, the root collars of trees end up buried from a landscape project, grade change, or natural occurrences like the wind. Unfortunately, a common way for a collar to end up buried happens on the first day of its life, when planted at its new home. An over-eager new tree owner returns home from the nursery with their tree strapped on the roof and a brand new shovel in hand shouting, “Let the digging commence!” Then, they dig and dig and dig, making their new leafy friend a mega-motel to rest its roots in. Afterward, the root ball is pulled from the pot, plopped into the hole, and covered with soil and mulch just like the customer was advised. The hose comes next to prevent dehydration and immediately, the silent screams of a tree planted in a hole too deep, begin. If left to struggle in this environment, a tree will fight many uphill battles, only to lose time and time again and finally be reduced to a pile of wood chips.
Circling roots: Roots of a tree can begin to circle the trunk, constricting other roots and eventually, “girdling” the tree to death. Circling roots can be caused by a multitude of things like improper watering and planting. Improper watering can promote more vigorous root growth around the trunk rather than encouraging outward expansion. Similarly, improper planting coupled with the fact that container trees are grown and sold in circular pots can spell disaster. Proper steps must be taken prior to, and during the planting process, to prevent future headaches.
Girdling roots: Rather than growing outward and away from the trunk, a girdling root has grown across the trunk, restricting the flow of sap to and from the canopy and roots. Slowly but surely the tree will die, unable to properly disperse the water and nutrients meant to sustain it.
Soil compaction: Rocky or clay-heavy soils can create an unfriendly environment for roots. Pores in soil contain both oxygen and water and are greatly reduced in compacted growing mediums. This reduces and restricts the necessary availability of H2O and O2 to the tree. Compact soil around the soft and aerated soil of a freshly dug hole can also act as a barrier to budding roots. It is possible that when roots meet this harsh wall of unfriendly soil, they choose the path of least resistance which can lead to circling or girdling. This is especially true when the only water the tree receives is right atop its freshly dug hole.
Our Approach
Our team starts small and works our excavation zone out only as far as necessary. We start by utilizing high air pressure to carefully remove bits of soil until we find what we are looking for. Air is used predominantly in place of hand tools or water to avoid damaging the main root structure. The information gained during this initial step tells us a story about the tree’s suffering and oftentimes, provides options for remediation. Before the process begins we will explain what the project is going to entail while answering any questions.
If your tree is slowly weakening, or is missing the iconic trunk flare and enters the soil looking like a telephone pole, it may be worth setting up a free consultation. You will get a plethora of information about your tree, trees in general, and excavation of root systems. You'll also have the option to receive articles upon articles from top universities, tree industry leaders, and organizations that exist to advocate for—and educate others on—trees. We always prefer to save decades worth of growth, beauty, and benefits, rather than the easy route of removal. And if we are going to embark on this journey together we find it is best that you have access to as much information as possible regarding the process and possible outcomes and even the risks involved.
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“I have used Tony's Tree Service for a number of things so far. I really appreciated Anthony's knowledge and care when it came to my trees. He was very informative as to why he recommended what needed to be done right away, and what could wait.”
—Customer review