{"id":2570,"date":"2025-08-18T14:50:50","date_gmt":"2025-08-18T14:50:50","guid":{"rendered":"http:\/\/blog.bartlett.com\/?p=2570"},"modified":"2025-08-18T19:25:16","modified_gmt":"2025-08-18T19:25:16","slug":"hidden-dangers-buried-root-collars","status":"publish","type":"post","link":"https:\/\/www.bartlett.com\/blog\/hidden-dangers-buried-root-collars\/","title":{"rendered":"The hidden dangers of buried root collars"},"content":{"rendered":"

A tree gets the water and nutrients it needs from the roots. If that tree has a buried root collar, a portion of the root system is severed, or the roots are otherwise compromised, the tree will suffer proportionately. Buried root collars<\/a> are a common and serious issue.<\/p>\n

\"ExcavatedWhat you can’t see can hurt your trees<\/h3>\n

As roots serve as an anchor to keep the tree upright, when there is a problem with the roots, there is also a problem with the structural stability of the tree. With roots having such vitally important duties, their management is an essential part of tree care. An “out of sight, out of mind” mentality can result in catastrophic consequences.<\/p>\n

With this in mind, your trees should have a visible flare where the roots curve out of the ground.\u00a0 Unfortunately, the root collar area is often \u2018buried\u2019 under soil or mulch.\u00a0 This happens when the tree is planted too deeply or when excessive mulch is piled against the trunk.<\/p>\n

What’s happening underground<\/h3>\n
\"\"
Tree roots extend well beyond the dripline, sometimes as far as three times.<\/figcaption><\/figure>\n

Roots grow where the resources they need are located. That means most of a tree’s fine feeder roots are in the top twelve inches or so of soil. Large structural roots may grow several feet deep, <\/span>depending on species and soil conditions. These large roots grow closer to the trunk of the tree with fine feeder roots extending one to two times the height of the tree.<\/span><\/p>\n

\n

Porous spaces in the soil allow for better root growth and subsequent absorption of water and nutrients. When the soil is compacted, these porous spaces are reduced, making it difficult for roots to extend and do their crucial work. This is a common issue on urban and suburban properties where trees coexist with people, machinery, pavement and structures. Soil compaction and inadequate aeration are major barriers to tree growth.<\/p>\n

The root collar cover-up<\/h3>\n

It’s often said that the cover-up of a mistake causes more trouble than the mistake itself. And so it is with trees. When soil or excess mulch is piled against the lower trunk, problems with the root system are often ‘covered up.’ If you have trees that seem to grow straight from the ground (like telephone poles), those trees are likely in trouble from buried root collars.<\/p>\n

\"\"
Girdling roots slowly strangle a tree, restricting movement of water and nutrients.<\/figcaption><\/figure>\n

The root collar is the transition area between a tree’s trunk and its roots. While a tree’s roots are able to tolerate high levels of soil moisture, the above-ground root collar is not. When buried, the root collar remains damp and moist, increasing the likelihood of insects and disease and inhibiting the movement of oxygen and carbon dioxide. One specific example is infection by root-attacking fungi such as Phyophthora and Armillaria.\u00a0<\/span><\/p>\n

<\/p>\n

Excess soil or mulch can also hide girdling roots<\/a>. These lateral roots sit at or just below the soil line, encircling and pressing into the main trunk. Root collar excavation<\/a> can remove excess soil and mulch to uncover issues. When discovered, <\/span>girdling roots should be removed, but this must be done with care to minimize injury to the trunk and impact to overall tree health.<\/p>\n

\"removing
When seen in the root collar area, girdling tree roots should be carefully removed.<\/figcaption><\/figure>\n

What’s happening above ground?<\/h3>\n

Even though you can’t see what’s going on with the roots of your trees, they’ll let you know a problem exists.<\/p>\n

Symptoms of a root issue include:<\/p>\n