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Problematic Tree Roots

tree rootsRole of roots

Most people know that tree roots are required to stabilize a tree in a vertical position, especially those roots that grow horizontally from the base of the trunk or stem. However, that is only part of their job. They also absorb oxygen, water and nutrients (such as nitrogen, potassium and phosphorus) from the soil, are then conveyed to the rest of the tree. All of these elements are essential for the tree’s growth and overall health. Tree roots also store starches that are produced during the growing season and are essential for growth and survival. If a tree’s roots are damaged significantly, it will become stressed and its health will decline and could lead to death.

Surface Roots

Surface roots are common in some species of tree (e.g. maples) once they reach maturity.  At this stage in the tree's life there are many benefits to the homeowner such as shade, habitat for wildlife, reducing noise pollution, increasing neighborhood safety, improving home value, reducing heating costs, absorbing carbon dioxide and producing oxygen and preventing soil erosion and flooding.   If tree roots are cut, the tree could become susceptible to infection, instability and death.  If roots are covered with too much soil, roots can become smothered which will compromise the health of the tree.

Grass can also compete with the tree for nutrients, making the tree weak and a likely host for infection.  The tree is also likely to have roots that resurface again. The best way to care for your tree's health and continued success, as well as address on-the-ground situations is to mulch over the tree roots.  Put down enough mulch to even the level with the top of the roots so that you can walk without tripping.  You can also install decorative rocks or boulders to complement your naturally beautiful lawn. 

Roots in Sewers

Tree roots do not crack intact pipes.  They will, however, invade and clog pipes that have pre-existing openings or cracks and cause leakage.  Sewer connection pipes are usually 1.4-2.5m below ground level, while tree roots grow almost exclusively in the upper meter of soil.  To survive, roots require both water and oxygen, which decrease in abundance with increasing soil depth.  Leaking pipes provide oxygen and nutrient rich water which draws tree roots deeper into the soil than they would normally be, allowing them to infiltrate pre-existing openings.  If you think you might have roots in your pipes please contact the Environment Division of the City of Thunder Bay at 625-2836.

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