tree root graphic

Tree Root Growth Misconceptions

Arborists are often asked how deep or wide a tree roots will grow, and there is just not as straight forward of an answer as some would like to believe. Truthfully trees are opportunists, when given the need, they will grow wider.

There are three components needed to a tree’s growth:  water, oxygen and soil compaction. These factors can allow trees to grow to great depths, however, it is rare. The large supporting root system, where the majority of roots are concentrated, is found in the first two feet of soil. This shallow area near the surface is typically rich in oxygen, mineral and moisture. Making this top layer a healthy spot for roots to grow.

Urban trees especially are typically found in more compacted soils without good water drainage and often have shallow, horizontal root systems. Again, with most roots being between 2-6 ft deep.  There is one report of a tree that grew roots to a depth of 174 feet, so obviously they do have the ability to grow deeper.

It’s important to note that open-grown trees typically have a more extensive root system than trees planted closely together. When planted close, a tree must compete for resources. Therefore, if you are planting a tree, it helps to know how large the crown will be at maturity. Once you know that length, multiply it by 1.5 and then designate that area for your tree. You can still plant shrubs, perennials and your lawn in that area, but it’s best to keep its distance from a building, foundation, or vegetable garden.

As always, if you have questions or concerns about your trees and their roots call one of our certified ISA arborists today!

Get a Quote

Looking for expert tree care? Fill out the form below and we’ll be in touch!

Looking for expert tree care?