A Common Issue With Trees In Landscapes: Girdling Roots

A Common Issue With Trees In Landscapes: Girdling Roots

In today’s TrueTreeTalk post, we look at a common issue with trees in landscapes: girdling roots.  Learn what they are, the signs of them, what causes them, and ways to prevent and remedy the situation.

What are Girdling Roots?

Girdling roots are roots that grow around a tree’s trunk.  They can be at the soil level or just below it.  They can cut off the flow of water and nutrients in a tree and can prevent photosynthates produced in the leaves from getting to the tree’s roots.  They can also weaken the stability of the tree causing it to lean and potentially fall.

Roots can also grow over other roots, but this isn’t the same issue as when roots grow around the trunk.

Some trees can be more susceptible to girdling roots than others, but all can develop them.

Signs of Girdling Roots?

There are a number of signs of girdling roots.

One of them is a tree with a straight or narrow base, rather than one that flares out.  Think of a pole in the ground rather than the base of a cone.  This might be all around the tree, or one side if there is girdling on that one side.

There may also be a depression on one side of the trunk, where the roots are girdling.

A tree with girdling roots may have thinning of its crown and reduced growth.  Leaves can change color, fall early, or have reduced size.  Twigs and branches can die back.

In some cases, girdling roots can be seen under the soil surface.

When a tree has girdling roots, it is a stress on the tree.  This can compound with other stresses and leave the tree vulnerable to pests and disease.

Girdling roots can cause a tree to decline gradually over time.  The whole process can take years in some cases.

Causes of Girdling Roots?

One main cause of girdling roots is a tree that was left in a planting container too long and then poorly planted.  When a tree is left in a container too long, the roots can begin the circle.  If the tree is then planted without the roots being spread out, the roots could start to girdle the tree.

Similarly, if a tree is planted too deeply, in soil that is too compacted, too close to an obstruction, with the root flare covered with dirt, and or with mulch too close to the base of the tree, girdling roots can develop.

Ways to Prevent/Remedy Girdling Roots

There are ways to prevent girdling roots.

First, trees in containers should be inspected for circling roots.  Those with severe circling should be avoided.  Those with less or no circling should be planted properly.

Second, proper planting/transplanting should be done by a professional.  Some things to look out for include:

 planting the tree at the right depth, 

 digging the planting hole two the three times the diameter of the root ball, 

 not sloping the sides of the planting hole, 

 not smoothing the sides of the planting hole,

 not planting a tree in wet soil, 

 spreading out the roots of the tree at planting time, 

 not leaving container or other debris in the planting hole,

 applying mulch properly around the tree, and

 not planting a tree in compacted soil.

If potentially girdling roots are prevented at planting/transplanting time, the likelihood of the problem developing in the future can be reduced.

Third, having your trees inspected by a qualified arborist regularly can help catch the problem of girdling roots early and they can help to potentially reduce the problem before it gets too severe.  If the problem is caught early, it is easier to treat than if caught late.  A qualified professional can remove girdling roots in some situations, and this can help to alleviate the problem.  In some cases though, if a tree has a severe problem with girdling roots, the tree may need to be removed.

Although things that are generally beneficial for trees such as proper fertilization and proper pruning have a number of benefits, they are not a treatment for girdling roots and will not reduce the effects of the situation.

If you found learning about girdling roots informative, check out the other posts on our TrueTreeTalk blog.  Follow us on Facebook to keep up with these and other posts.

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ArborTrue is a science-based tree-service company in the greater Houston area.  We also serve Austin and other parts of Central Texas.  We provide a range of services including tree trimming, tree pruning, tree removal, tree planting, arborist consultations, and more.  Call us today at 832-980-8733 (Houston) or at 512-546-3833 (Austin) or reach out to us online to schedule an appointment.