Cause:
Epicormic roots do not provide structural stability for the tree and are prone to bending, often growing in a circling pattern. If the roots grow close enough to the tree trunk they will compress the sapwood and eventually cut off the flow of water and nutrients. This disorder is called Stem Girdling Root Syndrome (SGR) and is one of the primary causes of tree decline in urban landscapes. Without treatment, SGR’s will eventually prove fatal to the tree.
Assessment and Treatment:
Prevention is the best solution, but for trees already planted, early diagnosis of visible
symptoms is essential for future tree health. Trees
without a visible root flare at soil level are
symptomatic of the disorder and are at risk to
develop roots that
may girdle the trunk.
Diagnosis can also be
based on tree
species. For example,
maples and lindens
are more prone to the
disorder than are
oaks.
To assess the situation, root excavation is necessary. An Air-Spade® is used to blow debris and soil away from the base of a tree, exposing the root collar. This evaluation determines the possibility of improving a trees’ condition. If it is determined that problematic roots may be safely treated, surgical cuts are made to the roots impacting trunk growth. It may be necessary to leave some offending roots, as only roots that do not affect tree stability and structure will be removed. There must also be enough roots left intact to provide sufficient nutrient/water uptake. If tree stem compression by girdling roots is too severe, removal of the tree is the only option.
Possible Indications:
After Care:
As trees stressed by girdling root syndrome are more vulnerable to other problems, special care should
be taken to:
Rainbow Treecare is working closely with garden centers, landscapers and homeowners in the Twin Cities to assure that new tree plantings do not promote girdling root syndrome. If you have any questions on how to plant a tree properly to avoid circling roots, please contact your Consulting Arborist, review our on-line fact sheet on tree planting, or call our office at 952-922-3810.