Wells Lawn Care & Landscaping Logo
Get Custom Quote!

Determining the cause of dieback and decline symptoms

Can be very difficult to determine mainly due to cultural, environmental, and biological factors that could be involved. The usual culprit when dealing with tree problems is the base of the tree trunk and the roots. Stem Girdling Roots (SGR) are one of the most common and preventable long-term tree decline.

Stem Girdling Roots (SGR)

SGR is a root that girdles at the stem/truck. This is vital to understand because the tree is unintentionally killing itself as it expands and grows, this will lead to long-term decline. The diameter of the root and trunk will increase as they expand and grow, when. they contact each other they create a layer of compression that begins to strangle the tree. This will disrupt the flow of water and nutrients that move carbohydrates from moving down from the top of the tree. The effects of SGR will take time to become apparent, some trees will not visibly show any decline symptoms, but they may start to lean in the landscape or start to become unstable.

Compacted Roots. 

SGRs develop if your soil is not compacted or if the roots are growing within a limited area, this could happen by planting a bare root into a hole/plot that is too small for the root system. This can lead to forcing roots into different directions or circling the base itself. Applying to much mulch can cause the tree to be tricked into thinking the soil line is higher than it really is making the tree grow in search of new soil.

The most common culprit of SGR is pot-bound nursery stock, the longer the tree or plant is in the container, the greater the chance there will be roots that sit against the sit of the pot. When you re-pot the plant or tree the roots can be pushed into different directions and that might lead to SGR also.

When identified, and if the SGR is not severe you can remedy the SGR by removing the root as long as the root is not the main conduit for providing nutrients to the plant/tree. When possible it is an easier task to prevent SGR by ensuring good soil conditions, root space, and tree screening for circling roots.


Sources used:

Purdue Landscape Report: https://www.purduelandscapereport.org/article/stem-girdling-roots/

Author: John Bonkowski, March 29.2022