These illustrations are the very best I've come across and really should be viewed/reviewed from the novice to the expert.

Click on Photo 1 to get started

While 'circling roots' beneath the trunk that do not return up are something I will avoid or will repair, there are people with degrees in plant production that say these type of "spiraling roots" will not sacrifice a woody plant. Instead, they will warn it's the roots that return up and any that spiral the trunk itself known as girdling which happens only above the soil line, are the immanent danger, roots. I can't live though with 'spiraling roots' below a trunk...I simply lose sleep as a fact of the matter.

These photos are of a purchase recently of 'spiraling roots'. I suggested to the seller that a replacement was warranted because the roots were 'girdling'. That's when I was corrected regarding terminology and this very nice individual explained the difference from my roots and girdling roots. At any rate, I was issued another plant & life goes on.

Spiraling Roots Below The Trunk. Not Girdling Roots.
{{gwi:471354}}

Spiraling Roots Below The Trunk. Not Girdling Roots.
{{gwi:471355}}

Spiraling Roots Below The Trunk. Not Girdling Roots.
{{gwi:471356}}

Dax