I put one around my dogwood which I just transplanted from where my new ginko goldspire is now located. The ginko also got a ring. My hope is that mowing will be easier than with the block ring that had been around the dogwood when it was located in front of my home. Keeping the perfect circle seems impossible. It could be layed out perfectly round, but while pounding it in the ground the shape will change. But it is close enough; I doubt anyone will bring out a compass and check it.