Hello Patrick.
I think I see enough past the spelling to read your note. I often visit a blog where the lead has dyslexia also.
Last spring, I seen more girdling than I wanted around the farm, all by mice or rabbits I think. I did read some piece of literature which said voles are more prone to girdle than mice, and I have voles on the farm as well, so maybe they were involved.
There is a paper out of the US Forest Labs on tools that can be used to girdle trees.
https://www.fs.fed.us/t-d/pubs/pdfpubs/pdf99242809/pdf99242809pt01.pdf
Woodweb is a web site for people wanting to produce wood and things from wood. Not really hobby-ist. They have a thread on girdling as well.
http://www.woodweb.com/knowledge_base/Girdling_standing_lumber_and_why_not.html
Girdling is used to increase fruit production with some crops, and I think I would describe the result you seen as an example of this. But in the little research I've done, I have seen nothing like what you have written about.
I am just starting my adventures with trees and planting them. In large part I want to remove most branches below something like 15-20 feet, so that I can get my lawnmower underneath the branches (it is meant to do fairways at golf courses). My interest also involves species like black locust, which I think would sprout if exposed to your treatment.
One source I read, suggests that some diseases (like blue stain) could make themselves present if this was done.
While girdling is a way to kill trees, it is not immediate. Some anecdotes talk about a girdled tree surviving for 2 or 3 years before dying. It is apparently not felt to be a good way to produce dead standing trees for wildlife to use in the forest. At some point, the dead trees will lose limbs. Girdling was practiced in agriculture before there was equipment readily available to fell trees. And apparently some early farmers lost their lives to falling limbs. The girdling point also tends to be the location where the trunk eventually fails, and the (remaining) tree falls. Unlike falling a tree deliberately today, because there are no controlling cuts with the girdle or use of wedges, the trunk could fall in directions that are inconvenient, and it could fail in ways that cause a lot of damage to the wood of the trunk. I would hope that if a tree was properly cut down shortly after dying from being girdled, that a person could harvest this section of the tree. Perhaps the place to start with this would be in trying to grow fence posts, which are only a few inches thick. That way a person can get a statistically valid sample size in a relatively short period of time. And if a person was growing a species like black locust, the tendency to produce sprouts would actually be wanted so as to get a start on the next set of fence posts.