This is the one I got. It is currently out of stock, but maybe it will help find some recommended similar items. https://smile.amazon.com/gp/product/B07DBYXKM7/
You can also find it sold as tree protector / mulch rings designed for sitting on top of the soil, but I found the crafting fabric felt was cheaper for more area at the time.
I dug up my bald cypress that I’m ground growing so that I could address roots and rotate it. At first I thought that I didn’t have it in a grow bag. Turns out it just lifted itself out of the bag a bit. Some roots also escaped. Mostly feeders, but some fairly large ones. In a year and a half it grew from ~1" in diameter to ~5.5" in diameter. I cut back a bunch of roots below as well as addressed any potential circling and/or crossing roots above. Unfortunately I destroyed the bag when I dug it up.
In one of the images you can see the bucket lid that its growing on top of. The tap root hit the lid and then circled around and then back down the side. When I did the root work I didn’t go too far up into the base. Basically hit that tap root and then stopped.
Escaping roots lol
Planted at a slight angle. While I’m not going for an upright flat top I also don’t want that much movement in it. Just subtle movement. I’ll wire a new leader from one of the many buds. The current leader doesn’t come out at an acute enough angle for me.
