Best of luck with your seng. Poaching is a real threat to all of us who grow it. Best of luck to us all on that.
Hill.. that is a sweet looking pile of roots. Only thing missing is the longer necks. I think the size is impressive for that age and shape and appearance looks great. Sure looks like wild to me apart from the root size to neck length issue.
I have a spot down on a creek bluff close to my home that grows em big and fat... 1/2 oz to 1 oz roots with only 6-8 flats on the neck. It is just the result of ideal growing location (lots of morning sun, excellent dirt). I think yours are growing in excellent location too so you are getting similar retults, perhaps even better.
Below is a pic from 2010 when I first hunted that creek bluff spot. The 4 smaller roots (upper right) were all 20+ years old, and quite small. They came from the regular woods on a north facing hillside. that is what most of my seng close to home looks like. But the rest of those big fat roots (with short necks) came from that creek bluff area, getting lots of morning sun. They do look similar to yours.