POC,
They way you describe your plants sounds similar to mine around here close to my home.
It is very rare to find a 4 prong in the array of hollows behind my house. Decent 3 prongs is about it and a really nice one would be a 3 prong that was 12-14\" tall and has 10-12 berries.
But now the woods behind my home has big mature timber, deep shade, and the calcium levels are just at the minimum for growing seng (between 1200-1600 mostly). Seng grows there but it does not really thrive like I have seen it thrive in other places.
Here is a pic of of 3 prong that is about the average size of mature ginseng in that location.
I have harvested a many seng plant in those hollows that looked just like that and were 20-25+ years old.
But down where those hollows run into the main hollow (down at the big creek) it changes direction and there is a bluff that faces due east.
The soil there is a different color, and just filled with rock chips, all around that bluff section. Also the seng growing there gets quite a bit of sun, but only in the morning hours. After about noon, they get nothign but indirect light, but until then they get some realy good morning sun.
Along that bluff the seng I find is huge, has big broad leaves, and longer berry stems, and big wads of berries. I found several nice 4 prongs in the 18-24\" tall range.
I will post some pics of them in the next post.
TNhunter