I've noticed over the years that in clear cut timbers the 'seng will continue to put a stalk up for a few years after the clear cutting but die back each year quite early due to all the sun exposure. Eventually these roots just quit putting up a stalk all together. My question is how long will the root lay dormant until new tree regrowth provides optimum shade or will the root just finally die off completely?

I think they may just eventually die off.I've really noticed over the years the amount of weeds that are taking over in the woods. Which isn't good for ginseng.

Same here blackhammer. Selective logging really opens up the timber sometimes and thats all it takes to make the under growth take off. Multi flora, Raspberrys, nettles, etc. all thrive once the canopy is opened up a little. It does also help the 'seng grow bigger faster in many cases, as long as there isn't too much sun like a clear cut. My biggest plants almost always come from recently logged timbers in amongst the top piles. I don't know how many times I've crawled into a raspberry thicket or multi flora to get at a half dozen giant 4s decked out in their full fall gold splender. Some that are getting too much sun even turn a bright reddish color. "Hawkeye Gold" we call it in these parts. LOL

I've seen a few of those reddish colored ones myself.Was out this morning and only dug eight plants but they were beautiful roots.This cool weather ,the smell of fall in the air,made it a enjoyable few hours.The plants seem in pretty good shape yet.Going to have to get out a few more times.

If we was sitting together so we could talk face to face, I have lots of ideas about how seng grows under different conditions. I think that the foliage has a lot to do with the way seng determines if it is going to come up in certain years. I have also been told by certain people that seng actually growes without sending up a top. I always thought the top had to feed the root, but, some say differently. I have saw lots of red colored seng plants from getting lots of sun. Some of the best berry heads come from lots of sunlight.
Some of the best seng digging I ever had came from cow pastures in the woods. Cows eat the berries then deposit them in different places and the cow manure helps the roots grow big. I always find lots of big plants in that kind of situation and mostly find them in big brushy spots where the cows can't east the plants easy or trample them.

Dug some very nice roots just the other day in a pastured timber. Just like you described Don, they were in amongst old brush piles.