I think the interest in elevation is due to the temp and moisture level of the forest. In WV ginseng tends to grow very well at about 1,200 foot above sea level according to an article I read. I also know morels will run a bit stronger along a certain elevation at times. So it must be due to temps and moisture.http://www.gancao.net/herbology/nature-of-ginseng-453
"Ginseng likes cold, dark and wet weather. Heat, too much light, or not enough moisture will kill it. It is very picky as to the quality of soil in which it will grow. It prefers deep loose soil that extends downward very deeply. It requires humus, or topsoil rich in nutrients of decomposing leaves from neighboring trees. It also prefers water that passes through the soil, rather than stagnating around the root."
I know some of the mountains in NY,PA,MD,WV,VA,TN and NC have many locations much higher that 1,200 foot above sea level that many of you guys on this board are used to hunting ginseng at.
I have not hunted ginseng in the mountains just the foot hills. So I would suspect many of you would know if higher elevations are truly cooler and moist which may be a reason for the interest in elevation.